Accession Number : AD0707793

Title :   A THEORETICAL AND EXPERIMENTAL STUDY OF RADAR MULTIPATH EFFECTS OVER THE SEA.

Descriptive Note : Technical rept.,

Corporate Author : JOHNS HOPKINS UNIV SILVER SPRING MD APPLIED PHYSICS LAB

Personal Author(s) : Pidgeon,Vernon W.

Report Date : OCT 1969

Pagination or Media Count : 43

Abstract : Whenever a radar signal is used against a low-altitude target, signal strength may fade because signal reflections from the surface of the earth interfere with the direct signal from the target. This fading can cause serious missile-guidance problems. A digital computer program has been developed that computes the effects of radar multipaths over the sea, and an experimental program has been conducted in which multipath effects at L- and S-bands have been measured. With certain notable exceptions, the results of the theoretical and experimental programs agree very closely. Modifications to the computer program that are suggested by the experimental results are primarily to the computations in the vicinity of the radar horizon, where signal strength should be computed by using a fall-off rate (in signal strength per given range) that is proportional to the cube root of the radar frequency. Values of the rough-sea reflection coefficient have been verified for grazing angles down to less than one milliradian. (Author)

Descriptors :   (*OCEAN WAVES, *RADAR INTERFERENCE), (*RADAR SIGNALS, MULTIPATH TRANSMISSION), COMPUTER PROGRAMS, MULTIPATH RADAR, L BAND, S BAND

Subject Categories : Active & Passive Radar Detection & Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE