Compared with optical network-on-chip (ONoC) with single wavelength, ONoC adopting wavelength division multiplexing (WDM) technology possesses a very prominent advantage—higher bandwidth. Therefore, WDM-based ONoC has been considered one of the most promising ways to relieve the rapidly increasing traffic load in communication systems. A WDM-based router, as the core equipment of WDM-based ONoC, is influenced by crosstalk noise, especially the nonlinear crosstalk noise generated by the four-wave mixing effect. Thus, to explore the performance of the N-port nonblocking optical router using WDM, we propose a universal analytic model to analyze the transmission loss, crosstalk noise, optical signal-to-noise ratio (OSNR), and bit error ratio (BER). The research results show that crosstalk noise varies along with signals at different wavelengths in the same channel. For signals with the same wavelength, the noises generated in the different transmission paths are obviously different from each other. For research of transmission loss, OSNR, and BER, similar results can be obtained. Based on the eye diagrams, we can learn that crosstalk noise will cause signal distortion to a certain extent. With this model, capability of this kind of multiport optical router using WDM can be understood conveniently.
The optical network-on-chip (ONoC) using WDM is the most promising candidate in MPSoCs for their strengths of high communication bandwidth, high energy efficiency, high transmission speed, lower latency and power dissipation. However, when WDM is utilized, new crosstalk noises are introduced, especially the four-wave mixing (FWM) crosstalk noise. In this paper, we propose a general crosstalk noise analysis model for the N-port nonblocking optical router in ONoC using WDM. As a case study, the transmission loss, crosstalk noise, and optical signal-to-noise ratio (OSNR) of the five-, six-port routers with eight wavelengths are presented. The results show the average OSNR is different for the different wavelength signals transmitted in the both routers. For the same channel, the OSNR is different among the signals with different wavelengths. For the same wavelength signal, the OSNR of different channels is also distinct.
Crosstalk noise and transmission loss are two key elements in determining the performance of optical routers. We propose a universal method for crosstalk noise and transmission loss analysis for the N-port nonblocking optical router used in photonic networks-on-chip. Utilizing this method, we study the crosstalk noise and transmission loss for the five-, six-, seven-, and eight-port optical routers. We ascertain that the crosstalk noise and transmission loss are different for different input–output pairs. For the five-port optical router, the maximum crosstalk noise ranges from 0 to −7.07 dBm, and the transmission loss ranges from −9.05 to −0.51 dB. Furthermore, based on the crosstalk noise and transmission loss, we analyze optical signal-to-noise ratio (OSNR) and bit error ratio (BER) for the five-, six-, seven-, and eight-port nonblocking optical routers. As the number of ports increases, the minimum average OSNR decreases and the average BER increases. In addition, in order to present the performance of the routers more visually, a fiber-optic communications system is designed to simulate the transmission processes of the signals of the different paths of the routers in Optisystem. The results show that the power amplitude of the input signal is obviously higher than the corresponding output signal. With this method, we can easily evaluate the transmission loss, crosstalk noise, OSNR, and BER of high-radix nonblocking optical routers and conveniently study the performance of the N-port optical router.