OFDM With Index Modulation Using Coordinate Interleaving

Orthogonal frequency division multiplexing with index modulation (OFDM-IM), which uses the indices of the active subcarriers to transmit data, is a recently proposed multicarrier transmission technique. In this letter, we propose coordinate interleaved OFDM-IM (CI-OFDM-IM) by combining OFDM-IM and space-time block codes with coordinate interleaving. In this scheme, the real and imaginary parts of the data symbols are transmitted over different active subcarriers to achieve an additional diversity gain. The average bit error probability (ABEP) of the proposed scheme is derived and its superiority over the reference systems is shown via computer simulations.