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Electrical Engineering

Design of a PD controller for a double integrator system

The block diagram of a control system is given in the attachment.The inner loop is positive feedback, i.e. Ks>0, and hence the system is unstable. Adding a P-D controller on the forward channel and a unity negative feedback, one can stabilize the system. Find: 1. The conditions of Kc and Tc to stabilize the system. 2. T

CMRR, RC-lag circuit, Bode plot, Open-loop midrange gain

4. A certain op-amp has an open-loop voltage gain of 100,000 and a common mode gain of 0.2. Determine the CMRR in dB. 5. Find the open loop gain and phase shift for an RC-lag circuit at the following frequencies: (i) 1 Hz (ii) 10 Hz (iii) 100 Hz (iv) 1000 Hz (v) 10000 Hz. Plot the curve of phase shift versus frequency curve i

Electrical Engineering: Op-Amp

1. Show that gain rolls-off at -6 dB/octave for a passive LP filter. 2. (a) Write down the expression for the frequency-dependent open-loop gain of an operational amplifier. Sketch the magnitude of the open-loop gain of an operational amplifier as a function of frequency. Explain what is meant by a `single-lag' response of an

Slew rate, CMRR, Bandwidth, Critical frequency, Closed-loop gain

Please refer to the attachment for the figures mentioned in these questions. 1. When a pulse is applied to an op-amp, the output goes from -40 V to +5 V in 0.6 microseconds. What is the slew rate? 2. A certain diff-amp (differential amplifier) has a differential voltage gain of 1500 and a common-mode gain of 0.5. Determine

Characteristics of a filter

A filter has the following characteristics: Attenuation = 3.0 dB from 0 Hz to 2 kHz. From 2 kHz to 20 kHz attenuation increases from 3 dB to 23 dB in a straight line when plotted on axes of power in decibels (vertical axis) against log frequency ( horizontal axis). a. Is this a low pass, high pass, band pass or band sto

A direct-to-home (QPSK) satellite television system uses a geostationary satellite in orbit above the equator. Some typical link parameters are determined including path loss over the link to Earth, the power received at the edge of the transmit beam, the noise power in the ground receiver, the CNR in clear sky conditions and the BER in rain conditions

A direct-to-home satellite television system uses a geostationary satellite in orbit above the equator at a longitude of 109 degrees west. The parameters of the satellite transmission are as follows: Transmit power 160 dBW Transmit antenna gain (edge of coverag

Baseband Digital Transmission

A baseband digital data link transmits polar binary NRZ current pulses at a rate of 1.0 Msps. The link uses ideal RRC filters with roll off factor r = 0.5. a. Calculate the bandwidth occupied by the baseband binary signal. b. If the available channel bandwidth is 0.5 MHz, which of these can be used to transmit the di

Square wave, Multiplier, Oscillator frequency

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

Bandwidth occupied by the QPSK signal, BER at the output of the receiver

A satellite communication link transmits a QPSK signal at a rate of 64 ksps. The transmitter and receiver have ideal RRC filters with alpha = 0.2. At the input to the QPSK demodulator in the receiver, the CNR is 19.0 dB under normal conditions (no rain in the link, known as clear air conditions). Assume an implementation mar

Examination of bit errors on a digital link

An underground twisted pair line is one mile long. The line is used to send a 1.50 Mbps signal as a polar binary NRZ voltage waveform. A logical 1 is transmitted as a +1.0 V pulse and a logical 0 is transmitted as a -1.0 V pulse. At the output of the receiver's sampling gate the pulses have peak amplitudes of +100 mV and -10

Op-Amps: cutoff frequency, input voltage, characteristics of the 741C

1. If the unity gain frequency is 5 MHz and the midband open-loop voltage gain is 200,000, what is the cutoff frequency? 2. An op amp has a voltage gain of 500,000. If the output voltage is 1V, what is the input voltage? 3. Name a few ICs other than op amps. 4. Above the cutoff frequency, what happens to the voltage gai

Twisted Pair Telephone Line: maximum symbol rate, bit rate

A twisted pair telephone line is equipped with an equalizer that ensures the line has a constant attenuation between 300 Hz and 3300 Hz, and linear phase shift with frequency. A carrier at a frequency of 1800 Hz is modulated with QAM so that digital data can be transmitted on the twisted pair. The transmitter and receiver have

Gaussian Distribution

Assume, I have a Gaussian Distribution given by N~(u0,var) where u0 is mean and var is variance by sampling 999 points. I used Maximum Likelihood to get the above parameters i.e. u0 and var. Now from these 999 points, I take one point out (lets call it i) and add a new point (lets call it j). What will the new mean and v

Analyzing a Square wave in terms of sin components

A. A signal generator outputs a unipolar square wave with a period of 0.50 ms. The output of the generator is passed through an ideal low pass filter that has a cut off frequency of 4.5 kHz, to a spectrum analyzer. What frequencies would be seen on the spectrum analyzer screen? b. The signal generator output in part (a)