Cambium Networks PMP 450 AP, Планирование и руководство по установке

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Chapter 3: System planning Radio Frequency planning
Page
3-25
In the example in below figure the second equation is not satisfied, and the two systems cannot be co-
located. The plot to the right also shows that with this frame configuration the LTE AP is still
transmitting when the PMP AP is already receiving. This creates interference at the PMP AP receiver.
Using the tool, parameters can be updated in order to find a set of values that allows for co-location.
For example, changing the duty cycle of the PMP AP from 70% to 80% makes both equations true, and
there is no longer overlap between one AP transmitting and the other receiving.
Multiple OFDM Access Point Clusters
When deploying multiple AP clusters in a dense area, consider aligning the clusters as shown below.
However, this is only a recommendation. An installation may dictate a different pattern of channel
assignments.
Mode PMP Frame Configuration 2
Channel Bandwidth (MHz) 20 S frame configuration 7
Max Range (mi) 5 DL Cyclic Prefix Normal
One way air delay (ns) 10000 UL Cyclic Prefix Normal
Calculated PTP range (mi) 1.861
Dowlink Data 70%
Contention slots
3
Frame Period (ms)
5
DL end 3.271 DL end 3.715
UL start 3.457 UL start 3.857
PMP DL end 3.271 < LTE UL start 3.857 OK
LTE DL end 3.715 < PMP UL start 3.457 OK
PMP Configuration LTE Configuration
PMP - LTE co-location tool
PMP Timing (ms) LTE Timing (ms)
CHECKS
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
PMP
LTE
Frames
Downlink Gap Uplink
Mode PMP Frame Configuration 2
Channel Bandwidth (MHz) 20 S frame configuration 7
Max Range (mi)
5
DL Cyclic Prefix
Normal
One way air delay (ns) 10000 UL Cyclic Prefix Normal
Calculated PTP range (mi)
1.861
Dowlink Data 80%
Contention slots
3
Frame Period (ms)
5
DL end 3.708 DL end 3.715
UL start 3.894 UL start 3.857
PMP DL end 3.708 < LTE UL start 3.857 OK
LTE DL end 3.715 < PMP UL start 3.894 OK
PMP Configuration LTE Configuration
PMP - LTE co-location tool
PMP Timing (ms) LTE Timing (ms)
CHECKS
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
PMP
LTE
Frames
Downlink Gap Uplink