Contents
What is the need to reconstruct a signal?
In signal processing, reconstruction usually means the determination of an original continuous signal from a sequence of equally spaced samples. This article takes a generalized abstract mathematical approach to signal sampling and reconstruction.
What is the purpose of a reconstruction filter?
The filter used in a digital to analog converter that eliminates the stair-stepped waveforms created in the digital sampling process and restores frequency, amplitude, and phase of the original signal.
Why do we need sampling of signals?
To convert a signal from continuous time to discrete time, a process called sampling is used. The value of the signal is measured at certain intervals in time. If the signal contains high frequency components, we will need to sample at a higher rate to avoid losing information that is in the signal.
Can a signal be reconstructed from a sample?
If a signal is band limited and its samples are taken at sufficient rate then those samples uniquely specify the signal and the signal can be reconstructed from those samples. The condition in which this is possible is known as Nyquist sampling theorem and is derived below.
Why does the reconstructed signal go unreflected in PRMS?
While the loss of a tiny Q wave in the reconstructed signal essentially goes unreflected in PPRD or PRMS, the absence of a Q wave represents an essential loss from a diagnostic point of view when, for example, diagnosing myocardial infarction.
How does sampling and reconstruction of signal use aliasing?
It is a simple technique because the samples in the form of numerical codes, can be the input signal to a Digital to Analog converter, which is clocked to produce a new output signal with every clock pulse. This technique produces a signal which has a stair step shape that follows the original signal.
How is a continuous time signal is processed?
A continuous time signal can be processed by processing its samples through a discrete time system. For reconstructing the continuous time signal from its discrete time samples without any error, the signal should be sampled at a sufficient rate that is determined by the sampling theorem.