Real-Time Demonstration of 20-Gb/s QPSK Burst-Mode Digital Coherent Reception for PON Upstream under Clock Frequency Mismatch of 1.0 MHz. - Iiyama, Noriko; Fujiwara, Masamichi; Kanai, Takuya; Suzuki, Hiro; Kani, Junichi; Terada, Jun (2020)