Accession Number : ADP006882

Title :   Eigenvector Weighting as an Adaptive Array Interference Cancellation Technique,

Corporate Author : COMMUNICATIONS RESEARCH CENTRE OTTAWA (ONTARIO)

Personal Author(s) : Jenkins, R. W. ; Moreland, K. W.

Report Date : JUN 1991

Pagination or Media Count : 13

Abstract : Adaptive antenna techniques normally make use of known properties of the desired signal, such as its direction or an embedded code, to distinguish it from interference. When this is not possible, algorithms such as power ratio inversion or Gram-Schmidt are used. These techniques tend to invert the relative powers of signals arriving at the array, and thus are effective when the interference is substantially stronger than the desired signal. However, when signal levels are close, such techniques fail. This paper presents analytic and modelling studies of the eigenvector weighting technique. It is shown that this technique performs substantially better than power ratio inversion techniques. Like the power ratio inversion methods, eigenvector weighting is most effective when there is a large separation in signal powers. However, even when the signals are close in power, satisfactory cancellation can be achieved with eigenvector weighting for a large fraction of cases. The actual performance depends on array geometry and number of elements.

Descriptors :   *COMMUNICATION AND RADIO SYSTEMS, *RADIO ANTIJAMMING, *MULTIPATH TRANSMISSION, *RADIO SIGNALS, ALGORITHMS, ANTENNAS, ARRAYS, CANCELLATION, EIGENVECTORS, GEOMETRY, INTERFERENCE, INVERSION, POWER, RATIOS, SEPARATION, SIGNALS, ELECTROMAGNETIC WAVE PROPAGATION, NOISE(RADIO), ANTENNA ARRAYS, RADIO INTERFERENCE, REPRINTS, SYMPOSIA.

Subject Categories : Radio Communications
      Radiofrequency Wave Propagation
      Radio Countermeasures

Distribution Statement : APPROVED FOR PUBLIC RELEASE