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
Descriptors:
- *FREQUENCY MODULATION
- *DOPPLER RADAR
- MONOSTATIC RADAR
- DOPPLER EFFECT
- RADAR TRACKING
- DISTRIBUTION
- BACKSCATTERING
- WAVEFORM GENERATORS
- DATA PROCESSING
- DIGITAL COMPUTERS
- SIGNAL TO NOISE RATIO
- RADIO ASTRONOMY
- RADAR RECEIVERS
- WAVE FUNCTIONS
- INTEGRAL TRANSFORMS
- SHIFT REGISTERS
- FREQUENCY SYNTHESIZERS
- SEQUENCES(MATHEMATICS)
Subject Categories:
- Numerical Mathematics
- Active and Passive Radar Detection and Equipment