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GSM data quality - what does 16khz pulse duration mean?

I have a "Fixed Wireless Terminal model GW1000BL" which is a device that takes a SIM chip and supplies dial tone back to any RJ11 device plugged into it. I am trying to use this terminal as a means to communicate alarm signals from my home alarm to the central station. I can get low speed pulse signals (called 4+2 in alarm speak) to go through - but when I try a higher rate protocol called Contact ID - the transmission fails. I dont know if the issue is a frequency limitation in the cell system design (Rogers Canada GSM) or perhaps a setting on the Fixed Wireless Terminal that could be adjusted to improve the throughput.

The owners manual for the terminal talks of parameter settings that cen be changed - but they are all unfamiliar to me. The ones that seem like they might be of interest include:

ISD Call (Enable/Disable) Loop Interruption PR Outgoing Call (Enable/Disable)

16 khz Outgoing Call (Enable/Disable) 16khz Pulse Duration Dial Time Out 16khz default value 16khz table

Would anyone out there know if any of the above parameters might improve the data transmission rate for the terminal?

Thanks, Cindy

Reply to
cindyanello
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Looks like you and I have the same device (I presume this was an eBay purchase). I have a similar problem. I have a Rogers Pay-as-you-go SIM card installed in the unit, I can place and recieve calls. I am using the device to control a remote power controller that picks up after a few rings and utilizes touch-tone for control. I cannot reliably send touch tones from a landline to the GSM gateway.

The touch tones aren't making it very clearly to the device I have connected to the Fixed Wireless Terminal. I'm going to see what I can dig up to improve quality, if I find something I'll write back - if you find anything, please let me know.

The manual is absolutely terrible - I have no idea what some of the acronyms are - and I'm good with acronyms. Also - it sounds like the machine is British or something (the dial tone) - would be nice to change it to north american.

Best of luck

Reply to
shaun.rossi

Here's an observation. Wireless both TDMA and CDMA Radio encoding schemes don't handle sinusoids (what Touch Tones really are) very well. They all perform some sort (ACELP encoding is typical) of voice compression on the audio signal. It's pretty good for voice, enabling reasonable voice phoneme construction, but fails miserably for things like transmitting Touch Tones (or DTMF). To make a long story short, there's nothing much you can do.

snipped-for-privacy@hotmail.com wrote:

Reply to
Jack Adams

So when I call by voice mail, put in password, dial 1 for this, 2 for that and 3 for the other thing, I am not touch toning something ? It is all digital ?

TerryS

Reply to
Terry

Reply to
Jack Adams

Yes - thank you for that information, I wasn't being clear enough in my first post. I am aware that most cellular enabled devices re- generate the DTMF signalling at the remote end, as the touch tones are transfered out-of-voice band. I know a couple of cellular phones I've owned in the past had options on how to transmit the DTMF as voice traffic or as command traffic. That is what I was looking for on the box I own as it does *try* to do something, but it's not very good at it. I heard a perfect echo back of the touch tone I entered when monitoring on the handset. They are fixed length DTMF bursts, no matter how short or long my keystroke is. It's just not making it across properly I presume. I've tried Landline to GSM Gateway and GSM phone to GSM gateway - same results in both cases unfortunately. Yes, I think I'm stuck. Is anyone interested in my GSM gateway? It's really nice, but the touch tones are working for my application. I paid $200 US for it just recently, happy to get rid of it for $150 US. Everything is in perfect condition - otherwise I'll find another use some where for it.

Interestingly enough, when I call my office via the GSM gateway, the touch tones are properly signalling my PBX. I'm able to dial- extensions and access voicemail. The particular product I intended to use with the gateway, doesn't seem to handle it so well. It's a remote power switch that let's me control up to 8 AC electrical outlets.

-Shaun

Reply to
shaun.rossi

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