Digital communication

12345
Across
  1. 3. Costas loop is a method for
  2. 4. The key circuit used in DPSK modulator is
Down
  1. 1. the order of …………matrix is (n- k)x n
  2. 2. In encoding, we use three levels: positive, zero and negative.
  3. 5. Which of the following gives maximum probability of error?