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The Assisted GPS (A‐GPS) concept was developed to improve the sensitivity and time to fix of a GPS receiver when compared to a stand‐alone GPS receiver. See [10] for an explanation of the A‐GPS concept. A‐GPS facilitates improved sensitivity by providing assistance in the form of ephemeris/almanac information to the receiver so that decoding is no longer required. In addition, assistance, in the form of a coarse/fine GPS time estimate and rough receiver position, enables the receiver to compute the list of visible satellites, rough satellite Doppler frequency, and code phase, thereby significantly reducing its acquisition search space.

Analogous to the assisted mode of GPS, an assisted mode can be considered for MBS as well. In A‐MBS mode, beacon information such as the almanac, any corrections, and atmospheric information may be transmitted over a cellular/other side channel. A list of visible beacons (based on the rough user position) can also be provided to the receiver to help reduce the PRN search space.