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1st Published, April 2005

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Hi Gain Antenna for Entry Level Wireless.

Antennae come in variety of build and quality, a better Antenna can propagate the signal better.  However better Antennae (or any Antennae that can be installed on regular Wireless Instruments)  are not amplifiers, they can Not boost the power of the transmission.  The Antenna takes the energy from the power amplifier of the instrument's Transmitter and propagates it into the air, if it is a better quality Antenna it would propagate better and might improve the distance.

Antenna can propagate better if the design is matching the impedance and the wave length of the source, or and by making it Uni-Directional and thus concentrate most of the output power in one direction.

The differences in Antennae quality and build is reflected in dbi rating.  Dbi is a relative measure unit, it reflects the Antenna capacity to provide a better signal than a standard dipole antenna that is cut to the measure of 1/4 size wave length of the frequency that it is designed for (or the center of the frequency in case of range).

The default antennae that is usually installed on entry level Wireless hardware is rated 2dbi.  4dbi is better than 2dbi and 12dbi is better than 4dbi.


It is important to understand that the rating of an Antenna does not reflect the exact functional outcome.  If a 2dbi Antenna provides a working Wireless distance of 50 feet.  A 4 dbi Antenna would extend it to 100 feet.


Getting a better designed Omni Directional Antenna (which is usually in the 4-8 dbi range) might improve somewhat indoor propagation, but it is usually a minimal improvement and might results in a gain of few feet.  In an Indoor envioroment there are many obstructions that absorb the Wireless signal and a better Antenna would not provide a signal to the extend that would overcome these absorptions.

If you do have a Wireless connection in a remote room, but it is unstable, or and provide border line functionality, a better Omni directional Antenna might help to stabilize the connection, but it probably will not stretch the distance further more..

Getting a Real Hi Gain Uni-Directional Antenna will work better, since Uni-Directional Antenna concentrate the signal in one direction.  However a Uni-Directional Antenna would restrict the Wireless availability to one specific direction, and thus might be not suitable to cover your designated area.


Uni-Directional Antennae are much more suitable to outdoor bridging.  With a direct line of site and a Good Uni-Directional Antenna you would be able to Bridge Hundreds of feet (might be even few miles if the Antennae are installed on high towers).


Wireless Hardware usually come with the Antenna attached directly to the output plug of the unit.  Some times better propagation might be achieved by placing the Antenna in a better location. To do so you need to have a Wireless unit with a removable external Antenna and you need an Extension Coax cable.  Unlike Network CAT5e cables that can carry the Network Signal for few hundreds feet without significant loses, a typical Coax that is used for 2.4GHz Wireless loses 4db per 10 feet

In other words (as an example) if you take off the 2dbi antenna and install 8dbi Antenna using 20' of coax the total gain is Zero.


Professional installers prefer to install  additional Access Points with the antenna attached directly to it and use CAT5e to connect it to the Network, and thus avoid the use of Coax.


It is preferable to put a better Antenna on the transmitting source (Wireless Router / Access Point) than on the receiving end.  By putting it on the source you can  improve the General coverage.

If you have a stationary Wireless client computer you can enhance its reception by putting a Uni-Directional Antenna pointing toward the source.

To enhance stationary Bridging it is advisable to use a good directional Antenna on both end of the Wireless Bridge.


The best solution to extend the distance of indoor Wireless Network is to extend coverage by adding more transmitters. I.e. Access Point Repeaters, etc.


You can find more about Wireless effective distance in the following pages.


Link to:  Extending the Distance of Entry Level Wireless Network

Link to:  Using a Wireless Cable/DSL Router as a Switch with an Access Point

Link to:  Wirelessly Bridging Home / SOHO Network


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