# Questions tagged [snr]

Signal-to-noise ratio (often abbreviated SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise.

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### Using matlab to simulate SER VS SNR of 4QAM [closed]

I'm trying to use Matlab to simulate SER VS SNR of 4QAM. For example, transmitting a 1+j symbol but received -1-j, but I couldn't get the plot.
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### Sample & Hold: Estimate jitter delay of an ADC

I've got a question regarding the effects of sample and hold. My input signal is $x$, and my output signal $x_{SH}$. The error between the signals is $e_{SH} = x_{SH}-x$. The sampling frequency is ...
26 views

### Probability of error QPSK

Calculate the probability that the received symbol when the transmitted symbol is 1+j that lies on the first quadrant and the received symbol lies in the third quadrant. How do I use the ...
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### simulating directional interference to evaluate model performance

I have a model for audio processing. The model receives as input, a source, convolved with a room impulse response (RIR). I would like to test the performance of the model against inputs containing ...
43 views

### Measuring the SNR at output of matched filter

If I input a noisy signal with a calculated value of SNR, into a matched filter, then I get a matched filtered output, which should be a sinc function. I want to calculate the matched filtering gain ...
36 views

### Calculate SNR from packet error rate on micro-controller unit

I have the problem of calculating the Signal to Noise Ratio for a packeted transmission using FSK or BPSK modulation with convolutional coding on a micro controller unit which communicates with an RF ...
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### Compute SNR for a noisy signal in Python [duplicate]

I have a discrete signal represented by an array in Python: $x \in R^N$. Now I add Gaussian noise to x: $x = x + np.random.normal(l=0, s=1, size=x.shape)$. How can I compute the signal-to-noise ratio ...
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### What's wrong with my M-ary ASK modulation demodulation MATLAB code?

My MATLAB code linked below implements ASK modulation of an M-ary signal, impresses it on a carrier, adds AWG noise of various SNRs. Then, for each SNR, demodulates the signal and calculates the ...
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### Doppler effect in underwater acoustic channel

I got my BER vs SNR graph as shown. I was trying to show the difference in BER with OFDM signal transmission under Doppler effect and without Doppler effect. However, based on my understanding, the ...
91 views

### When calculating SNR, is noise included in signal?

Given a signal $x(t) = s(t) + n(t)$ where $s(t)$ is the desired signal voltage and $n(t)$ is the noise, should the signal to noise ratio of this signal be 20log(xrms/nrms) or 20log(srms/nrms)? i.e., ...
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### How to calculate relative SNR (or similar) in a set of noisy audio samples with underlying identical signal

I have a set of audio samples that were recorded at the same time of a single source. Each sample has a different amount of noise so I don't have a clean sample of the underlying signal. Ideally, I'd ...
35 views

### Measure How Much Pattern Is Present In Signal

I have some pattern signal. This pattern signal will be played in noisy room. Then it will be recorded and processed. I need to show that my processing algorithm improves the signal. My idea is to ...
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### Signal Averaging

Note I also asked this in math stackexchange I was reading a wiki page about signal averaging specifically in the section Signal power for sampled signals. At least at first glance the information ...
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### Simulate BER curves for OFDM with convolutional coding

I am tasked with generating performance curves for an OFDM transmitter/receiver, and I am unsure how to calculate the appropriate AWGN power, and where exactly the apply it. The transmitted packets ...
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### Frequency Domain Signal to Noise Ratio

I am doing some research on low-cost air pollution sensors. I'm measuring the "ground truth" with a single low-noise sensor, and I'm trying to use it to calibrate a low-cost sensor that has high noise....
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### channel gain calculation

I want to calculate the SINR term in an up-link of wireless communication system but there is different models for simulation. I want to know what is the exact meaning of |h|^2 in this formula: SINR = ...
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### Capacity achieving codes for BPSK at low SNR

I don't know a lot about comm system design. I have an AWGN channel and low SNR (-3dB). Bandwidth is constrained to some maximum, B. I would like to know good choices of modulation and coding to ...
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### LOW SIGNAL NOISE RATIO FFT

