What is RTL-SDR?
RTL-SDR is a very cheap software defined radio that uses a DVB-T
TV tuner dongle based on the RTL2832U chipset. With the
combined efforts of Antti Palosaari, Eric Fry and Osmocom it was
found that the signal I/Q data could be accessed directly, which
allowed the DVB-T TV tuner to be converted into a wideband
software defined radio via a new software driver.
Essentially, this means that a cheap $20 TV tuner USB dongle with
the RTL2832U chip can be used as a computer based radio
scanner. This sort of scanner capability would have cost hundreds
or even thousands just a few years ago. The RTL-SDR is also often
referred to as RTL2832U, DVB-T SDR, or the “$20 Software Defined
Radio”.
There are many other software defined radios similar to the RTLSDR, but they all come at a much higher price. The FunCube PRO+
is a good receiver similar to the RTL-SDR, priced at around $190
USD. There is also the soon to be released HackRF (~$300USD) and
BladeRF SDRs ($420 and $650), which can both transmit and
receive.
http://www.rtl-sdr.com/about-rtl-sdr/
• What is Software Defined Radio?
• Radio components such as modulators,
demodulators and amplifiers are traditionally
implemented in hardware components. The
advent of modern computing allows these
traditionally hardware based components to be
implemented into software instead. Hence, the
software defined radio. This enables easy signal
processing and thus cheap wide band scanner
radios to be produced.
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What are some RTL-SDR Radio Scanner Applications?
The RTL-SDR can be used as a wide band radio scanner. Applications include
Listening to unencrypted Police/Ambulance/Fire/EMS conversations.
Listening to aircraft traffic control conversations.
Tracking aircraft positions like a radar with ADSB decoding.
Decoding aircraft ACARS short messages.
Scanning trunking radio conversations.
Decoding unencrypted digital voice transmissions.
Tracking maritime boat positions like a radar with AIS decoding.
Decoding POCSAG/FLEX pager traffic.
Scanning for cordless phones and baby monitors.
Tracking and receiving meteorological agency launched weather balloon data.
Tracking your own self launched high altitude balloon for payload recovery.
Receiving wireless temperature sensors and wireless power meter sensors.
Listening to VHF amateur radio.
Decoding ham radio APRS packets.
Watching analogue broadcast TV.
Sniffing GSM signals.
Using rtl-sdr on your Android device as a portable radio scanner.
Receiving GPS signals and decoding them.
Using rtl-sdr as a spectrum analyzer.
Receiving NOAA weather satellite images.
Listening to satellites and the ISS.
Radio astronomy.
Monitoring meteor scatter.
Listening to FM radio, and decoding RDS information.
Listening to DAB broadcast radio.
Use rtl-sdr as a panadapter for your traditional hardware radio.
Decoding taxi mobile data terminal signals.
Use rtl-sdr as a high quality entropy source for random number generation.
Use rtl-sdr as a noise figure indicator.
Reverse engineering unknown protocols.
Triangulating the source of a signal.
• Furthermore, with an upconverter or direct
sampling mod to receive HF signals the
applications are expanded to
• Listening to amateur radio hams on SSB with
LSB/USB modulation.
• Decoding digital amateur radio ham
communications such as CW/PSK/RTTY/SSTV.
• Receiving HF weatherfax.
• Receiving digital radio monodial shortwave radio
(DRM).
• Listening to international shortwave radio.
• Looking for RADAR signals like over the horizon
(OTH) radar, and HAARP signals.
• Note that not all the applications listed may be
legal in your country. Please be responsible.
• What is the RTL-SDR frequency range?
• This is dependant on the particular tuner variant
used in the dongle.
• TunerFrequency rangeElonics E400052 – 2200
MHz with a gap from 1100 MHz to 1250 MHz
(varies)Rafael Micro R820T24 – 1766
MHzFitipower FC001322 – 1100 MHzFitipower
FC001222 – 948.6 MHzFCI FC2580146 – 308 MHz
and 438 – 924 MHz (gap in between)Table
Source: Osmocom
• As you can see from the table, the Elonics
E4000 and Rafael Micro R820T dongles have the
greatest frequency range.
• General Purpose RTL-SDR Software
• We define general purpose SDR software as programs that allow
the RTL-SDR to work like a normal wideband radio receiver.
• SDR# (Windows/Linux with Mono) (Free)
• SDR#SDR# (pronounced “SDR Sharp”) is the most popular free RTLSDR compatible software in use at the moment. It is relatively
simple to use compared to other SDR software and has a simple set
up procedure. We have a full overview of the installation procedure
on our Quick Start Page.
• SDR# is a simple to use program that also has some advanced
features. It has a useful modular plugin type architecture, and many
plugins have already been developed by third party developers. The
basic SDR# download without any third party plugins includes a
standard FFT display and waterfall, a frequency manager, recording
plugin and a digital noise reduction plugin. SDR# also decodes RDS
signals from broadcast FM.