摘要 |
Methods, systems and mobile stations are provided which determine GPS timing by collecting energy from transmitted signals from one and preferably more acquired satellites to determine a single timing value, which may increase sensitivity. In addition, the receiver devices may use the entire navigation message from each satellite to obtain timing information which may further improve sensitivity and possibly remove latency from having to wait for the time-of-week (TOW) field to be received in the GPS satellite transmission. This is preferably accomplished by maximizing a single delay metric created based on expected (known in advance from some source) and actual (received) navigation symbols from the acquired satellites. As a result, position fixes may possibly be obtained under disadvantaged conditions where the signal quality from the GPS satellites is poor. Furthermore, the timing information obtained pursuant to the present invention does not require a timing relationship between GPS and communication network time.
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