Antenna (radio)

An antenna (or aerial) is a transducer that transmits or receives electromagnetic waves. In other words, antennas convert electromagnetic radiation into electrical current, or vice versa. Antennas generally deal in the transmission and reception of radio waves, and are a necessary part of all radio equipment. Antennas are used in systems such as radio and television broadcasting, point-to-point radio communication, wireless LAN, cell phones, radar, and spacecraft communication. Antennas are most commonly employed in air or outer space, but can also be operated under water or even through soil and rock at certain frequencies for short distances.

Physically, an antenna is an arrangement of one or more conductors, usually called elements in this context. In transmission, an alternating current is created in the elements by applying a voltage at the antenna terminals, causing the elements to radiate an electromagnetic field. In reception, the inverse occurs: an electromagnetic field from another source induces an alternating current in the elements and a corresponding voltage at the antenna's terminals. Some receiving antennas (such as parabolic and horn types) incorporate shaped reflective surfaces to collect the radio waves striking them and direct or focus them onto the actual conductive elements.

Some of the first rudimentary antennas were built in 1888 by Heinrich Hertz (1857–1894) in his pioneering experiments to prove the existence of electromagnetic waves predicted by the theory of James Clerk Maxwell. Hertz placed the emitter dipole in the focal point of a parabolic reflector. He published his work and installation drawings in Annalen der Physik und Chemie (vol. 36, 1889).

Terminology

The words antenna (plural: antennas and aerial are used interchangeably; but usually a rigid metallic structure is termed an antenna and a wire format is called an aerial. In the United Kingdom and other British English speaking areas the term aerial is more common, even for rigid types. The noun aerial is occasionally written with a diaeresis mark—aërial—in recognition of the original spelling of the adjective aërial from which the noun is derived.

The origin of the word antenna relative to wireless apparatus is attributed to Guglielmo Marconi. In 1895, while testing early radio apparatuses in the Swiss Alps at Salvan, Switzerland in the Mont Blanc region, Marconi experimented with early wireless equipment. A 2.5 meter long pole, along which was carried a wire, was used as a radiating and receiving aerial element. In Italian a tent pole is known as l'antenna centrale, and the pole with a wire alongside it used as an aerial was simply called l'antenna. Until then wireless radiating transmitting and receiving elements were known simply as aerials or terminals. Marconi's use of the word antenna (Italian for pole) would become a popular term for what today is uniformly known as the antenna.

A Hertzian antenna is a set of terminals that does not require the presence of a ground for its operation (versus a Tesla antenna which is grounded. A loaded antenna is an active antenna having an elongated portion of appreciable electrical length and having additional inductance or capacitance directly in series or shunt with the elongated portion so as to modify the standing wave pattern existing along the portion or to change the effective electrical length of the portion. An antenna grounding structure is a structure for establishing a reference potential level for operating the active antenna. It can be any structure closely associated with (or acting as) the ground which is connected to the terminal of the signal receiver or source opposing the active antenna terminal.

In colloquial usage, the word antenna may refer broadly to an entire assembly including support structure, enclosure (if any), etc. in addition to the purely functional components.

Antennas have practical uses for the transmission and reception of radio frequency signals such as radio and television. In air, those signals travel very quickly and with a very low transmission loss. The signals are absorbed when moving through more conductive materials, such as concrete walls or rock. When encountering an interface, the waves are partially reflected and partially transmitted through.

A common antenna is a vertical rod a quarter of a wavelength long. Such antennas are simple in construction, usually inexpensive, and both radiate in and receive from all horizontal directions (omnidirectional). One limitation of this antenna is that it does not radiate or receive in the direction in which the rod points. This region is called the antenna blind cone or null.

There are two fundamental types of antenna directional patterns, which, with reference to a specific two dimensional plane (usually horizontal [parallel to the ground] or vertical [perpendicular to the ground]), are either:

1. Omni-directional (radiates equally in all directions), such as a vertical rod (in the horizontal plane) or
2. Directional (radiates more in one direction than in the other).

In colloquial usage "omnidirectional" usually refers to all horizontal directions with reception above and below the antenna being reduced in favor of better reception (and thus range) near the horizon. A "directional" antenna usually refers to one focusing a narrow beam in a single specific direction such as a telescope or satellite dish, or, at least, focusing in a sector such as a 120° horizontal fan pattern in the case of a panel antenna at a cell site.

All antennas radiate some energy in all directions in free space but careful construction results in substantial transmission of energy in a preferred direction and negligible energy radiated in other directions. By adding additional elements (such as rods, loops or plates) and carefully arranging their length, spacing, and orientation, an antenna with desired directional properties can be created.

An antenna array is two or more simple antennas combined to produce a specific directional radiation pattern. In common usage an array is composed of active elements, such as a linear array of parallel dipoles fed as a "broadside array". A slightly different feed method could cause this same array of dipoles to radiate as an "end-fire array". Antenna arrays may be built up from any basic antenna type, such as dipoles, loops or slots.

The directionality of the array is due to the spatial relationships and the electrical feed relationships between individual antennas. Usually all of the elements are active (electrically fed) as in the log-periodic dipole array which offers modest gain and broad bandwidth and is traditionally used for television reception. Alternatively, a superficially similar dipole array, the Yagi-Uda Antenna (often abbreviated to "Yagi"), has only one active dipole element in a chain of parasitic dipole elements, and a very different performance with high gain over a narrow bandwidth.

An active element is electrically connected to the antenna terminals leading to the receiver or transmitter, as opposed to a parasitic element that modifies the antenna pattern without being connected directly. The active element(s) couple energy between the electromagnetic wave and the antenna terminals, thus any functioning antenna has at least one active element. A careful arrangement of parasitic elements, such as rods or coils, can improve the radiation pattern of the active element(s). Directors and reflectors are common parasitic elements.

An antenna lead-in is the medium, for example, a transmission line or feed line for conveying the signal energy between the signal source or receiver and the antenna. The antenna feed refers to the components between the antenna and an amplifier.

An antenna counterpoise is a structure of conductive material most closely associated with ground that may be insulated from or capacitively coupled to the natural ground. It aids in the function of the natural ground, particularly where variations (or limitations) of the characteristics of the natural ground interfere with its proper function. Such structures are usually connected to the terminal of a receiver or source opposite to the antenna terminal.

An antenna component is a portion of the antenna performing a distinct function and limited for use in an antenna, as for example, a reflector, director, or active antenna.

An electromagnetic wave refractor is a structure which is shaped or positioned to delay or accelerate transmitted electromagnetic waves, passing through such structure, an amount which varies over the wave front. The refractor alters the direction of propagation of the waves emitted from the structure with respect to the waves impinging on the structure. It can alternatively bring the wave to a focus or alter the wave front in other ways, such as to convert a spherical wave front to a planar wave front (or vice-versa). The velocity of the waves radiated have a component which is in the same direction (director) or in the opposite direction (reflector) as that of the velocity of the impinging wave.

A director is a parasitic element, usually a metallic conductive structure, which re-radiates into free space impinging electromagnetic radiation coming from or going to the active antenna, the velocity of the re-radiated wave having a component in the direction of the velocity of the impinging wave.

A reflector is a parasitic element, usually a metallic conductive structure (e.g., screen, rod or plate), which re-radiates back into free space impinging electromagnetic radiation coming from or going to the active antenna. The velocity of the returned wave has a component in a direction opposite to the direction of the velocity of the impinging wave. The reflector modifies the radiation of the active antenna.

