Variable GPS period fix interval. Best way to do it?

[HoovinSchoovin]

Hello, 

I am currently researching the best way to be able to change the rate at which I fetch a GPS fix. I want to start the program at 60 seconds, then depending on environmental variables I want to decrease to every ten seconds. 

Is this possible and is there a best way to do it? I see there being 2 options. 

1) Firstly, I could independently call a single GPS fix at every X seconds without having to worry about any intervals. 

2) I could use intervals, then restart the GPS every time that i want to change the interval. 

To maximise accuracy and minimise time to fix, what would be the recommended way to get variable rate fixes, or is there any other way i am not thinking about?  

Any help or advice would be very appreciated. 

Im using v2.6.1 and on a nrf9161 DK. 

Thank you!

[Charlie]

Hi Sam,

Thanks for checking with us. 

Is this possible and is there a best way to do it?

Yes, it is totally possible. See (+) Up to 4x battery life: The benefits of assisted GPS in asset tracking - Blogs - Nordic Blog - Nordic DevZone (nordicsemi.com). The TTFF can be achieved within 60 seconds even without A-GPS on nRF9160DK, then the device can get GPS fix at a ten seconds interval.

1) Firstly, I could independently call a single GPS fix at every X seconds without having to worry about any intervals. 

2) I could use intervals, then restart the GPS every time that i want to change the interval. 

To maximise accuracy and minimise time to fix, what would be the recommended way to get variable rate fixes, or is there any other way i am not thinking about?  

I would say it does not matter too much if the GPS fix interval is the same, since the GPS operation time is the most power consuming part, but it is worth to keep monitoring the power consumption like the blog did during your development.

The optimization is a balance of your application needs, power consumption and accuracy. You may consider other location services using Wi-Fi and cellular.

(+) SSID-based Wi-Fi locationing: Comparing performance with other location services - Blogs - Nordic Blog - Nordic DevZone (nordicsemi.com)

Best regards,

Charlie