Example - Motorola PTP 600 Series User Manual

NOTE: There is a small difference between the rates for IP and TDM because there is
fragmentation in TDM (for low priority traffic) which causes the throughput to be reduced buy
approximately 1% compared to the IP mode.

16.1.2 Example

Suppose that the link characteristics are:
x
Product variant = PTP 600 Lite
x
Link Symmetry = 1:1
x
Link Mode Optimization = TDM
x
Modulation Mode = 64QAM 0.92 Dual
x
Channel Bandwidth = 10 MHz
x
Link Range = 60 km
Applying the calculation procedure:
1. Use Table 48 to look up the data throughput capacity rates:
Tx = 41.41 Mbits/s
o
Rx = 41.41 Mbits/s
o
Both = 82.81 Mbits/s
o
2. Divide these rates by 2 to give PTP 600 Lite rates:
Tx = 20.70 Mbits/s
o
Rx = 20.70 Mbits/s
o
Both = 41.40 Mbits/s
o
3. Use Figure 171 to look up the Throughput Factor for 1:1, TDM and Link Range 60 km.
The factor is 0.86.
4. Multiply the rates from Step 2 by the Throughput Factor from Step 3 to give the
throughput capacity of the link:
Tx = 17.80 Mbits/s
o
Rx = 17.80 Mbits/s
o
Both = 35.60 Mbits/s
o
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16 Data Rate Calculations