Questions tagged [bandwidth]
the difference between the upper and lower frequencies in a contiguous set of frequencies
173
questions
2
votes
1answer
41 views
Detection Bandwidth for Noise Power Calculation
I am trying to calculate the $P_{noise}$ in an experimental setup, such as given
below. The DUT is excited at a predefined frequency, $f$ , with
power $P_\text{in}$. The total power is measured by the ...
-1
votes
2answers
52 views
flat fading and Nyquist minimum bandwidth
For flat fading, the bandwidth of the transmitted signal must be less than than the coherence bandwidth of the channel, and no intersymbol interference (ISI) occurs.
Nyquist showed that the ...
1
vote
1answer
42 views
frequency band and Bandwidth
All I know so far is that frequency is how much a signal repeat it self in a given amount of time (usually one second), like shown in the following figure:
I'm confused with some concepts like ...
2
votes
3answers
288 views
Why we measure bandwith at -3dB?
To characterize a signal it's a common use to determine bandwidth at -3dB from the peak (half power). Also, filter's cutoff frequency is pointed at -3dB. Why we use this rule?
0
votes
1answer
41 views
How to generate IQ samples of a signal?
I am using a HW with LMS7002 RF transceiver chip. This chip takes IQ values as an input.
1. Can anyone point me to a sample IQ value generator? That I can use to test.
2. What will be the IQ values ...
0
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0answers
43 views
Calculating the power spectral density on a different bandwidth
Let us say I have the power spectral density for a given bandwidth F1 at a transmit power T. I would like to calculate the power spectral density for bandwidth F2 for 1) the same transmit power T
2) ...
0
votes
0answers
42 views
Bandwidth of a signal
Given a complex,with fmin<0(say -10) and fmax>0(say 30) what is the bandwidth of this signal.Is it form fmin to fmax ,or 0 to fmax?
Thank you!
0
votes
1answer
31 views
What is the unit for power spectrum of acceleration signals in log scale
I have a signal recorded by an accelerometer in m/s^2. It is basically accelerations over a period of time. I have calculated the power spectrum of the signal over in a certain frequency band and then ...
-1
votes
1answer
43 views
Bandwidth and probability of continuous signal
I'm a little bit confused as to how to calculate the bandwidth of a signal. A question has me believing that it is correlated with the probability distribution. I am however not sure of this.
...
2
votes
1answer
33 views
Bandwith of a energy signal
I'm studying for my finals , and I'm struggling with finding bandwidths.
I have this energy spectral density : Ψ(f)=rect(f) , and I need to find the bandwith, 3 dB band and the band with 90 % power.
...
0
votes
2answers
101 views
What's the theoretical bandwidth?
A radio signal is sampled at $f_{s}=5512$ Hz, and $n=2^{14}=16384$ points are used in the FFT to display it as a spectrogram.
The frequency resolution is $\frac{f_{s}}{n}=0.33642578125$ Hz/point, ...
0
votes
1answer
107 views
duty cycle of a WiFi Packet
I am doing a simple over-the-air(WiFi 802.11a) test in a shielded chamber involving one Tx and one Rx (around 5 feet).. I need to find the duty cycle given the length of the payload (in bytes), MCS ...
0
votes
1answer
59 views
When can a windowed cosine be considered band-limited signal?
I have an exam in the following days and i have no clue of what is the response to this question in the exam:
given this signal:
$$g(t) = H\left(t+\frac{T}{3}\right) f(t) - H\left(t-\frac{2T}{...
1
vote
1answer
71 views
sum of 2 signals
I have $2$ signals: $x(t)$ and $y(t)$. They have the same bandwidth $B_x=B_y$. But the bounds for the bandwidth are not the same. For example, $B_x=f_{max}-f_{min}$ and $B_y=g_{max}-g_{min}$ with $f_{...
1
vote
2answers
77 views
How to generate random data with a specific bandwidth
I generate some random data (bits, actually, using MATLAB's randi) and then I convert such bits to BPSK (1 and -1). After that, I use a RRC pulse (roll-off factor ...
0
votes
0answers
26 views
Digital Spectrum Analyzer: Video Bandwidth
I am currently working on a Digital Spectrum Analyzer. We are trying to imitate a hardware Spectrum Analyzer by capturing I/Q data and performing an FFT on it. I am a bit stuck on how to imitate the ...
0
votes
0answers
26 views
How to add multiple sub bands of frequency into on wide band
Context:
I am doing a project where I have to sample a video signal from a monitor with an SDR. The data is coming in for each pixel left to right top to bottom.
