| For college students, modern communication technology drew higher demand in engineering design and hardware implementation capability. Due to lack of proper communication experimental platform, most of the university’s experiment related to wireless communication is demonstration experiments. Therefore,building a wireless communication experiment platform has significant implications for developing the students’ ability of innovation, design and engineering, and strengthening students’ understanding of knowledge in the field of wireless communications.This paper accomplished the design of the wireless multichannel communication experiment platform which works at 2.4 2.48 GHz frequencies. The experiment platform is designed to be composed of several modules such as frequency synthesizers, transceiver RF front-end, demodulation, digital processing and control circuit constitute. All modules constitute a complete wireless communication system.This design of experiment platform using modularized thought. Transceiver RF front-end structure use low level of integration of super-heterodyne structure. Each functional circuit use separate module implementation. It’s useful for students to design experiments. Using fractional-N PLL frequency synthesizer technology, the local oscillator signal is realized. PLL frequency synthesizer technology can both reduces the steps and increase low noise performance of frequency source. PLL frequency synthesizer has a great significance to enhance the sensitivity of receiver. Using up/down frequency conversion to realize IF and RF carrier frequency conversion, which reduced the difficulty of implementation the RF front-end. Using orthogonal demodulation to realize FPGA baseband signal and IF signal conversion, which achieve high efficiency of signal transmission and compatible with other different ways of transmission.Based on the test of hardware of the system function and performance, we know that frequency synthesizers can achieve the low phase noise of-95dBc/Hz@ 1KHz, the receiver can realize the dynamic range of 69 dB, and indoor communication distance can be more than 22 m, So the platform can be able to achieve the requirement of index. |
