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Wireless Networking Hardware Technology

Wired Voice and Data to Cellular Options? 33

Posted by Cliff from the landlines-haven't-died-yet dept.
otterboy asks: "I am involved with a remote scuba diving operation in Northern British Columbia. The lodge has a regular wired handset, with a wire running up to the top of a nearby mountain. At the top of the mountain sits a little shack, which contains a cell phone, a big antenna, and a black box from Motorola. That box provides an RJ11 jack into which we can plug the 'regular' phone, which allows us to use the cell link from the regular wired phone in the lodge, since the only cell signal we can get is at the top of this mountain. We also use a GSM modem (over the 'regular' phone line, which gets converted to a cell signal up on the mountain), but the best rate we can get is about 4.8kbs. According to Motorola, this is a limitation of their converter. I've looked at Cellsocket, but it deals only with voice. Does anyone know of a converter with better data performance, or are we stuck with Motorola?"
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Wired Voice and Data to Cellular Options? More

Wired Voice and Data to Cellular Options?

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  • No questions asked. You use their network, you use their hardware and suck up all the problems with it.

    I know, it's not nice.

  • I've seen GSM modems, plug one into a dirt cheap laptop (ebay), then use 802.11 and a good antenna to get the signal down. Means you have two phone lines, but it is an option.

    The other thing that comes to mind is starband is two-way satalite, which might fit your needs better.

    There are other converters, or have been from time to time. I suspect all have a similear limit. Each time you do a digital-analog conversion you lose something, and if you think about it, you are adding anouther digital-analog s

    • Why bother with 802.11b? There's already existing phone wire from the mountain to the lodge; just run some cat5 cable alongside. Since GSM is slow anyway, 10 megabits would be plenty and thus the maximum distance would be something around 300 meters -- not too bad. If that's not enough, add some repeters and power them with Power over Ethernet -- the cost is still likely to be less than two 802.11b cards and two good directional antennae.

      Besides, you don't want to be victimized by remote North British

      • Every hear of ground loops? Ever hear of other EE terms? Twisted pair wires are not for use between buildings. You deserve to fry your comptuers if you are stupid enough to try this. Odds are you will one day too. (Note, old 10base5 systems are the only copper based system I know of designed to run between buildings).

        I'll bet that their phone line to the shack isn't properly protected from ground problems and lightening strikes.

        • Every hear of ground loops? Ever hear of other EE terms? Twisted pair wires are not for use between buildings. You deserve to fry your comptuers if you are stupid enough to try this. Odds are you will one day too. (Note, old 10base5 systems are the only copper based system I know of designed to run between buildings).

          Okay, so maybe not cat5 (although they do make group loop isolators for them). Fiber would work too, and would span longer distances.

  • Fixed Subscriber Unit (Score:3, Informative)

    by cyan ( 370 ) on Wednesday October 22, 2003 @11:25PM (#7287440) Homepage Journal
    The unit that the article author is speaking of is known as a "Fixed Subscriber Unit", which is rapidly becoming the choice method to replace the old Autotel and Mobitel systems. If you think it's bad now, just imagine what it was like trying to get *any* data at all over the old method of doing things. These new FSU's are quite an improvement over what was used in the past. No, Motorola isn't the only company which manufacturs FSU's, however, they are among the best. Furthermore, any other FSU by any other company will yield around the same (if not worse) results.

    Your only other alternative would be to build your own network out there (either by a microwave or 802.11 longshot, or by running some of your own copper over the distance from the nearest telephone CO.) Sattelite Internet service may also be an option, although possibly expensive. At least with a FSU your only initial cost is in the capital expense, the recurring expense is just as if you had a regular cellular telephone (i.e. inexpensive.)

    Speeds can't get much better over a cellular network because of all the latency involved. Just be thankful that you've got a CDMA FSU as opposed to one that uses the old-school analog AMPS. The signal's gotta go up to the shack, over the air (a great distance by the sound of it), into the cell tower, then trunk it all the way back to your ISP, where the signal gets converted. That's a lot of delay, not withstanding the sound quality factors, you're not going to get much better.

    Naturally, I'm speaking of carrying an actual modem carrier over CDMA (as opposed to something like 1x, which is raw data.) Personally, I'd try to get some 802.11 longshot going, perhaps with the co-operation of your local amateur radio group, especially since you have the facilities atop the mountain already.

    • Sattelite Internet service may also be an option, although possibly expensive.

      Slightly off-topic, but a question about satellite internet...

      Imagine you were in a not-so-rich country within, say, 1500 miles of the continental US, in which high speed internet access outside of the capital city is VERY expensive.

      Among the few options available there is Hughes Direcway [direcway.com], except at about 15 times the going price in the USA.

      Assuming the availability of expert personnel to mount the dish, is there anythin

      • Assuming the availability of expert personnel to mount the dish, is there anything stopping someone from subscribing in the USA and then bringing the dish there? The cost of the flight would be covered in about 2 months' service fees.

        Assuming you could still see the same satellite, there's probably no technical reason (although I'm sure it's prohibited both by contract and maybe even encryption export laws). If you can't see the same satellites, then it wouldn't work.

