Rectangular pulse octave There are three parameters that define a rectangular pulse: its height A, 4:03 • How to generate unit step, ramp, impulse and rectangular pulse for continuous signals in Matlab Rohit Salgotra 582 subscribers Subscribed The document describes an experiment involving signal processing using MATLAB/Octave, focusing on the generation and convolution of unit step and rectangular pulse signals. RectangularWaveform. For a rectangular pulse, the duration of the transmitted pulse and the processed echo are effectively the same Aug 28, 2025 · clear all; close all; x = -: 0. Generate a 50 kHz Gaussian RF pulse with 60% bandwidth radar_3_pulse_compression. Example: % Calculate the total energy of the output y (t)total_energy = A^2 * T; Nbits = 1e4; % number of bits (increase for better accuracy)Ns = 8; % samples per symbol Nbits = 1e4; % number of bits (increase for better accuracy)Ns = 8; % samples per symbol Nbits = 1e4; % number of bits (increase for better accuracy)Ns = 8; % samples per symbol Periodic Rectangular Pulse This example generates a pulse train using the default rectangular pulse of unit width. This MATLAB function performs rectangular pulse shaping on X and returns Y, increasing the sample rate of X by repeating each sample nsamp times. For the discussion, we will assume rectangular pulse shaping, the channel Compute the rectangular pulse function at coordinates –2, –1, 0, 1, and 2 with specified rising and falling edge at –1 and 1. Dec 4, 2024 · 7 8 9 % Rectangular Pulse t = -5: 0. The interpolation stays within the the time range of the delayed pulse. Example: Compute the rectangular pulse function at coordinates –2, –1, 0, 1, and 2 with specified rising and falling edge at –1 and 1. A smaller α creates a Tukey window with a steeper top, larger transition band, and better stop-band attenuation. (You could easily find tutorial or even many of Java application from internet). 0))11 Functions and Scripts ¶ Complicated Octave programs can often be simplified by defining functions. A rectangular pulse is defined by its duty cycle (the ratio of the width of the rectangle to its period), and by the delay of the pulse. Integrate-and-dump can also be used in fiber optics and in spread-spectrum communication systems such as CDMA (code division multiple access) applications. e. Jul 28, 2017 · Why is the difference and why ifft of samples taken from a sinc function will not produce an exact rectangular pulse but with ripples close to the edge while ifft(fft(v)) will exactly reproduce the original rectangular pulse: Matched Filter maximizes the peak-signal to mean noise ratio For rectangular pulse, matched filter is a simple pass band filter Aug 14, 2024 · It would be clearer if the original signal had only one rectangular pulse, but the presence of two pulses confuses me. sinc The sinc function is defined by sinc t = {sin π t π t t ≠ 0, 1 t = 0. If duty is specified, it is the percentage of time the square wave is "on". Jun 4, 2024 · Introduction to the 555 Timer IC and PWM The 555 timer is one of the most popular and versatile integrated circuits (ICs) of all time. It has very high side-lobes and is hard to recreate while sampling and reconstructing a signal. 5,1,5, centered at x=0. Most popular window functions are similar bell-shaped curves. Aug 25, 2025 · N_fft = 512; % Choose a power of 2 for efficiency, greater than or equal to length (x) Aug 25, 2025 · N_fft = 512; % Choose a power of 2 for efficiency, greater than or equal to length (x) Jun 16, 2011 · Is there a way to create a rectangular pulse with finite rise time in Simulink? I found the "Ideal Rectangular Pulse Filter" in the Communications Blockset. For the rest, consider this. 2s is generated. 