To get all the four Stokes parameters and ocean surface field, abroad band digital correlator used in polarization radiometer was introduced in the paper. Two high-speed A / D converter (ADC08D1500) are used to sample four signal channels at the same time with 1.2GHz sampling rate and 8 effective bits. The sampling results are operated in the newest Field-Programmable Gate Array (FPGA)-Virtex5 from Xilinx to make correlation calculation. The structure of interfacing circuit and control system of the main modules are presented in detail. The measure result is also given. The power of the whole system is 13.5W.