        • Assuming you could still see the same satellite, there's probably no technical reason (although I'm sure it's prohibited both by contract and maybe even encryption export laws). If you can't see the same satellites, then it wouldn't work.

          Does anyone know the footprint of the satellite you'd be assigned to if you were to subscribe in, for instance, Brownsville, TX? On the web site they say you need a view of the southern sky. Would that same satellite be visible from Nicaragua? That's less far south fro

  • Most provides seem to provide access to 3g systems...I dont know about in CA but here in the US you can get unlimited data from tmobile for around $20 a month. Buy their pc card or a phone with a data jack and plug it into a computer. network card on the computer to network card where you are....crossover cable or a switch on your end and BOOM you have faster internet.

    I know AT&T has similar plans and verizon (but verizon sucks)

    • I'd really love to know, because I'm planning on signing up for their unlimited data service sometime next year, and dropping my home internet connection.

      And, no, I'm not switching from Verizion, because they have been the most reliable carrier I've ever used for the locations I travel, and I've never had a billing problem with them. :-)
      • I dont know why you would want to drop your home internet...I dont think celular would be quite as fast or as reliable.

        As for verizon (in the minneapolis area), they are by far the worst of the large providors. Everyone that I know with service from them is dissatisfied with almost every aspect (except the billing, never messed up billing). Even the phones they provide have problems on their network here, resulting in bad battery life...and wtf is with their new phones from LG, I have never heard of th

  • I worked for a company in Utah that was running all of their radio broadcasts via digital signals up to the tops of mountains (much, much better transmit range). Since we were in the valley, one of our hops went from the middle of the city, off of the top of the opposite mountains, to a Gas station that had line-of-site to the top of the peak. The Gas station didn't take much to convince them into letting us stick a few medium sized yagis on the roof. BTW, none of this was 802.11b, it was all run through th
  • Erricson F221M [ericsson.com]. I've used it before and it works well (for voice). I've used it for data, but that requires a serial cable (it acts like a modem). I would think about setting up a remote server or something. In my experience, Powertec [powertec.com.au] has always been friendly and helpful. I live in the US and they have helped a few times with similar projects - they understand North American cell networks, etc.
  • I deployed a wireless email/voice/data solution much like this (for drilling rigs here in California) using hardware from Telular [telular.com] and GSM/GPRS service from T-Mobile. Telular was great to work for, and their hardware (and support) is top-notch. I wholeheartedly recommend them.
    • I said "work for" without meaning those exact words-- you'll have to pardon me, I was on campus all day and I'm quite tired. I meant "work with".. I was employed as a consultant for a drilling company to implement a wireless data solution, and we ended up using Telular and T-Mobile.
  • I'm talking out of my ass here, but if you could directly connect a serial link to a cell phone you would get better throughput. I can get 9.6Kbps from Fido. You would need to get some sort of serial link extender from the mountain to your terminal.

    By the way, what's the closest city? Are you north of Prince Rupert?
  • The problems may extend further than just the converter. It may also be a weak signal, and it could be compounded by the run of cable between the two buildings.

    The phone should have a data connection available as well - you might try hooking that up and running an rs-232 cable using the phone's internal modem.

    But a cell phone is typically only going to give you 14.4kbps max, unless you have high speed access through one of many providers. It's a 3x speed increase, but read on...

    Beyond that, I'd g
  • ...but I gotta say, that's one damn cool setup you've described. Kinda curious why you don't do line-of-sight radio to the top of the mountain, though. Running the wire must have cost a bundle.
    • ...but I gotta say, that's one damn cool setup you've described. Kinda curious why you don't do line-of-sight radio to the top of the mountain, though. Running the wire must have cost a bundle.

      Maybe they needed to run it anyway to get power up there, so people didn't have to climb the mountain in the snow to change batteries all the time.

      • Most (all?) of the towers around my area are now solar-cell powered, with the exception of some really big telco microwave towers, which have a diesel generator (mostly because the equipment needs to be air-conditioned).
        • Wait, I lie. There are a few towers with power lines running to them. My bad.
        • Most (all?) of the towers around my area are now solar-cell powered, with the exception of some really big telco microwave towers, which have a diesel generator (mostly because the equipment needs to be air-conditioned).

          I don't know much about this since I consider snow to be the worst sort of poison (i.e., the cold kind) but it seems as if in heavy-snow mountainous areas there might be a problem with buildup on the solar panel in the winter months.

  • if you're using GSM, then ask if your provider can give you GPRS. it's a bodge technology, but gives roughly 56k modem speeds.
  • lots of these answers are already given, but I think this is a good consolidation of the issues:

    It sounds like you have 2 problems -

    1. the cellular network... the 4800 limitter thing usually is for an analog phone. Since you're talking about being in a remote area, I wouldn't be surprised if the only signal you're able to get is analog. If that's the case, then 4800 is about the best you can hope to get out of it, and you don't need to worry about problem #2. ( here [canyonriver.com] is the black box I suspect you're

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