1. S-Band and L-Band Transmission Function
This function modulates and transmits reference data. Data is transferred
at rates between 1.023 and 5.115 Mbps into either an S-band transmission
string with a carrier frequency of 2491.005 MHz or an L-band transmission
string with a carrier frequency of 1595.88 MHz. The data is modulated
using Binary Phase Shift Keying (BPSK) modulation, amplified for transmission
and filtered before final output.
2. S-Band Receive Functions
The S-band receiver receives a variety of signals within a frequency range
from 2655 to 2660 Mhz. An S-band reference signal with a carrier frequency
of 2656.39 MHz is received, downconverted and upconverted to the S-band
(2491.005 MHz) and L-band (1595.88 MHz) frequencies defined above. This
signal may be transmitted simultaneous with the other S-band and L-band signals.
A second S-band continuous wave frequency of 2659.8 MHz is received and detected to recover a 10.23 MHz frequency tone.
3. Connectivity and Redundancy
Several key elements of the subsystem are redundant and cross-strapped to
achieve Hi system reliability. This is implemented using standard switches,
RF couplers, RF dividers, and RF combiners.
4. Key Performance Requirements
L-Band Transmitter:
Power: 18 Watts minimum
Bandwidth: 15 MHz
Group Delay: +/- 3 nsec over 10.23 MHz
S-Band Transmitter:
Power: 18 Watts minimum
Bandwidth: 15 MHz
Group Delay: +/- 3 nsec over 10.23 MHz
Input Power: -96 dBm
Bandwidth: 5 MHz
Noise Figure: 2.4 dB maximum
Phase Noise: 1 degree rms maximum
5. Products
L-3 Com supplies the system engineering, component designs and the
Manufacturing and qualification for the components which make up the
RF Sub System for ETS-8.
Frequency Synthesizer - 11 outputs
L and S band BPSK modulators
L and S band Power Amps
S band Receiver PLX
Hybrid switches and combiners
100 Vdc power supplies
The RF Subsystem is supplied to Toshiba of Japan for the ETS-8 satellite program.
Points of Contact:
Paul Mellon, Program Manager, Space Communications
Bob Lisowski, Director, RF Systems
