Title: High Throughput Probabilistic Shaping with Product Distribution Matching,
Abstract: Product distribution matching (PDM) is proposed to generate target
distributions over large alphabets by combining the output of several parallel
distribution matchers (DMs) with smaller output alphabets. The parallel
architecture of PDM enables low-complexity and high-throughput implementation.
PDM is used as a shaping device for probabilistic amplitude shaping (PAS). For
64-ASK and a spectral efficiency of 4.5 bits per channel use (bpcu), PDM is as
power efficient as a single full-fledged DM. It is shown how PDM enables PAS
for parallel channels present in multi-carrier systems like digital subscriber
line (DSL) and orthogonal frequency-division multiplexing (OFDM). The key
feature is that PDM shares the DMs for lower bit-levels among different
sub-carriers, which improves the power efficiency significantly. A
representative parallel channel example shows that PAS with PDM is 0.93 dB more
power efficient than conventional uniform signaling and PDM is 0.35 dB more
power efficient than individual per channel DMs.