Accession Number : AD0460593


Title :   THE SYNTHESIS OF SWEEP-FREQUENCY GROUND BACKSCATTER BY DIGITAL COMPUTER


Descriptive Note : Technical rept.


Corporate Author : STANFORD UNIV CA STANFORD ELECTRONICS LABS


Personal Author(s) : Croft, T A


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/460593.pdf


Report Date : 01 Mar 1962


Pagination or Media Count : 163


Abstract : A high-frequency pulse radar often receives energy which has propagated through the ionosphere to the ground, scattered, and then returned to the radar again via the ionosphere. When this energy is displayed as a function of both time delay and operating frequency, the record is called sweep-frequency backscatter. In this report a digital computer technique is devised to synthesize such records in a manner which is quantitative in all parameters. The synthesis is designed so that very few approximations are needed. Full allowance is made for the following: a spherical earth and ionosphere; a wide variety of electron-density variations in height and range; ionospheric absorption which varies with frequency, range, and the ray angle; radar antenna gain as a function of frequency, azimuth, and elevation; ground-scattering characteristics which vary with frequency, range, and the angle of incidence; ground-reflection coefficients which vary with frequency and range; the transmitted pulse shape, duration, and power level; receiver bandwidth and total received noise power. There are two major uses for the digital synthesis.


Descriptors :   *RADAR PULSES , COMPUTER PROGRAMMING , DIGITAL COMPUTERS , DISPLAY SYSTEMS , ELECTRON DENSITY , GAIN , GEOPHYSICS , IONOSPHERIC PROPAGATION , MATHEMATICAL ANALYSIS , MATHEMATICAL MODELS , MULTIPATH TRANSMISSION , RADAR ANTENNAS , SCATTERING


Subject Categories : Active & Passive Radar Detection & Equipment


Distribution Statement : APPROVED FOR PUBLIC RELEASE