Questions tagged [analog]
The analog tag has no usage guidance.
78
questions
0
votes
1answer
39 views
Modulate Bipolar(?) signal
I want to modulate this signal if possible with an Arduino, but have no idea what circuit can help me here. Let's ignore the timing and the measurements from the image for a moment, my problem is more ...
3
votes
1answer
49 views
Why is a bandpass filtered analog PM signal still PM and not AM
I know, that in theory a sinusoidally phase modulated (PM) signal with an expression like $\Re(e^{\mathrm{j}k\sin(\omega_s t)} \cdot e^{\mathrm{j}\omega_ct})$ with the signal frequency $\omega_s$, the ...
0
votes
1answer
50 views
why don't we use Broadband technology to transmit digital signals ,and use Baseband technology to transmit analog signals? [closed]
I learn the Broadband technology and baseband technology in this website: https://www.computernetworkingnotes.com/networking-tutorials/differences-between-baseband-and-broadband-explained.html
...
1
vote
1answer
132 views
Are there analog re-configurable filters?
I know that we can build a chip (or circuit) or use FPGA to have re-configurable digital filters. But how about analog filters, can we have re-configurable analog filters?
thanks
0
votes
1answer
159 views
Analog Square Root Raised Cosine Filter
I am wondering if it is possible to realize an analog square root raised cosine filter.
Any idea about how to do that with Matlab?
0
votes
1answer
42 views
How to convert between function forms of single frequency signals
I have an equation x(t) = (3+4j)*e^(j*8*pi*t)+(3-4j)*e^(-j*8*pi*t) and am trying to convert between this and shifted sines and cosines. I'm attempting mash this through euler's formula and got a 10 ...
0
votes
0answers
35 views
Is this PSK or FSK
I am analysing a captured 433.92MHz signal sampled at 2MHz:
If we zoom in:
I am thinking this is PSK? Am I wrong?
Thanks
0
votes
1answer
37 views
Obtaining a high sample rate digital approximation to an analog filter from lower frequency measurements
Consider a set of dense, but generally irregularly-spaced frequency response measurements of some real low-pass analog filter. Denote the maximum frequency for which a frequency response measurement ...
1
vote
1answer
49 views
phase response of an analog filter
I am trying to understand the relation between phase response of an analog filter and its influence on the quality of a signal with PSK modulation.
For example I want to design a BPF for HF ...
1
vote
1answer
223 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., ...
0
votes
1answer
162 views
Binary and Quadrature Phase Shift Keying [duplicate]
I was learning Modulation Techniques and was on the topic Phase Shift Keying (PSK). As far as I have understood,
In Binary PSK we encode a single bit on a one signal element and we differentiate ...
0
votes
1answer
42 views
The phase of signal when it passes a frequency divider?
When we used the microwave frequency divider, such like: RF Bay FBS-N-14 or analog dividers in wiki.
The input signal is $\cos(\omega t+\phi)$, and the output signal is $\cos(\frac{1}{2}\omega t+\...
3
votes
1answer
206 views
Compensating the Group Delay of an Analog Filter using DSP
I am having a problem in my current project where I need to measure different biological signals (like ECG) simultaneously.
As the instrumentation hardware is developed by different people over time, ...
3
votes
1answer
85 views
analog-to-discrete-to-analog system sampling problem
This is not a homework problem, I am solving practice problems for my exam.
Consider the analog-to-discrete-to-analog system shown in figure 1. The CT signal $x_a(t)$
is sampled at a frequency of $...
0
votes
2answers
102 views
Is it possible to just remove the noisy part of signal?
Is there a way to scan through a signal and remove the parts that don't look "normal". This would mean using more advanced then a simple pass band filter, but something that can look at a period in ...
1
vote
1answer
110 views
Signals sampling
I have a simple question, but sadly I'm kind of "noob" in signals theory.
A signal having 4 harmonics at the following frequencies: 1 kHz, 2 kHz, 3.5kHz and 4.2 kHz.
(How can a signal have harmonics "...
1
vote
1answer
54 views
How do I add more resolution / taps to an analog -> digital filter?
