Time-code assisted low-power GNSS single-shot receiver for mobile devices

The scope of this paper is a new approach to assisted navigation using both signals from a global navigation satellite system (GNSS) and a long-range time code transmitter. The information gathered from the time code signal gives a priori knowledge of signal reception time in the sub-microsecond range. Together with the approximate position of the device and assistance navigation data, both derived from a cellular network, a pre-estimation of code-phases is possible. This leads to a significant reduction in baseband processing effort for the computation of the real code phases for the navigation solution. The structure of the time code signal gives the opportunity to reuse the core of the baseband signal processing of the GNSS single-shot receiver with only minor modifications to determine the reception time. Therefore the number of cross correlation channels in the baseband processing hardware can be reduced by at least a factor of two.