Direction vs Omnidirectional Antennas

In: Computers and Technology

Submitted By thejaa2322
Words 346
Pages 2
Compare and contrast the two types of antennas.
Two types of antennas are directional and omnidirectional antennas. Both antennas send signals over a medium. The directional antenna signal in one specific location and is used on in the exterior of building and it points to the inside direction of the building. The oval shape acts as a barrier to keep the signal flowing in one directions and it keeps the signal from distorting or flowing in multiple locations. This means that anyone than needs to access the network, needs to be inside of the building hence, this is reduces any security issues on the network. However the WAN technologies use omnidirectional antennas because it spreads the signals as far as the wavelength can reach. This spreads the network to any neighboring buildings but also pose as a security risk because anyone in the proximity of the wave length can have access to the network. The signal spreads in every direction as compared to the directional antenna that focuses on one direction. The picture below, which was taken from the network textbook, shows the both antennas in addition to the signal flow.

How does 802.11g differ from 802.11b and 802.11a?

802.11b has a range of 2.4GHz and provides only three channels for indoor usage. Each channel however, has up to 11Mbps and when the signal reaches furthers out, it begins to weaken. It is more advanced than the 802.11a because of the broader frequency range and it suffers less attenuation. The only disadvantage is that 802.11b has less speeds than the 802.11a.
The 802.11g differs from this because it is backwards compatible to the 802.11b, each channel has data rate of 54Mbps.

How much overlap should be provided between APs? Why?
The overlap in Aps should be 15% of the desired signal strength because it provides a smooth and transparent roaming from AP to AP. Each AP is set to…...

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