Tagged: mobile

Video showing SMS Texts and Voice Calls being sniffed with an RTL-SDR

Over on YouTube user Osama SH has uploaded a video briefly showing the steps needed to use an RTL-SDR dongle to sniff some SMS text messages and voice calls made from his own phone. This can be done if some encryption data is known about the phone sending the messages, so it cannot be used to listen in on any phone – just ones you have access to. In the video he uses Airprobe and Wireshark to initially sniff the data, and find the information needed to decode the text message. Once through the process he is able to recover the SMS message and some voice audio files.

Sniffing and Analyzing GSM Signals with GR-GSM

Over a year ago we wrote a tutorial on how to analyze GSM cellular phone signals using a RTL-SDR, a Linux computer with GNU Radio, Wireshark and a GSM decoder called Airprobe. With this combination it is possible to easily decode GSM system messages. Setting up Airprobe is can be difficult as it is unmaintained and incompatible with the new version of GNU Radio without patches.

Now a new software package called gr-gsm has been released on GitHub which seems to be a newer and improved version of Airprobe. The gr-gsm software is also much easier to install, uses the newer GNU Radio 3.7 and seems to decode the system data with much less trouble than Airprobe did. We will soon update our tutorial to use gr-gsm, but the instructions on the GitHub are already quite good. The author of gr-gsm also appears to be actively adding new features to the software as well. The video below shows gr-gsm in action.

SDR Touch Updated to Version 2.0

SDR Touch, the popular Android based software defined radio software for the RTL-SDR has been updated to version 2.0. This new version is a complete rewrite with many optimizations listed below.

  • 100% rewritten from scratch
  • Improved reception sensitivity and quality
  • Optimized engine
  • GUI overhaul (Landscape mode, more flexible)
  • 16 bit audio
  • FIR filtering

The author also writes that the rewrite allows for new features coming out in the future such as adjustable bandwidth, FFT size, plugins and a separate GUI for in-car use. SDR Touch is available from the Android Play store.

SDR Touch Android GUI for RTL-SDR
SDR Touch Android GUI for RTL-SDR

XiOne – A RTL2832U based Portable Software Defined Radio: Indigogo Funding Campaign

A new funding campaign for an RTL2832U based software defined radio has gone up on Indiegogo. The new SDR is called the XiOne and is intended to be the first SDR that is easy to use with smartphones and open to the maker community.

With its 100 kHz to 1.7 GHz receiving range, the XiOne has a similar tuning range to the standard RTL-SDR dongles when an upconverter or the direct sampling mod is used. What makes the XiOne different is that it will have a built in MIPS processor, an internal rechargeable battery for portability and it will connect directly through WiFi to a smart device. They are also developing SDR GUI software for mobile devices including decoders for things like ADS-B, AIS and NOAA Satellites.

The IndieGoGo backer price for a XiOne is $179 USD, but if you act fast there are 100 units available at the promotional price of $139 USD. At the moment they have a working prototype with completed firmware, portable Java based SDR GUI, iPhone demodulation software, a MacOS ADS-B receiver, an iPad AIS receiver and an iPad spectrum analyzer. The fundraiser is to help them begin serial production.

There is a Reddit thread discussing the project here.

XiOne Prototype Internals
XiOne Prototype Internals
XiOne Casing
XiOne Casing

Analyzing TD-LTE with the RTL-SDR

TD-LTE is a mobile phone standard acronym for Time Division Long Term Evolution. It is one of two variants of LTE technology, with the other being FD-LTE (Frequency Division LTE).

Over in China where TD-LTE is commonly used, Jiao Xianjun discovered that the current LTE-Cell-Scanner Linux program did not support TD-LTE, so he made a fork which does support TD-LTE. LTE-Cell-Scanner is a program which can decode LTE cell tower data which contains information like the cell ID, transmit frequency and transmit strength. With his modified LTE-Cell-Scanner, some MATLAB scripts he wrote and an RTL-SDR, Jiao was able to decode the cell information from 10 TD-LTE signals and 2 FD-LTE signals. He has uploaded a video showing this too.

ADS-B Decoder for the RTL-SDR now available for Android

A (beta version) of an ADS-B decoder and display app for the RTL-SDR dongle for Android has been released. This app allows you to receive the ADS-B radio signals emitted by modern aircraft, which contain information such as flight number, latitude, longitude and altitude, essentially giving you a live portable aircraft radar.

To use the app, you will need an Android device that supports USB OTG, which most Android devices on Android 4.0+ should support. You will also need a USB OTG cable, and an RTL-SDR dongle. You may want to consider a USB OTG cable that has a second port for external charging capabilities, as the RTL-SDR can drain the battery quickly.

The app is cheaply priced at under $2, so give it a try!

ADS-B Decoding on Android
ADS-B Decoding on Android

SDRTouch Version 1.7 Released

The Android based SDR program SDRTouch has been officially updated to version 1.7. News comes via this forum post. This looks to be a major update which significantly improves audio quality and performance. The new features are listed below.

  • FM is now in STEREO
  • New audio recording feature for PRO users
  • Improved reception and audio quality. All filters were tested for quality and all bugs discovered were removed.
  • The multi-threading logic was completely rewritten. Now it’s faster than ever before.
  • Audio is now using NDK.
  • PPM correction, audio gain setting
  • A lot of bug fixes and UI enhancements
  • Experimental x86 support
SDR Touch Screenshot

Receiving, Decoding and Decrypting GSM with the RTL-SDR : YouTube Talk and Slides

A few days ago we posted about how Domi aka Domonkos Tomcsányi wrote on his blog about decoding and decrypting GSM signals from your own cell phones. Domi also did a talk at the CampZero conference which has now been uploaded to YouTube. His slides can be obtained from this link.