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### How to use phase codes for modulating a pulse

I am working on phase codes (examples - Frank, P1, P2, Zadoff Chu) to generate minimum side-lobes on matched filtering. I considered a sinosoidal carrier wave at $45\textrm{ mHz}$, and phase modulated ...
The phase coefficients of a real, even input signals should all apparently be $0$ or a multiple of $\pi$. That's a property of the DFT I've learned about in the Audio Signal processing course on ...
I want to design a filter with a custom phase delay related to frequency. As frequency increases, phase delay should increase. The time delay as a function of frequency can be expressed as: $t_d = \... 1answer 66 views ### Phase synchronization in BPSK In BPSK for demodulation at the receiver end we do phase recovery between received wave and carrier wave. We can find the phase difference between the carrier and received waves using : PLL And ... 1answer 40 views ### Calculating phase response of filter with latency I have an LTI filter that I want to treat like a black box. It has a latency of 24 samples. This is what I'm doing (which works for a filter with no latency): Send unit impulse through my filter ... 0answers 17 views ### FFT in MATLAB: How can I find the phase angle? [duplicate] So, I'm doing a project in which I have to find the phase angle between the fundamental waves of a voltage and a current signal. I'm doing so by performing the FFT in both signals in MATLAB. ... 1answer 33 views ### Non-causal FIR. Is that possible? I know that a FIR (Finite Impulse Response) filter has the same quantity of poles than zeros. And I believe all the poles are at$z=0$. And a FIR filter is always stable, so it's ROC has to include ... 0answers 20 views ### All-pass filter I know that I can write an all-pass system as: $$H_{ap}(z) = \frac{z^{-1}-a^*}{1-az^{-1}}$$ because it has magnitude$1$(or magnitude = constant) And I can also write it like: $$H_{ap}(z) = \frac{1-... 1answer 52 views ### Transform linear-phase FIR to minimum-phase FIR Given a FIR filter (non-causal) with phase zero and real coefficients given by$$H(z) = \sum_{n=-M}^{M}h[n]z^{-n}$$with ripple \delta_2. How can I obtain a filter H_{{\rm min}}(z) of minimum ... 1answer 65 views ### Periodically-varying phase between transmitted sound and received sound I have a function that can find the phase difference between two signals, this function uses Hilbert transform to do so. Here is the python code for it ... 1answer 46 views ### Generalized linear-phase filter I know I can write the frequency response of a Generalized linear-phase system as:$$H(e^{j\omega}) = A(\omega) e^{-j\left(\alpha \omega - \beta\right)}$$where A(\omega) is real. I need to prove ... 0answers 19 views ### Practical advices for applying phase correlation in image registration task I'm using OpenCV to detect shift between 2 images, here is sample code (based on cv::phaseCorrelate function): ... 1answer 34 views ### Nyquist with only poles at the origin I need to solve this three exercises:$$G_1(s) = \frac{1}{s}G_2(s) = \frac{1}{s^2}G_3(s) = \frac{1}{s^3}$$This is what I did: For the single pole (1/s), magnitude of A is \infty ... 1answer 26 views ### Why does QAM use two cycles instead of one per byte? If you look at this image, you can see that you have 256 possible binary values by modulating the amplitude (the radius of the trigonometric circle) and the phase (the degrees) of the carrier. ... 0answers 34 views ### Calculating Phase Response for 2 microphones given the input I want to measure and compare the phase response of two identical microphones. To do this, I have a pressure chamber, which allows to apply the same pressure to both microphones. I apply a sweeped ... 1answer 68 views ### Decomposition of H(z) as maximum-phase, minimum-phase The frequency response is:$$H(z) = 2-7z^{-1}+7z^{-2}-2z^{-3}$$I see that it has 3 zeros: z_{01} = \frac 12, z_{02} = 2, and z_{03} = 1; and 3 poles in:$$z_x = 0$$Now, I have to write ... 1answer 42 views ### Maximum phase with the same magnitude response I'm trying to solve an exercise in a general way and I can't find if my answer is correct. Given this frequency response:$$H(z) = 4 + 2\sqrt2 z^{-1} + z^{-2}$$I need to find a frequency response ... 1answer 49 views ### The meaning of the sign in a phase difference Say I have 2 signals: A = 1kHz Sine B = 1kHz Sine, 30° lagging the first one. If I plot the FFT-Phase of these 2 waveforms, and get the Phase values at 1kHz, I would get: A = -90° B = -120° ... 