Lefebure Design - Configuring a NovAtel RTK Rover

How to configure a NovAtel GNSS receiver as a RTK rover.

[mxa]

@deagsy The Smart-AG is a L1-only receiver. It can do RTK, but only on extremely short baselines. Radios are usually preferred when you have a short baseline as there is no monthly fee.

The MR10 can be paired with an external radio, computer with USB cellular modem, an Intuicom RTK-Bridge, a cell phone with NTRIP client, or a hand full of other options.

[mxa]

@deagsy The MR15 has a cellular modem built in with NTRIP software. When powered on, it will automatically connect to the Internet and start streaming RTK correction data. No switches to turn on or buttons to push, it just gets correction data whenever it has power. The MR15 is offered with 3 different modems, two of which are for the North America market. One is CDMA for Verizon, the other is GSM and will work with a sim card from any GSM carrier (AT&T or T-Mobile).

[mxa]

@deagsy The NovAtel receivers will hold RTK fix for 60 seconds after correction data last comes in, but accuracy will degrade as the data ages. 10-20 seconds is quite acceptable. Normally you'll see 2-8 seconds of age when moving data over the cellular networks, but you may occasionally see correction ages over that if the network is saturated with other data traffic.

[mxa]

@deagsy The amount of data moved will depend on what format the correction data is in. RTCM v3 is approximately twice the size of CMR+ data. In either case, it is still a relatively tiny amount of data.

The closer your rover is to the base station, the more accurate the position data will be. The geographic location of the Caster is irrelevant because the data is traveling over the Internet.

[mxa]

@deagsy My Android NTRIP client can be used in place of a full windows computer. It connects to the GNSS receiver via Bluetooth SPP. Both the MR10 and MR15 have integrated Bluetooth modules, which is the platform I tested against during development.

[deagsy]

So I understand... the MR15 does all this without the need of a computer/phone? I see it supports a good range of gsm/3g bands.

In the field you would use the MR10 + 3G dongle and then feed it into your own GPS software on the computer or plug COM1 into a GPS system? This could also be done using the cheaper Smart-AG?

Your android app would remove the need of a computer?

NTRIP only uses about 4 meg an hour? does this vary on the service? How close should the caster be? What's the max latency?