Questions tagged [bandwidth]
the difference between the upper and lower frequencies in a contiguous set of frequencies
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How to solve this degree $2N$ polynomial equation of filter's cut-off frequency?
In a paper I am interested in, the following equation is given to determine the cut-off frequency $\omega$ of a filter:
$$t^{2N}+\left[-2\left(1-\frac{1}{2Q^2}\right)\right]t^N +\left[-\left(\frac{|H(\...
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Specify notch bandwidth by pole placement
I am trying to implement a notch filter by placing zeros and poles. I found in this thread how to specify the frequency to be filtered out (referred to as $\omega_n$ in previous link,) but it is not ...
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Bandwidth visualization in frequency domain
Consider some signal in frequency domain:
the maximum length of which corresponds to the half of the original signal ($N/2$), here $N=32$.
It is known that the bandwidth of each sample is $2/N$, so ...
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What is the intuition explaining the Shannon-Hartley theorem?
In the digital domain, the signal to noise ratio (SNR) may be interpreted loosely but usefully as the number of discrete or quantized levels one can transmit reliably. For instance, loosely speaking, ...
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How to generate wideband Gaussian white noise
I want to generate correlated complex white Gaussian noise signals in MATLAB. What I do is that I take complex Gaussian random variables with unit-variance and multiply them with the desired input ...
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How the bandwidth distance product rule is applied?
I read the following in one reference:
A copper wire (twisted pair), the link traditionally associated with low bit rate transmission, is still in use in the modern data centers transmitting data at ...
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What is the symbol rate achieved with raised cosine filter?
The bandwidth of the raised cosine filter is w=0.5(1+r)Rs, where Rs is the symbol rate, and r is the roll-off factor. r=0 represents the Nyquist filter, for which Rs=2w.
Any higher value for the roll-...
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How do you prove that the bandwidth of a signal is inversely proportional to the length of the signal?
I am trying to prove the below identity where $f_c(x)=f(cx)$ such that c is a positive number.
$F_c(\alpha)=\frac 1 c F(\frac\alpha c)$
F above represents the Fourier transformed $f(x)$. I attempted ...
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Are there any techniques that can achieve higher transmission rate than Shannon capacity?
The maximum bit rate that can be transmitted over a channel with bandwidth B is determined by Shannon C=B log(1+S/N)
Are there any techniques that could break this limit?
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Why do ATSC channels need 6MHz of bandwidth when they're digital?
If I'm understanding it correctly, an ATSC channel is a digital channel that uses 6 megahertz of bandwidth to send 19.38Mbps using 8VSB modulation. For analog broadcasts, that makes sense, but I'm ...
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Will or can a sampled signal with a limited sampling frequency have infinite bandwidth?
I know that a continuous-time digital signal with sharp edges (e.g. jumping from one y-Value to another discontinuously at the same x-value) will have infinite bandwidth. But what about sampled ...
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how to get the number of bits per symbol?
I have a homework question which is:
A typical telephone channel has the bandwidth of 3100 Hz can support dial-up modems that can variable speeds depending on the quality of the links on both ends of ...
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Why is the bandwidth of each ZigBee channel in the 2.4GHz frequency band 2MHz, while the sampling interval of the ZigBee receiver is 0.5us? [duplicate]
From the Wikipedia, the XBee paper, the BlueBee paper, and the WeBee paper, I learned that:
In the 2.4 GHz band, the bandwidth of each ZigBee channel is 2 MHz.
For receiving a signal over one of ...
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Requirements on Signal Spectrum for Fractionally Spaced Equalization
I'm constructing an ultrasonic communication system and I am struggling with the correct parameters for my receiver.
In baseband, my channel input signal $x(t)$ has infinite bandwidth, since I use a ...
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Which conditions must fulfill a time-limited signal (so of unlimited bandwidth) $f(t)$ to have a bounded maximum slew rate?
Which conditions must fulfill a time-limited signal (so of unlimited bandwidth) $f(t)$ to have a bounded maximum slew rate?
I want to know about which conditions must fulfill a real-valued time-...
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Relationship between sampling rate and bandwidth in gnu radio
I wondering something. While working with adalm pluto sdr in gnu radio, the sample rate I enter in the source block is actually bandwidth. I know that bandwidth must be half of the sampling rate ...