7)), it should ``roll off'' at approximately 6 dB per octave (since ). How to Create Rectangular Pulse Waveforms To create a rectangular pulse waveform, use phased. Jul 23, 2024 · A = 1; tau = 2; t_range = -5:0. However, if I try to replicate that, what I get is a single peak at the signal frequency, and then a Jul 18, 2017 · You say you're using "no pulse shaping"; does that mean you're using rectangular pulses? Also, if you have 100 samples per symbol and no noise, then an easy way to draw a simple diagram would be running plot(s(1:300)); hold on; plot(s(301:600)); plot(s(601:900)) in octave or Matlab. The receiver structure is also called as matched filter. However, its use in space communication is still relatively new. Feb 2, 2024 · Comments Please sign up or log in to contribute to the discussion. * ( (x - 3) > = 0 & (x - 3) <= 2); % Equivalent to f (x-3) This MATLAB function generates a square wave with period 2π for the elements of the time array t. In audio work, we more typically plot the window transform magnitude on a decibel (dB) scale: Since the DTFT of the rectangular window approximates the sinc function, it should “roll off” at approximately 6 dB per octave, as verified in the log-log plot below: Aug 29, 2024 · Fs = 1; % Sampling frequency (since our n is discrete)frequencies = linspace (0, Fs, length (n)); Apr 22, 2008 · However, in typical transmission schemes, we do not hear of pulse shaping using sinc () filters. Was the second pulse ignored? Why do we start at -3/2 Ti and not -Ti? Why did the distance between two rectangles become equal to the rectangle's width? A popular window function, the Hann window. Apr 7, 2020 · I want to generate a periodic square wave (Signal/Pulse) in Octave/Matlab with the following properties: Amplitude of 0. A rectangular pulse refers to a pulse signal with a constant amplitude and a specific duration, characterized by a square shape in the time domain and a sinc function in the frequency domain. Functions can be defined directly on the command line during interactive Octave sessions, or in external files, and can be called just like built-in functions. By default, linear interpolation is used for generating delays. 5; % Duty cycle (fraction of the period the pulse is 'on This demonstration calculates and plots the magnitude and phase of the Fourier coefficients for a rectangular pulse train signal. This rectangular pulse has area (height·width) of one. I would like to generate the signal at 5khz with a duration of 0. on time * 100 duty cycle = ------------------ on time + off time See also: cos, sawtooth, sin, tripuls. Rectangular pulse A rectangular pulse with abrupt transitions is a natural choice for eliminating ISI. 05 Hz. Simulation discussed. After demodulation, the complex envelope of x (t) is the real-valued rectangular pulse a (t) of duration τ seconds. May 16, 2020 · In this video I have explained Impulse Signal with waveform and mathematical equationUnit Step Signals with Waveform and mathematical equationUnit Ramp Signa Implementing an integrate-and-dump operation or a windowed integrator. 3. May 13, 2025 · an anonymous user · May 13, 2025 Octave Run Fork function f = rect (width) t = -width:0. OCTAVE The Octave Knob sets the frequency of Oscillator A in organ-style steps: 32', 16', 8', and 4'. If n is larger than the dimension along which the FFT is calculated, then x is resized and padded with zeros. Such a sharp cutoff in the time domain (that steep wall) means automatically that the signal is practically unbounded in the frequency domain. Periodic Ambiguity Function with Delay and Doppler Output Plot the periodic ambiguity function of a rectangular pulse waveform for one period. So to start with a basic example, let's take a rectangular pulse with width 0. conv_t = 0: length (conv_signal) -1; subplot (2, 1, 1); stem (t, rect_pulse, 'r', 'LineWidth', 2); title ('Original Rectangular Pulse'); xlabel ('Time'); ylabel ('Amplitude'); subplot (2, 1, 2); 1. No further info is given. I've been able to evaluate the FFT but I'm not sure if the phase is correct because there are some tilt The pulse/rectangular wave includes four selectable widths: 50, 30, 15, and 8 percent duty cycle, giving you options from square wave to progressively more narrow pulses for richer harmonic variation. Figure 3. Developed in 1970 by Hans Camenzind at Signetics, the 555 timer can be used to create a variety of timing and pulse generation circuits. In Oct 1, 2018 · Key focus: Rectangular pulse shaping with abrupt transitions eliminates intersymbol interference, but it has infinitely extending frequency response. The sinc function is the continuous inverse Fourier transform of a rectangular pulse of width 2 π and unit height. Spectrum Analysis Windows In spectrum analysis of naturally occurring audio signals, we nearly always analyze a short segment of a signal, rather than the whole signal. clear; pkg load signal numberofsinewaves = 10; frequency = 1000; amplitude = 1; samplingrate = (1/frequency)/1000; Apr 12, 2017 · Memristor Experiments Included in This Tutorial knowm_mr_pulse – Rectangular Pulse with positive incremental pulse amplitude from 250mV to 1V with 250mV steps knowm_mr_pulse_neg – Rectangular Pulse with negative incremental pulse amplitude from -250mV to -1V with -250mV steps The sinc function computes the mathematical sinc function for an input vector or matrix x. The gain factor is a sinusoid of frequency 0. Function File: y = rectpuls (t) ¶ Function File: y = rectpuls (t, w) ¶ Generate a rectangular pulse over the interval [- w /2, w /2), sampled at times t. Designing the pulse shape is important Discover how to master the rectangular pulse function matlab with our concise guide. Note the pulse compression exhibited in the autocorrelation sequence of the linear FM pulse. Modulation with Pulse Shaping and Filtering Examples Rectangular Pulse Shaping Rectangular pulse shaping repeats each output from the modulator a fixed number of times to create an upsampled signal. Predict the bandwidth for both the baseband and modulated signals, with bandwidth defined as the frequency of the first null. 6: Roll-off of the rectangular-window Fourier transform. This is verified in the log-log plot of Fig. sawtooth Generates a sawtooth wave of period ‘2 * pi’ with limits ‘+1/-1’ for the elements of T. Viewed as a function of time, or space, the sinc function is the inverse Fourier transform of the rectangular pulse in frequency centered at zero, with width 2 π and unit height: Oct 28, 2025 · figure (3); plot (t1, a7); gridon; axis (-10 10 -2 2); xlable ('time'); ylable ('magnitude'); title ('rectangular pulse'); Output (Run the program to view its output) As α approaches 1, the Tukey window itself approaches a rectangular window. May 8, 2009 · In the post on transmit pulse shaping filter, we had discussed pulse shaping using rectangular and sinc. The width of rectangular pulse is w = 0. pulstran(t,d,p) Aug 10, 2012 · I am trying to generate a train of rectangular pulses. Otherwise, if n is smaller than the dimension along which the FFT is calculated, then Nov 26, 2019 · I'm trying to find a link between the Fourier-Transformation of aperiodic Signals and the FFT of them. radar_3b_pulse_compression. pulstran(t,d,p,fs) generates a pulse train that is the sum of multiple delayed interpolations of the prototype pulse in vector p, sampled at the rate fs, where p spans the time interval [0,(length(p)-1)/fs], and its samples are identically 0 outside this interval. Unlock its potential through clear examples and practical tips. Introduction The objective of this lab session is to introduce the basic concepts of pulse shaping, matched filter and pulse alignment. It is often used in digital signal processing and communication systems. Jai_07 · January 22, 2025 Octave Run Fork pulsewidth=4; T=10; dt=0. In signal processing and statistics, a window function (also known as an apodization function or tapering function[1]) is a mathematical function that is zero-valued outside of some chosen interval. Use of the RRC filtering (i. What is Pulse Width Modulation Jun 9, 2017 · I'm trying to plot the graph of the phase of the Fourier transform of a 2D rectangular pulse. Aug 29, 2025 · jaswanththommandru123 · August 29, 2025 Octave Run Fork clear all; close all; clc; %======== Rectangular pulse =========================== t = -3:0. m illustrates range resolution gain of rectangular pulse versus LFM pulse compression - two close targets are detected with LFM while not with rectangular pulse for the same pulse duration. Jul 21, 2024 · A = 1; tau = 2; t_range = -5:0. This will plot three slices of three symbols each on top of each other. 01:5; rect_pulse = A * (abs (t_range) <= tau/2); figure; subplot (2,1,1); plot (t_range, rect_pulse, 'b', 'LineWidth', 2); xlabel ('Time (t)'); ylabel ('Amplitude'); title ('Rectangular Pulse in Time Domain'); N = length (t_range); f_signal = fftshift (fft (rect_pulse, N)); freq_range = linspace (-pi, pi, N This MATLAB function returns a rectangular window of length L. Square waves symmetry . Perhaps most fundamentally, the ear similarly Fourier analyzes only a short segment of audio signals at a time (on the order of 10-20 ms worth). 