An antenna coupling network is a passive network (which may be any combination of a resistive, inductive or capacitive circuit(s)) for transmitting the signal energy between the active antenna and a source (or receiver) of such signal energy.

There are several critical parameters affecting an antenna's performance that can be adjusted during the design process. These are resonant frequency, impedance, gain, aperture or radiation pattern, polarization, efficiency and bandwidth. Transmit antennas may also have a maximum power rating, and receive antennas differ in their noise rejection properties. All of these parameters can be measured through various means.

Typically, antennas are designed to operate in a relatively narrow frequency range. The design criteria for receiving and transmitting antennas differ slightly, but generally an antenna can receive and transmit equally well. This property is called reciprocity.

Resonant frequency

The "resonant frequency" and "electrical resonance" is related to the electrical length of an antenna. The electrical length is usually the physical length of the wire divided by its velocity factor (the ratio of the speed of wave propagation in the wire to c0, the speed of light in a vacuum). Typically an antenna is tuned for a specific frequency, and is effective for a range of frequencies that are usually centered on that resonant frequency. However, other properties of an antenna change with frequency, in particular the radiation pattern and impedance, so the antenna's resonant frequency may merely be close to the center frequency of these other more important properties.

Antennas can be made resonant on harmonic frequencies with lengths that are fractions of the target wavelength; this resonance gives much better coupling to the electromagnetic wave, and makes the aerial act as if it were physically larger.

Some antenna designs have multiple resonant frequencies, and some are relatively effective over a very broad range of frequencies. The most commonly known type of wide band aerial is the logarithmic or log periodic, but its gain is usually much lower than that of a specific or narrower band aerial.

Gain

Gain as a parameter measures the efficiency of a given antenna with respect to a given norm, usually achieved by modification of its directionality. An antenna with a low gain emits radiation with about the same power in all directions, whereas a high-gain antenna will preferentially radiate in particular directions. Specifically, the Gain, Directive gain or Power gain of an antenna is defined as the ratio of the intensity (power per unit surface) radiated by the antenna in a given direction at an arbitrary distance divided by the intensity radiated at the same distance by a hypothetical isotropic antenna.

The gain of an antenna is a passive phenomenon - power is not added by the antenna, but simply redistributed to provide more radiated power in a certain direction than would be transmitted by an isotropic antenna. If an antenna has a gain greater than one in some directions, it must have a gain less than one in other directions, since energy is conserved by the antenna. An antenna designer must take into account the application for the antenna when determining the gain. High-gain antennas have the advantage of longer range and better signal quality, but must be aimed carefully in a particular direction. Low-gain antennas have shorter range, but the orientation of the antenna is relatively inconsequential. For example, a dish antenna on a spacecraft is a high-gain device that must be pointed at the planet to be effective, whereas a typical Wi-Fi antenna in a laptop computer is low-gain, and as long as the base station is within range, the antenna can be in any orientation in space. It makes sense to improve horizontal range at the expense of reception above or below the antenna. Thus most antennas labelled "omnidirectional" really have some gain.[4]

In practice, the half-wave dipole is taken as a reference instead of the isotropic radiator. The gain is then given in dBd (decibels over dipole):

NOTE: 0 dBd = 2.15 dBi. It is vital in expressing gain values that the reference point be included. Failure to do so can lead to confusion and error.



Radiation pattern

The radiation pattern of an antenna is the geometric pattern of the relative field strengths of the field emitted by the antenna. For the ideal isotropic antenna, this would be a sphere. For a typical dipole, this would be a toroid. The radiation pattern of an antenna is typically represented by a three dimensional graph, or polar plots of the horizontal and vertical cross sections. The graph should show sidelobes and backlobes, where the antenna's gain is at a minima or maxima.

Impedance

As an electro-magnetic wave travels through the different parts of the antenna system (radio, feed line, antenna, free space) it may encounter differences in impedance (E/H, V/I, etc.). At each interface, depending on the impedance match, some fraction of the wave's energy will reflect back to the source,[5] forming a standing wave in the feed line. The ratio of maximum power to minimum power in the wave can be measured and is called the standing wave ratio (SWR). A SWR of 1:1 is ideal. A SWR of 1.5:1 is considered to be marginally acceptable in low power applications where power loss is more critical, although an SWR as high as 6:1 may still be usable with the right equipment. Minimizing impedance differences at each interface (impedance matching) will reduce SWR and maximize power transfer through each part of the antenna system.

Complex impedance of an antenna is related to the electrical length of the antenna at the wavelength in use. The impedance of an antenna can be matched to the feed line and radio by adjusting the impedance of the feed line, using the feed line as an impedance transformer. More commonly, the impedance is adjusted at the load (see below) with an antenna tuner, a balun, a matching transformer, matching networks composed of inductors and capacitors, or matching sections such as the gamma match.


Efficiency

Efficiency is the ratio of power actually radiated to the power put into the antenna terminals. A dummy load may have an SWR of 1:1 but an efficiency of 0, as it absorbs all power and radiates heat but not RF energy, showing that SWR alone is not an effective measure of an antenna's efficiency. Radiation in an antenna is caused by radiation resistance which can only be measured as part of total resistance including loss resistance. Loss resistance usually results in heat generation rather than radiation, and reduces efficiency. Mathematically, efficiency is calculated as radiation resistance divided by total resistance.

Bandwidth

The bandwidth of an antenna is the range of frequencies over which it is effective, usually centered on the resonant frequency. The bandwidth of an antenna may be increased by several techniques, including using thicker wires, replacing wires with cages to simulate a thicker wire, tapering antenna components (like in a feed horn), and combining multiple antennas into a single assembly and allowing the natural impedance to select the correct antenna. Small antennas are usually preferred for convenience, but there is a fundamental limit relating bandwidth, size and efficiency.

Polarization

The polarization of an antenna is the orientation of the electric field (E-plane) of the radio wave with respect to the Earth's surface and is determined by the physical structure of the antenna and by its orientation. It has nothing in common with antenna directionality terms: "horizontal", "vertical" and "circular". Thus, a simple straight wire antenna will have one polarization when mounted vertically, and a different polarization when mounted horizontally. "Electromagnetic wave polarization filters" are structures which can be employed to act directly on the electromagnetic wave to filter out wave energy of an undesired polarization and to pass wave energy of a desired polarization.

Reflections generally affect polarization. For radio waves the most important reflector is the ionosphere - signals which reflect from it will have their polarization changed unpredictably. For signals which are reflected by the ionosphere, polarization cannot be relied upon. For line-of-sight communications for which polarization can be relied upon, it can make a large difference in signal quality to have the transmitter and receiver using the same polarization; many tens of dB difference are commonly seen and this is more than enough to make the difference between reasonable communication and a broken link.

Polarization is largely predictable from antenna construction but, especially in directional antennas, the polarization of side lobes can be quite different from that of the main propagation lobe. For radio antennas, polarization corresponds to the orientation of the radiating element in an antenna. A vertical omnidirectional WiFi antenna will have vertical polarization (the most common type). An exception is a class of elongated waveguide antennas in which vertically placed antennas are horizontally polarized. Many commercial antennas are marked as to the polarization of their emitted signals.

