Recently, orthogonal time frequency space modulation with index (OTFS-IM) has been proposed to improve the bit-error-rate (BER) performance of OTFS system. However, only some grids in OTFS-IM system are activated, resulting low spectral efficiency (SE). In order solve this problem, a new scheme called multiple-mode (MM-OTFS-IM) is paper. scheme, all activated transmit bits. Each grid subblock a...

This article introduces a novel frequency-shift chirp spread spectrum (FSCSS) system with index modulation (IM). By using combinations of orthogonal signals for message representation, the proposed FSCSS (FSCSS-IM) is very flexible to design and can achieve much higher data rates than conventional under same bandwidth. The presents optimal detection algorithms, both coherently noncoherently, FS...

This paper introduces a novel dimming method for Light Fidelity (LiFi) based on time-domain sample index modulation (TIM), called indexed (iDim). The aim is to provide wide brightness range, while maintaining high signal-to-noise ratio (SNR) performance and transmission rate. Direct current optical orthogonal frequency division multiplexing (DCO-OFDM) used line codes are presented. system exper...