Question

In soft decision approach 0 represents

(a) Certainly one

(b) Certainly zero

(c) Very likely zero

(d) Could be either zero or one

I had been asked this question in an internship interview.

Question is from Shannon Hartley Theorem and Turbo Codes topic in section Channel Coding of Digital Communications

Answer 1

The correct option is (d) Could be either zero or one

For explanation: The decoder front end produces an integer for each bit in the data stream. This integer is the measure of how likely it is that the bit 0 or 1 and is called as soft bit. It ranges from -127 to 127. Here 0 represents ‘could be either zero or one’.