GNSS signal processing functions written in C
       Code generations
       Signal acquisition / tracking
       Decoding navigation messages
       Pseudo-range / carrier phase mesurements
   GUI application (AP) written in C++/CLI
   Visualization of GNSS signal processing in real-time
   Real-time positioning with RTKLIB (http://www.rtklib.com/)
   Observation data can be outputted in RINEX or RTCM format
   Support following signals (tracking and decoding navigation message)
       GPS L1CA
       GLONASS G1
       Galileo E1B
       BeiDou B1I
       QZSS L1CA/SAIF/LEX
       SBAS L1
   Support following front-ends for real-time positioning
       NSL Stereo http://www.nsl.eu.com/primo.html
       SiGe GN3S sampler v2/v3 https://www.sparkfun.com/products/10981
       Nuand BladeRF http://nuand.com/
       RTL-SDR http://sdr.osmocom.org/trac/wiki/rtl-sdr
   Support RF binary file for post processing

Mentioned on https://www.rtl-sdr.com/receiving-gps-with-an-rtl-sdr-dongle-and-gps-antenna/

Rtl_power is a unix-hacker's approach to the waterfall. Its unique features include:
- Unlimited frequency range. You can do the whole 1.7GHz of a dongle.
- Unlimited time. At least until you run out of disk for logging.
- Unlimited FFT bins. But in practice I don't think I've taken it above 100k bins.
- Quantitative rendering. Exact power levels are logged.
- Runs on anything. A slower computer will use less samples to keep up.

The blog has a lot of other interesting articles, e.g. http://kmkeen.com/tiny-code/, http://kmkeen.com/flash-recovery/ , http://kmkeen.com/fp/ just to name a few.

SDR receivers and transmitters for Red Pitaya.

CubicSDR is a cross-platform Software-Defined Radio application which allows you to navigate the radio spectrum and demodulate any signals you might discover.  It currently includes several common analog demodulation schemes such as AM and FM and will support digital modes in the future.  Many digital decoding applications are available now that can use the analog outputs to process digital signals by “piping” the data from CubicSDR to another program using software like Soundflower, Jack Audio or VBCable.

Currently CubicSDR supports the RTL-SDR which is an inexpensive SDR device that can be purchased online for about $10 and up.   Search for “RTL2832U” and “820T” or “820T2” on sites such as eBay or Amazon to see what’s available.   Support for more advanced and higher bandwidth devices will be added in the future.

Passive radar using FM broadcast transmitters and a dual channel SDR receiver.

V3 SNOWLeo SDR is a low-cost open source software defined radio platform based on Xilinx ZYNQ SoC and MYRIAD RF module. It include Giga Ethernet, USB OTG, HDMI, SDIO and USB-UART. SNOWLeo SDR is equipped an MYRIAD module that support 300MHz~3.8GHz, 28MHz BW application, such as WiFi, LTE or WiMax.

List of up-converters to allow HF reception with RTLSDR receivers.

The firmware for airspy will be released once it is cleaned up.

Collection of articles about software defined radio.