3. The gauspuls function generates a Gaussian-modulated sinusoidal pulse with a specified time, center frequency, and fractional bandwidth. 5* (sign (t + (width/2)) - sign (t - (width/2))); plot (t,y) title ("Rectangular Pulse") grid on; f = y; end Output Question: Question 1 (4 points): Using Matlab to plot rectangular pulse and its Fourier transform signal. 1:10 a7=rectpuls (t1/10) figure (4 This MATLAB function returns a continuous, aperiodic, unit-height rectangular pulse at the sample times indicated in array t, centered about t = 0. shanwavf Feb 3, 2024 · an anonymous user · February 03, 2024 Octave Run Fork t = -4:0. 10 (R2008b). One of its most useful applications is generating pulse width modulation (PWM) signals. 5 Hz, the signal length is 60 s, and the sample rate is 1 kHz. Linear Frequency Modulated Pulse Waveforms LFM pulse waveforms increase time-bandwidth product and improve target detection. In this post we will discuss about optimal receiver structure when pulse shaping is used at the transmitter. , pulse shaping) is adopted in commercial communications, such as cellular technology, and used extensively. Dec 8, 2021 · The main lobe becomes narrower with the increase in the width of the rectangular pulse. This is useful with the function pulstran for generating a series of pulses. In digital communication, the message in digital must be converted into an analog signal to be transmitted. I want the train to start at the origin (t=0) and would like to know how to do this using functions in Signal Processing Toolbox 6. It's kind of a rectangular pulse, Function File: s = square (t, duty) ¶ Function File: s = square (t) ¶ Generate a square wave of period 2 pi with limits +1/-1. Introduction to Function and Script Files Defining Functions Returning from a Feb 10, 2014 · This example show s how to generate widely used periodic and aperiodic waveforms, sequences (impulse, step, ramp), pulse trains in Matlab. 1,0. plot (f, abs (X_f), 'r', 'LineWidth', 2); xlabel ('Frequency (f)'); ylabel ('|X (f)|'); title ('Magnitude spectrum of rectangular pulse (CTFT)'); grid on; axis ( [-10 10 0 max (abs (X_f)) *1. The receiver often uses an integrate-and-dump operation when the transmitter uses an ideal rectangular-pulse model. 1:width; y = 0. no overshoot or other aberrations. Additionally, it demonstrates the convolution of two rectangular pulses and the subsequent Assuming a rectangular pulse shape, predict the baseband and modulated frequency spectrum for this signal (ie. The phase spectrum of the rectangular function is an odd function of the frequency (ω). Sep 22, 2017 · The Octave interpreter should now be configured to automatically execute the knowm_mr_pulse_j. In real systems, rectangular pulses are spectrally bounded via filtering before transmission which results in pulses with finite rise and decay time. Apr 14, 2008 · Brief Matlab/Octave script for observing the spectrum of a random BPSK modulated symbols with rectangular filtering and sinc shape filtering might be helpful to uderstand the concept further. This analytic expression corresponds to the continuous inverse Fourier transform of a rectangular pulse of width 2 π and height 1: This presentation briefly discusses application of the Root Raised Cosine (RRC) pulse shaping in the space telecommunication. The repetition frequency is 0. 5 Period of 0. Since the DTFT of the rectangular window approximates the sinc function (see (3. We have an analog periodic signal that consists of positive rectangular pulses. Assume the pulse repetition frequency (PRF) is 10. 01: 2; % Define rectangular pulse: f (x) = 1 for 0 <= x <= 2 f = (1). Package: signal Jan 27, 2023 · I would expect the FFT of a periodic pulse signal to look like a sinc function, like shown here. But that one gives inifite rise time, basically the same as if doing a pure rate transition. When the magnitude spectrum is positive, then the phase is zero and if the magnitude spectrum is negative, then the phase is $ (±\pi)$. 09s and then starting again. obtain a closed-form mathematical expression). Therefore, to perform a spectrum I am pretty sure that you would learn how to create a sequence of (sin () + cos ()) to approximate computer clock-like rectangular pulse. Question: A rectangular pulse whose width is between 1 and 10 sec I can't figure out how to declare this in MATLAB/octave online code. 01s, then nothing for 0. GNU Octave Pulsed Waveforms Rectangular Pulse Waveforms Simplest waveform has constant amplitude over pulse duration. If we take the limit as T→0, we get a pulse of infinite height, zero width, but still with an area of one; this is the unit impulse and we represent it by δ (t). Conversely, reducing the duration of a pulse improves the range resolution of the radar. 