Research On Indoor Visible Light MIMO Wireless Communications Based On Space Shift Keying

Visible Light Communication (VLC) is a new technology in wireless communication. It is oneof the hottest areas in optical wireless communications research, as it can organically combinewireless communications and solid-state lighting technology. Traditional Multiple Input MultipleOutput（MIMO）technique in radio frequency (RF) communications can improve system capacityand provide high-speed communication, but has a high realization complexity. Space Shift Keying(SSK) has only one transmit-antenna activated for data transmission at any signaling time instance,which can completely avoid inter-channel interference (ICI) at the receiver side and reduces thecomplexity of the systems. It is a new spectral efficiency enhancing solution for MIMO technique.This paper has studied the SSK technique used in Indoor Visible Light MIMO WirelessCommunications. Firstly, the channel capacity of the indoor visible light MIMO wirelesscommunications has been analyzed and derived. The number of white LEDs and photo detectors(PD) and the layout of them in a room that can affect the channel capacity of the system wereinvestigated, and the analytical and simulation results of the channel capacity distribution in roomhave been given out. It illustrates that selecting these parameters properly can obtain a very gooddistribution of communication capacity.Secondly, the reliability and validity of the SSK-MIMO systems have been studied. Linkcongestion and alignment schemes have been proposed to enhance the reliability performance of thesystem. Compared with the Repetition Coding (RC) system, the results have been shown that theSSK-MIMO system is very suitable as low system complexity solutions.Finally, this paper presents a packet mapping scheme in SSK-MIMO system which canimprove the performance of indoor visible light MIMO systems. The bit-error ratio (BER) andsystem model of the packet mapping scheme in SSK-MIMO system have been studied, it hasshown that the new scheme can provide a good BER performance as the traditional SSK-MIMOsystem, but a higher spectral efficiency.