1. Sponsored by the National Science Foundation WiMAX Campus deployment Status & measurements Thanasis Korakis Polytechnic Institute of NYU July 27, 2011

2. Sponsored by the National Science Foundation2 Base Station Configuration The BS (server, IDU) have been installed in the network room of the Library in the ECE Dept Building (5 Metrotech Center). The BS server uses the WiMAX RF Agg Mgr to control access and set BTS parameters. The software is updated regularly to the latest release. The outdoor parts (sector antenna, GPS antenna, ODU) have been installed on the roof of the ECE Dept Building (5 floor building). The network is up and running on a regular basis since September 2010. WiMAX experiments are conducted using different devices such as Beceem USB Dongle with Windows and Dell Linux netbooks with internal Intel WiMAX card. WiMAX-equipped clients are integrated in OMF testbed so that researchers can run WiMAX experiments via OMF.

3. Sponsored by the National Science Foundation3 Range and Throughput Experiment Configuration To gather throughput statistics, we used Bittorrent rather than traditional network testing tools (e.g. iperf) –Behavior of a TCP flow, as measured by iperf, gives pessimistic picture of network performance: link under-utilization, poor recovery from loss, highly variable results between iperf trials, and overall degraded end-to-end performance. Each measurement point takes some time to collect, so this tool is not suitable for taking hundreds of measurement points over a wide area. –Bittorrent uses multiple parallel connections to maximize link utilization, and DL and UL speeds stabilize quickly as link quality changes while we move throughout the coverage area. BS tx power = 38 dBm

4. Sponsored by the National Science Foundation4 Main Execution Loop of Measurement Script Python script to aid in efficiently collecting range and throughput measurement points over a wide area. The script will be ported to C so as to make use of OML libraries.

5. Sponsored by the National Science Foundation5 Results Maximum throughput: 1Mbps UL, 17Mbps DL Throughput grows linearly with RSSI, CINR; more loosely correlated with distance from BS due to the presence of buildings and other obstructions. Cell radius: ~0.5 km Performance deteriorated at long distances and without clear sight to the BS. Further measurements are being taken to observe the behavior of different transport layer protocols and the effect of ARQ on network performance.