List of top Electronics and Communication Engineering Questions

The output noise variance due to an 8-bit ADC of a first-order filter with \[ H(z) = \frac{1}{1 - 0.25z^{-1}} \] for the input signal with noise variance \( \sigma^2 \) is
The number of multipliers and delay elements required in the direct form II realization of \[ H(z) = \frac{1 + 0.5z^{-1} - 2z^{-2}}{1 + z^{-1} - 2z^{-2}} \]
The number 110000000.010.....000 represented in IEEE single precision format corresponds to the decimal number
Which of the following causal analog transfer functions is used to design causal IIR digital filter with transfer function? \[ H(z) = \frac{0.05z}{z-e^{-0.42}} + \frac{0.05z}{z-e^{-0.2}} \] Assume impulse invariance transformation with T = 0.1s.
If the data rate of delta modulator output is 43.2 kbps, for the input signal of 3.6 kHz, then the sampling rate used is equal to,
When mean optical power launched into an 8 km length of fiber is 12 \(\mu\)W, the mean optical power at the fiber output is 3 \(\mu\)W. Find the overall signal attenuation in dB
Which of the following statements is true about error detection techniques used on communications link?
A \(4 \times 1\) multiplexer is used to multiplex 3 signals \(\{A, B, C\}\) with highest frequency components \(\{250 \text{ Hz}, 100 \text{ Hz}, 600 \text{ Hz}\}\) respectively. Each channel is uniformly sampled at a constant rate with the help of a channel selector clock (\(F_{\text{sel}}\)). The input channels \(\{I_1, I_2, I_3, I_4\}\) of the multiplexer are connected to the signals as \(\{A, C, B, C\}\) respectively. What is the minimum value for \(F_{\text{sel}}\) in order to recover the signals from their samples?
Consider an air filled rectangular waveguide with a cross section of 5cm x 3cm. For this waveguide, the cut off frequency (in MHz) of \(TE_{21}\) mode is
Calculate the propagation constant \( \gamma \) for a conducting medium in which \(\sigma\) = 58 MS/m, \( \mu_r \) = 1 and f = 100 MHz.

Match the following: For 8086 microprocessor 

It is desired to mask the higher order bits (D7-D4) of the data bytes in register C. consider the following set of 8085 instruction,
(i) MOV A, C
ANI FOH
MOV C, A
HLT
(ii) MOV A, C
MVI B, FOH
ANA B
MOV C, A
HLT
(iii) MOV A, C
MVI B, 0FH
ANA B
MOV C, A
HLT
(iv) MOV A, C
ANI 0FH
MOV C, A
HLT

Which type of filter is shown in the figure? 

Choose the minimum number of op-amps required to implement the given expression. \[ V_o = \left[ 1 + \frac{R_2}{R_1} \right] V_1 - \frac{R_2}{R_1} V_2 \]

For the circuit shown in the Figure below, \(g_m\) of the transistor is 

Parameters of the transistor shown in the circuit below are $\beta=100$, $I_{Cq} = 1$ mA. 
Input resistance $R_i$ of the circuit is:

Consider the circuit shown in the below Figure and its load line characteristic. The x-intercept of the load line is 

Amplifier configuration shown in the below Figure is with MOSFETS M1, M2 connected respectively in a configuration given by 

A digital filter with impulse response \[ h[n] = 2^n u[n] \] will have a transfer function with a region of convergence
The signal to quantization noise ratio of an analog to digital converter having full scale range of ±1 volt for seven bit word length is 42dB. The approximate value of signal to quantization noise ratio for 9 bit word length is
Window function used in FIR realization,
The shape of the rectangular window function is changed to other function such as Hamming and Blackman window functions so that
The Modulating frequency in narrow band frequency modulation is increased from 10 kHz to 20 kHz. The bandwidth is
The new pole locations due to truncation of coefficient to 4 bit including sign bit in the cascade realization \[ H(z) = \frac{1}{(1-0.95z^{-1})(1-0.25z^{-1})} \]
The transfer function of first order high pass digital Butterworth filter that has 3dB cut off frequency \( \omega = 0.15\pi \) using bilinear transformation with T=1s