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SMS Receiver Project

From Scratchpad

The goal of this project was to build a receiver that could display all the sms messages sent from a gsm base station. The project started very ambitiously in 2002. I was a student then and had the time, but not the money to get the hardware I needed. Now I have some better hardware, but less time, so there hasn't been much progress lately.

[edit] My first setup

For the first setup I mostly used old parts that I had at home:

  • Nokia NHE-3 gsm phone
  • Jumptec 486 CPU and VGA card on a PC104 motherboard (bottom)
  • PC104 power supply card (center)
  • PC104 FPGA card (top)

The FPGA was connected to the ADC outputs on the Nokia baseband interface IC.

Phone and computer.
Connecting to the Nokia required some soldering.
The FPGA card also needed some modifications.


I got really nice data from the Nokia, and learned a lot about GSM, but I soon realized I would never be able to control its radio and timing to the extent that I could receive whatever I wanted. The service manual that I had did not provide enough information to control the ICs and since they were ASICs I could not get any datasheets.

IQ plot of the first frame I captured
Phase plot of the same frame


This is as far as I got, a MatLab script that found training sequences


[edit] The current setup

My current setup consists of:

  • ComBlock COM-3005 Cellular Band Receiver [1]
  • Xilinx Spartan 3 Starter Kit
  • Adlink PCI-7200 High Speed Digital IO card [[2]]

If I deside to do some more work on the project I think I will replace the Xilinx and Adlink boards with a ComBlock COM-1400 [3].