(I am trying to create an IIR audio filter that adds reverb to an initial sample)
Say I designed an analog filter to model acoustic attenuation based on the following mathematical model:
$$
I = I_0 ...
1
vote
0answers
90 views
Digital or analogue filtering?
I'm trying to self learn the art of signal processing whilst moving through my third year pure maths degree.
Sorry if my terminology is incorrect however I hope I am understandable!
I am looking at ...
0
votes
1answer
144 views
Is it possible to encrypt an audio wave? NFL Example
In the NFL, quarterbacks receive playcalls from coaches over their helmet's wireless interface.
Someone mentioned how occasionally, these radios will pick up interference from airplanes, and that ...
0
votes
1answer
258 views
OFDM RF signal waveform
From the Wikipedia article:
"An inverse FFT is computed on each set of symbols, giving a set of complex time-domain samples. These samples are then quadrature-mixed to passband in the standard way. ...
0
votes
1answer
132 views
confusion between frequency and amplitude in digital to analog and vice versa conversion
bandwidth is defined as the difference between the highest frequency and lowest frequency.
amplitude is the distance between the, let's call it a crest and a trough, in a wave.
cycle is the time per ...
0
votes
5answers
116 views
How Can Telecommunication System Know Which Part Is Signal and Which Is Noise? [closed]
When signal is received how can receiver know which part of received signal is signal and which part is noise??
3
votes
1answer
496 views
Proof-of-concept for active noise cancellation to block consistent low-frequency HVAC noise transmission
Background
We live in a multi-unit building where each unit's HVAC system/closet is located directly across a party-wall from the neighboring unit's bedroom, and adjacent to a shared external curtain ...
2
votes
1answer
1k views
How to simulate analog VU meter response to audio?
I'd like to simulate the movement of an analog VU meter dial as shown below and often found on stereos and other music monitoring equipment.
I just learned through this article by Rod Elliot (ESP) ...
-1
votes
2answers
709 views
Amplitude ranges for different bit-depths
In Python, I am using the library Soundfile (which uses the library libsndfile) for digital sound processing. I am working with different sound files coming from different internet databases, and ...
0
votes
2answers
285 views
Analog vs digital
If there are means to process all signals after they have been captured and digitilized, why are we still designing ICs to do analog signal processing? For any giving case, can not we just digitilize ...
0
votes
3answers
314 views
How to calculate the frequency response of LTI system based on measured impedance
I have an analog circuit containing unknown resistance, capacitance, and inductance. I have measured its complex impedance across the frequency range of interest. Is there an equation that will allow ...
-1
votes
1answer
104 views
Can I apply CWT on a digital signal?
First, I am so sorry for my dumb and stupid question, I am very beginner with signals.
Say that I have an ultrasonic sensor cabled to an ADC (Analog to Digital Converter).
The ADC converts the analog ...
0
votes
2answers
103 views
Analog Integrator Sampling Rate
What would be the effective sampling rate of an op amp analog integrator (such as the one described here ) taking in a rapidly varying signal be? Ie what time resolution would such an integrator have? ...
62
votes
4answers
20k views
Why is TV static noise always black and white?
Most modern day Cathode Ray Tube (CRT) televisions manufactured after the 1960s (after the introduction of NTSC and PAL standards) supported the circuit-based decoding of colored signals. It is well ...
1
vote
0answers
90 views
Processing digital sound in Audiokit to sound like the 1960's
I am looking to imitate 70's analog equipments sound. I was wondering is there a way to create tape saturation / distortion inside Audiokit? I want to add that and randomized tape crackles and ...
1
vote
1answer
196 views
AM modulated signal not centered at carrier frequency [closed]
I am trying to modulate the signal bl_msg_time (this is a speech signal) using DSB-SC modulation however the signal doesn't appear centered at the carrier frequency....
2
votes
1answer
442 views
Plotting the discrete time signal
Consider the following analog signal
$$x(t) = 2 \sin(100\pi t)$$
The signal $x(t)$ is sampled with a sampling rate $F_s=50\textrm{Hz}$. Determine the discrete time signal. Plot the discrete time ...
