  Successive interference cancellation (SIC) is used to approach the achievable
information rates (AIRs) of joint detection and decoding for long-haul optical
fiber links. The AIRs of memoryless ring constellations are compared to those
of circularly symmetric complex Gaussian modulation for surrogate channel
models with correlated phase noise. Simulations are performed for 1000 km of
standard single-mode fiber with ideal Raman amplification. In this setup, 32
rings and 16 SIC-stages with Gaussian message-passing receivers achieve the AIR
peaks of previous work. The computational complexity scales in proportion to
the number of SIC-stages, where one stage has the complexity of separate
detection and decoding.
