A2537-002/01 February 2020 6-31 SEMCO Proprietary Information
Figure 6-44 (continued)
SOQPSK-LDPC Settings on Remote GUI
6.8.9 Space Time Coding (STC)
As previously discussed in paragraph 6.2.8, this code uses space diversity and time diversity to overcome
the two-antenna problem, which is characterized by large variances in the antenna gain pattern from a test
article caused by transmitting the same telemetry signal time through two transmit antennas. These signals
are typically delayed in time and have differing amplitudes.
Space-Time-Coding (STC) only applies to SOQPSK-TG modulation. The input bit stream is space-time
coded, resulting in two parallel bit streams that then have a pilot sequence added to each bit stream at
fixed bit intervals (or blocks). These encoded/pilot-added streams are then individually modulated through
phase-locked transmitters to a carrier using SOQPSK-TG modulation, power amplified and then connected
to a top and bottom antenna.
Space-time decoding of this signal in the SOQPSK-STC mode encompasses, among other parameters,
estimating frequency offset, delays, gains, and phase shifts in the SOQPSG-STC signal.
Specific instructions for setting up, controlling and displaying applicable information on both the Front Panel
LCD/Keypad and remote GUI is scheduled to be incorporated in the next revision to this manual.
LDPC Derandomizer Selection
To Next Page
Loading...