AZIMUTH MEASURING MONOPULSE RECEIVER USING 4-ARM DUAL MODE SPIRAL ANTENNA

摘要

PURPOSE:To decrease a measurement error by providing a phase correcting circuit, plural reference phase surface correcting circuits, and a change-over switch for switching the reference phase correcting circuit at every prescribed frequency band, between a mode forming circuit and a beam forming circuit. CONSTITUTION:A 4-arm spiral antenna 1 excites and receives simultaneously two beams of SIGMA mode and DELTA mode by combining it with a mode forming circuit 2. On the SIGMA channel of the output of the circuit 2, plural reference phase surface correcting circuits 3 are provided, and selected alternatively by switches K1-K4. That is to say, by the switches K1, K2, one line among lines L1-L3 being phase correcting circuits is selected, and by the switches K3, K4, one phase shifter among phase shifters PS1-PS3 is selected. In this regard, in accordance with a channel to be selected, the switches K1-K4 are interlocked and switched. Also, the line length of each line L1-L3 and the phase shift quantity of each phase shifter PS1-PS3 are set at every frequency band, and the output of the circuit 2 is sent to a beam forming circuit 4 through the circuit 3, processed, and values S1-S4 are outputted.