1answer 118 views ### Signals cross-correlation I am trying to measure phase difference between two received waves which are recorded by two separate PC's (microphones). The two PC's starts recording at the same time, then I make a sine wave sound ... 2answers 165 views ### Phase invariant detection of low frequency spikes I am a physics graduate student studying a new physical device via simulations. Thanks to SE DSP, reading Lyon's Understanding DSP as suggested (not all the way through it yet though), and a bunch of ... 1answer 36 views ### Best way to implement variable phase shift on FPGA? I have an incoming digitally sampled sine wave pulse, so my FPGA has the ADC level from an I and Q channel. I want to be able to shift the phase by some arbitrary amount. What's the most efficient ... 1answer 17 views ### Relating phase shift to the ROL/ROR operations Is phase-shifting in continuous-time analogous to the rotate-left (ROL) and rotate-right (ROR) operations in discrete-time? 1answer 33 views ### How would Fourier and Cosine Transforms responds to summation of cosines with same frequency but different phases? For example, if I have two signals, \cos(2\pi ft+\frac\pi4)+\cos(2\pi ft+\frac\pi3), what would be different in both transforms (Fourier and cosine) how would the spectrum changes? And What would ... 0answers 32 views ### Finding phase of fundamental from autocorrelation I have some code, shown below that I have been using to find the fundamental of a guitar string. After this function is called, I go thru the real buffer and find the peak, whose location gives me ... 2answers 78 views ### How to plot magnitude and phase response by hand if I have the Transfer Function? I have the transfer function of the system, which is:$$H(z) = \frac{1-z^{-1}}{5(1+2z^{-1})}$$How do I sketch the magnitude and phase response? I'm sorry for the bad formatting, it's my first time ... 1answer 36 views ### Code for a wavelet based hilbert transform? [closed] I normally implement the Hilbert transform using the Fourier transform. I have noise related issues I want to solve. Does anybody have an (apodized) implementation of the Hilbert transform handy, ... 1answer 62 views ### How to shift a signal to the center of the frequency domain? Let's assume I have a 1024 x 1024 matrix that represents the spatial domain. After I perform a FFT and center the frequencies, I get the a signal that looks like the following in the frequency domain.... 1answer 29 views ### Reasoning Behind Additional Phase Shift in DPSK In MATLAB's Comm System Toolbox there is an option for 'Phase Rotation', defined as the phase difference between previous and current modulated symbols when the input is zero. This is the first time I'... 1answer 35 views ### Reducing standing waves with phase randomization Will constantly randomizing the phase of an audio signal, say a speaker in the corner of a square room, reduce standing waves (i.e. room modes) in the room? For example if you wanted to create a ... 1answer 100 views ### How to remove 50 Hz frequency noise from a PCM file? Are you kind to tell me the odds or the means by which should I grab a clean signal with the ~50 \mathrm{Hz} carrier removed using just programming? I managed to make a program in Visual-C that ... 2answers 101 views ### Strange step response In the figure there is represented a step response of a mechanical system. I created a step variation in the excitation of a DC generator. This lead to a step variation in the torque developed by that ... 3answers 92 views ### Continuous phase for phase delay calculus in FIR filters I would like to estimate the phase delay accurately for any random FIR filter. The definition of the phase delay is the continuous phase divided by the angular frequency (with a sign change). That ... 1answer 84 views ### What is the absolute phase and the relative phase, of a signal? I need to know what is the absolute phase and the relative phase, of a signal? and why these phases are important in the signal processing? 0answers 45 views ### Amplitude/phase recovery on noisy signal I have a noisy signal that has an ac component of fixed frequency but variable amplitude and phase. I'd like to recover the ac component. The signal (blue trace) is mostly smooth, but has a few ... 