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Electrical Engineering

Voltage by volt-ohmmeter & EVM

A voltage of 500 V is impressed on a 150 ohm resistor. The impedance of the voltage source is 10 kΩ. Two meters are used to measure the voltage across the 150-kΩ resistor: a volt-ohmmeter with an internal impedance of 1000 Ω/V and an EVM with an impedance of 11 MΩ. Calculate the voltage indicated by each of

Approximation of Quarter Circle Using Bezier Curve

Determine the Bezier curve of order 3 that approximates a quarter circle centered at (0,0), (1,0), (0,1). a) Calculate the coordinate of the middle point on the Bezier curve and on the arc and compare them. b) Plot both curves.

Spectrum Limitations

(See attached file for full problem description) --- A signal x(t) of finite energy is applied to a square-law device whose output y(t) is given by y(t) = x2(t) The spectrum of x(t) is limited to the frequency interval -W ≤ f ≤ W. Show that the spectrum of y(t) is limited to -2W ≤ f ≤ 2W. (Hi

Design with Multiplexer

I need some help answering this question: (I am not sure what C is, but it might mean complement) Design a circuit using one 16 TO 1 multiplexer with W, X,Y,Z on the control inputs. Let w be the most significant bit and Z the least significant bit on the control inputs: The equation of the circuit is: F= (Y+Z)(CW+CX+WX)+Y

Drawing a state diagram and state table

How would a Moore Model be developed from this design (provided in the attachment)? Could you also provide the state diagram and state table? If you can, can you please give me a description of how you derived such design of the circuit?

Electrical Engineering - Root locus

(b) A particular system has the open loop transfer function: g(s) = (s+4)/((s+1)(s-2)) sketch the root locus for this system (c) The system is placed in a feedback control system as shown in Figure Q6. Determine the gain, k, which would result in marginal stability. Determine the frequency of oscillation which would res

Control Systems Specifications

Given P = 1/(s/3+1), obtain a second order model for T(Y/Di) (transfer of input disturbance to plant output with feedback) to satisfy the following regulating requirements for a step input disturbance of height 15 units. Estimate lamba from the shape of the response. (See attached file for full problem description).

J-K Flip-flops

Using negative edge triggered J-K flip-flops, design a 3-bit synchronous sequence generator to generate the following sequence: 0,1,3,6,0..... 1. Draw up a table showing the input requirements on the J & K terminals for the four possible changes of state at the output. The table should be headed: PRESENT Q, NEXT Q, INPUTS J

Complex impedance and phase angle

Refer to diagram in attached file. 1. Derive an expression for the complex impedance between terminals A&B referring to the reactances as Xc & XL. Express the answer in the form of (real part + j * imaginary part) 2. Calculate the phase angle of the current I relative to the voltage Vin for a source frequency of 3kHz(must

Wireless Networks Question

Please help with the following problem. Mobile IP was intended to work with legacy correspondent hosts and legacy applications. However, some advantages may be gained if correspondent hosts are aware of mobility in certain ways. a) If a correspondent host is able to do IP-in-IP decapsulation, it may be able to communicate

Calculating the Maximum Calling Rate

You have a bandwidth of 10 MHz (per direction) in a single-cell system and want to deploy a wireless telephone system. You have the following options: analog 30-kHz channels (as in AMPS), digital 30-kHz channels (each supporting 3 users as in IS-54), digital 200-kHz channels (each supporting 8 users as in GSM), or CDMA with 10-k

Wireless Networks Questions

You want to download a 5 Mbit file over a 10-Mbps Rayleigh fading channel in the 1800 MHz frequency band. You are traveling at 6 km/h and use 1000-bit packets. The fading margin of the channel is 20 dB. If any packet is received in error during the transfer, the operation is aborted. (a) What is the probability that you successf

Wireless Networks Questions: Mobile Communications

The signal transmitted by a Base Station has a power of 1 mW at a distance of 1 m from the transmitter. Measurements have shown that the propagation exponent for the path loss is n=3 up to a distance of 1 km and n=4 beyond that. For adequate signal quality, a signal to noise ratio of at least 15 dB is required. Find the maximum

PI Controller and Nyquist Analysis

(Complete problem with equations found in attachment). Problem 1 A very common industrial controller is the proportional and integral (PI) controller. It has a transfer function, , kp is the proportional gain, Ti is the "reset time" For an integrating process, P(s) = 2/s, investigate the positive root locus for

Wireless Network - Prorogation Delay

The attached 'power point' slide contains information (note most of the information may not be relevant but a few slides contain the relevant formulas) that should assist with solving the problem in the Word document (see attachments). Suppose propagation delay is alpha, Short Interframe Space (SIFS) is alpha, Distributed Int

Wireless Networks - Encoder Output

1) The figure attached shows the encoder for a ½ rate convolution code. Determine the encoder output produced by the message sequence 1011. Assume that the initial state of the encoder is zero. See attachment for image.

Speedup and Efficiency

Question: Given 100 processors for a computation with 5% of the code that cannot be paralleled, compute the speedup and efficiency.

Saturated NPN Transistor

A saturated npn transistor has a base to emitter applied voltage of 0.6V. The collector to emitter voltage is 0.2V. The collector current is 12mA. The beta value of the transistor is 30. What is the emitter current?

Important Information About RC Series Circuit

An RC series circuit has a voltage source of 10Vac, a resistor of 10ohms, and a capacitor with an impedance of -j10ohms. How do I find the magnitude and phase angle of the current flow through the capacitor?

Design a series controller

The process of a unity-feedback control system has the transfer function 100 Gp(s) = ------------------------ s^2 + 10 s + 100 Design a series controller (a PD, PI or PID) so that the following performance specifications are satisfied. Steady-state error due to a step i

Autocorrelation and Tao

I have a question from my ECE 302 class regarding the mean of a random process given a particular autocorrelation function in terms of tao. I know Variance=(mean-square)-(mean)^2 and I know that the (mean-square)=autocorrelation function with tao set to 0, but I don't know how to get the mean if I don't know the variance of

Transfer Function Analysis for a Unity Feedback System

For a unity feedback system with open-loop transfer function, G(s) = K(s+alpha)/(s^2 + 4s + 1): a) Find all values of alpha such that the system is stable for K = 2. b) If the unity feedback closes around this G(s) and an input is a unit step r(t) = 1u(t), what is the stead-state error, e_ss, as a function of alpha and K? c)

Thevenin Equivalent Voltage

A resistor, R, was connected to a circuit box as shown. The voltage, v, was measured. The resistor was changed, and the voltage was measured again. The results are shown in the table. Determine the Thevenin equivalent voltage vt of the circuit within the box. Determine the Thevenin equivalent resistance Rt of the circuit?

Linear Systems and Equilibrium Point

Consider the ping pong ball levitator shown in the attachment. Assume that a nozzle makes a cone of air with velocity V_air(h) = u(t) / (h + alpha)^2. u(t) is the opening of an air supply valve, h is the height above the nozzle and alpha is a constant. The drag force on the ball is f_up = c_d * A(v_air - v_ball)^2. "A" is the

Solving: Fourier Series

Compute the Fourier series coefficient of the periodic function shown in the figure(view attachment) and defined as: X(t) = A 0 <= t <= T/3 0 T/3 <= t < T