# Tagged Questions

the difference between the upper and lower frequencies in a contiguous set of frequencies

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### Processing of speech signals using AMR-WB codec

I have 2 questions related to AMR-WB codec : AMR-WB codec processes the $50-6400\textrm{ Hz}$ frequency band of the wideband speech signal as seen here. Does it mean than it removes the frequencies ...
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### Should I filter before calculating power, if I'm looking for relative changes in power?

I am building a "scanner" sort of program, which reads IQ samples from an rtl-sdr stick, and keeps track of the power on certain frequencies, in certain bands. I am interested in detecting activity ...
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### Bandwidth of lowpass filter?

This article here on the Window method for FIR filter design speaks of the total normalized bandwidth of the lowpass filter in $\textrm{Hz}$ (counting both negative and positive frequencies) ...
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### Advantages of 2-VSB vs BPSK?

Both BPSK and 2-VSB transmit one bit of information per smybol and both modulate the real part of the signal. The difference is, as far as I understand, that BPSK does not modulate the imaginary part ...
17 views

### Doppler frequency to radial velocity in a given bandwidth

given the Bandwidth of the signal (say 20MHz) and Doppler frequency ranging from -100KHz to 100KHz for the Auto Correlation 2D plot. Can somebody kindly explain me what is the radial velocity with a ...
12 views

### Bandwidth of ofdm symbol in a visible light communication system

What is the difference of the bandwidth of the LED and the optical channel? If ofdm symbols are transmitted over this system, is the bandwidth of ofdm symbol equal to BW of the LED or of the channel.
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### Loop bandwidth for symbol timing recovery

I am trying to design the Symbol timing recovery (STR) block of DVBS Receiver. How should I chose the loop bandwidth and damping ratio for determining the loop filter coefficients $k_1$ and $k_2$? ...
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### Does “keying on” a sine wave at a zero-crossing reduce its bandwidth?

I understand that a pure sine wave of infinite duration occupies no bandwidth, i.e. it is only the modulation of a carrier that gives it sidebands. Does the exact timing of a sudden modulation make ...
74 views

### Additive Gaussian white noise - bandwidth

The average power at output when additive Gaussian white noise is present is given by the formula below: $$P_0 = \int\limits_{-B}^{B} \frac N2\ df ,\quad \text{with B being the bandwidth.}$$ My ...
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### What is a $BT$ (Bandwidth-Time) product with reference to modulation?

I would like to know what does Bandwidth-Time product mean. I understand that Bandwidth ($B$) = 1/Symbol Time ($T$), hence $BT = 1$. But how can it vary? What is its significance? e.g. When we say ...
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### Confusion with regards to units in Sinc pulse

I am currently reading a section in the Handbook for MRI Pulse Sequence book where it says that the time-bandwidth product for a SINC pulse is given by: $$T \Delta f = Z$$ where $T$ is the length ...
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### What is the definition of small/large signal bandwidth?

What is the definition of 'small signal bandwidth' and 'large signal bandwidth'? If I google them, I only encounter them in an electrical context (transistors etc.). However, I am looking for a ...
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### Can bandwidth of the closed loop be bigger than bandwidth of individual elements in it?

This is a question from control theory but I hope you can help me with it. I was pointed to this community. So in my control loop I have elements that have cut-off frequency of 3-5kHz and I designed ...
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### What is bit rate? How is it related to bandwidth? [closed]

I am very confused about when to use bandwidth as bit rate and where not. Are these terms one and the same?
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### What is Typical RTP Packet size for H.264 video transmission

I am encoding my video using JM reference software. The encoded file is divided into RTP packets. I can set a RTP packet size in bytes using configuration file. But i am unable to find what should be ...
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### Signal's Fundamental Frequency is different from Plotted Signal

I've been attempting to plot the following function using MATLAB: $$x(k)=\sum_{n=11}^{50} \sqrt{n} \sin (2n\pi k) +\sum_{n=1}^{40}\sqrt[3]{n} \sin (3n\pi k)$$ Note that $k$ is a continuous variable....
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### Extracting multiple signals to baseband

How can I extract a signal to baseband? Rather that just listen to one signal at a time, I want to take advantage of my RTL-SDR's 2mhz bandwidth and listen to multiple FM signals at the same time. I ...
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### Is there a proof that equal bandwidths have equal information-carrying capacity?

Consider a continuous channel, band-limited to the $[f_{\text{min}},\,f_{\text{max}}]$ frequency window. A well-known statement says that, as far as the dependence on the frequencies, the information-...
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### Relation between bandwidth and data rate

I have trouble understanding the following from wikipedia - Bandwidth (Signal Processing) A key characteristic of bandwidth is that any band of a given width can carry the same amount of ...
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### Minimum bandwidth condition in FSK

I know that FSK occupies a larger bandwidth compared other keying schemes, $$BW= f_1 -f_2 +2R_b$$ where $f_1$ and $f_2$ are carrier frequencies and $R_b$ is the bit rate. For achieving a ...
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### Bandwidth of M-ary modulation schemes

I am confused with regard to how bandwidth increases with increase in number of bits transmitted for given duration. 1) Usually say in PCM system, when we increase the number of bits (n) for a given ...
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### I do not understand this simple bandstop filter example

I have a periodic signal like this one with period $T=120$: I would like to apply a bandstop filter to the signal, the stop band should go from 90% of $\frac{1}{T}$ to 110% of $\frac{1}{T}$. So I ...
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### Estimating pole radius of formant filter from bandwidth

I wish to design an all-pole formant filter by specifying frequency θ (between 0 and π radians for Nyquist) and bandwidth Φ such that the response of the filter at θ-Φ and at θ+Φ should be roughly 50% ...
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### Given a discrete signal, how to get bandwidth and duration under MATLAB?