4
votes
3answers
396 views
Going from digital to analog filters
I've been learning about digital signal processing for some time, and I understand the principles in the digital world, as well as the conversion of continuous filters in the s-domain to digital ...
0
votes
1answer
78 views
Separate Complicated Signal into Exponential Components
This morning, I asked a similar question about separating simple signals - with constant frequency - into exponential components. User @AndreasH suggested that a hilbert transform can do this as ...
1
vote
2answers
2k views
Relation between Normal Phase Shift of a wave and Phase Modulation
I am little confused with the Phase Modulation and the phase of a sine wave. I get the phase modulated wave from the google images as below:
Phase modulation has the form:
$$PM(t)=A_c \cos\big(2\pi ...
1
vote
4answers
295 views
Signal and Space/Time
I have been reading a couple of definitions on signal such as:
Any quantity measurable through time over space or any higher
dimension can be taken as a signal.
And this,
In the physical ...
1
vote
3answers
733 views
Applying Nyquist theorem to digital vs. analog audio quality
I had a recent conversation with a friend about analog vs. digital recordings. He shared his opinion that music recorded by analog techniques is of superior sound quality to music recorded by digital ...
1
vote
1answer
341 views
Two-sided impulse response and its inverse in real life
Dear StackExchange gurus,
I would like to pose this question from a practical standpoint rather than a theoretical one, although perhaps some context in the latter might come useful.
Real-life ...
0
votes
1answer
39 views
What is full AM used for?
What are some applications where full AM is used nowadays? Is it used at all considering the fact that it is less power-efficient than, say, AM with suppressed carrier?
0
votes
1answer
183 views
How is multiplexing on FM signals performed? [closed]
How does multiplexing differ from FM signals to AM signals. If both FM and AM shift the message signal in frequency, then is there a difference between multiplexing for FM or AM signal?
0
votes
1answer
181 views
Given a noise-free channel with limited bandwidth, why is the channel capacity infinite? [duplicate]
In the Shannon Hartley theorem, if N = 0 but B is limited, the theorem tells us that C is infinite. Why is this intuitively true?
If bandwidth is limited, I can only post so many pulses per second ...
1
vote
2answers
672 views
Nyquist frequency and DC
Im studying the DSP book by Steven W. Smith. On page 41 he covers the Nyquist frequency. He makes up an example by writing the following.
... consider an analog signal composed of frequencies ...
1
vote
3answers
849 views
FIR analog low-pass filter?
Is there a way to construct FIR analog low-pass filter? (By this, I believe I am asking for no-pole analog low-pass filter, in terms of Laplace transform.)
2
votes
2answers
20k views
What is the difference between continuous, discrete, analog and digital signal?
It's my first time studying DSP and I've faced a problem finding a convenient definition.
Are the following definitions correct? And if so why there are some resources defining it in other terms such ...
0
votes
1answer
846 views
Low-pass elliptic filter design: equation for calculating required minimum order
In this paper on page 4 (or in slide page, 23), it describes the equation for calculating the minimum required order for elliptic filter for design specification. However, it says it is only the ...
0
votes
1answer
381 views
Is calculus background a must for learn DSP? [closed]
I'm beginner in DSP and in the literature some Authors suggest Analog (Continuous) Signal Processing a prerequisite for learn DSP. But it demands calculus background, that I do not have. Is calculus ...
1
vote
2answers
830 views
Calculation of actual analog input from bipolar ADC's output
I have a $14$-$\textrm{bit}$ ADC which can take $-10\textrm{ V}$ to $10\textrm{ V}$ as input. So, $0$ to $16383$ (digital) represents the voltage from $-10$ to $10$. If I want to get the actual ...
1
vote
3answers
221 views
Linearizing digital-analog converters
I'm looking at ways to improve the effective resolution of DACs. It seems that element mismatch (i.e. integral non-linearity) is the main contributor to distortion in modern DACs. Apart from ...
2
votes
1answer
353 views
Can we determine if a filter is butterworth or chebyshev from its physical topology?
Can all analog filters be classified as Bessel, Elliptic, Butterworth or Chebyshev?
Given a physical ladder topology of several stages of {L, C or LC} in {series or parallel}, is it possible to ...
