Synchronizing base stations in a wireless telecommunications system

Abstract

A technique for synchronizing the timing signals in the base stations of a wireless telecommunications system is disclosed. In accordance with the illustrative embodiment of the present invention, each base station derives the frequency of its timing signal from one periodic signal, but the phase of its timing signal from a second periodic signal. In general, the base station derives its timing signal based on: (1) the frequency of a reference timing signal, and (2) the phase of a feedback signal. The reference timing signal can be obtained from a common timing source or from different timing sources which are designed to have the same frequency. The feedback signal is advantageously the confluence of two feedback loops. In accordance with the first feedback loop, the feedback signal is based on the phase of the base station's own timing signal. In accordance with the second feedback loop, the feedback signal is based on the phase of the timing signals from one or more nearby base stations. Advantageously, the feedback signal is based on the Boolean AND or NAND function of the base station's own timing signal and the timing signals of the nearby base stations.