Solution of ECE 316 Test 1 Su08
1. Determine whether or not the systems with these frequency responses are causal and explain how you know. (a)
Hj
( )=1
e
j
ht =
(b)
( ) (t ) (t 1) h (t ) = 0 () ( )
j 40 f
, t<0
Causal
H f = rect f / 20 e
h
%ECE 316 HW1 Function for problem 6
function F = myProblem6Fun(x)
ind1 = 0;
x = zeros(1,4);
for ind1=0:3
x = x + [-1 + x(ind1);
x + x(ind1)*exp(j*ind1*(2*pi/4);
x + -2 + x(ind1)*exp(j*ind1*pi);
x + 1 + x(ind1)*exp(j*ind1*3*pi/2)];
end
function F = myProblem6FunJH(x)
k = 0;
F = [-1 + symsum(x*exp(j*k*0),k,0,3);
symsum(x*exp(j*k*2*pi/4),k,0,3);
-2 + symsum(x*exp(j*k*pi),k,0,3);
1 + symsum(x*exp(j*k*3*pi/2),k,0,3);]
Solution of ECE 316 Test 2 Su08
1. The signal x t = 5tri(t 1)
()
2
(t ) is sampled at a rate of 8
samples/second with the first sample (sample number 1) occurring at time t =0. (a) What is the numerical value of sample number 6? The signal is a p
%ECE 316 Problem 7
N1 = 2;
for ind1 = 1:4
if ind1 = 1
N = 5;
elseif ind1 = 2
N = 15;
elseif ind1 =3
N = 40;
elseif ind1 = 4
N = 80
end
k3 = (-2*N):1:(2*N);
y = ones(1,(4*N + 1);
for k = (-2*N):1:(2*N);
k2 = k + (2*N + 1);
check