A Polar Coding With a Q-Section NBC Property for Managing Phase Ambiguity and PAPR in Multi-Carrier Communications

For an orthogonal frequency division multiplexing (OFDM) communication system which requires channel estimation for each sub-carrier without using pilot signals, there may exist the problem of phase ambiguity. By extending the conventional concept of noncoherent block coding (NBC), we propose a
$Q$
-section polar code that has the NBC property in such a way that each codeword is divided into
$Q$
sections and reversing the code bits in some sections results in another codeword which is encoded by the same desired message. The polar coded OFDM with a
$Q$
-section NBC property enables us to solve the problem of phase ambiguity that exists in each sub-carrier. In addition, the
$Q$
-section NBC property also enables us to employ the multiple-candidate method for reducing the peak-to-average-power ratio (PAPR).