Polarization is the sum of the E-plane orientations over time projected onto an imaginary plane perpendicular to the direction of motion of the radio wave. In the most general case, polarization is elliptical, meaning that the polarization of the radio waves varies over time. Two special cases are linear polarization (the ellipse collapses into a line) and circular polarization (in which the two axes of the ellipse are equal). In linear polarization the antenna compels the electric field of the emitted radio wave to a particular orientation. Depending on the orientation of the antenna mounting, the usual linear cases are horizontal and vertical polarization. In circular polarization, the antenna continuously varies the electric field of the radio wave through all possible values of its orientation with regard to the Earth's surface. Circular polarizations, like elliptical ones, are classified as right-hand polarized or left-hand polarized using a "thumb in the direction of the propagation" rule. Optical researchers use the same rule of thumb, but pointing it in the direction of the emitter, not in the direction of propagation, and so are opposite to radio engineers' use.

In practice, regardless of confusing terminology, it is important that linearly polarized antennas be matched, lest the received signal strength be greatly reduced. So horizontal should be used with horizontal and vertical with vertical. Intermediate matchings will lose some signal strength, but not as much as a complete mismatch. Transmitters mounted on vehicles with large motional freedom commonly use circularly polarized antennas so that there will never be a complete mismatch with signals from other sources.

Transmission and reception

All of the antenna parameters are expressed in terms of a transmission antenna, but are identically applicable to a receiving antenna, due to reciprocity. Impedance, however, is not applied in an obvious way; for impedance, the impedance at the load (where the power is consumed) is most critical. For a transmitting antenna, this is the antenna itself. For a receiving antenna, this is at the (radio) receiver rather than at the antenna. Tuning is done by adjusting the length of an electrically long linear antenna to alter the electrical resonance of the antenna.

Antenna tuning is done by adjusting an inductance or capacitance combined with the active antenna (but distinct and separate from the active antenna). The inductance or capacitance provides the reactance which combines with the inherent reactance of the active antenna to establish a resonance in a circuit including the active antenna. The established resonance being at a frequency other than the natural electrical resonant frequency of the active antenna. Adjustment of the inductance or capacitance changes this resonance.

Antennas used for transmission have a maximum power rating, beyond which heating, arcing or sparking may occur in the components, which may cause them to be damaged or destroyed. Raising this maximum power rating usually requires larger and heavier components, which may require larger and heavier supporting structures. This is a concern only for transmitting antennas, as the power received by an antenna rarely exceeds the microwatt range.

Antennas designed specifically for reception might be optimized for noise rejection capabilities. An antenna shield is a conductive or low reluctance structure (such as a wire, plate or grid) which is adapted to be placed in the vicinity of an antenna to reduce, as by dissipation through a resistance or by conduction to ground, undesired electromagnetic radiation, or electric or magnetic fields, which are directed toward the active antenna from an external source or which emanate from the active antenna. Other methods to optimize for noise rejection can be done by selecting a narrow bandwidth so that noise from other frequencies is rejected, or selecting a specific radiation pattern to reject noise from a specific direction, or by selecting a polarization different from the noise polarization, or by selecting an antenna that favors either the electric or magnetic field.

For instance, an antenna to be used for reception of low frequencies (below about ten megahertz) will be subject to both man-made noise from motors and other machinery, and from natural sources such as lightning. Successfully rejecting these forms of noise is an important antenna feature. A small coil of wire with many turns is more able to reject such noise than a vertical antenna. However, the vertical will radiate much more effectively on transmit, where extraneous signals are not a concern.

NETWORKING CABLING

What is Network Cabling?

Cable is the medium through which information usually moves from one network device to another. There are several types of cable which are commonly used with LANs. In some cases, a network will utilize only one type of cable, other networks will use a variety of cable types. The type of cable chosen for a network is related to the network's topology, protocol, and size. Understanding the characteristics of different types of cable and how they relate to other aspects of a network is necessary for the development of a successful network.

The following sections discuss the types of cables used in networks and other related topics.

* Unshielded Twisted Pair (UTP) Cable
* Shielded Twisted Pair (STP) Cable
* Coaxial Cable
* Fiber Optic Cable
* Cable Installation Guides
* Wireless LANs

Unshielded Twisted Pair (UTP) Cable

Twisted pair cabling comes in two varieties: shielded and unshielded. Unshielded twisted pair (UTP) is the most popular and is generally the best option for school networks (See fig. 1).

Fig.1. Unshielded twisted pair

The quality of UTP may vary from telephone-grade wire to extremely high-speed cable. The cable has four pairs of wires inside the jacket. Each pair is twisted with a different num ber of twists per inch to help eliminate interference from adjacent pairs and other electrical devices. The tighter the twisting, the higher the supported transmission rate and the greater the cost per foot. The EIA/TIA (Electronic Industry Association/Telecommunication Industry Association) has established standard s of UTP and rated six categories of wire (additional categories are emerging).

Categories of Unshielded Twisted Pair

Unshielded Twisted Pair Connector

The standard connector for unshielded twisted pair cabling is an RJ-45 connector. This is a plastic connector that looks like a large telephone-style connector (See fig. 2). A slot allows the RJ-45 to be inserted only one way. RJ stands for Registered Jack, implying that the connector follows a standard borrowed from the telephone industry. This standard designates which wire goes with each pin inside the connector.

Fig. 2. RJ-45 connector

Shielded Twisted Pair (STP) Cable

Although UTP cable is the least expensive cable, it may be susceptible to radio and electrical frequency interference (it should not be too close to electric motors, fluorescent lights, etc.). If you must place cable in environments with lots of potential interference, or if you must place cable in extremely sensitive environments that may be susceptible to the electrical current in the UTP, shielded twisted pair may be the solution. Shielded cables can also help to extend the maximum distance of the cables.

Shielded twisted pair cable is available in three different configurations:

1. Each pair of wires is individually shielded with foil.
2. There is a foil or braid shield inside the jacket covering all wires (as a group).
3. There is a shield around each individual pair, as we ll as around the entire group of wires (referred to as double shield twisted pair).

Coaxial Cable

Coaxial cabling has a single copper conductor at its center. A plastic layer provides insulation between the center conductor and a braided metal shield (See fig. 3). The metal shield helps to block any outside interference from

Fig. 3. Coaxial cable

Although coaxial cabling is difficult to install, it is highly resistant to signal interference. In addition, it can support greater cable lengths between network devices than twisted pair cable. The two types of coaxial

Thin coaxial cable is also referred to as thinnet. 10Base2 refers to the specifications for thin coaxial cable carrying Ethernet signals. The 2 refers to the approximate maximum segment length being 200 meters. In actual fact the maximum segment length is 185 meters. Thin coaxial cable has been popular in Thick coaxial cable is also referred to as thicknet. 10Base5 refers to the specifications for thick coaxial cable carrying Ethernet signals. The 5 refers to the maximum segment length being 500 meters. Thick coaxial cable has an extra protective plastic cover that helps keep moisture away from the center conductor. This makes thick coaxial a great choice when running longer lengths in a linear bus network. One disadvantage of thick coaxial is that it does

Coaxial Cable Connectors

The most common type of connector used with coaxial cables is the Bayone-Neill-Concelman (BNC) connector (See fig. 4). Different types of adapters are available for BNC connectors, including a T-connector, barrel connector, and terminator. Connectors on the cable are the weakest points in any network. To help avoid problems with your network, always use the BNC connectors that crimp, rather

Fig. 4. BNC connector

Fiber Optic Cable

Fiber optic cabling consists of a center glass core surrounded by several layers of protective materials (See fig. 5). It transmits light rather than electronic signals eliminating the problem of electrical interference. This makes it ideal for certain environments that contain a large amount of electrical interference. It has also made it the standard for connecting networks between

Fiber optic cable has the ability to transmit signals over much longer distances than coaxial and twisted pair. It also has the capability to carry information at vastly greater speeds. This capacity broadens communication possibilities to include services such as video conferencing and interactive services. The cost of fiber optic cabling is comparable to copper cabling; however, it is

The center core of fiber cables is made from glass or plastic fibers (see fig 5). A plastic coating then cushions the fiber center, and kevlar fibers help to strengthen the cables and prevent breakage. The outer insulating jacket made of teflon or PVC.

