Wednesday, October 15, 2014

Problem For The Day! 15 - Oct - 2014

A few samples of 11point DFT X[k] of a 11length signal are given by

X[0]=4, X[2]=1+j3, X[4]=2+j5 and X[6]=9j6.

The value of X[5] is _.

Tuesday, October 14, 2014

Problem For The Day! 14 - Oct - 2014

Let a discrete random process be defined as Y[n]=2X[n]4X[n1], where X[n] is a zero mean WSS process with auto-correlation function RX[k]={,0,12,1,12,0,}. The average power of the process Y[n] would be _.

Monday, October 13, 2014

Problem For The Day! 13 - Oct - 2014

Let x(t) be a time limited signal from t=1 to t=3. The signal given by y(t)=x(1t)+x(2t1)u(1t)
is time limited from

(A)  -1 to 1. (B)  -2 to 2. (C)  -2 to 1. (D)  -1 to 2.


Sunday, October 12, 2014

Saturday, October 11, 2014

Problem For The Day! - 11 - Oct - 2014


Let X1,X2 and X3 be three i.i.d. exponential distributed random variables with parameter λ=1. Let Y1=X1+X2, Y2=X1+X3 and Y3=X2+X3. The probability that {Y1>Y2>Y3} is

(A) 12 (B) 13 (C) 16 (D) 56

Friday, October 10, 2014

Problem For The Day! - 10 - Oct - 2014

Let x[n]={6,5,4,3,2,1} and h[n]={1,0,0,0,1,0}. Let y1[n] and y2[n] be 6point and 10point circular convolutions of x[n] and h[n]. The values of y1[2] and y2[2] respectively are

(A) 6,4 (B) 4,6 (C) 6,6 (D) 4,4.

Thursday, October 9, 2014

Problem For The Day! - 09 - Oct - 2014


The integral x(2t+1)δ(2t+1)dt
is same as

(A) x(2t+1)  (B) x(2t1) (C) 12x(0) (D) x(t)