Maximum Data Rate and Error Performance Comparisons of SPAD Array Optical Receivers

Abstract

In this paper a novel photodiode (PD) for optical wireless communication (OWC) is introduced. The proposed receiver is single-photon avalanche diode (SPAD), which becomes popular recently due to its higher power efficiency and better timing resolution. The introduction of SPAD array further enhances the counting capacity. Firstly, detection statistics of single SPAD receiver is introduced briefly. More focus has then been put on SPAD array receivers, including detection statistics analysis and error performance evaluations among on-off keying (OOK), pulse-position modulation (PPM) and channel coded PPM systems. It is found that the maximum achievable data rate is observed by M-ary PPM systems with higher M value, at the cost of degraded spectral efficiency. The PPM system with higher M also shows better error performance for fixed incident source power. The main contributions of this work are the mathematical derivations and performance analysis of error probability in PPM systems and channel coded PPM systems, as well as maximum achievable data rate evaluations. It is proved that channel coded systems could improve the error performance to a large extent.