Freq+Space Diversity

[Charlie]

In Pathloss 4, antenna configuration:TR-TRTH or TRTH-TR is defined as for a hybrid diversity configuration which uses frequency diversity in both directions and space diversity at one end of the path only.

In ITU P.530-8 the FD+SD diversity is specified for 2 receivers and 4 receivers separately in calculating outage probability. I used the above antenna configuration for 2 receivers, but I couldn't find any calculation for 4 receivers in Pathloss.

I'll appreciate if anybody can help me with this. Thanks.

Charlie

[Vic Rhys-Williams]

Charlie;

The configuration you describe is Quad Diversity. Antenna configurations should be TXRX-TXRX and configured with nominal SD. In the Worksheets module select Operations Diversity Calculation and specify the frequency diversity difference.

The resulted Worksheet Report will provide the effective receive level and reliability for Quad Diversity for each receiver.

Cheers Vic R-W

[Charlie]

Hi Vic,

Thank you very much for the reply. As a matter of fact, I had tried to use TRDR-TRDR configuration and specify the FD spacing for calculation before I posted the question in the Forum.

Unfortunately, the calculation result was not much different from that of 2-receiver. Moreover, it did not match the hand calculation that I did on the Excel worksheet according to ITU P.530-8 recommendation, either. Any idea?

Regards,
Charlie

[Vic Rhys-Williams]

Charlie;

If you check the help under antenna configurations it will show TXRX-TXRX as two antennas at each site both transmitting and receiving. Most Quad configurations that I have come across transmit one frequency on each antenna with two receivers, one on each receive frequency.

TRDR-TRDR is normally used for space diversity, Where the second antenna is receive only.

Hope this helps. Try it again with TX-RX and see if the results are more in line with your spread sheet.

Cheers.

Vic R-W

[Hossam_El_Meadawy]

Charlie, I guess you are right, there is no 4-Rx configuration in PL4 for the quad diversity calculation, you can only acheive it with 2 Rxs only.
using the TR-TRTH, as the TXRX-TXRX are 4 antennas configuration with no diversity. one antenna Tx and the other is RX.