Patent ID: 6570533
Filing Date: 2003-05-27
Classification: G01S

Abstract:
A method for determining the phase of information modulated in a code-modulated signal transmitted by a satellite, in a receiver (MS), wherein at least partly the same information is transmitted from at least a first and a second satellite (SV1-SV4) substantially simultaneously, the code-modulated signal transmitted from at least the first and the second satellite (SV1-SV4) is received, characterized in that in the method, at least the following steps are taken:a first acquisition step, in which the receiver is synchronized with the signal of at least the first satellite (SV1), a determination step, in which a moment of a bit change of an information data bit in the modulated signal of the first satellite (SV1) is used to determine the phase of information modulated in the signal, a computing step to compute the difference in propagation time of the signal transmitted by said first satellite (SV1) and the signal transmitted by the second satellite (SV2) from the satellite (SV1, SV2) to the receiver (MS), a second acquisition step, in which the receiver is synchronized with the signal of the second satellite on the basis of the difference in propagation time computed in the computing step, and an integration step to receive the signal of the second satellite and to integrate sequences of a certain length to improve the demodulability of the signal.