A spectrum analyzer is connected to an unknown signal. The spectrum analyzer displays the power level of signals in dBm vertically and frequency horizontally. The spectrum of the unknown signal creates the following display:
A continuous spectrum that is completely filled so no lines are visible.
The spectrum has a sin X / X (sinc X) shape. The spectrum has maximum power spectral density at 0 Hz and falls to zero at 2 kHz, 4 kHz, 6 kHz and other even kHz frequencies.

a. What is the input waveform?
b. Is the input signal periodic or non-periodic?
c. What is the pulse width?
d. If the spectrum suddenly changes to have zeroes at 5 kHz, 10 kHz, 15 kHz, etc, what is the new pulse width?

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(a)

The Sin(x)/x type waveform (also known as Sinc(x) function) in the frequency domain is charactristic of a stream of pulses. The zero crossing points (nulls) in the Sinc(x) = Sin(x)/x waveform occur at points denoted by

1/t, 2/t, 3/t.......n/t (n an integer ranging from 1 to infincity) where t represents the pulse width (time duration) of the pulses. In addition with the Sinc(x) function if there is any periodicity in the pulse stream (ie repeated data patterns) then this ...

Solution Summary

In this solution from a description of a Sinc function we back engineer the signal to its tiime domain representation to answerthe following

A spectrum analyzer is connected to an unknown signal. The spectrum analyzer displays the power level of signals in dBm vertically and frequency horizontally. The spectrum of the unknown signal creates the following display:
A continuous spectrum that is completely filled so no lines are visible.
The spectrum has a sin X / X (sinc X) shape. The spectrum has maximum power spectral density at 0 Hz and falls to zero at 2 kHz, 4 kHz, 6 kHz and other even kHz frequencies.

a. What is the input waveform?
b. Is the input signal periodic or non-periodic?
c. What is the pulse width?
d. If the spectrum suddenly changes to have zeroes at 5 kHz, 10 kHz, 15 kHz, etc, what is the new pulse width?

Please provide necessary explanations leading to the answer.
a. A square wave signal with voltage levels 0 volts and 2.0 volt at a frequency of 1.00 MHz
is multiplied by a sine wave at a frequency of 5.0 MHz. Which of the following frequencies are
present at the output of the multiplier - there may also

A spectrum analyzer is connected to an unknown signal. The spectrum analyzer displays the voltage level of signals in volts vertically and frequency horizontally. The spectrum of the unknown signal creates the following display:
A vertical line at a frequency of 50 kHz with a magnitude of 1.80 V
A vertical line at a fr

Laplace transforms enable interpretation and manipulation of different signals by viewing these signals as either timedomainsignals/pulse or else frequencydomain representations. A number of examples are presented in these solutions showing how such tranforms may be maniupluted to better understand circuit driving forces. A n

A waveform v(t) has a Fourier transform which extends over the range -F to +F in the frequencydomain. The square of the waveform v(t), that is, v(t) v(t), then has a Fourier transforms which extends over the range:
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Answers:
a) -F to +F
b) -2F to +2F
c) -3F to +3F
d) -4F to +

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List the output frequencies of all 3rd order (those near 15 GH

Imagine that a civilization in another planetary system is sending a radio signal toward Earth. As our planet moves in its orbit around the Sun, the wavelength of the signal we receive will change due to the Doppler effect. This give SETI scientists a way to distinguish stray signals of terrestrial origin (which will not show