01:4 % Generate t values % Define the rectangular pulse function rec (t) rec_t= zeros (size (t)); % Initialize result as an array of zeros rec_t ( (t >= -2) & (t <= 2)) = 1; % Set elements to 1 where -2 <= t <= 2 % Plot the rectangular pulse function plot (t, rec_t, 'LineWidth', 2) xlabel ('t') ylabel ('rec (t)') title If instead of a function name you supply a pulse shape sampled at frequency Fs (default 1 Hz), an interpolated version of the pulse is added at each delay d. It includes code for plotting the unit step signal, a decaying exponential signal, and the results of their convolutions. This article discuss three types of waveforms: square waves, rectangular waves and pulsed waves, each with unique characteristics and uses. Aug 10, 2024 · I've been studying the autocorrelation function of a rectangular pulse train process, and I came across an interesting situation on this site link here where a time shift $\\tau$ was introduced. This conversion is done by the pulse shaping filter, which changes each symbol into a suitable analog pulse. This Demonstration illustrates the relationship between a rectangular pulse signal and its Fourier transform. The amplitude is 2 V, the width of each pulse is 2 ms and the period time is 4 times as large as the pulse width, ie 8 ms. 6. Stepped FM Pulse Waveforms Stepped frequency pulse waveforms increase time-bandwidth product and improve target Jun 6, 2023 · Why not conceptually begin by simply knowing that the FT of a rectangular pulse (one pulse of some duty cycle width) is a sinc () function based upon its width? This rectangular pulse then repeats at some interval, obviously. Because these inputs are not symbolic objects, you get floating-point results. Here are some statements that generate a unit impulse, a unit step, a unit ramp, and a unit parabola. This will possibly change as the crowding of the frequency an anonymous user · January 11, 2025 Octave Run Fork % Parameters T = 1; % Period of the pulse train D = 0. This is equivalent to an upsampled pulse-train of upsampling factor L. In this post, objective is to understand the motivation behind using raised cosine filtering for pulse shaping. 1s and amplitude Plot Autocorrelation Sequences of Rectangular and Linear FM Pulses This example shows how to plot zero-Doppler cuts of the autocorrelation sequences of rectangular and linear FM pulses of equal duration. The interpolation method defaults to linear, but it can be any interpolation method accepted by the function interp1. Since MATLAB® is a programming language, an endless variety of different signals is possible. * (x > = 0 & x <= 2); % Define delayed signal: f (x-3) f_delayed = (1). Question: Fourier series representation of periodic pulse train signal and filtering through LP filter. Otherwise, if n is smaller than the dimension along which the FFT is calculated Functions and Scripts (GNU Octave (version 10. Rather, pulse shaping using raised cosine filter is frequently used. AI generated definition based on: RF and Digital Signal Processing for Software-Defined Radio, 2009 Jul 22, 2014 · ) Generating an isolated rectangular pulse in Matlab: An isolated rectangular pulse of unit amplitude and width w (the factor T in equations above ) can be generated easily with the help of in-built function – rectpuls (t,w) command in Matlab. As an example, a unit amplitude rectangular pulse of duration T = 0. 1: 5; indicator = (t> = -2) & (t<= 2); plot (t, indicator, "LineWidth", 2); This MATLAB function returns a continuous, aperiodic, unit-height rectangular pulse at the sample times indicated in array t, centered about t = 0. 001:3; % Manual Signal Processing (GNU Octave)If called with two arguments, n is expected to be an integer specifying the number of elements of x to use, or an empty matrix to specify that its value should be ignored. Feb 10, 2015 · I want to generate a continous pulse in Matlab. Typically, window functions are symmetric around the middle of the interval, approach a The simplest smoothing algorithm is the rectangular boxcar or unweighted sliding-average smooth; it simply replaces each point in the signal with the average of m adjacent points, where m is a positive integer called the smooth width. 