Patent ID: 6044276
Filing Date: 2000-03-28
Classification: H04B

Abstract:
A method in a messaging system having a plurality of base transmitters, the method for limiting an interval of carrier cancellation at a reception point during a simulcast transmission, the method comprising the steps of:providing a plurality of pseudorandom sequence generators for the plurality of base transmitters, the plurality of pseudorandom sequence generators arranged to ensure that they generate a plurality of pseudorandom sequences having sub-sequences that are different from one another during concurrent transmissions by the plurality of base transmitters;continuously dithering a parameter selected from at least one of a carrier frequency, a carrier phase, and a carrier amplitude, of the plurality of base transmitters in accordance with the plurality of pseudorandom sequences during the simulcast transmission from the plurality of base transmitters; andprior to the dithering step, further arranging the plurality of pseudorandom sequence generators to adjust a duration of dithers of said parameter to a length selected to limit the interval of carrier cancellation to a predetermined period, thereby allowing an increased benefit from a forward error correction code utilized in the messaging system.