L70 positioning error at standstill

IoT Modules GNSS Module
1

We have a problem with the L70 where we frequently experience large errors in the positioning when the unit is at a standstill. The position can wander away as far as 50-100 meters under clear sky with no nearby obstructions and with an external antenna. It usually starts a few minutes after stopping and it works fine while moving at speed. We have thoroughly checked and ruled out RF related issues. Right now we would like to make sure that the unit does not end up in some kind of power save mode by itself and also that we are running the latest firmware.

Questions:

  1. What is the latest firmware version for the L70?
  2. Is it possible that the module does not run in normal mode when started with default settings?
  3. Is there a a command to query the module for what mode it is in?

Thanks

2

Hi pfn,

When started with default settings, the module runs on a Full On mode.

The latest firmware version is L70BGR03A05S . Query f/w version via command: $PQVERNO,R*3F
If you need this latest f/w, please leave a comment.

Could you please check GSV message, <SatCN0 field? If the rough average CN0 is below 35 dB-Hz, that means the satellites signal is not strong enough. Please check the extra antenna parameter shown below. Or you can send an L70 testing log to me via MESSAGE for analysis.

Best regards.
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3

Thank you. There is no response on the $PQVERNO,R3F command. The '$PMTK60531’ command works however. I guess that means it is old? Is it possible to upgrade?

The SNR value is generally Ok (approx 40-45) and higher when the problem occurs than while driving. I will send you a log.

Thanks

4

Hi pfn,

The latest f/w and upgrading tool are sent via message.

Best regards.

5

Hi,

Did you get the messages I sent?

Best regards

6

Hi pfn,

I’ sorry I didn’t get any message from you. Maybe you can reply to the message about f/w upgrade that I sent to you.

Best regards.

7

HI,

I have replied to the message twice. I will do it once again but if it does not work maybe you could provide an alternative address?

Thanks

8

Hi pfn,

I’m sorry about the delay. Please contact with me via e-mail.
raphael.wu@quectel.com

Best regards.

9

I have sent the messages again. Please check your spam filter if you do not receive them.

Thanks

10

Hi pfn,

I have check your NMEA log. RMC always report tiny speed. The satellites signal are okay, so it might be the static navigation speed caused this problem.

To set a static speed threshold via PMTK386 command. After setting a threshold, RMC will not report a speed at static state.

If you have more problems about location, please send NMEA logs through e-mail.

Best regards.

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11

Static navigation only delays the problem and has side effects. I have sent you a separate email.

Best regards.

12

Hi pfn,

I’m sorry that our testing team didn’t reappear the static drifting situation. Even in a weaker signal environment, the L70 drifting can not reach a 70m record.

Please check 1) if there is some interference which affect the antenna?
2) Is this situation an isolated phenomenon?
3) You can contact with a local FAE to help you on testing.

Best regards.