Experimental Optimization and Evaluation of Telemetry Systems

A careful laboratory program to experimentally optimize and evaluate four telemetry systems in wide use (FM-FM, PAM-FM, PDM-FM and PCM-FM) has been concluded as part of a general study of problems in the telemetry field. Each of the four systems was implemented in the laboratory and the system under test was modulated by random signal sources typifying actual data. Broad-band random noise was then introduced at the RF and the various system parameters were optimnized to obtain the lowest threshold for stated performance. Having optimized the parameters in this manner, performance against other types of interference was also measured. For each system an accurate error comparator was designed which repetitively sampled the system input and output and compared the samples for error. The information obtained on internal parameter optimization and over-all performance for each system is extremely useful to systems design as well as to evaluation and comparison of the systems.