Showing papers on "Spread spectrum published in 1972"

A surface wave spread spectrum communication link.

Abstract: This development has resulted in a fast lock-up, 8-MHz bandwidth, 8-KHz data rate, spread spectrum communication link breadboard that is implemented using surface wave devices as the primary signal generators and signal processing elements. It uses surface wave tapped delay lines (SWTDL's) in the transmitter to generate the signals and in the receiver to match filter detect them. The system also incorporates a re-entry delay line (circulating integrator) which increases the effective code length per data bit by eight-fold.

Performance of Hard-Limited Spread-Spectrum Transmission Systems

Abstract: : The detection of spread-spectrum multiple-access signals relayed through a hard-limiting repeater is of considerable practical interest in satellite communication. The study provides a method for analyzing accurately the detection of a hard-limited PSK signal buried in noise having non-Gaussian components, by using a correlation detector. The problem is of both theoretical and practical interest. The probability of error is shown to be directly calculable from the characteristic function of the receiver output, without the need of obtaining the probability density function, which generally requires a difficult inverse transformation of the characteristic function. This approach might be of some theoretical interest in solving related problems.