Design And Implementation Of Communication Master Station In ISM Band Based On Software Defined Radio

With the development of wireless sensor network technology,wireless transceiver in ISM(Industrial Scientific Medical)band are widely used in smart home systems,industrial measurement and control systems,agricultural monitoring systems and so on.As the central node of the system,the communication master station needs to communicate with the wireless transceiver of each slave node.Each slave node should select different transceiver reasonably according to the data traffic,data rate,power consumption,cost and other needs.However,due to the different performance of various transceivers,it is difficult to design a communication master station for the same communication system to be compatible with multiple transceivers.SDR has the characteristics of universal hardware,software-base function and expansibility,which can meet the design requirements of the communication master station.Based on the architecture of SDR,this paper designs and implements a multi-band,multi-standard,multi-channel embedded communication master station in ISM band.This paper also constructs a wireless transceiver with orthogonal sampling in broadband zero-IF.In the part of hardware design,this paper analyzes the component selection and circuit principle of analog signal processing board and digital signal processing board,including AD/DA circuit,RF front-end circuit and digital signal processing circuit.The digital signal processor adopts Xilinx ZYNQ-7020 to realize the hardware drive and digital communication algorithm.Xilinx ZYNQ-7020 integrates the software programmability of ARM processor and the hardware programmability of FPGA.In the part of software design,this paper analyzes modulation,demodulation,channelized transceiver,data transmission and underlying hardware driver.According to the communication requirements of wireless sensor network in ISM band,this paper designs a variety of commonly used modulation modules and demodulation modules.An efficient channelized transceiver module with complex signal is realized based on polyphase filtering technology.The module of high-speed data transmission between PL and PS and the module of AD/DA conversion are realized by using the hardware and software co-design methodology of FPGA and ARM in ZYNQ-7020.The RF front-end driver module is designed in ARM,which can set the hardware circuit according to the parameters of communication frequency,bandwidth,transceiver mode,etc.On the basis of completing the software and hardware design and debugging of communication master station in ISM band,this paper builds experimental systems composed of communication master station and different transceivers.The test results show that the communication master station can communicate with many wireless transceivers at the same time.The frequency range of the communication master station is 30MHz-6GHz.The modulation and demodulation methods of the communication master station are ASK and GFSK.The function and performance meet the requirements of wireless sensor network.By adding and upgrading software modules,the communication master station can further expand functions and meet various application requirements of wireless sensor network.