SYNCHRONIZED MEASUREMENT SAMPLING IN A NAVIGATION DEVICE

摘要

In a hot start mode of a navigation device, the process of obtaining pseudo-range measurements can be synchronized with processes of tracking navigation satellites and initializing a positioning unit to compute a position, velocity, and time (PVT) solution. 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.