Since my receiver doesn't have a very ...
0
votes
1answer
198 views
Do negative frequencies count towards null-to-null bandwidth?
I am aware that negative frequencies do not normally count towards the bandwidth when transmitting in the baseband. However when specifically asked to look at the null-to-null or zero-crossing ...
0
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1answer
558 views
Relationship between signal rate, data rate, minimum bandwidth
I need to understand the relationship between bit rate, signal rate and minimum bandwidth. I read in a textbook that
We define three cases for relationship between bit rate and signal rate for ...
2
votes
1answer
79 views
Representation, Bandwidth and composition of Digital Signals
I have started learning data communication and I'm not able to grasp certain topics.
First
(i) I know that analog signals are continuous and digital signals are discrete. Analog signal are ...
0
votes
0answers
33 views
Doppler Spread and Doppler Spectrum
I am a bit confused about Doppler spread and Doppler Spectrum. I believe the Doppler spread is related to channel coherence time T_c, so that . Due to inconsistencies and incoherency of the channel, ...
1
vote
3answers
116 views
Why bit rate is same in a lower frequency spectrum and higher spectrum?
If there is a spectrum between 0 Mhz - 1 Mhz, bandwidth would be 1 Mhz here and for example with baseband we can send 2000 bps. What I can't understand is if spectrum is 5-6 Mhz instead of 0 - 1 Mhz, ...
1
vote
1answer
718 views
Nyquist Maximum data rate formula for PCM
The Nyquist maximum data rate formula for a binary PCM is given by
$$C = 2B\log_2L$$
I'm not very sure what "$B$" is here. Is it the bandwidth of the signal being sampled or is it the channel ...
2
votes
1answer
84 views
Find Bandwith from Spectral Efficiency and Eb/N0
to give you a short intro of why I am asking here. My Uni is offering a TeleCom Lecture, I love the topic but all they teach is electronics, the exercise sheets are still TeleCom, we get no supporting ...
1
vote
1answer
104 views
Bandwidth of a finite impulse response filter
In a machine learning application, a model learns to apply a filter h(n) via convolution to a 1-dimensional input signal s(n) (e....
1
vote
1answer
224 views
Calculating Data Rate using Bandwidth, Transmission Power, Noise Power Spectrum Density and Channel Gain
I'm a Software Engineering student researching on Load Balancing in IoT and I need to calculate data rate. However, I don't know how to use these values to attain data rate despite searching on the ...
0
votes
0answers
18 views
What is a transmission rate of 802.11a WIFI radio?
I am trying to understand the transmission rate at which a WiFi radio sends its packets to other radios ?
Like in DSRC (which is 802.11p system) , DSRC Radio broadcasts its message 10 times a second ...
0
votes
0answers
179 views
Notch Filter with given Bandwidth
I have to use Matlab with the iirnotch()-function to design a notch filter. The notch should sit at 520Hz, the Bandwidth should be 100Hz and I have a sampling ...
0
votes
0answers
20 views
Binary Polar vs 4-PAM Signalling
Why is binary polar signalling not feasible for a data rate of 2.0Mbps within a bandwidth not exceeding 1MHz?
Is it due to the fact that binary signalling can only transfer 1 bit of data per symbol ...
0
votes
1answer
107 views
Appropriate channel bandwidth for my BPSK modulated Psuedo-Random code on direct conversion transceiver
My hardware is an analog device SDR+Xilinx FPGA (sdr = fmcomms4-ebz). The direct conversion transceiver (ad9364) has a tunable channel bandwidth of 200Khz - 56Mhz. I am employing BPSK modulation on a ...
2
votes
1answer
618 views
QPSK Data Rate vs Bandwidth at Passband: Why can it only transmit 1 bit per Hz and not 2 bits per Hz?
1) This is a follow up question to the most up-voted answer to this question.
2) The accepted answer is that "QPSK transmits 1 bit per Hz at passband".
3) The theory found in books seems to agree ...
0
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0answers
80 views
Chirp resolution as a function of bandwidth
My question concerns about the Chirp resolution during the crosscorrelation as a function of the sampling rate and available bandwidth. Suppose at a transmitter a chirp signal is transmitted (ranging ...
1
vote
1answer
144 views
How is frequency related to data rate?
How does (if it does) frequency affect/relates to Data Rate.
Why for example using the same modulation, LoRa (in the physical layer),
you get somewhere around 250kbps at 2.4Ghz and only 20kbps at ...
0
votes
1answer
284 views
What is the meaning of inverse signal bandwidth?
I have been studying the two ray model in communication systems.
