Open AccessIncreasing the minimum Euclidean distance of the complex quadrature spatial modulation
Author(s) -
Mohaisen Manar
Publication year - 2018
Publication title -
iet communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.355
H-Index - 62
eISSN - 1751-8636
pISSN - 1751-8628
DOI - 10.1049/iet-com.2017.1198
Subject(s) - quadrature amplitude modulation , transmitter , constellation diagram , euclidean distance , mathematics , quadrature (astronomy) , algorithm , antenna (radio) , qam , modulation (music) , computer science , telecommunications , bit error rate , topology (electrical circuits) , electronic engineering , channel (broadcasting) , artificial intelligence , acoustics , combinatorics , physics , decoding methods , engineering
Complex quadrature spatial modulation transmits two signal symbols at each channel use, each is drawn from a different constellation set. The indices of the antennas from which the symbols are transmitted carry information to the receiver. When both symbols are transmitted from the same antenna, the symbols resulting from the addition of the two signal symbols belong to the Minkowski sum of the original two constellation sets. Therefore, the size of the modulation set at the transmitter increases and the minimum distance between transmitted symbols is reduced, leading to degradation in the error performance. In this study, the authors propose to equip the transmitter with an additional antenna which is used to transmit the second signal symbol only when the information bits representing the antenna indices are identical. The design of the optimum modulation sets that maximise the Euclidean distance is also addressed. Furthermore, based on the probability of antenna use, they advise an antenna ranking algorithm that improves the performance. The simulation results show that the proposed scheme achieves a signal‐to‐noise ratio gain of 6.4 and 9.5 dB using 16 quadrature amplitude modulation and 16 phase‐shift keying, respectively.