Let us consider a convolutional code with k=1, n=2, l=3. That is, in each step, one bit is read, a window of the last 3 bits is considered (including the current bit), and 2 coded bits are produced. Let the stream of bits be denoted by xi (index i goes over all bits in the message). When we read in each bit x[i], we compute two parity bits p[i] and q[i] as follows:
p[i] = x[i] + x[i-1] + x[i-2]
q[i] = x[i] + x[i-1]
For the first bit i=0, assume x[i-1] = x[i-2] = 0.
(a) What is the rate of this convolutional code?
(b) If the message = 1101, compute the coded bits using the convolutional code.
(c) If the message = 0110, compute the coded bits using the convolutional code.