Title of Dissertation: INVESTIGATION OF PRE-DETECTION SIGNAL PROCESSING OF PSEUDONOISE COMMUNICATION SIGNALS IN THE PRESENCE OF ADDITIVE WHITE GAUSSIAN NOISE AND CW AND BURSTY INTERFERENCE Israel Mayk, Doctor of Engineering Science, 1985 Dissertation directed by: Dr. Solomon Rosenstark Associate Professor Department of Electrical Engineering New Jersey Institute of Technology By comparison to conventional communication systems, spread-spectrum systems are known to be less affected by interference because of their large dimensionality in signal space. Nevertheless, significant performance degradation is experienced when large interference exists in a few or even one signal coordinates. In this case, interference reduction techniques are also known to provide additional processing gain. A novel class of pseudonoise (PN) invariant algorithms is derived to reduce the impact of interference and restore much of the structure of PN signals received in the presence of interference and noise. A PN signal received by a pre-detection signal process (PDSP) implementing a PN invariant algorithm remains unchanged at the output. When an interference waveform is added to the PN signal, most of the DC bias as well as other smooth components of the interference may be significantly reduced at the output of the same PDSP. If n is the longest run in the PN sequence of maximal length N, and R0 is the chip rate, it is shown that the algorithms work well when the interference is sinusoidal with a frequency deviation from the carrier up to R0/N. At such a low frequency deviation, the processing gain is observed to be relatively high and Independent of the phase deviation. As the frequency deviation increases to nR0/N, the performance of the spread-spectrum system decreases to the level that would have been obtained in the absence of the PDSP.

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Investigation of pre-detection signal processing of pseudonoise communication signals in the presence of additive white gaussian noise and CW and bursty interference

Reviews strategies of suppressing interference and noise under various circumstances in order to justify the applications of spread spectrum systems. The basic principles of spread spectrum systems are discussed to demonstrate their capabilities of suppressing noise and interference, and other significant advantages of using such systems. The paper is also examines the factors which affect the capability for interference and noise suppressions and the performance of the systems. It is obvious that the systems can suppress various forms of interference and noise effectively and still achieve other significant goals. The ability of suppressing noise and interference depends on the process gain and correlation properties of the codes of the systems. The overall system performance depends on the degree of synchronization which can be accomplished by the systems.

Interference and noise suppressions using spread spectrum systems

http://ieeexplore.ieee.org/iel7/7567701/7567702/07567711.pdf

C. P. Tou

Papers

Interference and noise suppressions using spread spectrum systems

Interference and Noise Suppressions Using Spread Spectrum Systems