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
Twenty voice signals are to be multiplexed and transmitted over twisted pair. What is the bandwidth required (in bps) if synchronous time division multiplexing is used, along with the standard analog-to-digital sampling rate, and each sample is converted into an 8-bit value?
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
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
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
Compare a lumped element model of a lossless transmission line (single L and C) with the distributed model. Use the following values for the transmission line in this comparative analysis. Vg = 5 V Zg = 50 ohms L' = 100 nH/m C' = 100 pF/m ZLoad = 100 ohms For the lumped model, represent the entire l
Laplace transform, Fourier transform, Unit-pulse response, Impulse response, DTFT, Differential equation
Please see the attachment for all the questions with proper symbols/notations. 1. Compute the Laplace transform of e^(-10t)cos(3)u(t) . 2. Compute the z-transform of the discrete time signal defined by: x[n] = δ[n] + 5δ[n - 1] 3. Compute the inverse Laplace transform of X(s) = (s+2) / (s^2+7s+12) . 4.
Please walk me through these problems step by step. 1. Compute the Laplace transform of e^(-10t) = u(t). 2. Compute the inverse Laplace transform of: X(s) = (3s^2+2s+1) / (s^3+5s^2+8s+4) 3. Use Laplace transforms to compute the solution to the differential equation given in the attachment.
Write down an expression for the voltage waveform, and sketch the waveforms of the harmonic components.
An a.c. voltage, V, comprises of a fundamental voltage of 100 V rms at a frequency of 120 Hz, a 3rd harmonic which is 20% of the fundamental, a 5th harmonic which is 10% of the fundamental and at a phase angle of 1.2 radians lagging. (i) Write down an expression for the voltage waveform. (ii) Sketch the waveforms of the harm
Range of local oscillator frequencies, Image frequency, Receiver's sensitivity, Sensitivity and dynamic range, System output
1. A receiver tunes the HF band (3 to 30 MHz), utilizes up-conversion with an intermediate frequency of 40.525 MHz, and uses high-side injection. Calculate the required range of local oscillator frequencies. 2. An AM broadcast receiver's pre-selector has a total effective Q of 90 to a received signal at 1180 kHz and uses an I
Why is it necessary to include an implementation margin when estimating the BER expected in a real digital communications link?
A satellite communication link transmits a QPSK signal at a rate of 10 Msps. The transmitter and receiver have ideal RRC filters with roll-off factor r = 0.25. At the input to the QPSK demodulator in the receiver, the CNR is 18.5 dB under clear air conditions (no rain in the link). a. What is the bandwidth occupied by th
A digital communication system transmits binary data using polar NRZ pulses of current over a baseband link with a bandwidth of 20 kHz. The transmitter and receiver have ideal "Root Raised Cosine" (RRC) filters with roll off factor = 0.5. a. What is the minimum bandwidth that the link must provide to avoid generating IS
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
An audio signal is sampled, digitized and recorded on magnetic tape as a PCM signal. This process is analysed
An audio signal has a frequency range from 50 Hz to 20 kHz. The signal is sampled, digitized and recorded on magnetic tape as a PCM signal. a. Assuming that ideal filters are available, what is the lowest frequency at which the signal can be sampled and subsequently recovered in its analog form without distortion using a lo
A signal consists of rectangular pulses of duration 0.1 ms that arrive at a receiver at random intervals of time. What is the shape of the spectrum of the signal? What is the extent of the spectrum in the frequency domain? What is the unit that is applied to the magnitude of the spectrum?
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
A. A digital radio link operates at a frequency of 75 MHz and uses ideal RRC filters with roll off factor r = 0.2 in the transmitter and receiver. The modulation used on the link is BPSK and the bit rate is 100 kbps. The 75 MHz transmitter has an output power of 1.0 W. Calculate the bandwidth occupi
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
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
Signal to noise ratio, Resonant frequency, Percent modulation, Transmitted power, Harmonic distortion
1. A microwave system requires a +4-dBm audio level to provide 100% modulation. Determine the voltage level required if this is a 600 ohm audio system. 2. Determine the noise produced by a 500 ohm resistor at 26 degrees Celcius over a 2 MHz bandwidth. 3. Consider an amplifier with an output of 2 mV rms and noise 0.76 mV rms.
BPSK signals, Source of additive white Gaussian noise (AWGN) in a radio receiver, Bit error rate, Time between errors
A radio link sends BPSK signals to a receiver with a bit rate of 100 kbps. It is found that the output of a radio receiver when no signal is present is AWGN with a rms voltage of 1.0 V. a. What is the usual source of additive white Gaussian noise (AWGN) in a radio receiver? b. For what percentage of the time is the noi
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
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
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
A baseband link is equipped with an equalizer such that its operating bandwidth is 1.00 MHz. Over this bandwidth the attenuation is constant at 25 dB and the phase shift is linear with frequency. The link is used for the transmission of digital signals. The transmitter and receiver have ideal RRC filters with roll off factor
A digital radio link is designed to carry a T1 rate digital signal (1.544 Mbps). The transmitter and receiver have ideal RRC bandpass filters with roll off factor (r) = 0.2. a. What RF bandwidth must the radio link provide if the modulation is binary phase shift keying (BPSK)? b. The link is unchanged but the modu
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
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
Audio signal, Sampling frequency, Bit rate at the output of the ADC, Maximum bandwidth, Quantization SNR
An audio signal has a bandwidth that extends from 100 Hz to 10 kHz. The signal is sampled to create a PAM signal and then digitized by an analog to digital converter (ADC) that has 8 bits. The digital signal is transmitted as a bit stream to a distant location where it is converted to parallel words and input to a digital to a
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)