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Showing posts with the label RTL-SDR

A word on Software Defined Radios (SDR)

Software Defined Radio (SDR ), resembles the techniques for creating software blocks of functional radio for reception/transmission. The concept extends from plain AM/ FM to Wi-Max/LTE radio transceivers and beyond. In other words, software defined radio (SDR) is defined as a radio in which the digitization is performed at some stage downstream from the antenna. Then the radio can use flexible and reconfigurable functional blocks for the implementation of digital signal processing algorithms. As technology advances, the digitization might be at, or very close to the antenna, such that almost all the radio functionalities are realized using software using high speed and reprogrammable digital signal processing engine             The old age radios had everything, from RF tuner to A/V detection in complete anlog domain with limited controls based on some varying resistance or impedance. The current radios consist of a mixture...

RTL-SDR as source with GNU Radio for WFM reception.

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Hi all... This is about using the poor man's SDR dongle ( RTL2832U ) with GNU Radio to receive Commercial FM stations ( Wideband FM stations)... Installation of GNU Radio was a breeze in Ubuntu 12.04 using the build script by Marcus Leech.. thank to him... My core 2 duo machine took 2 hours to build the whole thing... :) Being a total noob in the complex base-band world, i decided to try something for getting familiarized with GNU Radio.. Opened gnuradio-companion.. Tried out some examples. Most of them were based on USRP  SDR Transceiver. But the source block listed the support of RT2832U to be used as a source.. thanks to osmocom . So now i decided to create a WFM receiver in GNU Radio with IQ signals collecting from poor man's receiver. Hooked the SDR dongle.. checked with some similar implementations over internet.. Created a LPF, WFM receive block, GUI Waterfall Sink block, Audio Sink block. Spend a considerable amount of time in understanding all parameters ...

RTL-SDR with Raspberry Pi 'PiFm' project

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Hi all...        I was totally excited after receiving the RTL-SDR dongle, the poor man's Software Defined Radio Receiver. I hooked it up to see the beautiful spectrum of signals in SDR# software.   And it worked like awesome. The blue waterfall is just awesome.... I wanted to test the device as fast as i could...But since i live in a villlage with no Commercial FM coverage, it semed to difficult to get hold to any strong RF signals.. Still i could get some random energies in 945-960 Mhz GSM band...pretty noisy... digital data.. so not much to be heard to... After some random browsing, i came across a beautiful project to make the Rasp Pi transmit in Wide Band FM mode. The project name is PiFm . It is a nice simple example of SDR transmitter. So without any hardware for FM modulation, a 300 lines C code modulates the DPLL output of Pi's ARM Processor with respect to the digital music data from a wave file. "Kudos to the guys who did it..". The output com...