How to evaluate GPS sensitivity of nRF9160 if using active antenna?

[Ngoc Nguyen]

Dear Devzone,

At the moment, We do not have methods to measure the GPS sensitivity of our products based on nRF9160.

We are using an active antenna with LNA gain 16dB, NF 1dB.

The Schematic for the GPS part is like below.

We apply a Simulated GPS signal directly to J4. And the minimum level where nRF9160 still could fix coordinates is -129dBm.

Could we use this result including test report of external LNA (from Antenna active) to infer the sensitivity of the device? If yes, how to infer?

Thank you and Best regards,

Ngoc Nguyen

[JONATHAN LL]

Hi Ngoc Nguyen,

Would like to understand your setup a bit better:

1)  would measure s-parameters between ports P1 and P2 to see impedances and insertion loss (including the RF cable/pigtail connecting to UFL connector - as the connection and/or pigtail cable itself can be very un-robust/non-50ohm)




2) could you share waveform details for used "GPS signal"

3) also good to check (although least probable problem here) accuracy of GPS generator output level - is it calibrated by power meter or so?

Regards,
Jonathan