Accession Number : AD0831737

Title :   FREQUENCY SPECTRAL DETERMINATION OF THE ISOLATION BETWEEN RADAR TRACKING DATA AND SHIP'S MOTION FOR APOLLO CLASS SHIPS,

Corporate Author : PAN AMERICAN WORLD AIRWAYS INC PATRICK AFB FL AEROSPACE SERVICES DIV

Personal Author(s) : Tokareff, P., Jr. ; Pinion, J. F.

Report Date : MAY 1968

Pagination or Media Count : 44

Abstract : The installation of precision tracking radars aboard the Apollo ships has resulted in new and unique problems which are not encountered by land based equipments. Among the problems encountered are the contamination of data due to uncorrected ship's motion and the quantitative measurement of this degradation. The degree to which the degrading effects are corrected is expressed as the isolation between ship motion and radar tracking data. Results are presented from an at-sea test performed on the T-AGM-19 (USNS Vanguard) Apollo ship. Both power spectra and cross-spectra are used for determination of isolation. Results from the test are for the elevation versus ship's motion case. For the S-band, an isolation of 41.3 decibels was obtained; this included the effect of on-mount gyros and the inherent tracking capability of the radar. The C-band results did not include either the on-mount gyros or the feedforward stabilization. The isolation obtained for the C-band radar was 34 decibels, considering only the inherent tracking capability, while 50 decibels was obtained considering both the inherent tracking capability and the correction for antenna lag errors in post-test data reduction. (Author)

Descriptors :   (*RADAR TRACKING, SHIPBOARD), NAVAL VESSELS, MANNED SPACECRAFT, LUNAR CRAFT, RADAR ANTENNAS, STABILIZATION, ERRORS, POWER SPECTRA, S BAND, C BAND, GYROSCOPES, CORRECTIONS, CORRELATION TECHNIQUES, MOTION, ACCURACY.

Subject Categories : Active & Passive Radar Detection & Equipment
      Spacecraft Trajectories and Reentry

Distribution Statement : APPROVED FOR PUBLIC RELEASE