Port-to-Port Isolation

[Admin 2545]

When an antenna has  2 ports the port-to-port isolation and cross-polarisation discrimination can be specified. Antennas with 2 or more ports are typically used in technologies that deploy MIMO (multiple-input multiple-outputs). MIMO is a technique that is used to improve the data throughput of a system by making use of multiple channels at the same carrier frequency each of which carries separate data. For this reason, the port-to-port isolation and cross-polarisation discrimination are parameters that should be published.

The port-to-port isolation is defined as the ratio between the power fed into one port of the antenna to the power received at the other port. It is therefore an important parameter to consider if the antenna is to be used with a transmitterthat makes use of MIMO. Ideally one would like the two ports to be completely independent (infinite isolation) because then what ever signal is transmitted from one port will not interfere with the signal transmitted from the other port. The lower the isolation, the more interference there will be between the two transmitted signals

 

[Admin 2545]

,,,single patch MiMo..

I think port to port isolation is not good..!!!

 

and 2x2 patch MiMo...

[Admin 2545]

A mimo antenna has two ports, one inputs and one output, by definition. The isolation is a measure of how well the ports are separated from each other in terms of unwanted signal coupling. 30dB isolation is in most cases considered 'high isolation'. Leakage or feed thru is the terminology of the unwanted signal coupling.