Fig. 5. Fiber optic cable

There are two common types of fiber cables -- single mode and multimode. Multimode cable has a larger diameter; however, both cables provide high bandwidth at high speeds. Single mode can provide more distance, but it is more expensive.

Ethernet Cable Summary

Know Your Wireless Network Adapter

So that the computer can be connected by a network or network, means the computer will need a special tool. Special tool designed to modify, send, and receive data to and from the network. This tool is commonly called a Network Adapter.

How about a wireless network or wireless network? Same. So that the computer can capture, identify, transmit, and receive data to and from the network without wires aka wireless network, means a computer needs a wireless network adapter.

Well, if you want your computer can detect, then join the existing wireless networks around, it means you need a wireless network adapter. In the wireless adapter, there is a transmitter that serves to transmit radio signals, and receiver which receives the waves or signals.

If by chance your laptop already has built-in wireless adapter, and you feel quite satisfied with the capabilities it possesses, then you probably do not need to buy a new wireless adapter. But, if by chance your laptop or computer memilkinya yet, then you need to buy it.

Out there, there are many kinds, types, brands, and the form of wireless adapters. Capabilities, strengths, weaknesses, and quality also vary. To seek and find the most appropriate wireless adapter with the desire, then you first need to recognize other forms of wireless adapters.

Forms Wireless Adapter

Wireless adapters are generally placed in one of the port input / output (I / O port) on your computer. For example, in expansion card slot, or in-socket embedded on the motherboard, or on a PCMCIA socket, or also on the USB socket. Where and how the wireless card is issued, depending on the shape.

Of course, each form of wireless adapters have advantages and disadvantages. To find out where the most appropriate form for you, probably will depend also on the type of computer you use.

For example, wireless adapater shaped PC Card is usually best suited for laptops. Medium USB adapter, usually most convenient to your Desktop. But, of course it does not have to. You're still free to choose the form of a wireless adapter that you want. As long as your computer provides the necessary slots.

Internal adapters

Almost all new laptops have a module output on the mini-PC wireless adapter Cardnya. This module is in place it directly on the motherboard. An antenna, as well as in included with him. The aim, among others, to add convenience and comfort at laptop users.

With a wireless adapter that attached directly on the motherboard, so laptop users do not have to bother carrying it along with the laptop wireless adapter. This is also in order to minimize the risk of losing the wireless adapter. For example you forgot, or left behind. The disadvantage?

Just one, because the adapter is attached on the motherboard, making the adapter can not be lifted and moved. To what moved? For example when I want to use the wireless adapter on your laptop or another desktop.

Laptops that include a wireless adapter module in the motherboard, generally include a button to turn on and turn off this function. Use, among others, to maintain security and save battere. Well, if it turns your laptop has an internal adapter, try to find the button, and use.

If you're not want to use wireless, then it should function is turned off. That's to prevent your computer is not infiltrated by people via the wireless network. Also to save battere. Also Do not forget to turn it on again, as you want to access wireless networks.

PC Cards

Although mu latop has no internal wireless adapter, you do not have to be sad and disappointed. You still can detect and access the wireless network with your laptop, by way of buying a wireless adapter in the form of PC Cards. Then place them on a PCMCIA card slot.

What about brand choices? Do not worry, nearly all of the Wireless equipment manufacturers produce this type of adapter. In addition to the practical shape, weight is not too burdensome. Which one, two it was a factor in the desire by most laptop users.

How about battere? Is when not in use, the PC Cards seboros Internal Adapter?

Nope, experts say that when not in use, the PC Cards are not seboros Internal Adapter.

But for the sake of saving, of course you can remove it when not in use.

According to the info, the PC Cards are divided into two types. The first type is called Original Standard. Referred to as PCMCIA type older models, because they still use the data transfer speed 16-bit, and it only supports 802.11b wireless networking standard. This type is found on the old laptop output.

As for the second type, has a transfer speed 32 bit, because it already supports CardBus features. This type of PC Cards capable of detecting and accessing 802.11a/g/n wireless networking standard. Laptops are produced in the 1990s and above, supports PC Cards usually have this type.

As for laptops in 2006 or more output, usually capable of using both types of PC Cards earlier. Laptops latest output, generally using a special slot called ExpressCard. Physically, the slot of this type uses a different card types, and is not compatible with the two types above.

USB Adapters

For now, the wireless adapter in place on the USB slot is probably the best alternative to access wireless networks. Why? Because, almost all computer output in 1999 and above, either a laptop or desktop, would have been equipped with a USB slot.

This type of wireless adapter, both which were placed directly, or another connected with the cable, generally also been equipped with a built-in antenna. In addition, its small and lightweight, making it impractical to be moved or taken together with the computer.


This wireless USB adapter, comes with a variety of shapes and sizes. Dimilkipun capabilities and features vary. Of the most simple, to the futuristic.

That is partly because each manufacturer has their own philosophy and target market. Starting from the general user, techno-phobia, until techno mania.

And, because antennanya larger and easier to manipulate, you can expect better performance than the internal adapters.

Besides adapter that is shaped like the picture 2, there is also a USB adapter that looks very similar to the Flash Drive or Flash Disk.

Because the shape and smaller size, the USB adapter of this type generally have a transmitter and a receiver with a lower capability than PC Cards, or USB adapters are shown in Figure 2.

That of course would affect its ability in terms of capturing and sending wireless signals. This type of USB adapters often fail to detect and capture the signal. As a result, communication via wireless is often disconnected.


Expansion Cards For Desktop Computers

This type of wireless adapter, shaped similar to what cards other expansion. For example sound or video card. Placement mode is the same. Namely in the insert contained in a special slot on the motherboard. Consider the image below. This is one example of the type of wireless adapter cards expansion.

Although looks different, but many types of these adapters are actually the same adapter in place on the PCMCIA slots, and then add expansion cards that fit with slots on the motherboard.

If by chance you're buying this type adapter with a built-in antenna, meaning you do not need to look for an external antenna with a connector that fits. But if it turns out there is no bulit-in antenna?

Means you should look for an external antenna connectors that fit. Yep, indeed troublesome. Apart from still having to deal with the cable mengabel, several other problems also often encountered. For example, the signal is lost or disrupted by a computer casing, or other device located in the vicinity.

With all the difficulties, it does not mean that this type of adapter can not work properly. Adapter type is still capable of working equally well with other types of adapters. Especially if you master the things associated with wireless technology. Example of what often become bullies signal, etc.

But if you do not want to bother, the Wireless USB adapter may be more appropriate for you.

