Abstract: A GPS receiver includes an RF section and a digital section, the digital section including a correlator circuit for performing correlation with respect to a plurality of satellite channels. The GPS receiver is operated by cycling power to the RF section on and off according to a determined duty cycle having an ON portion and an OFF portion. During the ON portion, navigation related data received from the plurality of satellite channels is sampled by higher level software. Continuity of function may be achieved by resetting a state of at least a portion of the correlator circuit in correspondence to a transition from the OFF portion to the ON portion.

Abstract: In a hot start mode of a navigation device, the process of obtaining pseudo-range measurements can be synchronized with the processes of tracking navigation satellites and initializing a positioning unit to compute a position, velocity, and time (PVT) solution of the navigation device. This can influence a time instant at which the pseudo-range measurements are determined and a time to first fix, depending on whether the navigation device is in a strong or weak signal environment. A measurement unit can receive a first indication that a predetermined number of navigation satellites have been acquired and that navigation signals transmitted by the acquired navigation satellites have been locked. The measurement unit can receive a second indication that the positioning unit has been initialized to compute the PVT solution. In response to receiving both indications, the measurement unit can obtain the pseudo-range measurements. Accordingly, the positioning unit can compute the PVT solution.

Abstract: In a hot start mode of a navigation device, the process of obtaining pseudo-range measurements can be synchronized with the processes of tracking navigation satellites and initializing a positioning unit to compute a position, velocity, and time (PVT) solution of the navigation device. This can influence a time instant at which the pseudo-range measurements are determined and a time to first fix, depending on whether the navigation device is in a strong or weak signal environment. A measurement unit can receive a first indication that a predetermined number of navigation satellites have been acquired and that navigation signals transmitted by the acquired navigation satellites have been locked. The measurement unit can receive a second indication that the positioning unit has been initialized to compute the PVT solution. In response to receiving both indications, the measurement unit can obtain the pseudo-range measurements. Accordingly, the positioning unit can compute the PVT solution.