Spectral leakage, Electrical Engineering

Assignment Help:

This assignment is intended to provide an easier analysis of how windows work. Begin by looking at individual spectrum bins as affected by off-bin-centred frequency components with different windows.

A sine wave component of the test signal is bin-centred if it has an integer number of periods in the data segment being analyzed. This almost never happens without planning.

When the signal is periodic and an integer number of periods fill the acquisition time interval, the FFT turns out such that the signal frequency matches one of the FFT frequency bins. When the number of periods in the acquisition is not an integer, the endpoints are discontinuous. The result is the high side lobes seen in the un-windowed spectrum plot. This phenomenon is called Spectral Leakage.

Consider the case of a sampling rate of 1024 Hz being used to look at a 16 Hz. Clearly 16 is a divisor of 1024, but how many samples are needed to uniquely identify the component.

a) using different sample lengths as shown, produce the corresponding FFT of the signal, explaining your results.

b) Repeat this exercise for frequencies 16.5 Hz, 17.0 Hz & 17.5 Hz

It is now necessary to consider the effects of windowing the data set with a view to minimizing leakage effects of a non bin-centered signal on the spectra computed.

c) repeat parts a) & b) by applying windowing to the data sets.

This has been illustrated graphically below using von Hann (Hanning) & Hamming windows, although clearly other could be used.. Graphs are shown for 16 Hz and again for 16.5 Hz.


Related Discussions:- Spectral leakage

Evaluate the form factor, Evaluate the form factor: For the saw tooth ...

Evaluate the form factor: For the saw tooth wave illustrated in Figure, find out the form factor. Figure: Saw Tooth Wave Solution Time period of given wave i

Hybrid parameters, Hybrid parameters (or) h - parameters:- If the ...

Hybrid parameters (or) h - parameters:- If the input current that is denoted as i 1 and output Voltage that is denoted as V 2 are takes as independent variables, input v

Weighted-resistor converter, Q. WEIGHTED-RESISTOR CONVERTER? Figure sho...

Q. WEIGHTED-RESISTOR CONVERTER? Figure shows a 4-bit weighted-resistor D/A converter which includes a reference voltage source, a set of four electronically controlled switches

#speed control, explain speed control of dc motor

explain speed control of dc motor

Effective value for periodic waveforms, Q. With a direct current of I A, th...

Q. With a direct current of I A, the power expended as heat in a resistor of Ris constant, independent of time, and equal to I 2 R. Consider Problem and find in each case the effe

Configured the dual processor architecture, Configured dual processor archi...

Configured dual processor architecture  In centralized SPC, dual processor architecture can be configured to operate in following one of three modes: 1.  Standby mode: In

Principle of transistor phase shift oscillator, Q. Explain the principle of...

Q. Explain the principle of transistor phase shift oscillator? The phase shift oscillator consists of an inverting amplifier stage coupled to a three stage RC filter network. T

Commercial losses in electrical systems, Commercial Losses in Electrical Sy...

Commercial Losses in Electrical Systems Commercial losses are caused by pilferage, theft, defective meters, and errors in meter reading and in estimating un-metered supply of

Principles behind ecg monitoring, a) Provide pertinent summary of the basic...

a) Provide pertinent summary of the basic principles behind ECG monitoring b) Using MATLAB, provide plots of the "clean" and "noisy" ECG signals. Investigate the spectral es

Matlab magnetic field, i have an assignment related to magnetic field i ha...

i have an assignment related to magnetic field i have attached the( MRI assignment sheet)[1] please read it carefully in the assignment 2 methods to get the results - one by

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd