The ARDF process during each time slot (TS). Here n is an odd number and 5≤n≤2L−1, L≥3. The solid blocks denote that the sending relays transmit the codewords using the best antenna. Dashed blocks denote that the listening relays receive signals using all the antennas, and each codeword within the dashed circle is an unknown codeword to be decoded. The horizontal and vertical arrows imply that a node receives the corresponding codewords from sending source and the sending relay, respectively.