Vehicle-mounted satellite signal receiving system

摘要

A vehicle-mounted satellite signal receiving system adopting a satellite tracking system combining gyro tracking and hybrid tracking is disclosed which can correct a sensitivity coefficient for correcting a gyro sensor output signal to make up for a sensitivity error, even when a drift is produced in the sensitivity error. In this system, gyro tracking is caused when the received power level is above a threshold power level. The gyro tracking is done by determining the angular velocity omega of an antenna as omega = -( omega G x DELTA SB + omega G from a value obtained by inverting the sign of the product of a gyro tracking angular velocity omega G and a sensitivity coefficient DELTA SB for dealing with the sensitivity error and a predetermined offset error correction value omega G and setting the antenna to omega . When DELTA SB is inaccurate and a sensitivity error is generated in the gyro sensor output signal, the received power level is reduced. When the received power level becomes lower than a threshold power level LB, the sensitivity coefficient is corrected on the basis of the sense of the angular velocity omega S in the hybrid tracking (step tracking) and in the gyro tracking. <IMAGE>