Jinnan Zhang Xueguang Yuan Xiaomin Ren Yongqing Huang Yangan Zhang Minglun Zhang A Novel DWDM-PON Utilizing Downstream IRZ Signal for Upstream Data Re-modulation with High Extinction Ratio. 434-436 2009 CNSR http://dx.doi.org/10.1109/CNSR.2009.76 conf/cnsr/2009 db/conf/cnsr/cnsr2009.html#ZhangYRHZZ09