The Design Of2.4GHz Wireless Sensor Networks Zigbee Baseband

Wireless sensor network is a self-organization network by large number of sensor nodesthrough wireless communication technology. In recent years, with the rapid development andwide application of computers, wireless communication and network technology, the wirelesssensor networks become a concern in the international forefront, and become a hot area ofresearch. The ZigBee IEEE802.15.4is an important protocol in wireless sensor network,ZigBee have the Significant features, such as low speed, low power, low-cost, safe and reliable,could be used in smart home, industrial control, intelligent transportation and construction,health care and other aspects. This paper based on the2.4GHz ZigBee IEEE802.15.4protocol,realize the ZigBee baseband design on the platform of FPGA.In the completion of this paper, firstly, use matlab build the transmitter and receiverstructure model and simulation, followed by designing the RTL circuit and verify itsfunctionality and timing, then is the circuit board design. In hardware select, we choose XilinxSpartan-3A DSP FPGA, which integrated Xtreme DSP^TMcore and can deal with complexdigital signal processing, while using the company ADI’s three-chips to achieve the entiresystem, three chips are clock management chip AD9516, analog-digital converter chip AD6655,digital-analog converter chip AD9777. Based on2.4GHz ZigBee protocol, the transmitterincluding three parts, bit symbol conversion, symbol numbers conversion, OQPSK modulation.Because of There is no clearly defined in the structure of the receiver in the protocol, so thereceiver design is a core part in this thesis. Receiver include packet inspection, precision timing,down-sampling, frequency offset estimation, frequency offset correction, de-spreading， theprecision timing, down-sampling, frequency offset estimation are the most important unit inreceiver.At last, make spectral analysis between the data of the transmitter send and the data of thereceiver received by matlab, the spectrum of the two sets of data are basically the same not onlyin central frequency, but also in band wide, so it can be concluded that this thesis successfullyrealize the objective of design a2.4GHz ZigBee baseband through the FPGA platform. Insummary, this paper using the FPGA resources implement the ZigBee physical layer transmitterand receiver design, the digital signal processing functions are implemented by FPGA, whichsaved dedicated digital signal processing hardware resources and design area, achieved thedesired design objectives.