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Questions tagged [gsm]

GSM is an abbreviation for "Global System for Mobile Communication"

GSM is a second Generation Cellular Standard popularly known as 2G Standard. It is standardized by ETSI(European Telecommunications Standardization Institute).

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Is APN login information stored on SIM cards?

I am interfacing with a GSM modem module through the standard GSM AT command interface. Right now the access point names (APN), user names, and passwords for each known carrier are hard coded in my software. I am wondering if this information is…
FazJaxton
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How to Detect Non "GSM 7 bit alphabet" characters in input field

I am trying to detect if a text input field has any character that doesn't belong to the GSM 7 bit alphabet. The table with the characters is here http://www.dreamfabric.com/sms/default_alphabet.html After a lot of searching I found this (What…
George D.
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What is the maximum number of characters in an USSD message?

I've understood that an USSD message consists of 160 bytes. For 7 bit data coding schemes, the maximum number of characters is 160*8/7 which gives 182 characters. It's unclear to me what is the maximum number of characters for UCS2 encoding.…
Victor Ionescu
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Android: slow network during phone calls

We're working on an app that streams a large amount of data out via UDP for GSM-based phones. The idea is to use it while in conjunction with a voice call. If no voice call is present, things are good. However, if a voice call is active, it seems…
Matt Green
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Implementing a GSM Modem for SMS

So I've got a website that serves ~1000 users, coordinating scheduling for events. I'd like to enable our system to send SMS messages to users. I have access to the server and would like to purchase and install a GSM modem instead of subscribing to…
savinger
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USSD secure or not?

I have a question about USSD and security in this channel. As you know today mobile banking and many payments using USSD, I want to know is USSD safe? If USSD transactions using a5/1 for encryption,its totally broke few years a go and now can be…
jMoshayem
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error +HTTPACTION:0,601,0

I m trying to access a website using sim900 GSM module. This is the list of commands AT+CSQ +CSQ: 16,0 OK AT+HTTPINIT OK AT+HTTPPARA="CID",1 OK AT+HTTPPARA="URL","www.google.com" …
Syeda Amna Ahmed
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Writing a GSM modem driver?

I've been working on an application which uses a GSM modem for one of two things; check its status using the built in HTTP stack by sending a GET request to the server, or sending data to the server (using UDP). I have tried several different…
dantheman
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android: NeighboringCellInfo always empty !? why?

i'm trying to get info about the neighboring cells my phone can "see" atm. so far so good. i do this like this: telManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE); //... ArrayList…
xenonite
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Identify GSM encryption algorithm

I would like to find out whether my android phone (ADP) is using A5/0, A5/1 or A5/2 at a specific time. How can I achieve this?
Souly
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How to disable GSM connection in Android programmatically

I want to enable/disable an Android phone's GSM connection. I need to disable/enable calls and SMS as required. How might I do this?
Ram
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Voice call through GSM modem

I would like to use a GSM modem to make a voice call to a phone number, play a recorded message, wait for a digit to be pressed and then disconnect the call. The system needs to know if the line was busy, if the user answered and which digit was…
johndodo
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+CMS ERROR: 304, sending message using at command

Im new to GSM and AT command sets, based on the error +CMS ERROR: 304 its a Invalid PDU mode parameter according to activexperts Im trying to send message using AT command to GSM modem in PDU mode AT+CMGF=0 OK AT+CMGS=31 >…
kudarap
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Sending Unicode Messages (such as in Persian and Arabic) in C# using AT Commands through GSM Modem

I am developing an application for GSM Modems (D-Link DWM-156) in C#.Net using AT commands. I have a problem sending Unicode messages (Such as messages written in Persian or Arabic). Here it is the core of my program: SerialPort GSMPort = new…
Yasser Mohseni
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Custom encrypt GSM calls

Is it possible to catch voice audio stream with java (JME or Android), custom encrypt it and then send it as regular stream via regular GSM call? And off course decrypt cipher on other phone. Is application level java permitted to intercept audio…
ratko ratko
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