Explore BrainMass

Electrical Engineering

Finding a transfer function

The frequency response of a linear time invariant system has been measured and can be seen in the attachment file below. A feedback element with a transfer function, H(s), is to be chosen so that the system steady-state error to a unit step input is equal to 0.07. What is a suitable transfer function to achieve this? I am ha

Resistance of Headlights

A 24-volt automotive battery is connected to two headlights, such that the two loads are in parallel; each of the headlights is intended to be a 75-W load, however, a 100-W headlight is mistakenly installed. What is the resistance of each headlight, and total reistance seen by the battery?

Current for Three-Phase Loads

Two balanced, in parallel connected, three phase loads are fed by a three phase line with a certain impedance per phase. Parameters are given for each load, with the line energized at the sending end from a 60Hz, three-phase balanced voltage source with line to line voltage of 120*((3)^(1/2))*(V) rms. Given the phase voltage (

Network Planning, Link Budget, and Hata Model

A Potential client has asked you to predict the number of cells necessary to cover 100 square miles. The area the client wished to cover compromises 5 sq miles Urban, 25 sq miles, Suburban and the remainder rural. For urban areas the client can acquire 30 m towers, for Suburban 60 m and for rural 100 m Assume feeder lengths =

Communications Systems of Frequency Downconverters

A frequency downconverter is implemented using a square-law device as follows. The band-pass filter has a center frequency fi=|fc - ft| (also known as the intermediate frequency, IF). Assume that the message bandwidth of the input signal m(t) is equal to B Hz. a) Determine the smallest possible IF frequency, so that there

Wireless Communication

1. For an urban environment, at 1900MHz, what is the path loss between a base station at 40m height and a mobile at 1.6m height separated by a distance of 5 km? 2. TDMA has 416 frequencies in one of the cellular license bands. If a cellular operator designs a network with a 5/15 reuse pattern, how many frequencies per cell

Wireless Communication Systems

1. Assume a CDMA system has only 4 walsh codes. If the mobile is assigned W4 and receives a data stream of 11011010, what is the output? 2. What is the c/I for a network using a 7/21 reuse pattern? (consider only the closest 6 interferers and a propagation exponent of 3.5)

C++ Program - Min/Max Number

I started writing a program and need help. I need to be able to enter up to 15 numbers and output the minimum number, maximum number and the geometric mean. I have a program started, is there a way to shorten it? And I don't understand the geometric mean. Thank you for your help.

C++ Program Help

I am trying to make a program that will read a file from a disk and will take the first letter of each word and and make that into a sentence. Example: Can Always Talk == CAT I can get into the file, just can't make it work.

Fault Currents and Three Phase Faults

Please see the attached diagram for the specific parameters in finding the real, sub-transient fault current for a line to ground fault. The same process should be repeated in finding the three phase fault at the same point.

Programming Logic for Movie Collection

You want to produce a report of your movie collection. Which fields would you use, and which would be the data types of each of those fields? Create a flowchart and pseudo-code for generating a report that prints all of the movies, with all movies made by the same director on one page, as well as the number of movies by each


[A] The frequency response of a 2nd order LTI filter is H(e^jw)=(b0+b1e^-jw+b2*e^-2jw)/(1-a1*e^-jw-a2*e^-2jw) Assume b1=b2=0. In each case state whether the filter is highpass, lowpass or band pass and draw the pole/zero plot. i) a1=-1.8, a2=-.81 ii) a1=-1.27, a2=-.81 iii) a1=0,a2=-.81 iv) a1=1.27,a2=-.81 Explain th

First Order Controller Design

Given P = [(3e)^-10.03s] / [s/4 + 1], use the Inverse Nichols Chart to design a simple G(s) to achieve the following specifications. i) Zero steady state error to a step output disturbance. ii) |1/(1 + L)| <= -15dB, w <= 1 rad/s. iii) [1/(1 + L)| <= 3dB, Aw

Wireless Communication and Walsh Code Matrix

(a) Graph the theoretical number of users of a CDMA system with a data rate of 9.6 kbs and 14.4 kbs while varying the Voice activity factors from 10% - 100% (b) Create the Walsh code matrix for a W16. (c) For IS-95, on the forward link, list the Walsh code assigned to the various logical channels (hint: there are 64 Walsh code

