I have been a subscriber to a VRS for a couple of years. But, not everywhere I work has VRS coverage. And some areas have VRS but poor cellular. So, a couple of questions. I believe I asked some of these before, but didn't get real good answers, and I know technology has developed since then.
1) Intuicom RTK bridge: I am thinking of getting one of these to help where cell service is spotty. Set it up where service is good and rebroadcast on UHF to the rover. Any comments from users? How well does it work? Any problems?
2) I want to setup my base, but rather than use a radio link I want to use a cell link to extend the radius of coverage. What equipment is out there for the base end? I guess what I want is to treat the cell network as a "radio link", almost like having an old style phone modem at each end. I use Trimble if it matters.
3) My Trimble R8's have internal radios. I know there is an option to have a cell modem on board instead of the radio. Does this do what I want in #2 above?
Years ago I went to occupy an airport HARN station and someone had a base unit there with a cell phone tethered to it. I believe the GPS was Leica if I recall correctly. But that was in the days when data over cell was CDMA with fixed IP addresses, or just dial up from one phone to another.
Thanks much, Gavin. I will wait to see what you can provide.
The roll-your-own caster sounds good. I think that means that i would setup the caster on a PC in my office. The base, wherever it is, would send data there via cell. The rover would then connect to the caster via cell and get the corrections. Only problem is that base would always be sending, not sure how much data that would use up in a day.
To me the ideal would be to be able to connect on demand to the base from the rover, and stream corrections as long as the connection is up. Our application typically would be to get RTK at scattered points, say a few 5 minute periods per hour, so a constant connection would not be required.
I did a google on circuit switched, and Verizon has stopped selling that, and will discontinue it altogether in 2014.
I remember looking at raven modems for this, not sure if they would still work now that most carriers have gone to 3G or 4G.
I have been doing #2 for around 10 years, I use CSD, and yes that is getting rare, so my days of doing that may be about up. I use T-Mobile as a carrier and Leica gear. I haven't tried it in a while because I have either been doing PP static or using a RTN or not in an area with cell coverage, maybe I will give it a try next time I am out (and in an area with cell coverage) and see if it still works.
I am real interested in your #1 question too, in fact I am looking at moving solely to Intuicom for my radio / bridge solution and ditching VHF all together.
SHG
I didn't mean to monopolize that airport HARN station years ago. 😀
Yes, it was phone-to-phone dial up with a Leica 1200. VRS didn't exist, and the cell phone range was way beyond the radios of the time so some early users got into trouble and fell off the "edge" of their transformations. I remember that Ellis Veatch did some of the early "science fair" experiments over wide areas in Colorado with cell phone GPS which he published on his website, now long gone.
None of that, unfortunately, is of any use in answering your questions, and I haven't been in the field with RTK for years. But your post brought back some memories.
Thanks
I have been researching doing about the same thing. I have spoke with a guy that has done it.
Its appears a simple way to do it would be a Mifi connected small PC running a NTRIP client feeding the corrections to a base radio (no base receiver). It doesn't take much of a PC but one with a serial port to connect to the radio makes it all simpler. You also need the right cable, PC to base radio. There is at least one free NTRIP client available.
RTK over cellular- How to's
Gavin: thanks again for all the great info. I will try some of these ideas.
RTK over cellular- How to's
Yeah, thanks Gavin!:-D That was some great information...
I hope you are going to the conference; I'd like to pick your brain, if I could....:clap:
RTK over cellular- How to's
> ..... Looking for a bit of test data on the new NAD83-2011 from your neck of the woods...
I'd be glad to help....
I'll give you a call when I get back.
Doug
RTK over cellular- How to's
OK, maybe I am just dense, really no doubt about it actually!
I downloaded the free client, now what?
Here is what I would like to do using Leica 1200's that have a modem capable of receiving RTN corrections via NTRIP (both base and rover are already outfitted with the modem).
Set up a base on my project.
Have the NTRIP client running at my office.
Connect the base to the NTRIP client at my office over the modem.
Connect to the NTRIP client with my rover over a modem (this part should be the same as connecting to a RTN which I already can do).
So, both the base and rover are remote from the client running at my office.
The free client looks like it wants to connect direct with a serial port, is that correct? Is there a way to do the connection over an IP address via modem from the remote base?
I need to be spoon fed in a little more detail as to how this would work.
SHG
RTK over cellular- How to's
Run the NTRIP client to start. Click the edit fields and fill in the right info. Then click Connect.
RTK over cellular- How to's
Thanks Gavin and Leon, yes, I might of used the wrong terms, Gavin, you have outlined what I want to do, I need to play with this a bit and see if I can make it work!
SHG
Hijack SHG
That is my survey truck. A 2001 Dodge 2500 with a custom built bed, truck now with 252K miles.
SHG
Hi..how exactly did that work(phone to phone dial up)..trying to configure such for a leica 1200 right now..with a couple of gsm gfus..
Thats closest we have to an rtk capable gps right now i'm afraid..any point in d right direction would b appreciated
Gage,
I have successfully used GSM as the RTK link between 1200's in a single base scenario.?ÿ The firs step is to acquire a static IP for at least the base, AT&T's system requires both receivers to have static for some reason though.?ÿ Once you have that, you just set the base to broadcast via the GSM radio.?ÿ On the rover end you set up a new network utilizing the static IP of the base/reference.?ÿ You can refer to the 1200 technical reference for more detail.?ÿ It has been a while since I have used the 1200's but it did work well.?ÿ Good luck and welcome to the form.
