O. V. Afanasyev, I. S. Dmitriev

Article is devoted an estimation of efficiency 3 channel phase direction finders with a пятиelement ring antenna array from not directed antenna elements and the antenna switchboard, allowing to measure 4 differences of phases on a array ring in two steps. It is shown, that such direction finder has non-uniform on a circle direction finding sensitivity and loses to a usual трехchannel direction finder with a трехelement antenna array of the same radius to 5,4dB at direction finding along an axis on which there is the general for two phase measurements an antenna element, at an insignificant prize in case of direction finding along a perpendicular axis. In this size of loss 3dB are caused by necessity of doubling of general time of supervision of a signal for 2 positions of the antenna switchboard. Other loss and dependence of sensitivity of a direction finder on an arrival direction are caused by specificity of correlation communications between errors of phase measurements in various steams of a direction finder at non-simultaneous and incomplete measurement of differences of phases. The expediency of application of such direction finder is caused by its wide strip: at identical radiuses of antenna arrays abnormal errors of direction finding in a direction finder with a пятиelement array appear on working frequencies, more than in 3 times exceeding similar frequencies for a direction finder with a трехelement array. Work contains 2 drawings and 4 bibliographic sources of the information.