An N-Port Universal Multimode Optical Router Supporting Mode-Division Multiplexing

Optical network-on-chip (ONoC) is based on optical interconnects and optical routers (ORs), which have obvious advantages in bandwidth and power consumption. Transmission capacity is a significant performance in ONoC architecture, which has to be fully considered during the design process. Relying on mode-division multiplexing (MDM) technology, the system capacity of optical interconnection is greatly improved compared to the traditional multiplexing technology. With the explosion in MDM technology, the optical router supporting MDM came into being. In this paper, we design a multimode optical router (MDM-OR) model and analyze its indicators. Above all, we propose a novel multimode switching element and design an N-port universal multimode optical router (MDM-OR) model. Secondly, we analyze the insertion loss model of different optical devices and the crosstalk noise model of N-port MDM-OR. On this basis, a multimode router structure of a single-mode five-port optical router is proposed. At the same time, we analyze the transmission loss, crosstalk noise, signal-to-noise radio (OSNR), and bit error rate (BER) of different input–output pairs by inputting the 1550 nm TE0, TE1, and TE2 modes to the router.

A Full-Duplex 5×5 Optical Router Based on a Hybrid Photonic-Plasmonic Switch

An optical router is an essential component of a photonic network-on-chip (PNoC). Normally, an optical router consists of traditional optical elements such as the micro-ring resonator (MRR) and the Mach-Zehnder interferometer (MZI). This type of router has many disadvantages, such as a large size, lack of thermal stability and low speed, although their manufacturing technologies are mature. In this paper, we propose a full duplex 5×5 optical router based on a hybrid photonic-plasmonic switch (HPPS). The HPPS has the advantages of compactness, thermal stability and high speed, which can effectively solve the problems of traditional optical routers. In this work, each optical communication link in the optical router is independent, and each optical communication link no longer shares the same switch, which avoids blocking between channels and achieves full-duplex communication. The modelling of the optical router using the HPPS is performed through MATLAB as well as by a finite-difference-time-domain (FDTD) simulation. The maximum and average insertion losses (ILs) of the router are 5.4 dB and 3.5 dB, respectively, and the router has a fast switching time (100 ps). The results show that this optical router has the advantages of low loss and low energy consumption and provides a 5×5 full-duplex optical router for the PNoC.

A Novel Algorithm for Routing Paths Selection in Mesh-Based Optical Networks-on-Chips

Optical networks-on-chips (ONoCs) is an effective and extensible on-chip communication technology, which has the characteristics of high bandwidth, low consumption, and low delay. In the design process of ONoCs, power loss is an important factor for limiting the scalability of ONoCs. Additionally, the optical signal-to-noise ratio (OSNR) is an index to measure the quality of ONoCs. Nowadays, the routing algorithm commonly used in ONoCs is the dimension-order routing algorithm, but the routing paths selected by the algorithm have high power loss and crosstalk noise. In this paper, we propose a 5×5 all-pass optical router model for two-dimensional (2-D) mesh-based ONoCs. Based on the general optical router model and the calculation models of power loss and crosstalk noise, a novel algorithm is proposed in ordder to select the routing paths with the minimum power loss. At the same time, it can ensure that the routing paths have the approximately optimal OSNR. Finally, we employ the Cygnus optical router to verify the proposed routing algorithm. The results show that the algorithm can effectively reduce the power loss and improve the OSNR in the case of network sizes of 5×5 and 6×6. With the increase of the optical network scale, the algorithm can perform better in reducing the power loss and raising the OSNR.

Crosstalk Analysis and Performance Evaluation for Torus-Based Optical Networks-on-Chip Using WDM

Insertion loss and crosstalk noise will influence network performance severely, especially in optical networks-on-chip (ONoCs) when wavelength division multiplexing (WDM) technology is employed. In this paper, an insertion loss and crosstalk analysis model for WDM-based torus ONoCs is proposed to evaluate the network performance. To demonstrate the feasibility of the proposed methods, numerical simulations of the WDM-based torus ONoCs with optimized crossbar and crux optical routers are presented, and the worst-case link and network scalability are also revealed. The numerical simulation results demonstrate that the scale of the WDM-based torus ONoCs with the crux optical router can reach 6 × 5 or 5 × 6 before the noise power exceeds the signal power, and the network scale is 5 × 4 in the worst case when the optimized crossbar router is employed. Additionally, the simulated results of OptiSystem reveal that WDM-based torus ONoCs have better signal transmission quality when using the crux optical router, which is consistent with previous numerical simulations. Furthermore, compared with the single-wavelength network, WDM-based ONoCs have a great performance improvement in end-to-end (ETE) delay and throughput according to the simulated results of OPNET. The proposed network analysis method provides a reliable theoretical basis and technical support for the design and performance optimization of ONoCs.