STUDY OF TELEMETRY RECEIVER AND RECORDER PHASE LINEARITY PROBLEMS
Abstract
The problem of phase nonlinearities in telemetry-receiving systems is studied. The principal data-degrading effect is shown to be intermodulation distortion of FDM telemetry signals. Another form of data degradation, namely intersymbol interference in TDM telemetry signals, is found not to be related directly to phase non-linearities, but rather to the transient response of the receiving system. The noise-loading technique is introduced as an effective means of characterizing, analyzing and measuring intermodulation distortion. Analytical results are established relating the amount of intermodulation distortion to signal and receiving-system parameters. These relationships are verified experimentally using typical telemetry receivers, converters and recorders. Some other sources of data degradation are also identified and evaluated. The study results are used to establish quantitative tradeoffs between the performance parameters of receiving systems. These tradeoffs are then used in formating methods of specification for low data degradation. Improvements that can be implemented in existing and future systems are discussed, and it is recommended that study and development efforts should be undertaken to improve data quality.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1966
- Accession Number
- AD0638685
Entities
People
- Ahmad F. Ghais
- Charles J. Boardman
- Eugene J. Ferrari