Packaging test-fixture research for 10-12 GHz frequency detector based on thermoelectric microwave power sensor

To show the performance of a 10-12 GHz frequency detector embedded into real-life RF communication circuit systems, a packaging test-fixture research is presented. The principle of the frequency detector is based on the phase delay detection of two separated signals divided by a two-way Wilkinson power divider. The phase delay is proportional to the frequency of the input microwave signal and gives rise to variation of output power. The thermoelectric microwave power sensor is adopted to measure the variation. In this design, the packaging method is based on the transition of the input CPW- based port of the frequency detector, a microstrip line and an SMA connector. Fabrication of the package is performed and the layout size of the packaging test-fixture is 40 × 30 mm². Experiments show that whether before or after the packaging, the measured output thermovoltages both approximate to decrease linearly with respect to the frequency of the RF signal. The after-packaging sensitivities are 0.031, 0.104 and 0.317 μV·MHz^-1 under RF signals of 10, 15 and 20 dBm, respectively, while the before-packaging sensitivities are 0.030, 0.103 and 0.305 μV·MHz^-1, respectively.