[Discuss-gnuradio] about gps lock

[Zan Li]

Dear all,

I meet a problem about the gpsdo for lock. First I check the usrp->get_mboard_sensor("gps_locked",0); it indicates the gps is locked. Then the program is sleep for 5 mins. Then I check the gps again but in this time it does not lock. I do not think that in this 5 mins the gps lost lock because every time I try like this, the first time it is locked but after 5 mins it is unlocked, as follows:


The reference clock is:GPS lock status: locked
Setting device clock source to:external
Setting device clock rate to:1e+08
Setting time source to:external
The reference clock is:GPS lock status: unlocked

UHD Warning:
    get_time: ValueError: get_nmea(): no GPRMC message found

UHD Warning:
    get_time: ValueError: get_nmea(): no GPRMC message found

(Here I can not read the gps time from the gpsdo, I think it is because the gpsdo does not lock).

Does anybody meet the similar problem? Any suggestion would be appreciated.

Best regards

Zan