I am processing an audio signal with CS4244 codec at 24 bits and 48kHz. Every 2048 samples the FFT is calculated and its amplitude. Without input signal I get FFT values ​​close to 30dB. With maximum ...
56 views

### SNR and Correlation

Signal to Noise ratio is essentially the ratio of the signal power to the average noise power. Correlation is the similarity of two signals. Assuming a signal travels through a channel or medium, and ...
19 views

### Should PSD be smoothed for SNR computation in frequency domain?

When taking the Power Spectral Density of a short duration signal (say 1 second, sampled at 4096 Hz), should it be smoothed to compute SNR? I want to computed the matched filter SNR, perfectly knowing ...
175 views

### Generate signals with a particular variance and SNR

Consider a system model of the form: $y_n = ax_n + v_n$ where $x_n$ is the input that is corrupted by $v_n$ which is an Additive White Gaussian Noise of zero-mean and variance 1 for $n = 1,2,...,N$ ...
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### SNR computation in frequency domain with scipy.fftpack.fft

I have a noisy time series (gaussian coloured noise) to which I add a signal. I call the sum of noise+signal a segment. In the picture you can see an instance: I want to compute the signal-to-noise ...
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### On generalizing Gabor-Heisenberg uncertainty in a noisy environment

The Gabor-Heisenberg uncertainty represents the fundamental limit of time and frequency resolution one can extract from a signal. $\sigma_t \sigma_f \geq \frac{1}{4\pi}$ My question is: what happen ...
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Suppose that I have a BPSK modulated multicarrier carrier waveform $L$ samples long at a sampling rate of $f_{s}$: $$x_{tx}[l] = \sum\limits_{n=0}^{N-1} A \cdot \cos\left(2 \pi \frac{f_{n}}{f_{s}} ... 0answers 239 views ### How to measure SINAD of an audio signal? I tried to measure the SINAD and SNR of a recorded audio signal using MATLAB. The following is the process I did to measure the 2 parameters: Firstly, I generated an FM modulated signal(1 kHz audio ... 2answers 71 views ### Combining SNR Measurements [closed] If I have two SNR measurements (i.e SNR1 = 15, SNR2 = 20), how do I calculate a combined SNR? In my example, would this be SNR_Total = 35? 1answer 72 views ### How to calculate SNR with sample noise and noisy signal only I want to calculate the SNR for a speech signal recorded within a noisy environment. I also sampled purely the noise within the environment. The SNR is based on the ratio of power of clean signal ... 0answers 26 views ### How do you evaluate a denoising algorithm when all you have is the noisy data? I'm currently working on denoising acoustic signal used in leak detection so that the leak detection could be more accurate. The thing is noise can come from various sources (Car or people passing by, ... 0answers 50 views ### Find a simple sine wave buried within noise, FFT or cross-correlation? My recorded signal x = s + v, where s = A*sin(ωt) and v = noise. SNR < 1 or ~ 1. So the sine wave is buried under a lot of noise. I need to compare the relative amplitudes of s for each recording ... 0answers 19 views ### Getting SNR of reconstructed signal in MATLAB I am trying to run code to compare the efficiency of various basic sampling methods such as ideal sampling, natural sampling and so on. I want to then use average power to see how accurate the ... 0answers 49 views ### Find the SNR of an FM broadcast signal in GNU Radio? Any ideas on how to find the SNR of an FM broadcast signal in GNU Radio? I have seen an SNR estimator block for MPSK modulation? Do I need to create an OOT block for calculating SNR of FM signals or ... 1answer 234 views ### Optimal amplitude of an m-bit sinusoid A continuous-time sinusoid of zero-to-peak real amplitude A \le 2^{m-1}-0.5 (e.g., for m=16, A \le 32767.5) is quantized to m-bit resolution by rounding it to the nearest integer (Fig. 1). ... 0answers 11 views ### Why can the C5 formula also means that \sum\limits_{k=1}^{K}tr(\mathbf F_{K4E})>P_T? In this paper:https://arxiv.org/pdf/1805.08898.pdf I can understand why C4 means P_E > P^*,I just need to times 1-\rho_k in both two side,the C4 will become (1-\rho_k)[\sum\limits_{k=1}^{K}\... 