Signal Processing Stack Exchange
Signal Processing Stack Exchange

Questions tagged [software-defined-radio]

207 questions
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What does correcting IQ do?

Some software (for example SDR Sharp) has a "Correct IQ" option. This is used to get rid of the DC spike in the middle of the display. What does this setting do to the signal? What is wrong with the IQ values that needs to be corrected?
Ken - Enough about Monica
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Are Software Defined Radios only Oscilloscopes?

I am wondering if SDRs (software defined radios), e.g. HackRF, RTL-SDR, or USRPs, are, in essence, just oscilloscopes you can plug to a computer to get the data from it. If not, what are the main differences between such devices ?
user35110
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Processing and plotting quadrature data in the frequency domain

Ok, so I recently started playing around with an SDR in an effort to challenge and educate myself. So, let's say the sampling rate (Fs) is 3MHz and of those we grab 3M samples. Now we are left with 3M samples consisting each of an IQ pair. Complex…
MacGruber
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Recommended device for testing my own SDR?

I'm trying to implement my own SDR using Matlab. I was wondering what kind of device I could buy in order to test it. I know I can use my own soundcard but I was thinking of EM waves, not sound. Is there a device capable of functioning as…
researcher9
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Generating I Q samlpes for particular sample rate

I want to know what the sample rate of I and Q samples generated for transmission, in the function below from https://github.com/lyusupov/ADSB-Out/blob/master/ADSB_Encoder.py samples are generated for transmission by a SDR (HackRF) so they are…
Mas
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G3RUH Multiplicative scrambler in C++

I have written and tested a G3RUH (1 + X^12 + X^17) descrambler. It seems to work quite well in an SDR project I'm working on. I'm currently working on a scrambler and I can't get it to work. Below is the test code I use. It has scrambling,…
Moses Browne Mwakyanjala
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Interference between two signals with the same frequency. (exercise from the book software receiver design)

I find it hard to describe the LPF. This is an exercise from the book Software Receiver Design Build Your Own Digital Communications System in Five Easy Steps chapter 4.23.
gcc17
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SDR lose samples at high bandwidth (sample rate)

When receiving bandwidth (sample rate) is small (<~28 MHz), the signals are received without any distortion. When I choose high bandwidth (for example 40 MHz), sometimes the signals become interrupted for a small amount of time and/or some noise is…
ALEX
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Can 2 (coherent) digitizers with input bandwith X be used to digitize a signal of banwidth 2X?

TL;DR: Can 2 tunable digitizers, each with an instantaneous bandwidth of X MHz and a common clock source, be used to achieve an instantaneous bandwidth of close to 2*X MHz by tuning their central frequencies and merging their output I+Q streams and…
Tomislav Nakic-Alfirevic
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Transmitting a 350 MHz signal

I'm currently on an SDR kick and reverse engineering and then emulating all of the remote controls in my house. There are numerous solutions to transmitting signals over 315 or 433 MHz and you can get super cheap boards available on Amazon to do…
slipvelocity
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In SDR could you isolate I and Q

I'm just curious if this could be a way of transmitting stereo?
Johanthan Edwards
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Simultaneous transmission of a D2D user

Can a D2D user (a device) transmit simultaneous different signals to a cellular user and a D2D receiver. If we suppose that the D2D device is equipped with SDR technology and can change their frequency channel while transmitting to a cellular user.…
user7341333
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Compare the quality of IQ data from different Software Defined Radios (SDRs)

I want to know what methods are best to scientifically evaluate the quality of different Software Defined Radios (SDRs) that spit out IQ samples. For this question, I would like to set the boundary conditions as follows: Their ADCs are from…
Denis
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Help in understanding the IQ raw file format used by SDRs/GnuRadio

I apologise as I feel like I should know this off the top of my head. I will try to explain what I believe I know and then ask a simple question. The usual file format used in software defined radios should be just numbers in binary format,…
Mara Ara
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RTL-SDR data types

I am using pyrtlsdr to read samples from an RTL-SDR. As in the example on the page, I am getting samples with sdr.read_samples(x). The RTL-SDR returns 16 bits per sample: 8 bits for I, 8 bits for Q. The result of the read_samples function is a…
Ken - Enough about Monica
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