METHOD FOR CONTROLLING ARRAY ANTENNA, METHOD FOR CALCULATING SIGNAL TO NOISE RATIO OF RECEIVED SIGNAL, AND METHOD FOR ADAPTIVELY CONTROLLING RADIO RECEIVER

摘要

PROBLEM TO BE SOLVED: To adaptively control an array antenna whereby a main beam is directed in a direction of a desired wave being a directivity of the array antenna and a null is directed in a direction of an interference wave.;SOLUTION: An m-phase PSK modulation signal is a transmitted radio signal. Based on a received signal y(t) received by a radiating element A0 of an ESPAR antenna system 100, an adaptive controller 20 calculates and sets a reactance value of each of variable reactance elements 12-1 to 12-6 for directing a main beam of the ESPAR antenna system 100 in a direction of a desired wave and directing nulls in directions of interference waves so that a value of an objective function (Formula 14) being a function of resulting from dividing the (1/m)-th power of an absolute value of an average value of the m-th power of the received signal for a prescribed period by the (1/2)th power of an average of an absolute value of the square of the received signal becomes the maximum by using an iterative numerical solution of a nonlinear programming method such as the maximum grade method.;COPYRIGHT: (C)2004,JPO