Is there any kind of built-in function or formula that I can use to conveniently compute the (effective) bandwidth and (effective) duration of a given digital signal with known sampling frequency?
188 views

### Is there a condition for bandpass sampling?

Consider a signal that has lowest frequency component $F_l$ and highest frequency component $F_h$. According to the theory of bandpass sampling, this signal can be sampled and succesfully recoverd if ...
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### I still get aliasing of my signal, even though I stay below the Nyquist frequency. What am I missing?

Thanks in advance for any help with my newbie question. I've been consulting quite a large number of resources in order to understand how I can create and playback a nice sawtooth without aliasing, ...
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### How to calculate the bandwidth of a continuous signal?

Can someone please explain how to compute the bandwidth of a signal? Like why the bandwidth of $5\sin(2t)$ is $0$ and of $\sin(2t) + \sin(3t)$ is $1$? Thanks.
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### Bandwidth of a trimmed sinus wave

I generate a sinus which duration is 15ms and frequeuncy of 13KHz. Is its bandwidth is (1/15ms) ? Or in other words, BW = 66.6Hz? I ask that because I have two freqs in my system: 13K & 13.1K. I ...
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### How to calculate the required bandwidth from a spectrum diagram? [FM]

For example from this diagram.
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### Is multirate signal processing involved in ADSL?

Telecom companies offer different data rates for home/office purposes depending on the money they pay. How are the telecom people able to control the flow of data of different cables. Say supposing a ...
209 views

### Matlab coding for bandwidth interval

I have time domain history data. Then, I convert it into FFT to get the frequency domain history data. The problem is, how to determine the bandwidth of the FFT data? Is it automatically synchronize ...
239 views

### Difference between the use of 'bandwidth' in DSP and computer networking

As far as I know, bandwidth is measured in herz or 'radian/second' in digital signal processing or in analog communications. But in computer networking it is measured in 'bits/second'. I don't get ...
62 views

### Internet from Direct Broadcast Serivce

Internet is very much costly in India , like 3-5 USD per GB @ 3G networks and even in broadband 100 USD for a unlimited banwith for 2 MBps but here DTH (Direct-To-Home broadcast service ) is very ...
54 views

### fundamental question regarding bandwidth

What I've learnt so far is that, if we change a time-domain signal into frequency domain, its bandwidth shows the range of frequency of radio waves that required to generate such signal. However, for ...
890 views

### Essential Bandwidth of rect(t/T)

Here is a question I have been trying to solve: Estimate the "essential bandwidth" of a rectangular pulse $$g(t) = \operatorname{rect}\left(\frac{t}{T}\right),$$ with $T>0$, where this "...
191 views

### Bandwidth of an energy signal

I'm studying for my midterm , and I'm struggling with finding bandwidths. I have this energy spectral density : $\Psi(f)= { 1 \over \sqrt { 1 + ({f \over B }) ^2} }$ , and I need to find the $3$...
164 views

### What's the essential bandwidth of the unit step function?

The Fourier spectrum is in the Figure, how to find the essential bandwidth?
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### Sampling rate in Wifi 802.11 -> 20 MHz enough with a BW of 20 MHz?

In a Wifi 802.11n context, I'm looking to find the sampling rate to perform some processing on the signal and I've something I cannot understand : in the book Next Generation Wireless LAN's: 802.11n ...
4k views

### How to calculate bandwidth require for OFDM

I read LTE PHY profile and do not understand the relationship between number of FFT and bandwidth. For example LTE downlink channel bandwidth 1.25MHz and 5MHz have 128 FFTs and 512 FFTs accordingly. ...
120 views

### How is noise variance related to bandwidth?

I have to calculate asymptotic coding gain with soft decision decoding over an uncoded reference system. Lets say the coded system requires a bandwidth $k$ times higher than the bandwidth of the ...
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### Noise analysis with periodogram. problem with different resolutions

I don't understand what happened in my simulation. I would like to perform a trade off between 2 ways to estimate power in frequency bands. I want to detect spurious frequencies. First method: I ...
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### Looking for an algorithm that computes weighted average of frequencies intensity from narrow band in spectrograph

I am searching for the algorithm that takes (audio) signal as an input and outputs weighted intensity of the frequencies of some narrow band (axis X) in time (axis Y). Frequency in the middle of that ...
216 views

### Time-bandwidth product and uncertainty on harmonics

For a signal that is not corrupted with noise, how is the time-bandwidth product affecting the uncertainty or error introduced when extracting the fundamental frequency ? I mean, instead of choosing ...
225 views

### Calculate cutoff frequency of filtered data

I am processing data which was put through a low pass filter at some point. Looking at the FFT, I can see that it is less than the Nyquist rate. I am trying to filter another set of data so that the ...
72 views

### Before the birth of computers how people calculated the bandwidths?

In these days we can able to easily calculate the bandwidths with the help of technology, but in olden days where people used the analog phones, how did they calculated the bandwidths?
150 views

### Creating a time domain filter from a frequency domain plot

In figure 11.23 of Monzingo's Introduction to Adaptive Arrays, the author uses a sinewave in the frequency domain to model the amplitude ripple in the passband of a channel of a receiver. What ...
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### How to calculate BW ofdm?

HI I have these specification for an OFDM program I was wondering, what is the bandwidth and the sampling frequency? I'm not a student of Digital signal processing, hence I am so confused. ...
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### Effects of sampling rate approaching the Nyquist frequency? (not undersampling)

I understand that you need to sample at a frequency greater than or equal to the Nyquist frequency to reconstruct a signal/aliasing etc. I read though that a "more conservative" approach is to sample ...