Method and system for facilitating timing of base stations in an asynchronous CDMA mobile communications system

A method for facilitating timing between mobile stations and base stations in an asynchronous mobile telecommunications network, comprising the steps of:

• receiving relative timing difference data from each of a plurality of mobile stations, the relative timing difference data from each mobile station including a measured difference between the time bases of at least two base stations as measured by said mobile stations;
• determining a relative timing difference estimate based on the received relative timing difference data, the relative timing difference estimate representing an estimate of a difference between the time bases of at least two base stations;
• accounting for propagation delays between a measuring mobile station and the at least two base stations of which the time base difference is measured in said relative timing difference estimate;
• storing the relative timing difference estimate in a relative timing difference table;
• transmitting the relative timing difference estimate to a receiving mobile station.

An asynchronous mobile telecommunications system, comprising:

• a plurality of base stations for transmitting data to and receiving data from a plurality of mobile stations, the plurality of base stations individually receiving relative timing difference data, the relative timing difference data from each mobile station comprising a measured difference between the time bases of two of the plurality of base stations as measured by the mobile station;
• a register storing a relative timing difference table, each of a plurality of entries in said table comprising a relative timing difference estimate calculated from the relative timing difference data and said register storing error data for each relative timing difference estimate;
• and
• wherein a first one of the plurality of base stations transmits a relative timing difference estimate to a receiving mobile station to facilitate timing of communications between the mobile station and a second one of the plurality of base stations.

A method for facilitating the timing of a plurality of base stations in an asynchronous mobile communications system, comprising the steps of:

• at least one of said plurality of base stations sending at least one estimated relative time difference value to a mobile station, said at least one estimated relative time difference value comprising an estimated timing difference between said at least one of said plurality of base stations and a neighbor base station;
• said mobile station receiving said at least one estimated relative time difference value;
• said mobile station correlating said at least one estimated relative time difference value with a matched filter output signal;
• and
• initiating a cell search based on a result of the correlating step.

A method for facilitating the timing of a plurality of base stations in an asynchronous mobile communications system, comprising the steps of:

• at least one of said plurality of base stations sending at least one estimated relative time difference value to a mobile station, said at least one estimated relative time difference value comprising an estimated timing difference between said at least one of said plurality of base stations and a neighbor base station;
• said mobile station receiving said at least one estimated relative time difference value;
• and
• determining an approximate position of the mobile station using said at least one estimated relative time difference value.

A system for synchronizing a plurality of base stations in a mobile communications system, comprising:

• a first base station of said plurality of base stations, said first base station operable to broadcast or transmit at least one estimated relative time difference value, said at least one estimated relative time difference value comprising an estimated timing difference between said first base station and a neighbor base station;
• a mobile station for receiving said at least one estimated relative time difference value;
• and
• a processor for determining an approximate position of the mobile station using said at least one estimated relative time difference value.