Research Of GPS Baseband SoC Design And Key Technology

With the continuous development of U.S. GPS (Global Positioning System) andother Global Navigation Satellite Systems (GNSS), Satellite navigation is widely usedin the area of military, transportation, mapping, time service, etc. The requirement forthe receiver’s performance is increasing constantly. High integration, high performanceand low-power are the development trend of the receiver, making receiver basebandchip design more and more difficult. On the other hand, with the development of VeryLarge Scale Integration (VLSI) technology, System-on-Chip (SoC) and reusable IP coretechnology become the mainstream of integrated circuit solution. So there is greatsignificance for the development of SoC based GNSS receiver.This thesis, ground on the research of GPS system and receiver, describe ourdesign of the baseband SoC chip，which aims at researching and implementing thebaseband signal processing for GPS. After comparing the typical acquisition method,we proposed a segment accumulating and parallel-frequency-acquisition method toimprove the performance. The signal tracking loop was realized base on delay-lockedcode loop and Costas carrier loop. Based on the signal acquisition and trackingalgorithm, we chose the ARM9core and AMBA as MCU and on chip bus for ourbaseband SoC design, We implemented the function of the GPS receiverby bothhardware and software.The main functions of hardware included digital down conversion, local carriergeneration, local C/A code generation, C/A code correlation and synchronous counter.Every hardware module was implemented at register transfer level and verified by RTLsimulation. The software realized the initialization and control, data reading andhandling, acquisition detection, tracking loop calculation and synchronous processing.For system level verification, we used the MAX2769chip as IF signal source, and weused the SoC verification board with ARM9+FPGA as GPS baseband SoC verificationplatform to integrate the software and hardware.