Spreadtrackingtechnolonoy Based On FPGA

Voice and video conference communication system’s overall goal is to build a multi-user, high real-time, reliable, flexible, portable conference system that can simultaneously accommodate multiple users access to long-term use, and adapt to the future development of multimedia conferencing requirements. In this paper, chip synchronization throughout the system planning, design, made a thorough research.In this system, through the experience gained in subsequent meetings to promote more communication applications, with reference. This article will spread spectrum communication theory and integrated circuits by combining conference communication system chip tracking simulation, construct, implement programs to achieve a conference communication tracking module, for receiving signals properly restored foundation.In this paper, spread spectrum communication technology-based communications systems perspective elaborated tracking chip design ideas, as well as the overall framework for the design of hardware programming. Overall mainly includes four parts:the delay-locked discriminator, loop filter, VCO and spreading code generators and other parts. Delay-locked discriminator FPGA as the control center section, using using advanced hysteresis gate and a phase detector contained in the signals to obtain the phase difference and the correlation algorithm to compare. Loop filter for low-pass filtering the phase difference and optimized design, mainly to complete the voltage controlled oscillator to the frequency conversion and digital error NCO; spreading code generator module also includes DDS signal source section and the code generating section chip. Each module has a corresponding design flow diagram, using VHDL/Verilog its programming language and system debugging Span6FPGA-based signal processing platform to achieve this loop.System debugging results show that by Matlab and Modelsim simulation results verified by comparing tracking loop allows chip phase stable at-1/4to1/4of the error range, verify the. tracking loop design and communication flow is reasonable, to ensure follow-up module accurate demodulation reduction, reliable, real-time communication purposes. Simulation parameters through the ring and resource consumption analysis, design optimization suggestions given to. tracking loop has a reference. Also this module can also be adjustable parameters, which can achieve system availability. In summary, the design of the tracking loop instrument with a scalable, save hardware resources and other characteristics, with a strong practical significance.