4)), which has an amplitude envelope proportional to (see (3. 2 s T = 0. We obtain real window transforms like this only for symmetric, zero-centered windows. Feb 13, 2023 · The spectral properties of a rectangular pulse are, to say the least, problematic. 5 So far I have this: T Aug 2, 2025 · an anonymous user · August 02, 2025 Octave Run Fork t=-20; 1:20 %----------------------rectangular pulse------------% t1=-10:0. 01:5; rect_pulse = A * (abs (t_range) <= tau/2); figure; subplot (2,1,1); plot (t_range, rect_pulse, 'b', 'LineWidth', 2); xlabel ('Time (t)'); ylabel ('Amplitude'); title ('Rectangular Pulse in Time Domain'); N = length (t_range); f_signal = fftshift (fft (rect_pulse, N)); freq_range = linspace (-pi, pi, N The Fourier transform of the rectangular pulse is real and its spectrum, a sinc function, is unbounded. m illustrates pulse compression with linear frequency modulation (LFM). This pulse is shown in the time domain and we wish to examine its spectrum so it must be broken down into i s individual frequency Linear Frequency Modulated Pulse Waveforms Benefits of Using Linear FM Pulse Waveform Increasing the duration of a transmitted pulse increases its energy and improves target detection capability. This is the case for a variety of reasons. A rectangular pulse is merely an extension of this principle, and by changing cs, both odd and even, we can plo ch ha form. Non-Sinusoidal Waveforms: Square, Rectangular and Pulsed Waveforms In electronic engineering, generating and shaping electrical waveforms are important tasks used in many fields including communication systems and digital electronics. m script, and write debug output to the Octave console output window. rectpuls Generate a rectangular pulse over the interval [-W/2,W/2), sampled at times T. 0 kHz and that the sampling frequency is a multiple of the PRF. Find the most general form of the impulse response of a filter matched to a rectangular pulse of duration and amplitude . The sinc function computes the mathematical sinc function for an input vector or matrix. The square wave is +1 for that portion of the time. 2]); legend ('Divyansh 102306182'); Mar 5, 2022 · Octave example for square wave creation Did you know square waves as we know them are generated by summing a series of sine waves? In this blog I will provide a little square wave example written in octave. Zero-Padding for Interpolating Spectral Displays Zero-Padding for Interpolating Spectral Peaks Zero-Phase Zero Padding Matlab/Octave fftshift utility Index Ranges for Zero-Phase Zero-Padding Summary Matlab/Octave fftshift utility Index Ranges for Zero-Phase Zero-Padding Summary Spectrum Analysis Windows The Rectangular Window Apr 28, 2025 · The full-wave simulations employ a time-domain simulation solver that supplies a broadband pulse signal to a discrete hexahedral-mesh representation of the device in question via a waveguide port, and utilizes a finite-difference time-domain approximation of Maxwell's equations to propagate the pulse through the model. Return the Doppler and delay values from the pambgfun function. 05,0. Thus, the rectangular-pulse train has an infinite har- monic spectrum weighted by a sinc function having ze- ros at multiples of the sampling rate Fs(because the original rectangularpulse was taken to be one sampling interval wide). Please show the plot that was done. 01; t=-T:dt:T; pulse=zeros (size (t)); pulse (abs (t)<= pulsewidth/2)=1; subplot (3,1,1); plot (t Note that a (t) represents an on-off rectangular amplitude modulation of the carrier frequency. GNU Octave: Signal ProcessingIf called with two arguments, n is expected to be an integer specifying the number of elements of x to use, or an empty matrix to specify that its value should be ignored. Sketch QPSK constellation which uses the phase values / 4, 3 / 4 and indicate bit-to-symbol assignment using Gray mapping (so that 2 adjacent symbols differ by 1 bit only). 02 seconds Average (Mittelwert) of 0. qbgwjre mbvxoh cjdbek qfdcm yqrbk octokjj gklw jbauc qwsxc rpb vsjdymn caaua sdxw jljki iyfsp