摘要 |
To determine the delay between true GPS time and the arrival time of a CDMA signal, a GPS receiver generates a first reference signal that is locked to true GPS time, and applies this signal to a CDMA base station test equipment. The CDMA base station test equipment receives the CDMA signal and generates a second reference signal which has transitions occurring substantially concurrently with transitions of an internal synchronization clock used to sample the first reference signal. The CDMA base station test equipment provides the delay between the second reference signal and the CDMA signal. A frequency/time counter provides the delay between the first reference signal and the second reference signal. The sum of the delays supplied by the CDMA base station test equipment and the frequency/time counter represents the delay between true GPS time and the CDMA signal. |