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Consideration about the choice of the radar operating bandwidth
I'm writing an essay about imaging radar.
I was wondering the possible consequences that the bandwidth at which the radar operates could have on the measurements, and therefore on the image.
One ...
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Limiting Bandwidth for QAM and OFDM signal in MATLAB Simulink
currently im creating an application capable of generating QAM and OFDM signal to be transmitted using SDR.
The whole application is implemented in MATLAB Simulink using only code generateable ...
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Super resolution for narrowband signal
How effective it is to apply super resolution techniques (like MUSIC, ESPRIT) on low bandwidth signals for indoor (BW=30Mhz) and outdoor (BW = 1MHz) location estimation?
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What is the Maximum Rate of Change of a BW Limited Signal [duplicate]
If I have a signal that has a max amplitude of 1 and is BW limited by filters to 10Hz-1kHz spectrum. I do not know what the fft/spectrum shape of the frequency looks like and it can change. Is it a ...
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How is it that a dial-up modem can achieve 33.6Kbit/s with only 3100Hz of bandwidth?
My understanding is that plain old telephone service passes frequencies between 300Hz and 3400Hz. How is it that a V.34 modem in the late 90s would be able to achieve data rates of 33,600bits/s with ...
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Signal to noise ratio (SNR) of a CW signal
I understand the formula SNR = 6.02N+1.76 for a N-bit ADC which quantizes a modulated tone sampled at twice the BW. I am trying to understand what the same equation would be for a unmodulated CW tones ...
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Meaning of frequency and bandwidth of a signal, despite the fact that we do not know the signal
First of all, I am completely new to the domain of signal processing.
As far as I know, a signal can be represented with an infinite integral of infinitesimal complex exponentials, which is known as a ...
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From Delay Spread to Coherence Bandwidth?
The phase difference of two sinusoids is given as:
| TX --(r)--->RX <------- (Reflection)|
d: whole path from sender to reflecting object
$ \Delta \theta = 2 \pi \cdot \frac{(2d - r)-r}{c} f + \...
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OFDM use a pulse shaping filter or not?
I've heard in various literature that band limited channels use pulse shaping filters. By the way, In OFDM it use a cyclic prefix to overcome ISI, so I wonder if OFDM does not use pulse shaping filter....
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Bounds of higher order derivative of bandlimited signals
Here is a bandlimited function f(t) with bandwidth Ω:
The function f(t) is bounded in [-A,A].
Then the bound of the derivative of f(t) is bounded as:
|f'(t)|≤2πΩA.
So, what is the bound of its n-th ...
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How can I experimentally find the bandwidth of my PLL?
I recently designed a phase-locked loop. I would like to quantify its bandwidth so that I can better understand it.
However, I made this bandwidth in an informal manner due to my lack of formal ...
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Time domain representation of a modulated signal when symbol rate >> carrier frequency?
I need to understand the relationship between carrier vs. bits with PSK modulation, and what the signal in the time domain would look like if my symbol rate is far greater than my carrier frequency. ...
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Aliasing Issues in Sub Band Coding
The general structure of Sub-Band Coding (SBC) is shown below:
The diagram shows that after each of the analysis filters, decimation is performed by a factor M which corresponds to the number of ...
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Minimum sampling frequency, quantization, and bitrate calculation
An analogue sensor has a bandwidth which extends from very low frequencies up to a maximum of 14.5 kHz. Using the Sampling Theorem what is the minimum sampling rate (number of samples per second) ...
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Bandwidth of PSK modulated signal
What does it mean that the bandwidth of PSK modulated signal without applying any filtering or shaping of the pulse, is equal to the sampling rate with "1st lobe" equal to two times of ...
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Spectral properties of QPSK modulation
From what I've read, the spectral properties of the modulation largely depend on the rate of change of the signal phase - "a signal in which the phase changes stepwise has a broad spectrum, well ...
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Calculating transmitter power from spectral density
I want to find out what is the real transmit power of my USRP 2922, unfortunately the only results I get when looking at the spectrum analyzer is the spectral power density.
These are the results of ...
