Simulation Of MBOC Signal And Its Design And Implementation Of Acquisition

With the development of GNSS(Global Navigation Satellite System), frequency ismore and more crowded, in order to achieve the spectrum separation, BOC signal isgenerated. MBOC signal is a new way of signal modulation be consisted of many BOCsignal and applied to GPS L1C、GALILEO E1B/C and BDS B1C. AutocorrelationMBOC exist multiple structure, a multi-peak structure such correlation peak associatedsharper, with the potential to achieve higher synchronization accuracy, while increasing thecomplexity of the synchronization. For MBOC signal multimodal characteristics, MBOCsignal acquisition algorithms are studied, the main contents include:(1) The modulation methods, classic power spectral density and auto-correlationfunction of BOC and MBOC signals are studied, And summarizes the characteristics of thepower spectral density and autocorrelation function of MBOC signal. Code trackingprecision of the two signals are analyzed and compared.(2) Based MBOC modulation theory, MBOC digital IF signals are designed andimplemented, and the results were compared with the theoretical simulation;(3) At home and abroad MBOC signal acquisition algorithm is a new research,including double-sideband, BPSK-like, subcarrier elimination algorithm. However, thesealgorithms drawbacks of energy loss and hardware resource requirements higher. Therefore,the article designed an improved auto-correlation side peaks cancellation technology(ASPeCT), and algorithm was simulated. The results show that the algorithm can solveMBOC signal appears at the wrong time of capture fishing, drain catch, capture a long timeand resource-intensive;(4) Based on FPGA ASPeCT MBOC (6,1,1/11) signal acquisition is design andimplementation, focusing on the carrier NCO, down-sampling process, the spreading codegeneration, direct folding type matched filter and signal detection module. Use resultingMBOC IF signal, ASPeCT’s acquisition program was tested and verified the feasibility andcorrectness of the capture system.For MBOC signal characteristics and acquisition algorithm research can providetheoretical guidance and practical reference for navigation receiver terminal study hasimportant significance.