Accession Number : ADP006894

Title :   Doppler-Multipath Tolerant Voice Communications,

Corporate Author : ROYAL AEROSPACE ESTABLISHMENT FARNBOROUGH (UNITED KINGDOM)

Personal Author(s) : Harris, R. M.

Report Date : JUN 1991

Pagination or Media Count : 11

Abstract : Line-of-sight communication between high-performance aircraft has been found to be subject to a peculiar form of multipath radio-wave propagation - Doppler multipath. It degrades analogue voice reception on the standard-fit UHF radio, producing low-frequency random noise and warbling. Various modifications were carried out on the aircraft's communications system but the problem remained; all the evidence points to a natural phenomenon. The reported observations are corroborated by theoretical studies and laboratory simulations of multipath radio-wave propagation between 2 points moving relative to a diffusely scattering reflector.

Descriptors :   *RADIO WAVES, *COMMUNICATION AND RADIO SYSTEMS, *MULTIPATH TRANSMISSION, *ATTACK AIRCRAFT, *AIR TO AIR, AIRCRAFT, LABORATORIES, LINE OF SIGHT, NOISE, PROPAGATION, RADIO WAVES, RECEPTION, REFLECTORS, SCATTERING, SIMULATION, STANDARDS, VISION, WAVE PROPAGATION, ELECTROMAGNETIC WAVE PROPAGATION, ULTRAHIGH FREQUENCY, NOISE(ELECTRICAL AND ELECTROMAGNETIC), RADIOFREQUENCY, AERIAL WARFARE, REPRINTS, SYMPOSIA.

Subject Categories : Radio Communications
      Radiofrequency Wave Propagation
      Attack and Fighter Aircraft

Distribution Statement : APPROVED FOR PUBLIC RELEASE