Playing with our new toy RTL2838

We have adquire this USB dongle RTL2838.

 What is RTL2838?

It's a high performance radio demodulator, that receive frequencies from 500 kHz up to 1.75 GHz. 

Most software for the RTL-SDR is also community developed, and provided free of charge. Note that RTL-SDRs cannot transmit.

Idea is to play and understand radio GSM standards. And fully understand with wireshark.

We will make use of the library GR-GSM.

GSM uses a digital modulation format called 0.3GMSK (Gaussian minimum shift keying). 

The 0.3 describes the bandwidth of the Gaussian filter with relation to the bit rate.

GMSK is a special type of digital FM modulation. 1's and 0's are represented by shifting the RF carrier by plus or minus 67.708KHz. 

In the next entry our plan is to learn GSM internal, and radio protocols.

Only for learning purposes: LTE sniffer, IMSI catcher, SMS decryption, etc. Note all information is available on the internet.