Broadband DDC based on polyphase filter and its FPGA implementation

Digital Down Conversion (DDC) is one of the key technologies for software radio, which converts high frequency data streams into low frequency data streams for easy subsequent real-time processing by DSP devices. This paper presents a under the digital frequency conversion method based on polyphase filtering. Using Field Programmable Gate Array (FPGA) under the high speed digital frequency conversion was implemented, and introduced including Numerical Controlled Oscillator(NCO), frequency mixing module, CIC filter, HB filters, FIR filter, are discussed in detail. Meanwhile, use the software radio platform of my laboratory and the chipscope to collect data, and use the Matlab analyze the data, to verify the correctness and feasibility of the theoretical simulation.