PMP49400 Performance - Throughput

I recently received some PMP49400 equipment and have been evaluating it for a city-wide deployment. When I tested the equipment in my lab (1 AP and 1 SM) I noticed that the bandwidth is not synchronous, the downlink speed is roughly 17Mbps and the uplink speed is only 3Mpbs. The specifications indicate 21Mpbs of aggregate throughput, but there isn’t a great deal of information available on how that number is computed. Is this typical performance for this product?

I’ve got the equipment installed in the field now and the performance is less then expected. I have clear line of site, 3.61 miles between AP and SM, -79dB receive power level, rate is 3x/2x, and the best I can get out of it is 9.02Mbps downlink and 1.21Mbps uplink (Aggregate 10.23Mbps). The efficiency is only 76/69. Is it possible I have something mis-configured that is limiting my throughput or are these pretty realistic numbers?

Thanks for your help

Problem Solved:
After tinkering around I found that the “Downlink Data” field doesn’t just control the downlink data rate but also the uplink data rate. IMHO - this should be called something else like Throughput Ratio.