Specifications

• PMP) Same as above, but with one channel being kept at a constant power as a

reference and varying the loss on the second channel.

C. Throughput versus SNR ratio measurements. We will test the sensitivity of the radio system

throughput to added white noise using the RF noise injection system described above. The P2P

and P2MP configurations will be tested with procedures as follows.

• P2P) Set-up a P2P link and inject noise from a broadband noise source. Increase

the noise power while observing throughput and measuring packet loss.

• PMP) Set up a PMP configuration with one BS and two SSs and increase the

noise in one of the BS-SS links, keeping the second BS-SS link constant as a

reference, while observing the throughput and packet losses on both links.

D) Interference Testing. We will test the vulnerability of the system to interference from

adjacent and overlapping RF channels. The 802.16 radio channels, shown in Figure 7, allow for

channel separations that can be less than a channel width apart. Hence adjacent channels can

overlap. We will test using a reference link and a potential interferer using several frequency

configurations. Channel separation must be a least 20 MHz to assure that there is no frequency

overlap.

Figure 7. 802.16 Radio channel assignments

• Set-up a P-P link and a P-MP link on a common set of RF cabling. Three

scenarios of interest are when the radios are operating on 1) the same channel 2)

partially overlapping channels 3) adjacent channels. The performance will be

monitored as the received power from the interfering link is varied.