Wireless network buying guide

Right network

With so many possible ways to build a network, it pays to home in on the solution that best suits your needs before you buy. These user profiles will start you off in the right direction.

Basic Home Network

You can get ample bandwidth for sharing a broadband Internet connection without spending much. In most cases, even the slowest existing wireless gear is faster than the speed at which a cable or DSL modem connects to the Internet.

It's getting more and more common that the service provider would provide you with a simple wireless router that also works as a broadband modem. Nonetheless, here is the break down of what you will need if you don't already have anything at all.

Note that a lot of new computer, especially laptops and Netbooks, already have a wireless adapter built-in. For those that don't, the fastest way to add wireless capability to them is via a USB adapter. There are also internal PCI add-in wireless card for desktops that you can get. However, installing them would require opening the computer.

This is the cheapest setup. A lot of time, if the provider gives you a free modem/wireless router combo, this might not even cost you anything at all. If the service provider gives you only a modem, only a basic wireless router is needed. Examples of these routers are the Linksys WRT160N, the Netgear WNDR2000, the D-Link DIR-615 or the TP-Link TL-WR741ND.

Home Office Network

If you use your home as an office, you need a faster router (both wired and wireless speeds) with good security features. An office generally has more data travel around within the local network and therefore a router with Gigabit Ethernet capability is a must. This is the wired connection that caps at 1000Mbps. It should also have Wireless-N (802.11n) instead of the Wireless-G that caps at only 54Mbps. Wireless-N genrally offers speed up to 300Mbps, (though going forward they will offer even faster wireless speed). The router should also offer advance networking features that allows for accessing your local network securely from the Internet. Examples of these features, depending on what you need varies from Port Forwarding, Firewall and (Virtual Private Network capability.)

Some existing business routers don't have the built-in wireless functionality. In this case you can add a wireless access point to the router to make the network wireless capable. Make sure you get a Wireless-N (802.11n) access point. With network with lots of complicated settings, this is a faster way than replacing the existing router with a wireless one.

Sharing printer and files between network computers are common tasks. There are many routers that have built-in print serving capability, such as the Linksys WRT610n, or the Apple Airport Extreme Base Station. With this type of routers, you can plug a USB printer to them and the printer will be available to all computers in the network. It's best, however, that you get a printer that has built-in network capability. Most new printers, both laser and inkjet, have the networking option. Some of them even have built-in wireless networking option.

The simplest and also the most affordable way to share data between network computers is via a Network Attached Storage (NAS) server. A NAS server is much like a regular server minus the monitor, mouse and keyboard. In recent years, NAS server have gotten so advanced that apart from being a centralized storage device for file sharing, media streaming and backups, some of them can also be used as a print server, surveillance station, FPT server and so on. Most NAS servers also offer the ability to be accessible remotely via the Internet. Examples of best NAS server for small business and home office environments are the Synology DS209+, the QNAP TS239 Pro , or the HP MediaSmart EX495.

Online Gaming and Home Entertainment

For most online gamers, a Basic Home Network would do the job just fine. However, game consoles, like the Xbox 360 or the PlayStation 3, can do a lot more than just games. They are frequently used as a TV Set Top boxes that play streamed media from a NAS server or a computer in the network. And you want a fast network when it comes to streaming high definition contents, especially when you want to stream to multiple clients.

If you connect your streaming clients to the network via cable, make sure you have a Gigabit router. Even if the Set Top boxes don't support Gigabit Ethernet, this helps when more than one clients stream digital content from the same source.

If you connect clients via wireless connections, other than using a Gigabit Wireless-N router, there's an option of using a true dual-band routers. A true dual-band router can support Wireless-N in both 2.4Ghz and 5Ghz frequencies. As the 2.4Ghz frequency is shared with other home appliances such as Bluetooth devices and cordless phone, the 5Ghz frequency devices tend to offer better throughput. To take advantage of the 5Ghz frequency, both the router and the client have to support this band. In reality however, if you live in a neighborhood where there are not of wireless access points, you will do just fine with a single band 2.4Ghz Wireless-N router.

You can always turn a game console (or any Ethernet-ready network devices) into wireless by using a wireless bridge (also known as wireless gaming adapter). A bridge connect to a device via the Ethernet port, much like a USB wireless adapter connects to a computer (and add wireless functionality to it) via a USB port.

It doesn't matter how great your goods are, it's always good to spice up your business with free Internet Access. The good news is it doesn't cost much for this. You just need a good Wireless-N router that offers along range and the Guest Networking feature. Guest Networking is especially helpful in case you want to use the same router for your local office and keep it secure. The feature (also known as Guest Zone) allows for creating a separate wireless network that allows access to the Internet but block access to your local resources such as your computers or printers. Guest Networking also has the option of blocking wireless clients from "seeing" one another, meaning a person with bad intention can't hack into other devices that connect to your Guess Zone.

There are many routers on the market that offer Guest networking. Examples are D-Link DIR 855, D-Link DIR-825, or Linksys WRT610n, or Apple Airport Extreme Base Station.

Hot Spot provider

You don't need to be a rocket scientist to connect two or more houses wirelessly or to share an Internet connection with an entire building or neighborhood. Whether your objectives are philanthropic or commercial, building a hot spot can be done for less than the cost of a high-end notebook.

Powerline Network Adapter

The firm offered a variety of HomePlug-based Ethernet-to-Power line communication products:

PLTE200 – Powerline Network Adapter
PLTS200 – Powerline 4-Port Network Adapter
PLTK300 – Powerline Network Kit
PLE300 – Powerline AV Network Adapter
PLS300 – Powerline AV 4-Port Network Adapter
PLK300 – Powerline AV Network Kit

Wireless Home Audio

Network Attached Storage

NSLU2 : The NSLU2 is a network attached storage device with 8 MB of flash memory, 32MB of SDRAM, a 100Mb Ethernet port, and two USB ports. The NSLU2 was discontinued in 2008, but is still in demand because of the numerous enhancements developed by open-source community projects.

Network Media Hub

The Media Hub 300 and 400 series are network attached storage devices that allow users to share digital media across a network. Once the Media Hub is connected to the network, it searches for media content residing within the network and aggregates it into one centralized location, including all UPnP devices found. The Built-in Media Reader can directly import photos from compact Flash devices, SD cards and memory sticks without the need of a computer. Memory capacity options are 500GB or 1TB, with an extra empty bay.

The Media Hub's GUI gives a holistic view of the media located on the network regardless of where the actual file is located. Albums are consolidated, artwork, track numbers, and other metadata are downloaded, and all information can be sorted by a variety of different criteria. Included is Automated Backup Software that helps preserve the data through continuous storage backup.

LinkSys ADSL modem AM300 backside showing ethernet, USB, and phone line ports.

USB Wireless

WUSB54G series of USB wireless adapters use the Ralink RT2500 chipset. They support the 802.11b and 802.11g wireless network standards, and have Open Source drivers available for Linux. Drivers are also available for use on Macintosh systems. Only the Version 4 contains the Ralink chipset. Modification of the driver to work with Macintosh was discovered by Kramer2k.

LinkSys ADSL modem AM300

WAG200G has a 211MHz AR7 MIPS32 CPU with 4 MB of flash memory and 16MB of DRam on the PCB. The WAG200G measures 5.5×5.5×1.25 inches (14×14×3.2 cm) (W×H×D) and weighs .77 pounds (.35 kg). The WAG200G all-in-one device functions as a high speed ADSL2+ Modem, a Wireless G Access Point, router and 4-port Ethernet switch. The built-in wireless Access Point function complies with the specifications of the 802.11g standard, which offers transfer speeds of up to 54 Mbit/s.

