Homework 8

bandpass filter; notch filter

A _________________ can be made by passing a signal in series through a low-pass and a high-pass filter. A __________________ can be made by passing a signal in parallel through a low-pass and a high-pass filter and then summing the two outputs.

analog

An electrical circuit made of a capacitor and a resistor placed in series forms an electronic filter. This filter is ____________ .

A. The stopband attenuation cannot be accurately determined from this graph

Consider the stopband attenuation of the filter shown below. Choose the best answer. A. The stopband attenuation cannot be accurately determined from this graph B. The stopband attenuation is 0 dB C. The stopband attenuation is -infinity dB D. The stopband attenuation is zero

10

For a FIR filter, if the Input Spectrum (original signal) amplitude array is [10, 20, 10, 20, 20] and the Filter Spectrum amplitude array is [2, 2, 1, 0, 0]. On the Output Spectrum, what is the amplitude for the third sample?

-60

In the filter shown below, what is the stopband attenuation (in dB)?

600

In the filter shown below, what is the transition width (in Hz)?

bandpass filter

Suppose that white noise is used as the input to a filter. Upon examining the output, it is found that frequencies between 400-900 Hz remain and the rest have been attenuated. What shape of filter was used?

False

T or F: An Infinite Impulse Response (IIR) filter is analog (continuous), while a ​Finite Impulse Response (FIR) filter is digital (discrete).

False

T or F: In the time domain, filters are often described by visualizing the frequencies that are able to "pass" through them.

multiplication; FIR; multiply; add

The convolution theorem states that convolution in the time domain equals _______________ in the frequency domain. Therefore, if you convolve an input waveform with a _____ filter, the equivalent operation is to ___________ the spectra expressed in linear units or _________ the spectra expressed in decibels.

1,400

What is the bandwidth (in Hz) of the filter shown below?

3,800

What is the bandwidth (in Hz) of the filter shown below?

226.76

What is the delay in microseconds for a signal as it passes through a FIR filter if the filter length is 21 and the sampling rate is 44100 Hz? Please round to two decimal places. (M/2)/fs

2,200

What is the high-frequency cutoff (in Hz) of the filter shown below?

600

What is the low-frequency cutoff (in Hz) of the filter shown below?

A. An impulse and white noise are similar in the frequency domain.

Which of the following is true? A. An impulse and white noise are similar in the frequency domain. B. An impulse and white noise are similar in the time domain. C. An impulse and white noise are similar in both the time and frequency domains.