Performance and equilibrium experiment of a multiband CAP modulation system in wireless optical communication.

Abstract Multiband carrierless amplitude and phase (MultiCAP) modulation is a modulation mode based on Carrierless Amplitude and Phase (CAP). To improve the capability of a short distance optical communication system for communication capacity and frequency band utilization, multiband CAP modulation technology is adopted. In this article, the diagram for MultiCAP modulation signal of signal-to-noise ratio and bit error rate was analyzed under the condition of Gamma–Gamma atmospheric turbulence channel model. The bit error rate of 4 the band CAP modulation system has been discussed under conditions of different intensity fluctuation variance and signal-to-noise ratio. The simulation results show that when the total bandwidth is constant, the larger the frequency band is, the lower bit error rate is. When the value of σ R 2 is small, the system error rate decreases with increasing signal-to-noise ratio. When the σ R 2 is larger, the system error rate decreases with decreasing σ R 2. The experimental results of atmospheric laser communication show that the receiver branch signal phase shift are well compensated and intersymbol interference is effectively suppressed after using MMA algorithm for equilibrium, and the bit error rate of each branch signal is decreased from 1 0 − 3 to 2. 4462 × 1 0 − 4. Consequently, the system transmission performances improve. [ABSTRACT FROM AUTHOR]