It is also backwards compatible with 802.11b devices at speeds of 11 Mbit/s. The Access Point can support the connection of up to 32 wireless devices. It also offers 4 built-in 10/100 RJ-45 ports to connect Ethernet-enabled computers, print servers and other devices

Linksys

Linksys by Cisco, commonly known as Linksys, was a major provider of home and small office network products, founded in 1988 and acquired by Cisco Systems in 2003[1]. Linksys manufactured broadband and wireless routers, consumer and small business grade Ethernet switching, VoIP equipment, wireless internet video camera, AV products, network storage systems, and other products. Linksys products were widely available in North America off-the-shelf from both consumer electronics stores (CompUSA and Best Buy), internet retailers, and big-box retail stores (WalMart). Linksys' significant competition as an independent firm were D-Link and NetGear, the latter for a time being a brand of Cisco competitor Nortel.

In 2007, Cisco CEO John Chambers described the longterm plan to kill the independent Linksys brand: "It will all come over time into a Cisco brand. The reason we kept Linksys' brand because it was better known in the US than even Cisco was for the consumer. As you go globally there's very little advantage in that." From 2008, all Linksys products sold were packaged and branded as "Linksys by Cisco"; some former Linksys products were merged into the "Valet" brand (albeit with a large Cisco logo and smaller Linksys name still on the product). The formerly-independent Linksys website presently redirects to Cisco's. Small-business inquiries into former Linksys products are directed to Cisco's products and reseller network.

Cisco Aironet 350 Wireless LAN Client Adapter - Cisco Systems

Wireless client adapters are the key to adding mobility and flexibility to an enterprise-increasing productivity by enabling users to have network and Internet access anywhere within a building without the limitation of wires. The Cisco Aironet 350 Series Client Adapters are a complement to Aironet 350 Series infrastructure devices, providing an enterprise-ready solution that combines mobility with the performance, security, and manageability that people have come to expect from Cisco. Wireless client adapters connect a variety of devices to a wireless network either in ad hoc peer-to-peer mode or in infrastructure mode with APs. Available in PC Card (PCMCIA) and Peripheral Component Interconnect (PCI) form factors, Cisco Aironet 350 Series Client Adapters quickly connect desktop and mobile computing devices wirelessly to all network resources. With this product, you can instantly add new employees to the network, support temporary workgroups, or enable Internet access in conference rooms or other meeting spaces.

Wireless Access for Notebooks, Desktops, and Tower PCs

Give your computer network access from anywhere in the building without the cost and hassle of running Ethernet cables. One of the Cisco Small Business Wireless Adapters, the WUSB200 Wireless-G USB Network Adapter with RangeBooster uses a single USB port give high-quality wireless access to both notebook and desktop computers. The device's RangeBooster technology nearly doubles the connection range of a typical Wireless-G product and increases throughputs by up to 35 percent.

Unlike ordinary wireless technologies that are confused by signal reflections, RangeBooster utilizes two smart receivers at each end to detect and decode reflected signals at distances where standard technologies give up.

Additional features of the Cisco WUSB200 Wireless-G Business USB Adapter include:

• Advanced wireless security supporting WEP, WPA, and WPA2 encryption
• Interoperation with standard Wireless-G and Wireless-B wireless protocols
• Wireless security monitoring that alerts you to possible intruders and network vulnerabilities when used in conjunction with a Cisco WAP200 Access Point

Wireless network interface card IEEE 802.11

IEEE 802.11 is a set of standards carrying out wireless local area network (WLAN) computer communication in the 2.4, 3.6 and 5 GHz frequency bands. They are created and maintained by the IEEE LAN/MAN Standards Committee (IEEE 802). The base current version of the standard is IEEE 802.11-2007.

The 802.11 family includes over-the-air modulation techniques that use the same basic protocol. The most popular are those defined by the 802.11b and 802.11g protocols, which are amendments to the original standard. 802.11-1997 was the first wireless networking standard, but 802.11b was the first widely accepted one, followed by 802.11g and 802.11n. Security was originally purposefully weak due to export requirements of some governments,[1] and was later enhanced via the 802.11i amendment after governmental and legislative changes. 802.11n is a new multi-streaming modulation technique. Other standards in the family (c–f, h, j) are service amendments and extensions or corrections to the previous specifications.

802.11b and 802.11g use the 2.4 GHz ISM band, operating in the United States under Part 15 of the US Federal Communications Commission Rules and Regulations. Because of this choice of frequency band, 802.11b and g equipment may occasionally suffer interference from microwave ovens, cordless telephones and Bluetooth devices. Both 802.11 and Bluetooth control their interference and susceptibility to interference by using spread spectrum modulation. Bluetooth uses a frequency hopping spread spectrum signaling method (FHSS), while 802.11b and 802.11g use the direct sequence spread spectrum signaling (DSSS) and orthogonal frequency division multiplexing (OFDM) methods, respectively. 802.11a uses the 5 GHz U-NII band, which, for much of the world, offers at least 19 non-overlapping channels rather than the 3 offered in the 2.4 GHz ISM frequency band.[2] Better or worse performance with higher or lower frequencies (channels) may be realized, depending on the environment.

The used segment of the radio frequency spectrum varies between countries. In the US, 802.11a and 802.11g devices may be operated without a license, as allowed in Part 15 of the FCC Rules and Regulations. Frequencies used by channels one through six (802.11b) fall within the 2.4 GHz amateur radio band. Licensed amateur radio operators may operate 802.11b/g devices under Part 97 of the FCC Rules and Regulations, allowing increased power output but not commercial content or encryption.[3]


Current 802.11 standards define "frame" types for use in transmission of data as well as management and control of wireless links.

Frames are divided into very specific and standardized sections. Each frame has a MAC header, payload and FCS. Some frames may not have payload portion. First 2 bytes of MAC header is a frame control field that provides detailed information about the frame. The sub fields of the frame control field is presented in order.

* Protocol Version: It is two bits in size and represents the protocol version. Currently used protocol version is zero. Other values are reserved for future use.

* Type: It is two bits in size and helps to identify the type of WLAN frame. Control, Data and Management are various frame types defined in IEEE 802.11.

* Sub Type: It is four bits in size. Type and Sub type are combined together to identify the exact frame.

* ToDS and FromDS: Each are one bit in size. They indicate whether a data frame is headed for a distributed system. Control and management frames set these values to zero. All the data frames will have one of these bits set. However communication within an IBSS network always set these bits to zero.

* More Fragment: The More Fragmentation bit is set most notably when higher level packets have been partitioned and will be set for all non-final sections. Some management frames may require partitioning as well.

* Retry: Sometimes frames require retransmission, and for this there is a Retry bit which is set to one when a frame is resent. This aids in the elimination of duplicate frames.

* Power Management: The Power Management bit indicates the power management state of the sender after the completion of a frame exchange. Access points are required to manage the connection and will never set the power saver bit.

* More Data: The More Data bit is used to buffer frames received in a distributed system. The access point uses this bit to facilitate stations in power saver mode. It indicates that at least one frame is available and addresses all stations connected.

