Accession Number : AD0809822

Title :   MINIMUM ERROR RATE DIVERSITY COMBINING.

Descriptive Note : Final rept. Oct 65-Sep 66,

Corporate Author : GENERAL DYNAMICS/ELECTRONICS ROCHESTER NY

Personal Author(s) : Horvat, V. ; Hatley, D.

Report Date : FEB 1967

Pagination or Media Count : 110

Abstract : This report presents the results of a study which was undertaken to explore the feasibility of reducing error rate in hf binary data transmission by means of multible branch receiving diversity. The work consisted of three tasks, viz: an examination of the theory of hf wave propagation; design, and modeling of simple vertically polarized antennas, and of orthogonally polarized multiple diversity receiving arrays for hf; and the design of a six-branch diversity combiner with provisions for dealing with certain reception anomalies common to hf. It is concluded that both space and polarization diversity methods are effective in hf reception. Angle diversity, while probably effective, is not particularly attractive because of the complex structure needed to obtain the requisite beam-widths and firing angles. Methods for obtaining six-branch receiving diversity are presented. A cost comparison of six branch diversity reception with ADAPTICOM showed a possible advantage for the latter system, although the results were not considered conclusive because of a lack of performance data. Comparative testing on transcontinental hf links is recommended. (Author)

Descriptors :   *ANTENNAS), (*DIVERSITY RECEPTION, DATA TRANSMISSION SYSTEMS, HIGH FREQUENCY, ANTENNA ARRAYS, POLARIZATION, ANTENNAS, IONOSPHERIC PROPAGATION, ATTENUATION, ANTENNA RADIATION PATTERNS, MATHEMATICAL MODELS, ERRORS, COSTS.

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE