MEASUREMENTS OF MULTIPATH AND ITS EFFECTS ON TERRESTRIAL VHF RADIO DIRECTION FINDING

PDF

Authors
  1. Read, W.
Corporate Authors
Defence Research Establishment Ottawa, Ottawa ONT (CAN)
Abstract
The report details the investigation of VHF radio direction finding (DF) and the effects of multipath propagation for terrestrial paths. For this investigation, an eight-channel DF system was used to make field measurements of a transmitter as it was slowly moved along a designated route. This allowed the fine scale effects of multipath on the measured signal bearing and power to be observed - effects which had been previously observed as being noise-like in nature. Computer modelling was also used in order to develop simulations able to reproduce the effects observed in the field measurements. This has lead to the identification of the main sources of multipath, and a statistical assessment of their numbers and distribution. The computer models also allowed other factors affecting DF accuracy to be investigated which include: the transmitter-receiver path length, the size of the clearing at the DF site, the DF antenna height, and the DF algorithm. The main conclusions are that multipath is a major impediment to very high accuracy DF for terrestrial VHF DF systems, but that steps can be taken to mitigate its effects.
Keywords
MUSIC;Multipath model;N-Channel;Maximum Likelihood Methods
Report Number
DREO-1325 — Technical report
Date of publication
01 Dec 1997
Number of Pages
90
DSTKIM No
98-00453
CANDIS No
507092
Format(s):
Hardcopy;Document Image stored on Optical Disk

Permanent link

Document 1 of 1

Date modified: