AN/FPS-95 Research and Development Program (Final Technical Report, Naval Research Laboratory, Long-Path One-Way Propagation Effects)
Abstract
Reciprocal tests were run between the U.K. and a station on Cyprus to measure (1) the dynamic range constraints imposed by a one-way ionospheric path between two points in over-the-horizon HF propagation, and (2) possible AN/FPS- 95 antenna and/or ground screen noise sources in transmission or reception which are not excitable by line-of-sight measurements. Results indicate that the ionosphere presents no source of noise as a transmission medium for low elevation angles (3 to 5 elevation), within the capabilities of the transmitting and receiving equipment used. The noise limitations measured in the AN/FPS-95 receive tests were -77 dB and -85 dB, mean noise levels in a two-Hertz bandwidth centered at 5 and 18 Hertz, respectively, from the spectrum peak. These levels are thought to be skirts of the transmitted spectrum, although line-of-sight monitoring by the test van could not conclusively verify this because of local aircraft contamination of signal. On the reciprocal path test, in which a receiver/processor test van measured the AN/FPS-95 transmission, the received signal was clean 80 to 83 dB from spectrum peak across 4 to 12 Hertz from the spectrum peak.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1974
- Accession Number
- ADC003502
Entities
People
- Dennis B. Trizna
Organizations
- United States Naval Research Laboratory