AvL Proprietary and Confidential
Content is Subject to Change without Notice
Page
161
of
195
7.4.7 Signal Source = RSL
A Received Signal Level (RSL) broadband power detector comes standard on all AAQ equipped AvL
antennas. It is designed to detect power in the standard L-band used by most satellite terminals,
specifically 950 – 2150 MHz. AvL antennas are typically wired to provide the RSL with a sample of
the satellite signal available on the cable running from the customer provided LNB to the modem via
an AvL provided in-line signal splitter or coupling device. Based on the nature of its design, the RSL
is a great detector of satellite signals, but it cannot reliably confirm that the detected signal is
originating from the target satellite. For this reason, extra steps are sometimes required to increase
the probability that the antenna acquires and peaks on the correct satellite.
As mentioned previously in this chapter, prior to acquisition of a satellite the AAQ is typically
operating with a very good knowledge of the EL angle and a relatively poor estimate of the AZ angle
for the antenna beam. Consequently, the AAQ searches for the target satellite using relatively wide
AZ line scans as illustrated in Figure 7.4.7a. While performing an AZ line scan, the AAQ records RSL
output. Upon completion of each scan, the AAQ reviews data taken on that pass and compares it
against a user defined threshold value. If the threshold value is met or exceeded, then the AAQ will
return the antenna to the location corresponding to the highest level detected and begin peaking on
the signal. Otherwise, the AAQ will continue with its raster scan routine. A successful acquisition of
Satellite A after a single AZ line scan is illustrated in Figure 7.4.7b.
