This presentation will explore how you can survey the wireless world of the radio spectrum to get an idea of the signals around you, and decode transmissions that can be received by pointing an antenna towards satellites in space. Both are accomplished using Software Defined Radio and open source software, and emphasis is placed on the security (or lack thereof) in these communications systems. Using a drone, you can create your very own airborne RF surveying platform, so that you can fly your SDR payload through routes, and to altitudes, that you cannot normally access. Using open source tools and embedded hardware, you can gain greater visibility into the spatial deployment of different wireless protocols, and therefore where to mount an aerial RF attack, or fortify your defenses. Looking then beyond these terrestrial signals, with a decent satellite dish, it is possible to demodulate and decode signals sent down from geostationary ‘birds’ – often thought to be out of reach. The development of a GNU Radio-based INMARSAT Aero channel decoder will be shown, so you can read aircraft communications from space, and more. This will cover tips and techniques that can be employed to reverse engineer wireless signals in general.
A software engineer by training, Balint is a perpetual hacker, the Director of Vulnerability Research at Bastille Networks, and guy behind spench.net. His passion is Software Defined Radio and discovering all that can be decoded from the ether, as well as extracting interesting information from lesser-known data sources and visualising them in novel ways. When not receiving electromagnetic radiation, he likes to develop interactive web apps for presenting spatial data. Originally from Australia, he moved to the United States in 2012 to pursue his love of SDR as the Applications Specialist and SDR Evangelist at Ettus Research.
Jan 3, 2018 - With a simple radio such as an RTL-SDR and the right software, these. Inmarsat STD-C is an L-band geosynchronous satellite signal that.
RTL2832 Software Defined Radio Updated: Contents: Software defined radio (SDR) hardware is becoming smaller AND more capable. For many years, the king of small SDRs was the Softrock Radio. With a combination of surface mount and conventional discrete components, it offered high performance,small size, and low power consumption. Miniaturization took a large leap ahead in mid 2010 when the Funcube Dongle was introduced. It incorporated more functions onto a single chip than the Softrocks and hinted at the possibilities in a coming wave of. Eric Fry noticed, in early 2010 that certain DVB-T devices had special operating modes which could be exploited for reception modes other than digital television.
A year later, Antti Palosaari developed the concept of using a generic DVB-T receiver as an inexpensive general coverage VHF / UHF receiver. Thus was born the '$20 SDR.' It is an ante-upping game changer for entry-level and higly portable low power radios. This is a 'black swan' event that can change radio. Consider, for a moment, how the miniturization AND mass production of these small software defined radios can affect the activity of radio monitoring.
Imagine what people will do with cheap and easy access to just about any radio signal between about 24 and 1700 MHz? This includes public services - police, fire, air traffic control, military, maritime, certain satellite based services including navigation, communication, and so forth. Some signals in the preceeding list will be encrypted; others merely digitally encoded. Amateur radio, weather, and most maritime services will be in the clear.
With proper software, most of the signals received by these $20 SDRs can be demodulated / decoded / decrypted in real time. Other signals, protected by strong encryption, can be recorded and saved for future analysis. Don't laugh - there are people still analysing encrypted traffic from the second world war. DX listeners (and the NSA) can now record an entire band of RF spectrum and search for interesting signals at any later time. Before reading further, make note that the RTL-SDRs are not mere miniature versions of tabletop or rack mount radios of the past. These dongles, like their other SDR cousins, take radio into the age of full-up digital processing.
It is now possible to monitor an entire band and simultaneously decode EVERY signal that is a few decibels above the background noise! Better radios and software will push the limits until we are likewise pulling very very weak signals out of the noise as well.
The devices in question, for this breed of software defined radios, use a Realtek RTL2832 quadrature sampling detector in combination with a programmable oscillator (most commonly an Elonics E4000, Fitipower FC0013, FC0012, FC2580, and ). Experiments indicate that these devices perform fairly well without any hardware modification, and the software (drivers, firmware, and user interfaces) is sophisticated. It was initially possible to tune a desired frequency, sample a chunk of spectrum, and write the data to a file readable by a conventional SDR program.
For example, or would be used to read the file and demodulate signals in a 2 MHz wide band of recorded spectrum. Recent generations of RTL-SDR compatible software can directly access the data stream providing excellent real-time multimode reception. Newer R820 Tuner Architecture. The amateur radio community has worked fast on developing better software to operate the DVB-T radios and manipulate the resulting data.
As of late April 2012, software such as or can be used for reception of typical voice or digital modes plus esoteric things including encrypted voice. There are GNU Radio modules for, and downlinks.
Performance wise, the devices are pretty respectable. The specific tuning range available goes from about 60 MHZ to above 1700 MHZ using the best combination: an tuner.
Devices with the R820 tuner go down to 24 MHz. Other tuners have different ranges and compatibility with available software. Dynamic range is limited mostly by oscillator noise and the 8 bit A/D converter. These are not debilitating limits! Most users should find performance good enough for local stations and perhaps a bit of farther / weaker stations.
Basic amateur / public service / aircraft listening - even military satellite downlinks - should be easy on these little DVB-T radios. RTL-SDRs on HF Bands.
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