A study of phase/amplitude calibration method for six-port direct conversion receivers

摘要

The measurement method of the reflect coefficients using a six-port junction that G.F.Engen proposed, has produced many circuit configuration and calibration method till today. The six-port junction is used originally as a measurement instrument for finding reflect coefficients, in these days there are attempts to use the six-port junction as a down converter for receivers. If the six-port circuit is used for receivers, there are antennas, filters, and low-noise amplifiers, thus we cannot calibrate using the sliding load and standard load. We did down conversion experiments using a fabricated six-port circuit, and the calibration concept is based on dual-tone calibration method. We acquired the resultant constellation pattern at 1.9, 2.4, and 5.8 GHz.