A method and a system for a location determination (a) acquire a first
positioning signal; (b) analyze the first positioning signal to provide
an estimate of a clock signal acceleration; (c) acquire additional
positioning signals based on the estimate of the clock signal
acceleration; and (d) perform the location determination using the first
positioning signal and the additional positioning signals. The additional
positioning signals may be acquired using a stacking technique. The first
positioning signal may be acquired based on a signal-to-noise ratio
exceeding a predetermined threshold. Clock signal acceleration may be
estimated using a constant clock signal acceleration parametric model,
which may be parabolic model based on a function that depends on the
clock signal acceleration, a clock Doppler and an initial phase value.
Alternatively, grids of various granularity may be searched clock signal
acceleration space and a clock Doppler space in the vicinity of a clock
Doppler value measured in the acquisition of the first positioning
signal.