| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce signal deterioration caused by a transmission distance difference. <P>SOLUTION: A CPU 38 determines a bias current and a pulse amplitude of a laser diode 50 which generates an uplink optical signal, in accordance with distance information from an OLT 10. The CPU 38 reads data in an uplink buffer 42 to a driving circuit 44 so as to output the uplink optical signal to an optical fiber 16-1 during a permitted transmission time slot. The driving circuit 44 converts an electric signal from the uplink buffer 42 into a driving current of the pulse amplitude instructed by the CPU 38. A bias current generating circuit 46 generates the bias current instructed by the CPU 38. An adder 48 adds the pulse electric signal from the driving circuit 44 to the bias current from the bias current generating circuit 46 and applies an addition result as a driving signal to the laser diode 50. <P>COPYRIGHT: (C)2008,JPO&INPIT |
