Combinatorial pulse position modulation for power-efficient free-space laser communications

Dual-pulse pulse position modulation (DPPM) for deep-space optical communications: Performance and practicality analysis

“…The rate of the modulation, defined as the number of output symbols vs the incoming bits is given as M/ log 2 M = 2 m /m. (2) To improve the data rate and throughput, multi-pulse PPM (MPPM) [1], also known as combinatorial PPM [2], has been developed as an extension to the single-pulse PPM. Since two or more pulses are allowed to convey information in each M -slot symbol, there are potentially…”

“…Although the concept of MPPM dates back to the late eighties (e.g. [1], [2]), the scheme has recently received a revived interest, spurred in part by the ever increasing data rate demand of today's lunar and deep-space communication systems (which now target a downlink data rate of 600 Mbps to 1 Gbps), and in part by the emerging technology of visible light communication (in which MPPM can be used to, for example, simultaneously control brightness and communicate data [5]). …”

Coded multipulse pulse-position modulation for free-space optical communications

“…e.g. [3], [4], [5], [6], [2], [7], [8], [9]. It has been shown that although MPPM can potentially be two times more bandwidth efficient than PPM with the same power efficiency [3], considerable throughput gains are only present for high signal power and duty cycle w/n [4], [9].…”

“…As for the second question, we note that several coding schemes have been studied for MPPM. Analytical results for ReedSolomon coded MPPM were given in [4], [5], [10], [6]. Sato et al [6] also analyzed the performance of convolutional coded 2-pulse MPPM and investigated the effect of imperfect slot synchronization on the error rate performance.…”

Differential pulse-position modulation for power-efficient optical communication

“…Examples of modulation techniques derived from PPM are multiple PPM (MPPM) [6], combinatorial PPM (CPPM) [7], and overlapping PPM (OPPM) [8]. Differential PPM (DPPM) is a simple modification of PPM that can achieve improved power and/or bandwidth efficiency.…”