About Hbs Overhead; Figure 10-23 Example 3: Half - Radwin 5000 HPMP User Manual

About HBS Overhead
About HBS Overhead
There is always some overhead on the HBS. Recall that one time slot in each of the uplink and
downlink directions is reserved by the HBS for sector management.
In our four examples we noted that the occurrence of HBS overhead increases when
allocating time slots even to "idle" HSUs.
As we saw, the percentage point sector load increases as you allocate further downlink time
slots, or maintain any unused but allocated uplink time slots.
It is straightforward to demonstrate that overhead is also channel‐bandwidth dependent. If
you repeat the four examples under 10 and 5 MHz channel bandwidth, the load overhead
percentage increases as channel bandwidth decreases. Conversely, if you are able to operate
at 40MHz, the overhead percentage drops.
To illustrate the effect of different channel bandwidths, we show in order, Example 3 at 10, 20
and 40 MHz:
Figure 10‐23: Example 3: Half the uplink time slots reserved at 10 MHz CBW
Notice that at 10MHz channel bandwidth, the sector utilization is 100% in both directions!
RADWIN 5000 HPMP User Manual Release 3.5.70 10‐20