Possible spotted null forming by ESPAR antenna

摘要

Although the ESPAR antenna has only single-port output, maximum ratio combining of the received signals is found to work as well as it does for DBF adaptive arrays. The space correlation coefficient between arriving waves is expressed in a form that includes the electromagnetic coupling among the elements of the antenna. It is indicated that the distribution of the space correlation in a zone of an indoor space corresponds to the number of reflection passes. Adaptive control of the ESPAR antenna at a point whose space correlation is low results in a high output SINR above 15dB.