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So non-sinousoidal tone pulses are okay like the distorted waveform in the picture. My favorite pulses are always made of a superposition of waves of various frequencies and amplitudes as a Fourier series.blue_leaf77 said:In terms of daily life, waves are something which are waving and are not necessarily periodic, e.g. (real) water waves, sound waves, and EM waves. Mathematically, waves are the solutions of the wave equation.
Pulses are usually used to describe a propagating disturbance but localized in space at a given instant of time. A train of pulses (rather than a train of waves) are actually a superposition of many waves, therefore it also satisfies the wave equation, and with regard to the above paragraph it can also be called a wave.
Yes, that's actually what I was talking about in the last sentence of my previous comment.Jon B said:My favorite pulses are always made of a superposition of waves of various frequencies and amplitudes as a Fourier series.
I don't know what you want to say there.Jon B said:So non-sinousoidal tone pulses are okay like the distorted waveform in the picture.
I was thinking about a comment about sinusoidal wave shape not being a pulse.blue_leaf77 said:Yes, that's actually what I was talking about in the last sentence of my previous comment.
I don't know what you want to say there.
As I have suggested before, that the term "pulse" is most commonly used to describe a propagating disturbance which is localized in space in a given instant of time. This is what I believe as what most people, in particular scientists or engineers working in a field relevant to this term, have in their mind. So, a pulse does not seem to have been well-defined to refer to a certain distinct physical phenomena, but it's a more convenient term to use to distinguish it from the continuous type of waves.Jon B said:I was thinking about a comment about sinusoidal wave shape not being a pulse.
What is it when a continuous sinusoidal wave never crosses zero reference so that there is a train of pulses that doesn't produce upper harmonics like a square pulse does?blue_leaf77 said:As I have suggested before, that the term "pulse" is most commonly used to describe a propagating disturbance which is localized in space in a given instant of time. This is what I believe as what most people, in particular scientists or engineers working in a field relevant to this term, have in their mind. So, a pulse does not seem to have been well-defined to refer to a certain distinct physical phenomena, but it's a more convenient term to use to distinguish it from the continuous type of waves.
Following this, a continuous stationary sinusoidal function wouldn't normally be called a pulse.
There is no sinusoidal wave which does not cross the zero reference.Jon B said:What is it when a continuous sinusoidal wave never crosses zero reference so that there is a train of pulses that doesn't produce upper harmonics like a square pulse does?
Could you possibly be thinking about something like ##y(t) = \cos(\omega_0 t)+1##? It might look like a sinusoidal function but it's actually not. Try to calculate the Fourier series coefficients for ##-\pi/\omega_0 < x < \pi/\omega_0##, the coefficients for sine terms vanish but those for the cosine do not. In particular, the series will contain other harmonics as the sinusoid component ##\omega_0## due to the constant term ##1##.Jon B said:Right. It is undulating dc that looks identical to a sine wave. Like a mass in motion on a spring. The anchor is the zero reference and the sinus motion is above zero. Electronic magic.
Sounds good to me.blue_leaf77 said:Could you possibly be thinking about something like ##y(t) = \cos(\omega_0 t)+1##? It might look like a sinusoidal function but it's actually not. Try to calculate the Fourier series coefficients for ##-\pi/\omega_0 < x < \pi/\omega_0##, the coefficients for sine terms vanish but those for the cosine do not. In particular, the series will contain other harmonics as the sinusoid component ##\omega_0## due to the constant term ##1##.
Pulses are disturbances or vibrations that travel through a medium, carrying energy without transporting matter. They can be described as a single, short burst of energy.
Waves are a type of disturbance that travel through a medium, such as air or water, carrying energy from one place to another. They can be described as a continuous oscillation or vibration.
Pulses and waves are both types of disturbances that travel through a medium, but they differ in their characteristics. Pulses are short and localized, while waves are continuous and can travel long distances.
Train waves are a type of wave that consists of a series of pulses that are closely spaced and have the same amplitude and wavelength. They are often used in communication systems, such as radio waves or Morse code signals.
Examples of pulses include a heartbeat, a clap, or a single sound wave. Examples of waves include ocean waves, sound waves, and light waves.