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Can we get time limited and band-limited signal simultaneously Why?
A law of Fourier transformations says that if a signal is finite in time, its spectrum extends to infinite frequency, and if its bandwidth is finite, its duration is infinite in time. Clearly we cannot have a time-domain signal of infinite duration, so we can never have a truly band-limited signal.
What is meant by band limited function?
1. n. [Geophysics] A function or time series whose Fourier transform is restricted to a finite range of frequencies or wavelengths. See: band, frequency, wavelength.
What is a time limited signal?
Bandlimiting is the limiting of a signal’s frequency domain representation or spectral density to zero above a certain finite frequency. A band-limited signal is one whose Fourier transform or spectral density has bounded support.
Do frequencies add up?
You don’t really mean it in frequency domain[or in time domain]! Rick, you are mixing addition of two sinusoids (the concern of the question) with multiplication (not of interest in the question). Addition does not produce any new frequency components.
Is a time limited signal band limited?
In signal processing, there is a time-frequency duality. Band-limited signals have infinite time duration and time-limited signals have infinite bandwidth.
What kind of signal is corrupt by aliasing?
Recalling that aliasing can corrupt the signal of interest, consider a special class of band-limited signals known as bandpass signals. A bandpass signal is characterized by a bandwidth not bounded by zero at its lower end.
How is the sampling and aliasing effect used?
The signal consists either of a single tone or of two tones, whose frequencies are chosen by the user. The sampling frequency is also chosen by the user. All values are in Hz. In this experiment we focus on the aliasing effect. In a second experiment we shall study the reconstruction of a signal from its samples.
When is a signal said to be band limited?
A signal is said to be band-limited if the amplitude of its spectrum goes to zero for all frequencies beyond some threshold called the cutoff frequency. For one such signal, G (f) in Figure 1, we see that the spectrum is zero for frequencies above α. In that case, the value α is also the bandwidth (BW) for this baseband signal.
Can a bandpass signal permit a lower sampling frequency?
Consider a baseband and a bandpass signal, each with the same value of maximum frequency. The bandpass signal permits a lower sampling frequency only if the recovery method includes a bandpass filter that isolates the original signal spectrum (the white rectangles in Figure 5).