Accession Number : AD0803215

Title :   INTERFERENCE REDUCTION TECHNIQUES FOR PULSED TRANSMITTERS.

Descriptive Note : Quarterly rept. no. 3, 29 Mar-5 Aug 66,

Corporate Author : ENERGY SYSTEMS INC PALO ALTO CA

Personal Author(s) : Goldfarb, Eli M. ; Cumming, Raymond C.

Report Date : AUG 1966

Pagination or Media Count : 72

Abstract : The purpose of this project is to investigate the interference producing characteristics of pulsed transmitters and then to seek to minimize this generation of spurious emission exclusive of filtering and shielding. Studies of the EMC of radar performance and the comparison of the merits of several representative signals are extended with respect to (a) EMC, range resolution and range ambiguity on the basis of equal detection probability and range accuracy and (b) EMC, velocity resolution and velocity ambiguity on the basis of equal detection probability and velocity accuracy. The general equations for trapezoidal pulse and spectrum shapes are tabulated together with several examples for particular shapes. Amplitude-modulation/phase-modulation curves are complex for typical klystrons, traveling-wave tubes and for a crossed-field amplifier, as functions of input signal level. The use of the gain saturation curves was demonstrated to relate the data to the output voltage level. The resulting curves were compared to several phase-envelope functions previously analyzed. Flat-top pulses with error-function rising and falling portions were evaluated. The spectrum for this pulse shape was compared to the spectra for other flat-top pulses previously considered. The spectrum for the error-function flat-top pulse is closest to the ideal pulse spectrum (gaussian) with little sacrifice in efficiency from that of the rectangular pulse. A nearly gaussian periodic pulse train was studied. The spectrum is bounded and the time-domain signal consists of periodic repeating pulses whose intrapulse amplitude is very low. Also included is a copy of a paper presented at the Ninth Modulator Symposium at Fort Monmouth in May 1966. (Author)

Descriptors :   *RADAR TRANSMITTERS), (*ELECTROMAGNETIC COMPATIBILITY, (*RADIOFREQUENCY INTERFERENCE, REDUCTION), MODULATORS, AMPLITUDE MODULATION, PHASE MODULATION, KLYSTRONS, TRAVELING WAVE TUBES, CROSSED FIELD DEVICES, RADAR PULSES, GRAPHICS.

Subject Categories : Active & Passive Radar Detection & Equipment
      Electromagnetic Pulses

Distribution Statement : APPROVED FOR PUBLIC RELEASE