Method and apparatus for providing a time adjustment to a wireless communication system

In a wireless communication system, comprising at least a first and a second base transceiver station, a method for providing a time adjustment to the second base transceiver station, the method comprising the steps of:

• receiving an identity of the first and second base transceiver station at a mobile station, wherein the step of receiving the identity comprises the step of receiving a first base station identity number and a first PN short code time offset of the first base station transceiver, and a second base station identity number and a second PN short code time offset of the second base station transceiver, wherein the second base station transceiver adjusts a timing such that the second base station transceiver is unsynchronized in time to the first base station transceiver;
• tracking a first signal from the first base transceiver station and a second signal from the second base transceiver station by the mobile station, based on the identity, to yield a first and second time offset, wherein the step of tracking the first signal by the mobile station comprises the steps of:
• acquiring a pilot channel of the first signal from the first base station transceiver via a first signal strength measurement and correlation to a PN short code time offset by the mobile station;
• decoding a sync channel of the first signal to verify the first base station identity number via coherent demodulation provided by the pilot signal;
• enabling a phase lock loop algorithm in the mobile station to begin adjusting a local oscillator frequently of the mobile station to synchronize to an oscillator frequency of the first base station transceiver;
• initiating a timer in the mobile station upon enabling the phase lock loop algorithm;
• freezing the phase lock loop algorithm upon expiration of the timer, thereby yielding a stable free running local oscillator frequency in the mobile station which is substantially equal to the oscillator frequency of the first base transceiver station;
• extracting a first time offset from the first signal by a mobile station controller;
• and
• terminating tracking of the first signal by the mobile station;
• determining a timing adjustment calculation based on the first time offset of the first signal and the second time offset of the second signal by the mobile station;
• and
• transmitting the timing adjustment calculation to the second base station transceiver.

In a wireless communication system, comprising at least a first and a second base transceiver station, the first base transceiver station synchronized to a system reference time, and the second base transceiver station unsynchronized to the system reference time, the system reference time including a system reference oscillator frequency and an absolute reference time, a method for providing wireless communication system synchronization to the second base transceiver station, the method comprising the steps of:

• receiving an identity of the first and second base transceiver station at a mobile station, wherein the step of receiving the identity comprises the steps of:
• receiving a first base station identity number and a first PN short code time offset of the first base station transceiver;
• receiving a second base station identity number and a second PN short code time offset of the second base station transceiver;
• receiving a first distance between the first base transceiver station and the mobile station, and;
• receiving a second distance between the second base transceiver station and the mobile station;
• tracking a first signal from the first base transceiver station by the mobile station, based on the identity;
• synchronizing the mobile station to the system reference time via the first signal;
• determining an actual time offset with respect to the absolute reference time, of a second signal from the second base transceiver station by the mobile station;
• and
• based on the actual time offset, synchronizing the second base transceiver station to the system reference time.

In a wireless communication system, comprising at least a first and a second base transceiver station, the first base transceiver station synchronized to a system reference time, and the second base transceiver station unsynchronized to the system reference time, the system reference time including a system reference oscillator frequency and an absolute reference time, an apparatus for providing wireless communication system synchronization to the second base transceiver station, the apparatus comprising:

• means for conveying an identity of the first and second base transceiver station;
• a mobile station adapted to receive the identity, the mobile station comprising
• a mobile station receiver adapted to track a first signal from the first base transceiver station and a second signal from the second base transceiver station, based on the identity, and to synchronize the mobile station to the system reference time via the first signal, wherein the mobile station receiver further comprises:
• means for acquiring a pilot channel of the second signal from the second base station transceiver via correlation to a short code;
• and
• means for decoding a sync channel of the second signal to verify the first PN short code time offset and the second base station identity number via coherent demodulation provided by the pilot signal;
• and
• a mobile station controller adapted to determine an actual time offset with respect to the absolute reference time, of the second signal, calculate a timing adjustment calculation based on the actual time offset, and coordinate transmission of an access channel message, the access channel message comprising the timing adjustment calculation;
• a second base transceiver station receiver for reeving and acknowledging the access channel message;
• and
• a second base transceiver station phase lock loop algorithm for producing a correction signal based on the timing adjustment calculation, the correction signal synchronizing the second base transceiver station to the system reference time.

In a wireless communication system, comprising at least a first and a second base transceiver station, the first base transceiver station synchronized to a system reference time, and the second base transceiver station unsynchronized to the system reference time, the system reference time including a system reference oscillator frequency and an absolute reference time, an apparatus for providing wireless communication system synchronization to the second base transceiver station, the apparatus comprising:

• a means for conveying an identity of the first and second base transceiver station;
• a mobile station for receiving the identity, the mobile station comprising
• a mobile station receiver for tracking a first signal from the first base transceiver station and a second signal from the second base transceiver station, based on the identity, and
• synchronizing the mobile station to the system reference time via the first signal,
• a mobile station controller for determining an actual time offset with respect to the absolute reference time, of the second signal,
• calculating an timing adjustment calculation based on the actual time offset, and
• coordinating transmission of an access channel message the access channel message comprising the timing adjustment calculation;
• a second base transceiver station receiver for receiving and acknowledging the access channel message;
• and
• a second base transceiver station phase lock loop algorithm for producing a correction signal based on the timing adjustment calculation, the correction signal synchronizing the second base transceiver station to the system reference time.