Specifications

An important part of the test bed is the web interface for the AN-50. The system status
screen is shown below in Figure 3.7. This screen shows the current received power (RSSI),
signal to noise and distortion ratio (SINADR), as well as statistics on packet retransmissions on
the wireless link. Redline has released RF Monitor, a tool that automatically polls this web
interface and plots the results. This software gives much more consistent results then what was
achievable by manually observing the web interface, which updated more slowly. The RF
Monitor software was installed on the PCs. A typical graph produced by RF Monitor is shown in
Figure 3.8
For collecting end-to-end performance data “IP Traffic Test and Measure” will be used to record
the data regarding throughput and delay. This software will also run the packet generation so
that the data flow can be shaped to emulate data from acoustical sensors, the primary data source
that AAC plans to use. The Parameters tab is shown in Fig. 3.4. This tab adjusts the number of
packets, packet size and packet rate. The payload of the packet can be set by several parameters
as well. Random data is used to emulate traffic from a sensor.
Iperf, an open source command line network analysis tool has been installed on several
computers and will be used to validate the results of the IP Traffic testing. Iperf runs for a set
amount of time and has the ability to generate packets of various sizes under both UDP and TCP
protocol. The results from Iperf are given as average throughput over a given time interval, one
second was used in this case. The total average throughput for the duration of the test is also
reported as well as jitter and packet loss statistics. Readout of typical Iperf results is shown
below in Figuer 3.9. Iperf is freely available. This software was able to produce much higher
throughputs then what IP Traffic did. The results obtained with Iperf are more inline with the
manufacturers specifications for the radio system.
An actual deployment test bed is also necessary to support the lab findings and provide a final
proof of performance. This test can be done using the existing Redline equipment. This test is a
simple throughput test under a deployment scenario of 20 miles range using two of the 12° sector
antennas. The antenna alignment is done by listening to the audible sweep that is transmitted
from the transceiver unit while adjusting the antenna aiming. The higher the frequency of the
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