Diversity Antenna?
Could anyone give me some doc. or homepage which describe what is the diversity antenna? It is my first time to meet this antenna. However, I have no idea about this. Could anyone explain it or give me some basic information document and allow me to investigate it.
thanks
wccheng
Let's see... i dont have any papers on the topic but i think i can give you a general view of the subjet.
Diversity is used to reduce noise on the receptor, there are two kinds of diversity, frequency and antenna diversity.
Using frecuency diversity, you use two carrier frecuencies to transmit the data and with antenna diversity you use two antennas to recieve the data.
The antennas must be separated aproximately one wavelenght (or it's half wavelenght) from each other since that is the signal gets it maximun power and it's minimal power on those points, is like the sum of a wave in the sea, there are points where the waves come together and double its altitude and there are places where the wave distroy themself. So the idea here is to have always one antenna that captures the best signal possible, the you just pick that antenna to complete the trasnmission, that way you reduce the effect of noise in the transmission.
Try searching for some info on google or yahoo.
Hope this helped
This book is a good book. It is a very standard text book.
Prentice Hall Wireless Communications: Principles & Practice, 2nd Edition by Rappaport
Example of FM Diversity Antenna to understand it
What it is:
A diversity antenna system uses two antennae mounted at different locations on the vehicle and automatically chooses one that provides the better FM radio signal. The driver is therefore less likely to notice static or weak audio signals due to obstructions.
How it works:
Power lines, traffic lights and buildings can cause local areas of weak FM signals. When driving through such areas, a listener might notice decreased volume or increased noise or static often when the vehicle is stopped for a traffic signal. With two antennae, there is a better chance that one will receive a clear signal. A circuit inside the radio automatically chooses the better signal.
Your benefit:
Better FM radio reception.
PL
Nice reference on diversity antennas for handheld terminals:
http://scholar.lib.vt.edu/theses/ava...ricted/ch8.pdf
Hope you find it useful.
Cheers,
Element7k