* WEP: The WEP bit is modified after processing a frame. It is toggled to one after a frame has been decrypted or if no encryption is set it will have already been one.

* Order: This bit is only set when the "strict ordering" delivery method is employed. Frames and fragments are not always sent in order as it causes a transmission performance penalty.

The next two bytes are reserved for the Duration ID field. This field can take one of three forms: Duration, Contention-Free Period (CFP), and Association ID (AID).

An 802.11 frame can have up to four address fields. Each field can carry a MAC address. Address 1 is the receiver, Address 2 is the transmitter, Address 3 is used for filtering purposes by the receiver.

* The Sequence Control field is a two-byte section used for identifying message order as well as eliminating duplicate frames. The first 4 bits are used for the fragmentation number and the last 12 bits are the sequence number.
* An optional two-byte Quality of Service control field which was added with 802.11e.
* The Frame Body field is variable in size, from 0 to 2304 bytes plus any overhead from security encapsulation and contains information from higher layers.
* The Frame Check Sequence (FCS) is the last four bytes in the standard 802.11 frame. Often referred to as the Cyclic Redundancy Check (CRC), it allows for integrity check of retrieved frames. As frames are about to be sent the FCS is calculated and appended. When a station receives a frame it can calculate the FCS of the frame and compare it to the one received. If they match, it is assumed that the frame was not distorted during transmission.[15]

Management Frames allow for the maintenance of communication. Some common 802.11 subtypes include:

* Authentication frame: 802.11 authentication begins with the WNIC sending an authentication frame to the access point containing its identity. With an open system authentication the WNIC only sends a single authentication frame and the access point responds with an authentication frame of its own indicating acceptance or rejection. With shared key authentication, after the WNIC sends its initial authentication request it will receive an authentication frame from the access point containing challenge text. The WNIC sends an authentication frame containing the encrypted version of the challenge text to the access point. The access point ensures the text was encrypted with the correct key by decrypting it with its own key. The result of this process determines the WNIC's authentication status.
* Association request frame: sent from a station it enables the access point to allocate resources and synchronize. The frame carries information about the WNIC including supported data rates and the SSID of the network the station wishes to associate with. If the request is accepted, the access point reserves memory and establishes an association ID for the WNIC.
* Association response frame: sent from an access point to a station containing the acceptance or rejection to an association request. If it is an acceptance, the frame will contain information such an association ID and supported data rates.
* Beacon frame: Sent periodically from an access point to announce its presence and provide the SSID, and other parameters for WNICs within range.
* Deauthentication frame: Sent from a station wishing to terminate connection from another station.
* Disassociation frame: Sent from a station wishing to terminate connection. It's an elegant way to allow the access point to relinquish memory allocation and remove the WNIC from the association table.
* Probe request frame: Sent from a station when it requires information from another station.
* Probe response frame: Sent from an access point containing capability information, supported data rates, etc., after receiving a probe request frame.
* Reassociation request frame: A WNIC sends a reassociation request when it drops from range of the currently associated access point and finds another access point with a stronger signal. The new access point coordinates the forwarding of any information that may still be contained in the buffer of the previous access point.
* Reassociation response frame: Sent from an access point containing the acceptance or rejection to a WNIC reassociation request frame. The frame includes information required for association such as the association ID and supported data rates.

Control frames facilitate in the exchange of data frames between stations. Some common 802.11 control frames include:

* Acknowledgement (ACK) frame: After receiving a data frame, the receiving station will send an ACK frame to the sending station if no errors are found. If the sending station doesn't receive an ACK frame within a predetermined period of time, the sending station will resend the frame.
* Request to Send (RTS) frame: The RTS and CTS frames provide an optional collision reduction scheme for access point with hidden stations. A station sends a RTS frame to as the first step in a two-way handshake required before sending data frames.
* Clear to Send (CTS) frame: A station responds to an RTS frame with a CTS frame. It provides clearance for the requesting station to send a data frame. The CTS provides collision control management by including a time value for which all other stations are to hold off transmission while the requesting stations transmits.

Data frames carry packets from web pages, files, etc. within the body.

Wireless network interface card

A wireless network interface controller (WNIC) is a network card which connects to a radio-based computer network, unlike a regular network interface controller (NIC) which connects to a wire-based network such as token ring or ethernet. A WNIC, just like a NIC, works on the Layer 1 and Layer 2 of the OSI Model. A WNIC is an essential component for wireless desktop computer. This card uses an antenna to communicate through microwaves. A WNIC in a desktop computer usually is connected using the PCI bus. Other connectivity options are USB and PC card. Integrated WNICs are also available, (typically in Mini PCI/PCI Express Mini Card form).

Modes of operation

Infrastructure mode

In an infrastructure mode network the WNIC needs an access point: all data is transferred using the access point as the central hub. All wireless nodes in an infrastructure mode network connect to an access point. All nodes connecting to the access point must have the same service set identifier (SSID) as the access point, and if the access point is enabled with WEP they must have the same WEP key or other authentication parameters.

Ad-hoc mode

In an ad-hoc mode network the WNIC does not require an access point, but rather can directly interface with all other wireless nodes directly. All the nodes in an ad-hoc network must have the same channel and SSID.

Specifications

WNICs are designed around the IEEE 802.11 standard which sets out low-level specifications for how all wireless networks operate. Earlier interface controllers are usually only compatible with earlier variants of the standard, while newer cards support both current and old standards.

Specifications commonly used in marketing materials for WNICs include:

* Wireless data transfer rates (measured in Mbit/s); these range from 2 Mbit/s to 54 Mbit/s.[4]
* Wireless transmit power (measured in dBm)
* Wireless network standards (may include standards such as 802.11b, 802.11g, 802.11n, etc.) 802.11g offers data transfer speeds equivalent to 802.11a – up to 54 Mbit/s – and the wider 300-foot (91 m) range of 802.11b, and is backward compatible with 802.11b.

Range

Wireless range may be substantially affected by objects in the way of the signal and by the quality of the antenna. Large electrical appliances, such as a refrigerators, fuse boxes, metal plumbing, and air conditioning units can impede a wireless network signal. The theoretical maximum range is only reached under ideal circumstances and true effective range is typically about half of the theoretical range.[4] Specifically, the maximum throughput speed is only achieved at extremely close range (less than 25 feet (7.6 m) or so); at the outer reaches of a device's effective range, speed may decrease to around 1 Mbit/s before it drops out altogether. The reason is that wireless devices dynamically negotiate the top speed at which they can communicate without dropping too many data packets.

Windows 7 Network Card Configuration

Let’s talk about Windows 7 network card (network adapter) configuration here, so that you could connect to Ethernet home network with wired connection. I would assume you have already configured network router correctly, and is ready to connect Windows 7 computer to this network by connecting computer’s network adapter to router’s LAN port with network cable.

Network Card Driver Installation

First you need to make sure you have installed Windows 7 network card driver. Without installing the driver, your network card will not work. If you plug in the network card the first time to the computer and boot up the Windows 7, the system will detect new hardware and prompt you to install the driver, you can then use the driver installation CD or the driver downloaded from vendor website to finish the installation. Sometimes Windows 7 will detect the card and install the driver automatically if it’s supported.

You need to check the driver status to make sure it works well after the driver installation, take a look on this network card driver status checking article if you are not sure how to do it.

