Oct 2, 2008

Goals

• RSSI measurements using the NexSTAR for ground based MNRs to generate RSSI field estiamtes

Flight Review

The goal of today's flight was to provide the first RSSI (received signal strength) measurements of the NexSTAR with ground based MNRs (meshed network radios). An interesting result of the flight was that in addition to measuring the SNR of our MNR nodes, we also measured the SNR of several other 802.11b nodes that were nearby the Table Mountain area. In effect, this shows that the UA is able to measure the SNR of nodes that it did not necessarily try to establish communication with, i.e. it can eaves-drop on other nodes at the MAC layer. The other major result was that it appears that for Cory's research, better SNR variability is obtained when the UA does a square pattern over a circular pattern. This is due to the antenna patterns of the nodes and the relative orientation of them. When the UA is in a constant bank, then the antenna on the UA and on a ground node are never aligned.

All of the available plots can be found in the plots subfolder.

NexSTAR-1 Flight 1

Flight Time: 27:14
Distance covered: ~18 miles


We took off from the gravel pit site and after verification of autopilot flight, sent the plane to the experimental pattern to observe RSSI (Check out the video capture of how the observer saw the takeoff on full zoom through the video camera). While conducting the experiment, a localized thunderstorm rapidly developed and we ended up flying through rain for the latter part of the experiment (see the second video capture of the NexStar flying towards storm clouds).

We gathered RSSI measurements while the NexStar flew a Zamboni and circular pattern over the MNR located on the ridge. Another MNR was located nearby the GCS-Laptop. This flight also used the higher capacity battery pack which gave us a much longer flight time.

YouTube Video

Flight Overview

Circluar Orbit

Zambonie Pattern