Matlab: Rectangular Window or von Hann (Hanning) Window

Assume the signal consist of a sum of 3 sinusoids (sine functions, no phase delay). One sine is at 50hz, the second is at 60hz, and the third is at 75 Hz. The 50hz and 60hz sines have a peak magnitude of 1, the 75hz sine has a peak magnitude of .1. Assume the combined signal is sampled at 240hz, and 256 samples of the signal a

Transfer Function and Feedback Control System

An open loop transfer function of a certain unit feedback control system is described as below, where K is an adjustable gain (Proportional Controller) and G(s) is a process transfer function. 1. In the space provided (see attached), sketch a Root Locus plot of the closed loop system for positive Proportional Controller gain

Proportional-Integral-Derivative Control

Consider the block diagram in Figure Q2.1, describing a process under Proportional-Integral-Derivative control. 1. Is the system open loop stable? 2. Let Ki = 10. Use the Routh-Hurwitz criterion to find the range of Kd and Kp in terms of Kd so that closed loop stability is achieved. 3. Suppose that Ki = 10, Kd = 1, an

Control Systems with Complex Poles

Consider five different control systems, with descriptions below. Which system will have the slowest rise time? (see attached) System 1: Two complex poles at -10 -j5, -10 +j5; System 2: Two complex poles at -10 -j5, -10 +j5 and a zero at +2; System 3: Two real poles at -10, -3; System 4: Two complex poles at: -10 -j5, -10

Communications Systems

Please refer to the attached file. It may contain more than one-page. A PCM system with uniform quantization is used to transmit a speech signal. The bandwidth of the signal is equal to 6 KHz. At the receiver we require an SNR in the reconstructed signal equal to 40 dB. a) What is the minimum sampling rate for the speech

Transistor Saturation

For the circuit of the figure attached, determine the required values of Rd, R1 and R2 so that the transistor operates in the saturation region with Id=0.5mA and Vd=3V. The enhancement mode PMOS transistor has Vt=-1V and K=0.5mAV^-2. What is the largest value Rd can have while maintaining the transistor in saturation?

Block Diagram Reduction

First Problem: 1. Find TY/R. 2. Find TU/d Second Problem: a) Find TY/R for the following system.

Knowledge About Control Systems

Consider a transient response of a control system as shown in the attached figure. Choose which system description matches this response. a) DC gain 2, pole at -2, -3, -4. b) DC gain 2, pole at -1-j4.4, -1+j4.4. c) DC gain 1, pole at -1-j4.4, -1+j4.4. d) DC gain 1, pole at -10. e) DC gain 2, pole at -10, -2, zero at +5.

Proportional-Rate Feedback Control

Consider the block diagram in the attached figure Q3.1, describing the process under Proportional-Rate Feedback control. 1) Find a closed loop system transfer function in terms of controller gains, Kp, Kd. 2) Find the value gains Kp,Kd such that the resulting Percent Overshoot of the closed loop step response will be equal

Matched Filter Theory

Find the impulse response of a filter matched to the signal in the attached problem.

Control Systems - System Output

Please supply steps to correct answer: For a CLOSED LOOP unit feedback control system, if reference (R) is eqaul to 5 units, and forward path Gain (G) is equal to 10, then the system output (Y) must be: (a) 50 (b) 4.54 (c) 5 (d) 10/11 (e) 0.454

Compute the Transfer Equation

The questions are for the equation: y"(t) + 6y'(t) + 34y(t) = 2x'(t) + 11x(t) a) Compute the transfer equation Y(s)/X(s). b) Compute the response of the system to the input x(t)=e^(-2t) u(t) assuming no initial stored energy. c) Compute the response of the system to the input x(t)=4t^2 * e^(-6t) u(t).

Using the Ruth Hurwitz Criterion

Question: Find the values of k for the system in part a) and the values of alpha for part b). Please view the attachment file to see the full questions for parts a) and b).

Nyquist Analysis

Given the Bode plot of open loop L(s)=..., (i) Make a sketch of the Nyquist diagram and determine the stability of the closed loop system with negative feedback.(ii)If the system is unstable... (See attachment for full questions)