Design of high-speed digital correlator in fully polarimetric microwave radiometer

Abstract

Fully polarimetric microwave radiometer is a new type of passive microwave sensor for measuring ocean wind vector. Digital correlation technology is used in it to get all the four Stokes parameters of ocean emission in this paper. Digital correlator is the main part of fully polarimetric radiometer. In the paper, design of a novel digital correlator is presented. Two high-speed, dual A/D converters are used to sample four signals, and the sampling results are operated in FPGA-Vertex5 to make both self- and cross-correlation calculations. The test results of the correlator are given. The four channels are sampled at 360 MHz. For both 100 MHz and 150 MHz input, the correlation coefficient between the measurements and their ideal results is above 0.9999999. The whole power of digital correlator is 11.3 W.