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Electrical Engineering

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

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

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?

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

8 x 8 JPEG Image

Consider the following 8x8 8-bits image: 26 25 30 30 37 37 37 37 7 28 29 30 37 37 37 37 6 9 31 28 37 37 37 37 4 5 10 30 37 37 37 37 9 9 9

Phasor Current

Hi, I need some assistance for the following question: Question: For the following circuit, find the phasor current. Please see attachment for circuit diagram.

System Modelling (Output: Density)

Two tanks are arranged as shown in the attachment. Salt and water are added into the first tank at rates {see attachment}. The tanks are well mixed and the salt dissolves completely. The flow between the two tanks depends on the pressure difference {see attachment}. The flow out of te second tank is given by {see attachment}. Bo

System Modelling - Output and State Differential Equation

See the attached file. Consider the ice-cream manufacture process shown in the attachment. The ice-cream is made up of the following ingredients: i) Liquid (cream, milk, water etc.) added at a rate r1 [kg/hr] and with a density p1 [kg/1]. ... {see attachment for more details} (a) Find a model for the process with heigh

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

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

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

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 are

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

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?