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Electrical Engineering

Transistor Minority Densities and Current Density

FIGURE 2(b) represents the carrier densities in the three neutral regions of the transistor under active conditions. The base-emitter junction is forward-biased by 0.6 volts and the base collector junction is reverse biased by 1 volt. The biased minority carrier densities are a function of distance x from the junction interfa

Proper Bridge Rectifier for PSU

FIGURE 1(a) shows a power supply using a full-wave bridge rectifier circuit. The main supply is stepped down by the transformer T1 and the secondary voltage Vs rectified by the four diodes D1 -D4; diodes D1 and D3 conduct on one half cycle and D2 and D4 on the other. The diodes are provided in a single 4-pin bridge-rectifier pac

Murray Loop Test and Locating Faults

Hi there, Can anyone answer the following questions please? Q.1 (a) Using the Murray Loop test, determine the distance to an earth fault on one of the cores of a uniform three-core underground cable. Ra = 2 ohms, Rb = 1 ohm and the cable length is 300 m. (b) If the cable measurement is accurate to ±1% what length of

FM Radio RF Channels

a. Frequency modulation is regarded as a much preferred modulation method over DSB-LC AM for sound radio broadcasting. Give two reasons why FM is preferred over AM in sound radio broadcasting. b. Do either or both of the reasons you gave in part (a) above also apply to a point to point voice link using frequency modulatio

Demodulator for FM Stereo Signals

Multiplication of a carrier by a modulating signal generates an AM waveform known as DSB-SC, the waveform is v(t) DSB-SC = Ac cos W ct x Vm cos Wmt Where W = is the angular velocity a. Make a sketch of the DSB-SC waveform with Vm = 1 V and Ac = 10 V for a carrier frequency of 10 kHz and a modulating signal frequency

Peak frequency deviation and Carson's rule bandwidth

A baseband signal has a frequency range from 50 Hz to 15.0 kHz. The signal is transmitted using frequency modulation. The FM transmitter has a modulation constant of 100 kHz per volt. a. A 1 volt peak sine wave signal at a frequency of 5 kHz is applied to the modulation terminal of the FM transmitter. What is the peak f

Modulating Radio Frequency Carriers to Carry Digital Data

Digital radio transmission requires the use of a carrier wave which is modulated by the digital data. a. What are the three possible ways in which a radio frequency carrier can be modulated to carry digital data? b. Write down the equation for the occupied bandwidth of a digital band pass (radio) link that h

Parameter of the rectangular pulses has changed

A spectrum analyzer is connected to a signal that is known to consist of randomly occurring rectangular pulses. The vertical axis of the spectrum analyzer is calibrated in dBm. The spectrum analyzer has the following display: A continuous spectrum with magnitude 0 dBm at 0 Hz and zero magnitude at 2 kHz, 4 kHz, 6 kHz, 8 kHz..

Filter characteristics

A filter has the following characteristics: Attenuation is 0 dB from 0 Hz to 2.5 kHz. Phase angle decreases linearly with increasing frequency above 2.5 kHz. Above 5 kHz the filter has steadily increasing attenuation. At 10 kHz attenuation is 6 dB and at 20 kHz attenuation is 24 dB. a. Is this a low pass, high pas


(c) The diagram of FIGURE 2 shows a bi-directional opto coupler input interface circuit. When a supply voltage of 20 V is applied the LED carries a current and 2 V is dropped across it. Calculate the value of the LED current and the value of current through the 3 k? resistance. FIG. 2 Please refer to the attachment.

why developing software for wireless devices is challenging?

List and briefly describe the two (2) reasons given in your textbook for why developing software for wireless devices is challenging. Include and describe five (5) of the major software components associated with mobile computing in your response.

Locating Cable Faults - The Murray Fisher method

FIGURE 1 shows a Wheatstone Bridge connection used to determine the location of a fault on a cable in which two cores are of different cross-sectional area (the Murray Fisher method). Ignoring test lead resistance, show that: a) For the first reading position, the resistance to the fault, Rx, is given by Rx = Rb1 /

Model Building and Parameter Estimation

See the attached file. This problem refers to the model building and parameter estimation in the presence of noise. For full details, see the attachment. The task is to implement a simulation model that generates data (simulating real-world measurements), and then fit two types of models to these data. One of the models i

Finding the Error Patterns in a Code

The full problem is Consider a (5,2) linear block code C with generator matrix: G = [1 0 1 1 0; 0 1 0 1 1] 1. Determine the parity check matrix H of C; 2. How many error patterns of C; 3. How many errors can the code correct? 4. Construct the following table; 5. Use the table above to find the most likely codeword v,

Electrostatic field

A long metal cylinder with radius a is coaxial with, and entirely inside, an equally long metal tube with internal radius 2a and external radius 3a. The space between the cylinder and the tube is filled with an LIH dielectric material with relative permittivity a. This space is also permeated by a uniform free charge distributio

What is the total capacity of the disk?

