Browsing International Telemetering Conference Proceedings, Volume 29 (1993) by Authors
A Comparison of Various Video Compression Methods for Use in Instrumentation SystemsRieger, James L.; Gattis, Sherri L.; Naval Air Warfare Center, Weapons Division (International Foundation for Telemetering, 1993-10)Various forms of 'lossy' and 'lossless' encoding have been implemented or proposed to allow compression of still and motion picture images, with varying degrees of success which in turn depend on how success is defined. Proponents of various systems claim 'compression ratios' which by their nature defy comparison of one system with another and suggest there actually may be something like a free lunch. This paper compares various compression methods as well as the implications involved in using them and what happens when different systems encounter the problems associated with the uses of the restored picture.
A Miniature Blast-Gauge Charge Amplifier SystemRieger, James L.; Weinhardt, Robert; Naval Air Warfare Center, Weapons Division (International Foundation for Telemetering, 1993-10)Transducers whose outputs are characterized as a charge require signal conditioning to convert the charge produced to a voltage or current for use in instrumentation systems. Blast gauges, in particular, require processing which preserves the transient nature of the data and very fast risetimes, which would otherwise be degraded by long cable runs and parasitic capacitances. A charge amplifier which amplifies and converts a charge to a low-impedance voltage suitable for driving coaxial lines is described, along with theory of operation. Charge amplifiers of the type described are relatively unaffected by temperature and power supply variations, and occupy less than two square inches of printed circuit board space per channel.
Use of Nonstandard FM Subcarriers for Telemetry SystemsRieger, James L.; Naval Air Warfare Center, Weapons Division (International Foundation for Telemetering, 1993-10)Subcarrier use in telemetry has decreased in recent years due to emphasis on all-digital systems, but some cases lend themselves more easily to a mixed-service system carrying subcarriers along with a baseband signal. The 'IRIG 106' Telemetry Standards have maintained and expanded several series of FM subcarriers, but some uses are better served with 'non-standard' subcarriers that might be standard in other types of service, making components relatively easily available and inexpensive. This paper examines topics from the RCC study and describes some of the uses of subcarrier systems available to the telemetry designer.