0answers 21 views ### Can the j be equal to k in the first formula ?In MISO system In this system model,the received signal available for RF EH at each RX_k is given by However,its SINR formula is given by We can find that author said the j can't be equal to k,but their range are ... 1answer 165 views ### GnuRadio's SNR estimators usage I'm trying to calculate the SNR of a satellite signal using GRC, but all of the 4 offered estimators either have a lot of -NaN values or are ~35dB throughout the entire recording. (I just connected ... 0answers 46 views ### On-target SNR measurement I want to measure the performance of a receiver demodulation algorithm, something like Bit Error Rate as a function of the power of the incoming signal (in dBm) and compare it to simulation results. ... 0answers 46 views ### Advances in Blind SNR estimation beyond M_2M_4 In Pauluzzi and Beaulieu, various SNR estimation methods are compared. Among the blind methods considered, the M_2M_4 estimator seemed to be unambiguously the best. However, it has been shown that ... 3answers 58 views ### Confusion about decibels I know that \text{dB} actually represents dimensionless value, meaning, it is the ratio of two values that have the same dimension, for example:$$p_1=10\log\frac{P_1}{P_0} $$This can be ... 1answer 353 views ### Input and Output SNR Calculation in AM receiver input and output For the FOM calculation of an AM receiver, the input and output signal powers are respectively,$$P_{in} = \frac{A_c^2(1 + k_a^2P_m)}{2}P_{out} = k_a^2A_c^2P_mThese are obtained from the input ... 1answer 82 views ### Why does SNR have an impact on the bit rate? I have some confusion regarding the impact of SNR on the bit rate. For example, if I have a QPSK-OFDM system, then my bit rate will be 2bits mutiplied by the number of sub-carriers of the OFDM ... 2answers 687 views ### Measuring microphone Signal to Noise ratio (SNR) with A-weighting Foreword: I have already read Applying A-weighting and user @endolith's A-weighting code I would like to measure the SNR of a microphone with the same method applied by the main manufacturers, that ... 1answer 41 views ### SNR in one-dimensional additive channel with uniform noise and binary antipodal input A one-dimensional addictive noise channel, Y=X+N, has uniform noise distribution N \sim U(-\frac{L}{2}, \frac{L}{2}) and binary antipodal input constellation with equally likely input values x=\... 1answer 56 views ### finding the audio pulse compression peak in extra-low SNR scenario? I just want to obtain some general ideas for such a scenario: if the environmental noise is extremely strong and the audio signal at the receiver is extremely weak(for instance, low range propagation),... 1answer 435 views ### Downsampling impact on complex phase For my application, I have to downsample a bandpass complex signal which spectrum is located on the second Nyquist zone. Knowing that this processing will cause a spectrum inversion, what would be ... 1answer 537 views ### Calculating SNR from Frequency-time domain I tried to analyse the time-frequency of specific appliances. As it shows in the following frequency-time graph I have High frequency noise from different appliances here. 4096 is the number of ... 1answer 39 views ### The computation procedure problem of calculating the BER Here is the processing of calculating the BER average \begin{align} P_e &=\int^\infty_0Q(\sqrt{2uSNR})e^{-u}du \\ & =\frac{1}{\sqrt{2\pi}}\int^{\infty}_0\int^\infty_{\sqrt{2uSNR}}e^{-\frac{t^... 1answer 2k views ### Calculating SNR from Frequency Domain As I am newbie to signals, I have collected an appliance signal in frequency domain as follows: (PSD- Power Spectral Density). So, I need to calculate the SNR (Signal to Noise Ratio) and BER (Bit ... 2answers 376 views ### Mean delay for a M tap harmonically weighted filter I am trying to derive the mean delay for M filter taps harmonically weighted:y[n] = \frac{M\,x[n] + (M-1)x[n−1]... + 1 \cdot x[n−M+1]}{\tfrac12 M (M + 1)}. For a uniformly weighted filter, I ...
I am using an optical spectrometer to measure the reflectance of some surfaces; the output is essentially a set of photodiodes' signals: for each photodiode I have a discrete time signal every $T$. ...