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Questions tagged [modulation]

Anything related to *signal modulation*, i.e. the process of encoding the information provided by some source into the variations of some property (e.g. amplitude, frequency, phase, polarization, etc.) of a carrier signal suitable to be transmitted over a communication channel.

Anything related to signal modulation, i.e. the process of encoding the information provided by some source into the variations of some property (e.g. amplitude, frequency, phase, polarization, etc.) of a carrier signal suitable to be transmitted over a communication channel.

See Wikipedia page on signal modulation.

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QPSK simulation with AWGN and BER/SER

I have a matlab code of QPSK simulation over baseband with AWGN noise, I'm calculating BER over each SNR value and plotting it along with Theoretical BER. When I'm generating SNR values in dB from 1 to 20 the code only computes simulated BER values…
Daniel Cohen
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Calculate Frequency Modulation in Python

I'm trying to calculate Frequency Modulation (radio context) for a given audio file (12 seconds), I managed to do it on a sine wave with the following formula: fm = np.sin(TWO_PI * (fc + b * data) * t) Where fc is the Carrier Frequency, b is the…
yarin Cohen
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Calculate Amplitude Modulation in Python

I have a 4 seconds audio sample of someone saying "hello", I managed to load the wav file and show it in a time-amplitude spectrum, my next step was to calculate a AM (Amplitude Modulation) on this sound, I managed to do it on a sine wave I created…
yarin Cohen
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How to modify a particular frequency in a sound file in p5.js?

So basically i am making audio equaliser in p5.js and i dont know how to modulate a particular freq. in a soundFile if anyone know please provide some insight to it.
Aniket Verma
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Generating FSK Modulated signals in GnuRadio

I am trying to recreate the signal from the RC car toy and control it with HackRf and GNU-Radio. I have identified following: Controller operates on 2.463 GHz The bandwidth is 1MHz Logical "1" 2.4635 GHz Logical "0" 2.4625 GHz Baud rate 1e6…
Vaso
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What does the error "error: ones: invalid data type specified" mean?

This is my code it generates a signal, quantizes it, encodes it, then demodulates it. %Quantization n=8; L=2^n; vmax=8; vmin=-vmax; del=(vmax-vmin)/L; part=vmin:del:vmax; % level are between vmin and vmax with difference…
maz
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Unexplained 'Out of memory' error when using fmmod for FM modulation

I am trying to take an input signal and perform an FM modulation on it in octave. This gives me an unexplained 'out of memory' error. As far as I know, my input file is not excessively large, so I don't know why I get this error. See my trial code…
Rhyston Da Silva
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Remove DC offset in DSBSC signal

I have a file CSV which contains DSBSC modulated signal data.The first column represents time and second column represents amplitudes. I have to demodulate this DSBSC signal to obtain message signal. The DSBSC signal has a DC offset. By plotting the…
karthik
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Simulate LDPC and QAM in MATLAB

I want to study LDPC and I want to simulate a program. This program will use LDPC on a randomly generated 1x32000 size binary array, then it will modulate with 16-QAM, add noise for SNR=20dB, do demodulation for 16-QAM and finally decode it using…
user6210457
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Sending an ultrasonic digital signal with a specific frequency using a raspberry pi and python

For example here is a simple message in binary that I want to send via ultrasound: Bit Stuffing 12 Byte Message (3 Time Stamps) Bit Stuffing 01010101 10100001 00101110 01011001 00101110 10100001 00101110 01011001 00101110 10100001 00101110…
le_lemon
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Are the modulations QPSK, 16QAM and 64QAM analog or numeric?

In the LTE networks, the modulations that are used by the base stations are QPSK, 16QAM and 64QAM according to the SNR. Are the modulations QPSK, 16QAM and 64QAM analog or numeric? I need to know because I am working in the cellular field (but as a…
Bob the builder
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Android app for reading ISO15693 tags with 10% modulation depth

I read a lot about how to develop an Android app that can read ISO15693 transponders. As far as that is all possible and there are a lot of ready-made apps in the PlayStore that do this task. If you look at the reading process with an oscilloscope,…
user13634999
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Python: FM Demod Implementation

I am thinking of analyzing a time-series of some particular values as it were a frequency-modulated signal. I was looking for a Python implementation of an FM demodulator. I know there is a demodulator function in Matlab and Octave; for Python I…
Fabio Capezzuoli
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How to decode amplitude modulation when signal crosses zero?

I'm trying to decode the image signal from a Mitsubishi VisiTel telephone image sender in a C++ program. It is encoded as an analog audio signal modulated with a sine wave carrier of ~1764Hz. I'm reading the audio from the sound card input as signed…
SoftEgg
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Transmit data using sound and recover it on the other PC in MATLAB

I want to transmit data from a PC to another PC using sound. I am trying PSK Modulation but when I play sound of my output signal and record it on the other one, It is very distorted and I can't even notice the phase changes. Am I missing…
Abu Talha
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