DocumentCode :
1144610
Title :
Interference Effects of Pseudo-Random Frequency-Hopping Signals
Author :
Cohen, Stanley A.
Author_Institution :
IIT Research Institute, Electromagnetic Compatibility Analysis Center, Annapolis, Md. 21402
Issue :
2
fYear :
1971
fDate :
3/1/1971 12:00:00 AM
Firstpage :
279
Lastpage :
287
Abstract :
When a pseudo-random frequency-hopping signal is intercepted by a conventional receiver operating within the same frequency band, the interfering signal has the form of a pulse-amplitude modulated signal. Each pulse amplitude is dependent upon the hopping frequency and the selectivity characteristic of the victim receiver. The probability density function for the interfering pulse amplitude prior to demodulation is determined when the probability density function for the hopping frequency is uniform and the victim-receiver characteristic is 1) ideal flat bandpass, 2) single tuned, and 3) Gaussian shaped. It is shown that the average interfering pulse amplitude and interference power decrease as the frequency-hopping bandwidth increases with respect to the victim-receiver bandwidth. Fast Fourier transform computer techniques are used to obtain the probability density function of the interference amplitude in a Gaussian receiver when several (from 2 to 10) pseudo-random frequency-hopping systems are simultaneously using the same frequency band. The probability that the interference exceeds a prescribed threshold value is computed from the derived probability density functions. This probability may be used in signal-to-interference ratio calculations, to describe the capture effect, or to compute the expected number of clicks produced in an FM discriminator.
Keywords :
Bandwidth; Electromagnetic analysis; Electromagnetic compatibility; Frequency modulation; Interference; Jamming; Probability density function; Probability distribution; Pulse modulation; Spread spectrum communication;
fLanguage :
English
Journal_Title :
Aerospace and Electronic Systems, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9251
Type :
jour
DOI :
10.1109/TAES.1971.310367
Filename :
4103697
Link To Document :
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