Cognitive Radio Haedware Platform Design And Implementation

The importance of wireless communication becomes increasingly prominent in people's daily lives and people's demand for wireless communications are increasingly high. However, the allocation of radio spectrum resources are exhausted while the wireless communications is booming. In order to solve the problem of spectrum resources' shortage, cognitive radio concepts have been proposed. This thesis' topic is cognitive radio hardware platform design and implementation.The digital signal processing system is designed and implemented as a part of cognitive radio hardware platform in this paper, including the Numerically Controlled Oscillator Module NCO, a digital signal down-conversion module, FIR filter based on the DA algorithm, FFT module design and implementation. This article summarized the main points of work and innovation as follows:1) Designed the NCO module based on mixer theory and the actual situation of the project using the method of look-up table and be verified.2) Studied the digital down-conversion technology, expounded multi-rate signal processing theory, extract and interpolation theory, integrator comb filter (CIC filter), etc., and designed and implemented the CIC filter for digital conversion.3) Using a distributed algorithm (DA algorithm) completed the FIR filter design. Using cascade-pipeline structure achieved a 256-point Fast Fourier Transform, which saved resources and improved the calculation speed of digital chips.4) Designed the configuration circuit of digital chip.In the design, there is no multiplier for the CIC filter, it is suitable for high-speed digital signal down-conversion; in FPGA implementation process using a distributed algorithm FIR filters, it not only saves resources and has high performance/resource consumption ratio, but also increases the computing speed and reduce the system delay; using cascaded-pipeline structure designed the FFT modul which can improve the computing speed, while don't occupied by a lot of system resources, achieve a good balance between performance and resource consumption. In addition, in this paper the author optimized the entire system design.