Performance of burst-mode receivers for optical digital pulse position modulation in passive optical network application

A DC coupled burst-mode receiver for digital pulse position modulation (DPPM) is proposed for the first time. An analysis of the potential performance benefits of using such a receiver configuration in the upstream of a passive optical network is given. An optical pre-amplifier is assumed. Bit error rate expressions are derived and the performance is evaluated in terms of sensitivity and threshold acquisition penalty. Results are compared with a DC-coupled on-off keyed non-return-to-zero burst-mode receiver, and it is seen that DPPM's continuous mode sensitivity advantage (about 8 dB for the optimal case) is only reduced to 7.7 dB when overhead preamble is restricted to 12 bits and 6 dB when restricted to 6 bits. Thus, if necessary, DPPM can almost recover its sensitivity advantage by a trade off with preamble length. As such DPPM can potentially offer an increase in optical network unit numbers by a factor of 4 or, alternatively, an increase in range of around 20 km.