Motorola PTP 600 series User Manual page 114

Link planning
For minimum error rates on TDM links, the maximum modulation mode should be
limited to 64QAM 0.75.
The values for (BPSK) are static receive sensitivity measurements. The other values
are static receive sensitivity measurements with an AMOD threshold applied. The
AMOD threshold applied is for a benign radio channel.
Modulation mode affects the following:
Sensitivity
Sensitivity is defined as the combined receive input signal level on both horizontal and
vertical inputs that produces a Null BER Error ratio of 3x10-7.
Output Power
The output power is for a centre channel in Region 1. The output power will be
reduced on the edge channels and may vary if different region codes are selected.
AMOD Threshold
The AMOD threshold is the combined receive input signal level on both horizontal and
vertical inputs that results in the link consistently entering the receive modulation
mode under consideration as the signal level is increased.
System Threshold
Thresholds for all modes except BPSK are for the relevant link optimization AMOD
thresholds. System threshold for BPSK is the RPSK receive sensitivity.
Max Link Loss
The maximum link loss for each modulation mode is derived from the AMOD threshold
for that mode (sensitivity threshold for BPSK) and the maximum Region 1 centre
channel output power. The figures assume integral antennas are used, with gain
depending upon frequency band as follows:
•
23 dBi (5.9 GHz, 5.8 GHz and 5.4 GHz)
•
22 dBi (4.8 GHz and 4.9 GHz)
•
21.5 dBi (4.5 GHz)
•
18 dBi (2.5 GHz)
2-12
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Chapter 2 Planning considerations
phn-0896_012v000
Jul 2010