Abstract: The complexity of the maximum likelihood (ML) detector of the generalized spatial modulation-media based modulation system is very high and exponentially grows with the number of active antennas. A low-complexity detection algorithm termed energy ordered-relaxation iteration method (EO-RIM) is proposed. First, the possible active transmit antenna combinations and corresponding mirror activation pattern combinations are sorted according to their signal energy, then a relaxation iterative method is performed to obtain corresponding modulated signals. According to a predefined threshold, the algorithm strikes a trade-off between complexity and performance. Simulations show that the bit error ratio performance of EO-RIM algorithm approaches that of ML detection algorithm and is comparable to that of the ordered block minimum mean squared error detection algorithm. The computational complexity of EO-RIM grows with the square of the number of active antennas, while ML detector has exponential complexity.

Key words: media based modulation, generalized spatial modulation, relaxation iteration, detection