3answers 41 views ### Phase shifting a noisy signal I have a signal of the form s(t)=A(t) \sum \cos(\omega_i(t)t +\phi_0) + n(t), where n is gaussian noise. I can only read the signal+noise and thus can not separate them. I want to phase shift ... 0answers 30 views ### Obtaining a frequency response from other frequency responses I have loaded six impulses responses (1024 samples each in length) into Matlab, zero-padded the end of each with 1024 zeroes and taken 2048 point DFTs of each using Matlab’s built in ... 1answer 124 views ### Why does this reconstruction produce a phase shift from the original signal? After an FFT of a signal is done, it is plotted as in the image below, with the original signal is on the first subplot. Using the magnitude and phase data of each frequency, it's reconstructed, ... 1answer 69 views ### Help Understanding Time of Flight Phase Sanitization Algorithm I'm implementing the technique found in this paper: http://front.sjtu.edu.cn/~jinyh/gradCourse/Paper/Wireless/SpotFi%20Decimeter%20Level%20Localization%20Using%20WiFi.pdf to perform localization. I'... 2answers 153 views ### Extracting accurate phase and amplitude information from FFT with an arbitrary number of samples This is a followup question to one I asked earlier based on the chat after the answer given by @hotpaw2, and cross-posted from stackoverflow since it was suggested it is more relevant to DSP. I have a ... 0answers 24 views ### Ideas to implement phase shifter on 4DSP FPGA FC6301 I have an FPGA FC6301 and I need to implement a simple phase shifter using StellarIP. At the moment i'm using Fpga FC6301 with carrier FMC144 by 4DSP and I'm using the provided design named: ... 2answers 59 views ### Will decorrelating an audio signal help reduce interference patterns at low frequencies? In live sound it is common to have a left/right sub-speaker configuration, which will produce an strong interference pattern in the audience area based on listener/sub-speaker locations. If the left/... 0answers 36 views ### Average Asynchronous Resample Latency Given a sample frequence of 1 Hz and periodic events. The latency of an event is the time difference to the next sampling point. What is the average latency over infinitely many events? Events are ... 0answers 10 views ### Estimate gain and phase from measured input and output I have a measured output from a closed loop controlled complex system with a simple sinusoidal command input. How can I estimate the gain and phase between input and measured output? 1answer 15 views ### DAPSK bit assignment for the amplitude difference I am studying DAPSK(Differential amplitude phase shift keying) at the moment. I have a 64-DAPSK. We are using 4 concentric rings and 6 bits per symbol. The first two bits contain the information of ... 2answers 80 views ### How do I find the phase response of a filter from the filter equation? I am new to this forum. I have been teaching myself DSP for the last two years, so my experience and knowledge has a long way to go. I am trying to find the phase response of a specific filter that I ... 1answer 69 views ### Minimum Phase & maximum phase i have 2 questions: 1-If zeros on the unite circle that will be min or max phase?and this system has low-pass frequency response or not ? 2-Is the min phase has the shortest impulse response? 2answers 226 views ### The need for phase wrapping? I understand the need for phase unwrapping and the complexity behind it. But, I'm struggling to understand why the phase information gets wrapped between -\pi to \pi in the first place? 2answers 158 views ### How is the Leslie speaker simulated? What are Leslie speaker / "rotary" style of digital audio processors doing? I think a simple one would model: Delay between speaker and a pair (stereo) of microphones. The tonal change when the ... 1answer 66 views ### Phasor notation of a complex number with apparently non-constant radius I'm asked to find the phasor of this signal:$$ x_1[n] = 3\sin\left(\frac \pi7 n\right) + 4j\cos\left(\frac \pi7 n\right),\quad (0\le n \le 20) \,.$$The phasor is defined as:$$ G z_{0}^{n}= Ae^{... 1answer 37 views ### Phase spectrum:$\mathrm{arg}\mathcal{F}(\omega)$or$\mathrm{-arg}\mathcal{F}(\omega)\$?
Do we need minus or not? I need to extract phase spectrum from that thing $$f(x) = \frac{1}{2\pi}\int_{-\infty}^{\infty} e^{i\omega x}d\omega\int_{-\infty}^{\infty}f(t)e^{-i\omega t}dt$$ I can do it ...