Accession Number:

AD0836764

Title:

PSEUDORANDOM FREQUENCY MODULATION IN RANGE-DOPPLER RADAR.

Descriptive Note:

Scientific rept. no. 29,

Corporate Author:

STANFORD UNIV CA STANFORD ELECTRONICS LABS

Personal Author(s):

Report Date:

1968-05-01

Pagination or Media Count:

80.0

Abstract:

This study describes a class of waveforms suitable for simultaneous measurement of range and doppler shift. These waveforms are characterized by a uniform distribution in frequency and by a random rate of frequency change. Uniform frequency distribution is attained by a uniform spacing of frequencies with each frequency present for an identical length of time. A random rate of frequency change is attained by sequencing the frequencies by a pseudorandom number generator. Ambiguity functions are computed for pseudorandom frequency-modulated waveforms designed for ionospheric backscatter studies. By suitable choice of parameters, the ambiguity function consists of a narrow central peak surrounded by a plateau which is randomly fluctuating between zero and approximately twice its average. The pseudorandom frequency-modulated waveforms are generated by a frequency synthesizer controlled by a linear shift register. Identical waveforms are assured by a suitable frequency programming which returns the synthesizer to the same state at the beginning of each transmission. Author

Subject Categories:

  • Numerical Mathematics
  • Active and Passive Radar Detection and Equipment

Distribution Statement:

APPROVED FOR PUBLIC RELEASE