Laboratory Subsystem Performance Evaluation 1.
Abstract
Measurements were made to evaluate the performance of a laboratory version of a 1-GBPS laser communication system. The system consisted of a single-frequency argon laser operating at 5145 A wavelength, a broadband (1 to 2 GHz) electro-optical modulator, a broadband photomultiplier, and electronic modulation, demodulation, bit, synchronization, and error detection equipment. The basic measurements made were of bit error rate (BER) as a function of photocurrent of the receiving photodetector. Measurements of the electronic subsystems alone were made of BER as a function of signal-to-noise ratio (SNR), using added gaussian noise. Performance of the QPSK modem/bit synchronizer was measured to be within 3.9 dB of theoretical nonbandlimited integrate-and-dump performance at BER = 0.000001. Performance of the complete system was measured to be within 6.7 dB of theoretical at BER = 0.000001 for 50-percent depth of modulation of the optical carrier, using two asynchronous 500-MBPS data streams. Other tests were made to determine the effects of optical background, frequency-multiplexed telemetry, and AGC operations using gain control of the phototube. Tests were also made to determine the sensitivity of performance to phase and other errors in the electronic circuitry.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1973
- Accession Number
- AD0907027
Entities
People
- D. G. Peterson
- R. B. Ward
Organizations
- Lockheed Martin Missiles and Space