Consider a two-platter disk with the following parameters: Number of heads = 4 (one head for each surface of the platters) Rotation speed = 7200 rpm Number of tracks on one side of the platter = 30 000 Number of sectors per track = 600 Number of bytes per sector = 512 bytes Seek time = one ms for every hundred tracks trave

Capacity, Data and Transfer Rates, Access Time of Disk Drive

A hard disk drive has 10 disks and 18 surfaces available for recording. Each surface is composed of 200 concentric tracks and the disks rotate at 7200 r.p.m. Each track is divided into 8 blocks of 256 32-bit words. There is one read/write head per surface and it is possible to read the 18 tracks of a given cylinder simultaneousl

Solve the following Inverse and Laplace transform problems.

Please show all the steps and working. 1. Complete the following inverse Laplace transforms: a) 1/(2s + 4) b) 5s/(16+s^2) c) 10/s^2 d) 4/(s-2)^2 + 16 e) (9s+ 23) /(s+2)(s+3) 2. Complete the following Laplace transforms: a) 20 b) 20sin(5t) c) 20exp(-5t) e) 20exp(-5t)cos(5t) f) 20t^2 Please see the attachment fo

absorption loss of shielding

A plane metal shield offers an absorption loss of 30 dB at a frequency of 10 kHz to normally incident radiated emission. (a) Determine the absorption loss at 10 kHz in a shield of five times the thickness. (b) Determine the absorption loss at 20 kHz in a shield of half the original thickness.

Bandpass Sallen and Key

Design a bandpass filter of 'Sallen and Key' topology and having the following characteristics fo = 3.3 kHz, Q = 2.2. : Verify your design by means of a Bode plot.

First Order Filter to a Step Input.

A) FIGURE 2 shows the response of a first-order filter to a step input. Estimate the half-power cut-off frequency of the filter and sketch its frequency and phase response. B) Select (with justification) from the op-amps listed in TABLE A those which are NOT suitable for use as the active component in the filter of (a) above.

Eigenfunctions and LTI systems

The eigenfunction property is only valid for LTI systems. Consider the cases of nonlinear and of time varying systems. a. A system represented by the following imput-output equation is nonlinear: y(t) = x^2(t) Let x(t) = e^(j*pi*t/4). Find the corresponding system output y(t). Does the eigenfunction property hold? Explain.

Quantize using MATLAB

This is what I have so far: EDU>> %Sampling, Quantizing, Coding EDU>> %Analog Signal EDU>> t= [0:0.025:1]; EDU>> %Sampled Signal EDU>> x= 0.8*cos(2*pi*t)+0.15; EDU>> Ts=0.025; n=length(t);n=0:N-1; EDU>> xs = 0.8*cos(2*pi*n*Ts); EDU>> hold on EDU>> plot (t,x); EDU>> hold on EDU>> %Quantized Signal EDU>> Q=2; EDU>>

Signal Processing

Signal Processing. The Z- Transform. See attachment Signal Processing. Inverse Z-transform and poles and zeros When finding the inverse Z-transform of functions with z^(-1) terms in the numerator, that fact that z^(-1) can be thought of as a delay operator can be used to simplify the computation. Consider. X(z)=(1-z^(-

Microwave line of sight link transmits signal a distance

(1) A microwave line of sight link transmits a 10.0 GHz signal a distance of 25 km across a river estuary. The transmitter delivers 2 W to the transmitting antenna. The antennas at each end of the link have a gain of 36 dB. The receiver has a noise bandwidth of 20 MHz with rms noise power of -120.0 dBW. The transmitter and

Calculating Path Loss, RF Power and Bit Rates

A microwave line of sight link transmits a 10.0 GHz signal a distance of 25 km across a river estuary. The transmitter delivers 2 W to the transmitting antenna. The antennas at each end of the link have a gain of 36 dB. The receiver has a noise bandwidth of 20 MHz with rms noise power of -120.0 dBW. The transmitter and receiver