Intermittent Base-Rover Communication

Using two REACH RS units and the LORA radios to transmit corrections. I notice during Surveying that the corrections from the base seem to be intermittent. The grey bars go away and age of differential climbs up to about 12 - 15 seconds before they come back. This is when the base and rover are about 200 meters apart but there is not line of sight. The base is over the crest of a hill. I have the transmitter at full output 20 dB. Is this normal behavior?

Could be… Ground is killer. If you get somewhere where there are reflections, you may get intermittent reception. Sometimes, you can get bending of waves if the obstruction is far away from source or receiver. Best to get Base transceiver antenna as high as possible. (Base GPS Reach Antenna just needs good skyview.)

I live in Los Angeles County where a bluff is close to me. My TV is OK, but weak during the day with TV stations transmitting KWs. At dawn and dusk, all TV gets intermittent probably due to Atmospheric temperature inversion and/or microwave ducting.

Maybe the fresnel zone kicks in?

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Thanks for the reference.

I have my base on a 2 meter pole which at least gets it off the ground. My bench mark is behind a hill so I might establish another closer one at the job site and set the base up there. At least that way my base is less likely to get stolen - if I can see it!!:grinning:

Since I am surveying and stopping at each point to take data the age of differential issue does not seem to be affecting the process or results.

I know when doing PPK using CORS data the corrections can be at 30 second or longer time intervals.

Are you using the latest app version? We’ve added some LoRa-related fixes in v2.7.1.

Egor - Yes I am using the latest version v2.7.1.

What is your base configuration? Sending too much RTCM3 messages might still cause some problems. Other than that, it’s probably just a technology limitation.

Here it is - Base Configuration

Base Configuration

Rover Configuration

The messages are at the minimum, so it should be ok. I’ve just rolled out v2.7.2, which should also improve the communication, this time from RTKLIB side. You can check it out and see if the link got more stable.

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