The Research And Implementation Of Binary Offset Carrier Modulation Based Code Division Multiple Access Signal Tracking Technology

Global Navigation Satellite System, GNSS, including the US Global Position System(GPS), European Galileo and Chinese Beidou, have proposed their mordernized programs. In these programs, the Binary Offset Carrier(BOC) modulated Code Division Multiple Access(CDMA) signal is widely used as the main modulation stheme to make full use of the allocated frequency resource and improve the navigation and positioning performance. However, with the introduction of the BOC modulation based CDMA signal, the complexity of satellite navigation system, especially the requirement for the GNSS receivers. In this paper, the main target is to design the tracking method of BOC modulation based CDMA singal according to the conditions in the receiver design so as to provide the accurate meansurement for the positioning of multiple system and frequency.Firstly, the time domain waveform, generating method, autocorrelation function and power spectrum density of the widely used BOC signal, like standard BOC singal, AltBOC singal and MBOC signal, are analyzed. The typical BOC signal tracking method is reviewed.The signal tracking performance, complexity and the compatibility of different BOC singals are also evaluated for these methods.Secondly, the compatible tracking methods of BOC modulation based CDMA singal are proposed. According to the requirement of complexity and tracking performance, the low complexity compatible tracking method and high performance trakcing method are designed. With the help of the proposed method, different BOC signals can be processed by the single structure. In the low complexity method, different BOC signals are divided into two groups which are high order BOC and low order BOC to greatly simplify the system. In the high performance method, the tracking loop of each BOC signal is specially designed so as to obtain the best trakcin performance. Furthermore, the two tracking method is realized in the hardware. The whole structure, the mian hardware model and the software are developed in the paper.Finally, by using the GNSS signal simulator, the proposed low complexity method and high performance method are tested with real data. The test results are listed and analyzed which validate the applicable of the proposed methods...