Dual-Polarized Index Modulation in Terrestrial THz Communication Systems
Terahertz (THz) communication offers extreme data rates for next generation communication systems, yet it suffers from severe path loss. Though multiple-input multiple-output communication technology is a promising solution to overcome this, it may bring an excessive hardware complexity. Hence, index modulation stands as an alternative to exploit the multiple antenna structure and to reduce the hardware complexity. In this paper, a THz system employing dual-polarized variable generalized spatial modulation (DP-VGSM) is proposed, and its performance is examined in terms of bit error rate under free space loss, absorption loss, α-μ fading, and pointing errors. The performance of DP-VGSM is compared to spatial modulation (SM), generalized SM (GSM), variable GSM (VGSM), and DP-GSM. Computer simulations demonstrate that dual-polarized systems provide a significant advantage over single-polarized systems by reducing the correlation between channels and that DP-VGSM outperforms others.