Digital Notch filter

digital_notch_filter_frequency_phase_response

In some designs, it may be required to have a digital filter which attenuates a single frequency component with the rest of the frequencies pass through. Filtering out of the power line frequency of 50/60Hz [...]

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Bitwidth in CIC filter

moving_average_comb_integrator_freq_response

The previous article on Cascaded Integrator Comb (CIC) filter discussed the filter structure, the frequency response and it’s usage in upsampling and downsampling. This post will briefly go over the CIC filter, fixed point arithmetic [...]

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GATE-2012 ECE Q10 (networks)

Question 10 on networks from GATE (Graduate Aptitude Test in Engineering) 2012 Electronics and Communication Engineering paper. Q10. The average power delivered to an impedance  by a current  is (A) 44.2W (B) 50W (C) 62.5W [...]

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GATE-2012 ECE Q18 (signals)

Question 18 on signals from GATE (Graduate Aptitude Test in Engineering) 2012 Electronics and Communication Engineering paper. Q18. If , then the region of convergence (ROC) of its Z transform  in the z-plane will be (A)  [...]

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Migrated to Amazon EC2 instance (from shared hosting)

Being not too happy with the speed of the shared hosting, decided to move the blog to an Amazon Elastic Compute Cloud (Amazon EC2) instance.  Given this is a baby step, picked up a micro instance [...]

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GATE-2012 ECE Q28 (electromagnetics)

quarter_wave_matching_transformer

Question 28 on electromagnetics from GATE (Graduate Aptitude Test in Engineering) 2012 Electronics and Communication Engineering paper. Q28. A transmission line with a characteristic impedance of 100 is used to match a 50 section to a 200 section. If the matching [...]

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Image Rejection Ratio (IMRR) with transmit IQ gain/phase imbalance

iq_modulator_with_gain_phase_imbalance

The post on IQ imbalance in transmitter, briefly discussed the effect of amplitude and phase imbalance and also showed that IQ imbalance results in spectrum at the image frequency. In this article, we will quantify [...]

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GATE-2012 ECE Q15 (communication)

entropy_versus_probability

Question 15 on communication from GATE (Graduate Aptitude Test in Engineering) 2012 Electronics and Communication Engineering paper. Q15. A source alphabet consists of N symbols with the probability of the first two symbols being the [...]

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GATE-2012 ECE Q7 (digital)

Question 7 on digital from GATE (Graduate Aptitude Test in Engineering) 2012 Electronics and Communication Engineering paper. Q7. The output Y of a 2-bit comparator is logic 1 whenever the 2 bit input A is [...]

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GATE-2012 ECE Q13 (circuits)

voltage_clamper_peak_detector_circuit

Question 13 on analog electronics from GATE (Graduate Aptitude Test in Engineering) 2012 Electronics and Communication Engineering paper. Q13. The diodes and the capacitors in the circuit shown are ideal. The voltage  across the diode  is (A)  [...]

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GATE-2012 ECE Q34 (signals)

Question 34 on signals from GATE (Graduate Aptitude Test in Engineering) 2012 Electronics and Communication Engineering paper. Q34. Consider the differential equation  with  and  The numerical value of  is (A) -2 (B) -1 (C) 0 (D) [...]

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GATE-2012 ECE Q12 (math)

Question 12 on math from GATE (Graduate Aptitude Test in Engineering) 2012 Electronics and Communication Engineering paper. Q12. With initial condition  the solution of the differential equation,  is (A) (B) (C) (D) Solution From the product [...]

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GATE-2012 ECE Q11 (signals)

Question 11 on signals from GATE (Graduate Aptitude Test in Engineering) 2012 Electronics and Communication Engineering paper. Q11. The unilateral Laplace transform of is . The unilateral Laplace transform ofis (A)  (B)  (C)  (D)  Solution From [...]

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GATE-2012 ECE Q2 (communication)

power_spectral_density

Question 52 on communication from GATE (Graduate Aptitude Test in Engineering) 2012 Electronics and Communication Engineering paper. Q2. The power spectral density of a real process for positive frequencies is shown below. The values of  and , [...]

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