The text I'm studying has two signals, $u(t)$, which is Line of Sight and $u(t-t')$, which is the reflected signal.
It quotes,
...
0
votes
2answers
563 views
Noise power and bandwidth
$$N=kTB$$
In this formula for calculating noise power, why do we use the total bandwidth of the system?
I mean our signal is at $f_0$ carrier frequency, why is it effected by a large bandwidth and ...
1
vote
1answer
1k views
Minimum Channel Bandwidth for PCM
Please check if my answer to GATE IN 2010 question 11.20 is correct/can be improved upon.
So, every $\frac{1}{f_s}$ sec, a sample is taken. The signal amplitude is quantized into $2^n$ levels such ...
0
votes
1answer
3k views
Passband vs Baseband Bandwidth
Bandwidth is the difference between the upper and lower frequencies in
a continuous band of frequencies. A key characteristic of bandwidth is
that any band of a given width can carry the same ...
0
votes
1answer
66 views
Bandwidth of the Derivative of a Message [duplicate]
If I have a message signal $m(t)$ and it has a bandwidth $B$. I know that the bandwidth of $m^N(t)$ is $NB$. But what is the bandwidth of $\frac{d m(t)}{dt}$?
Thanks!
5
votes
1answer
148 views
Bounds of the difference of a bounded band-limited function
For a continuous signal (function), we have Bernstein inequality :
$$
|{df(t)}/dt| \le 2AB\pi
$$
where $A=\sup|f(t)|$ and $B$ is the bandwidth of $f(t)$. The question is: is there a relationship ...
0
votes
1answer
80 views
What is an intuitive understanding of the difference between the minimum required bandwidth and actual bandwidth?
When using for example, polar signaling of full width rectangular pulses, the bandwidth is equal to the pulse rate $Rb$, which is also the bit rate.
$B=R_b$ for full width rectangular pulses.
But ...
0
votes
2answers
616 views
Quantization level versus bandwidth [closed]
Why is it that increasing the number of quantization levels $L$ results in an increase in the signal's bandwidth?
8
votes
2answers
575 views
Bounds of the derivative of a bounded band-limited function
Let $f(t)$ be a function with properties:
$$\begin{array}{ll}
t\in\mathbf{R}&t\text{ is in reals}\\
f(t)\in\mathbf{R}\text{ for all } t&f(t)\text{ is in reals}\\
|f(t)|<A\text{ for all }t&...
0
votes
2answers
147 views
Why Shannon Theorem has nothing to do with frequency?
According to Shannon theorem
$$C= B \log _2(1 + S/N)$$
My question is, why there is no frequency in this formula?
Let's say we have 2 channels, both of them have same 20 MHz bandwidth,
one is from ...
1
vote
2answers
72 views
Modulation and allocation in GSM900
I want to do one project and I just want to make sure that I've understood correctly.
Human's voice frequency is around 85-255Hz.
When we talk on phone, carrier is modulated with voice signal in ...
5
votes
2answers
517 views
Intersymbol interference due to limited channel bandwidth
What is the difference between limited-bandwidth induced intersymbol interference (ISI) and ISI due to multipath propagation.
I noticed that the delay spread in indoor environment is in the range of ...
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vote
0answers
44 views
How can I design a PI controller for a closed loop system, which requires a bandwidth equal to the natural frequency and a set Phase Margin?
For a school project I have to hand in a small report on a this problem. I've been studying so much for it but right now I'm just mixing up everything I've seen and just don't know where to start. I'd ...
1
vote
1answer
1k views
How Does the RMS of White Noise Change with Sampling Frequency?
There is an analog system which includes the continuous-time linear equalizer (CTLE). With some .noise analysis the power-spectral density (PSD) of the noise in that system is provided. So let's not ...
2
votes
1answer
246 views
Bandwidth of Information Signal
I have trouble finding the bandwidth of a signal. Say I have an info bearing signal m(t)=sinc(2t/pi). I found the fourier transform of the sinc function and found that the angular frequency was 1/pi. ...
0
votes
1answer
55 views
Separate speech signals that are bandlimitted
I have 2 kind of signals (refer figures) in a folder. One is band limited to 4khz and another is band limited to 8khz, both are with sampling frequency 16khz. I need to separate them. Any idea??
1
vote
2answers
403 views
Short length windowed sinc filter
I have a 50-60Hz signal being sampled at a frequency of 25 kHz & I'm trying to filter all frequencies beyond 70 Hz with a reasonable steep transition band (approx 4 Hz) & good attenuation (~40+...