TCP/IP Configuration

TCP/IP configuration in Windows 7 network card!! This is the most important part of network card configuration in Windows 7. You must configure the network card, so that this computer can communicate with other computers or network devices properly. You will need to have TCP/IP protocol and other Windows network items installed in order to make it work correctly.

This is how to configure it:

1) Go to Start and click on Control Panel.

2) Proceed to click View network status and tasks in Control Panel window.

3) Network and Sharing Center window will appear, then click Change adapter settings.

Note: Please note this widows will show Local Area Connection as access type if you have connected the computer to router with network cable.

4) Network Connections window will appear. Here you can right click on the network card that you wish to configure and click Properties.

5) In the Local Area Connection Properties, you need to have following items installed and enabled:

Client for Microsoft Networks – Allow your computer to access resources in a Microsoft network.

File and Printer Sharing for Microsoft Networks – Allow your computer to share files and printers in Microsoft network.

Internet Protocol Version 4 (TCP/IPv4) – The protocol that enables your computer to talk to other computers in your network. You need to specify IP address, netmask, gateway and other network information for it to work correctly. If you have configured DHCP setting on router, configure each computer to obtain IP address automatically. If you plan to assign IP address manually on each computer, assign the IP address by following your network design, and make sure the IP is unique. Having problem? You can take a look on this IP address and other network configuration in Windows 7 article.

Note: If you plan to use homegroup feature later, don’t disable the Internet Protocol Version 6 (TCP/IPv6) feature.

Link-Layer Topology Discovery Mapper I/O Driver and Link-Layer Topology Discovery Responder - Used to discover and display your home network map. Check this on how to enable Network Discovery in your network.

If you don’t have those specified items installed, click Install… and follow the instructions to install the items which you missed. Finally click OK to close the window.

At this moment, your Windows 7 computer should be connected to home network. Try to ping other computer or router IP, and access to Internet websites.

Network Location Type Setting

Once your computer is connected to home network, you are advised to set the Network Location, so appropriate firewall and security settings will be automatically set on computer.

If your computer is connected to home network, you should set the network location type as home network in Network and Sharing Center window.

Assigning Computer Name and Workgroup

Each computer in your network must be assigned a name and workgroup, so that it’s easy for your identification later. Follow step-by-step instructions here to set computer name and workgroup in Windows 7.

That’s all the Windows 7 network card configuration, after that you can proceed to do simple file sharing or password protected file sharing as you wish.

If you face network connectivity or website access problem, try to use ping tool to troubleshoot network problem.

Checking Network or Wireless Adapter Driver Status in Windows 7

You are advised to check network or wireless adapter driver status in Windows 7 after installing the driver in order to make sure it works well before trying to connect to wired or wireless network. I used to see users facing network connectivity problem due to incorrect or problematic driver problem, so don’t neglect this simple checking.

This is the way to check network or wireless adapter driver status:

1) Go to Start and click on Control Panel.

2) Control Panel window will appear, click Hardware and Sound.

Note: If you view Control Panel by Large Icons or Small Icons, you can just double click the Device Manager.

3) Click on Device Manager in Hardware and Sound window.

4) The Device Manager will appear, then locate and expand Network adapters and right click the network or wireless adapter you want to check, finally click on Properties.

5) The network or wireless adapter properties window will appear, your driver works well if it shows This device is working properly under General tab. You can also manually configure network adapter’s driver parameters under Advanced tab.

Note: If your device does not work well, click on Driver tab to check driver details, update driver, rollback driver, disable driver or uninstall driver.

Home Network, Wireless Network and Computer Networking Made Easy

Do you think it’s hard to set up network? No, it’s actually pretty easy, what you need is some knowledge and right tools..

Here are some benefits for setting up network at home:

1) Share Internet Connection and printer with family members
2) Set up family discussion board or photo database
3) Set up network game party
4) Learn computer and networking knowledge

The most common network is Ethernet, it’s a very popular LAN (Local Area Network) technology due to its inexpensive setup cost and reasonably fast speed.

The speed of an Ethernet can be 10Mbps (Ethernet), 100Mbps (Fast Ethernet) and 1000Mbps (Gigabit Ethernet). Mbps is called Megabits per seconds. From my opinion, 100Mbps speed might be sufficient for your network needs.

The most basic equipments you need for home network are DSL/Cable Internet connection, router and network cards. Furthermore, most of the computers now are equipped with network card.

Note: If you are interested in wireless broadband Internet service, have a look on this wireless broadband setup article (good to be used in an area where DSL/Cable Internet is unavailable).

It's very straight forward, isn't it? So, ready to go?

Wireless Networks Connect Anytime, Anywhere

The Cisco Unified Wireless Network is a unified wired and wireless network solution that cost-effectively addresses the wireless network security, deployment, management, and control issues your enterprise faces. It combines the best elements of wireless and wired networking to deliver secure, scalable wireless networks with a low total cost of ownership.

Maintain your competitive advantage through the freedom and flexibility of a Cisco Unified Wireless Network. A secure, scalable, cost-effective solution, wireless networks offer:

• Anytime, anywhere access to information, promoting collaboration with colleagues, business partners, and customers
• Real-time access to instant messaging, e-mail, and network resources, boosting productivity and speeding business decision making
• Mobility services, such as voice, guest access, advanced security, and location, that help you transform business operations
• Modular architecture that supports 802.11n, 802.11a/b/g, and enterprise wireless mesh for indoor and outdoor locations, while ensuring a smooth migration path to future technologies and services

This powerful solution delivers business-class connectivity that facilitates deployment of innovative applications to simplify business operations and improve productivity.

What Kind of Wireless Networking Adapter Works Best For You?

In the past when we had to plug everything in, plugging in your internet cord or cable was no more hassle than the rest of the wires attached to your computer. As laptops emerged and the mounds of cords became eliminated, something also had to be done with the internet. With everything else portable, it was the only cord preventing complete freedom and mobility.

It seems like a near-miracle now to be able to surf the internet completely cable-free. It wouldn't have been possible without the design of the modern wireless networking adapter. Rather than being imprisoned in an office, internet users now have the freedom to do their work or leisure in the outdoors, or wherever they please.

What Makes it Work? Built-in radio transmitters and receivers are contained within each wireless networking adapter. Your computer is now able to join a wireless LAN, and connect to the internet.

Which Kind Should I Buy? When it comes to purchasing wireless network adapters, you have two options: the PCI or the USB. Your selection depends on which type of computer system you use.

If you have a traditional desktop computer, the PCI wireless adapter is best for you. These add-in cards are made specifically for your computer and fit inside with all the rest of the hardware. Your desktop should have a place for the adapter to go, called a PCI bus.

For a notebook, on the other hand, you'll need a USB wireless adapter. This devise is external rather than internal, and is easily plugged in at the same spot you might put your flash drive or other USB devise. Don't worry - most notebooks have several USB ports for all your needs.

Another option is built-in wireless networking - a feature found in many notebooks today. Small chips are already placed inside your computer and serve as your network adapter. No further installation is required.

To check whether your computer already has wireless networking, click on the Start menu and then check out your network connections. Another way you can look for any networks is by clicking on the set of computers located next to the volume and time on your toolbar. A mysterious external switch (turning the wireless connector on and off) is also a good indicator.

Prime Electronics is an Earth-friendly business that focuses on recycling consumer electronics and replacement parts, including Directv Tivo Remotes, Avaya Phones, Cisco Modules, and Wireless Networking Equipment.

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