Research On Dual Loop Optical Buffer For Variable Length Packets

With the rapid development in fiber optical communication, optical communication network has become the basic platform in modern communication network. In the common network nodes, we should transfer optical signal to electronic signal, then process it. As it needs time for optic-electronic elements and electronic cross switch to transfer signal and process it, there is an electron speed "bottleneck" in the network node. In order to overcome the "bottleneck", we should directly switch and process the optical signal. That means we should develop the all-optical communication network. As the all-optical packet switch (OPS) network can switch and process signal much faster and use the network bandwidth more efficiently, OPS network is a good selection in the future's ultra-fast speed network.The packet-switch technology is a store and forward technology. It is one of the most important technologies to store and switch the optical signal in the optical field for the OPS network. All-optical buffer, as the key element in the OPS network, its specification such as packet loss rate and storage capacity and so on will directly affect the performance in OPS network.The innovations of this thesis on all-optical buffer are as follows:1 We analyze many fiber loop style all-optical buffer methods. A few could have buffer optical signal. They just limit their works to the study and discus on the storage phenomena. Because the length of packet stored in the buffer is limited by the length of the fiber ring and the ring is constant the packet stored in the buffer cannot vary. In the operating network protocols such as Ethernet and token ring, the length of the frames is varying depending on the data length. Many buffer methods being studied cannot match the need in a real network.2 We select double loops 3X3 coupler all-optical buffers as our study object in our lab, and research and discussion the relationship between the length of buffer ring and the length of packed.3 In order to store the variable frame length, we use double loops 3X3 coupler all-optical buffers as basic buffer unit and research the method that that made several BLOB work in serial. The method can solved the contradiction between storing varying data frame and fixed loop length. It makes a progress in the process of the all-optical buffer application.4 In the lab, we construct a two DLOB serial experiment system. We successfully stored a data frame in parallel and analyzed the fineness of data packet separate in detail.