title: Improving performance of channel equalization in RSOA-based WDM-PON by QR decomposition.
abstract: In reflective semiconductor optical amplifier (RSOA)-based wavelength division multiplexed passive optical network (WDM-PON), the bit rate is limited by low modulation bandwidth of RSOAs. To overcome the limitation, we apply QR decomposition in channel equalizer (QR-CE) to achieve successive interference cancellation (SIC) for discrete Fourier transform spreading orthogonal frequency division multiplexing (DFT-S OFDM) signal. Using an RSOA with a 3-dB modulation bandwidth of only ~800 MHz, we experimentally demonstrate a 15.5-Gb/s over 20-km SSMF DFT-S OFDM transmission with QR-CE. The experimental results show that DFTS-OFDM with QR-CE attains much better BER performance than DFTS-OFDM and OFDM with conventional channel equalizers. The impacts of several parameters on QR-CE are investigated. It is found that 2 sub-bands in one OFDM symbol and 1 pilot in each sub-band are sufficient to achieve optimal performance and maintain the high spectral efficiency.
authors.forename: Xiang
authors.initials: X
authors.lastname: Li
authors.forename: Wen-De
authors.initials: WD
authors.lastname: Zhong
authors.forename: Arokiaswami
authors.initials: A
authors.lastname: Alphones
authors.forename: Changyuan
authors.initials: C
authors.lastname: Yu
authors.forename: Zhaowen
authors.initials: Z
authors.lastname: Xu