Patent ID: 6166683
Filing Date: 2000-12-26
Classification: G01S

Abstract:
In an attitude determination system having a plurality of satellites and having first and second antennas, a method of detecting and correcting cycle slip in said system comprising:at a first processing epoch,measuring a first phase of a first carrier signal at said first antenna from a first satellite,measuring a second phase of said first carrier signal at said second antenna from said first satellite, andestablishing a first single difference from said first and second phases;at a second processing epoch,measuring a third phase of said first carrier signal at said first antenna from said first satellite,measuring a fourth phase of said first carrier signal at said second antenna from said first satellite, andestablishing a second single difference from said third and fourth phases;establishing a delta single difference from said first and second single differences;establishing a detection test statistic from said delta single differences;establishing a failure detection threshold using a geometry of said plurality of satellites and a false alert rate;comparing the detection test statistic to the failure detection threshold; anddeclaring existence of a cycle slip based on said comparing further comprising:at said first processing epoch,measuring a first phase of a second carrier signal at said first antenna from a second satellite,measuring a second phase of said second carrier signal at said second antenna from said second satellite; andat said second processing epoch,measuring a third phase of said second carrier signal at said first antenna from said second satellite,measuring a fourth phase of said second carrier signal at said second antenna from said second satellite,wherein said establishing a first single difference is established from said first and second phases of said first carrier signal and said first and second phases of said second carrier signal, andwherein said establishing a second single difference is established from said third and fourth phases of said first carrier signal and said third and fourth phases of said second carrier signal.