All-optical packet-switched routing based on pulse-position-modulated header

The paper presents a node architecture for an all-optical packet router where packet header address and the routing table formats are based on the pulse position modulation (PPM). A single bit-wise AND gate is used for correlation of a packet header address with the PPM based routing table (PPRT) entries, thus resulting in reduced processing time and system complexity. It is also shown that the proposed scheme offer unicast/multi-cast/broadcast transmitting capabilities. We show that the optical power of the correlated packet header address and the switched signal on-off contrast ratio largely depend on the switching window width and the timing offset of the PPM header address.