	US 7,489,269 B2
	Method and apparatus for combining measurements and determining clock offsets between different global navigation satellite systems
Frank van Diggelen, San Jose, Calif. (US); and Javier De Salas, Madrid (Spain)
Assigned to Broadcom Corporation, Irvine, Calif. (US)
Filed on Dec. 20, 2006, as Appl. No. 11/642,267.
Application 11/642267 is a continuation in part of application No. 11/428218, filed on Jun. 30, 2006.
Application 11/428218 is a continuation of application No. 11/083541, filed on Mar. 18, 2005, granted, now 7,095,368, filed on Aug. 22, 2006.
Prior Publication US 2009/0009386 A1, Jan. 08, 2009
This patent is subject to a terminal disclaimer.
Int. Cl. G01S 1/02 (2006.01)

U.S. Cl. 342—357.01 [342/357.12]

20 Claims

1. A method of processing satellite signals from a first satellite navigation system and a second satellite navigation system, comprising:

measuring at least one first pseudorange between a satellite signal receiver and at least one satellite of said first satellite navigation system;

measuring at least one second pseudorange between said satellite signal receiver and at least one satellite of said second satellite navigation system;

obtaining a first difference between a first time reference frame of said first satellite navigation system and a time reference;

obtaining a second difference between a second time reference frame of said second satellite navigation system and the time reference; and

combining said at least one first pseudorange and said at least one second pseudorange using said first and second differences.