Synchronization of receiver and transmitter local oscillators for ranging applications

Abstract

A system and method for accurately determining the distance between two network devices using channel sounding is disclosed. Each network device guarantees a fixed phase relationship between the transmit and receive circuits. In one embodiment, this is accomplished by incorporating a frequency divider within a phase locked loop. The frequency divider can have a reset such that the frequency divider can be initialized to a predetermined state. Furthermore, by utilizing a frequency divider with a reset configured within the phase locked loop, the clock of the transmit and receive circuits that the quadrature signal generator outputs are guaranteed to have a constant phase relationship.

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