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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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What is meaning of negative dbm in signal strength?

When we try to get nearby cells and their LAC, MNC, signal (and while using other android apps) we are getting signal as negative value (like -85dbm). How should I take this? Should I ignore -ve sign and take absolute value or -85 is smaller…
Pranit Kothari
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Android: How do I get GSM signal strength for all available network operators

I am working on a little app to check the signal strength of various network operators in my area. My current operators signal is quite unstable and I want to look into the strength of other GSM operators. Sofar I've been using the TelephonyManager…
The Schwartz
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How to properly triangulate GSM cell towers to get a location?

First of all, I am trying to do all this disaster in c# (.net 4) so if you come up with some code to help me that would be appreciated but really anything would help at this point. I have a situation where I have a device that can only get GSM Cell…
kmp
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Answer incoming call using android.telecom and InCallService

Since API 21, Google has been adding features to android.telecom in general, especially by implementing more members of TelecomManager and the addition of InCallService. This last one is is supposed to allow non-system, 3rd-party apps to provide and…
leRobot
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How to send and receive some data via a GSM modem during an active call (Python and AT Command)

I wrote the below Python program to communicate with my D-Link DWM-156 GSM modem. This program wait for incoming calls and as it receive a RING alert, it accepts that call. Fortunately it works fine ;) The Program: import time import serial phone =…
Ebrahim Ghasemi
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How to access a SIM card programmatically?

Just any old GSM compatible SIM card (bonus for 3G USIM). I presume I need some hardware? Can anyone recommend something cheap for hobbyist, and something more professional? I presume that there will be full docs of an API with the h/w, so maybe…
Mawg says reinstate Monica
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Receiving "NO CARRIER" error while tring to make a call using GSM modem in Python

I want to make a call using my GSM modem. So I wrote the below program: import time import serial recipient = "+98xxxxxxxxxx" phone = serial.Serial("COM10", 115200, timeout=5) try: time.sleep(0.5) phone.write(b'ATZ\r') time.sleep(1) …
Ebrahim Ghasemi
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'Reliable' SMS Unicode & GSM Encoding in PHP

(Updated a little) I'm not very experienced with internationalization using PHP, it must be said, and a deal of searching didn't really provide the answers I was looking for. I'm in need of working out a reliable way to convert only 'relevant' text…
James B
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Get CellID, MCC, MNC, LAC, and Network in iOS 5.1

I need to retrieve CellID, MCC, MNC, LAC and Network (GSM, 3G) of the current Serving Cell Tower in iOS 5.1 (iPhone 4S). I know this information is available because I can see it in FieldTest Mode (accessible after calling ****3001#12345#****). I…
poorDeveloper
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Class 0 SMS (flash SMS) on Android

As I know that Nokia and some others phone (like iPhone) are able to sent and receive class 0 SMS , is it possible for android ? Do Android have the API? What is flash SMS? Flash SMS is an SMS which is displayed on the phone screen immediately upon…
xDragonZ
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Android as SIP to GSM gateway

Soon I could use a SIP to GSM gateway, because I'll need to make phone calls from Germany to a mobile phone in Czech Republik. Hence, I thought about implementing one. Now, the questions are: Does such a solution already exist (for a reasonable…
user346034
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AT+CMGS returns ERROR

I am using SIM900 GSM module connect to my AVR Microcontroller. I tested it with FT232 to see transmitting data. First Micro sends AT it will response OK AT OK AT+CMGF=1 OK AT+CMGS="+9893XXXXXX" returns ERROR and doesn't show ">" Could anybody…
Mohammad Farahi
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Detect when the outgoing call starts playing ringback tone

I'm trying to detect the state of an outgoing call when it starts playing ringback tone. I have tried various approaches for detecting this state. Here are some of them: 1. Using PhoneStateListener: (Cannot detect when outgoing call is answered in…
Shashank Agrawal
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WebSocket data consumption

I'm currently studying for a project involving a web-server and some raspberrys. The challenge would basically be to watch raspberry "status" on a web interface. Raspberrys are connected to the Internet through a GSM connection (mostly 3G). I'm…
Cyril CHAPON
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How to communicate App with Server without internet connection?

I want to know if there is any way to communicate users without internet connection to a server. I thought it might be possible through SMS and machine-readable encoding. However this question confirms that iOS apps allows sending but not reading…
lisovaccaro
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