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Calculating $E_b/N_0$ from given SNR ratio
I have the following formula:
$$\frac{S}{N}=\frac{E_b \cdot R_b}{N_0 \cdot B }$$
Where $S/N$ is of course SNR in dB, $E_b$ is energy per information bit, $ R_b$ is information bit rate in [bit/s], $...
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Transceiver for TDoA measurements
Could someone advise me on some module for making the TDoA position system for my research work? I need to have measurements with an accuracy of a few meters. It equals a bandwidth of about 20 MHz. I ...
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LoRa sensing using USRP GNURADIO
I made a simple RF sensing using USRP N210. I am trying to detect LoRa transmission.
A LoRa Node is operating at 915 MHz with Spreading Factor 8 and bandwidth 500 kHz.
I have used a USRP UHD Source ...
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How do we calculate bandwidth from signal formula?
How can we calculate the bandwidth of distinct signals like this?
I guess the right answer is 90 - 10 = 80 Hz. But I have a hard time understanding why is this calculated in that way. I thought the ...
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how sinc pulses can be used to distinguish different symbols
Let's say we want to transmit a sequence of numbers Using PAM, this sequence is transmitted with the signal $s(t)$
The pulses in $s(t)$ are transmitted at a rate $R_p=\frac{1}{T_p}$. This is called ...
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Determine the change of selectivity
I've stacked on solving this problem and can't find an answer in the web, so I decided to ask a question here.
There are the problem:
Preselector of boadcast receiver contains of one oscillation ...
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Wideband FM bandwidth estimation
In the book Modern Digital and Analog Communication Systems by B. P Lathi, there is a section for the estimation of WBFM bandwidth. First, the staircase approximation of $m(t)$ is constructed by the ...
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Confused on Pulse Filter Bandwidth and Symbol Rate Relation
***Still need help in 2021 - not fully clear still on Jan 20th ***
I am confused about the relation between Sinc and Rectangle transform pair and how that relates the Bandwidth of Pulses, Bandwidth of ...
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Bandwidth of a bandpass signal
If the Fourier transform of an aperiodic continuous time signal has signal components between the minimum frequency w1 and the maximum frequency w2, but not all the frequencies between w1 and w2, is ...
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Find the Equivalent Noise Bandwidth
I have already asked (in another thread) how to quantify (specify) the window function I have created. One figure I need it seems is the Equivalent Noise Bandwidth (ENBW) Or Noise Equivalent Bandwidth....
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Es/N0 with roll-off
I was trying to figure out if the relationship between SNR and Es/N0 changes with roll-off factor.
$W$: RF bandwidth.
$B$: Base band bandwidth. $W = 2B$.
$E_s$: Symbol energy.
$P_s$: Symbol power.
$...
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Why the bandwidth in frequency spectrum of AM wave is 2fm and not 2fc?
We know, the instantaneous voltage of AM wave is:
...
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the best pre emphasis for MMSE equalizer
The system consists of multiple low-pass filter and noise, $h_1$, $h_2$, $h_3$, ..., $n_1$, $n_2$, $n_3$, ...
At the transmitter, the power of signal is fixed; and at the receiver, MMSE equalizer is ...
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Bandwidth of a modulated signal in analog domain
If i am using QPSK modulation with data rate 4 Mbps with rolloff factor $0.5$, then the bandwidth will be symbol $\rm rate\times (1 + rolloff\ factor)$. So here it will be $\rm 2\ MHz\times 1.5 = 3\ ...
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What is role of BW and frequency in internet speeds?
First the bandwidth (BW):
It is the amount of data that can be transferred simultaneously.just like more no. of highway lanes so that many cars can travel side by side simultaneously.
Frequency
It ...
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What is the physical meaning of coherence bandwidth in mmWave massive MIMO channel?
I am doing some research about millimeter wave massive MIMO channel now.
We first take account about static MIMO channel, cause we only have SISO measurement system now.
We use scanner to move our ...
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Design and a notch filter using two Butterworth filters in parallel (MATLAB)
I am doing a project to filter out a 1kHz noise inserted to a 30sec .wav audio file.
To filter out the 1kHz noise, I am required to design using two Butterworth filters connected in parallel where ...