Polarization-Dependent Gain in SOA-Based Optical Multistage Interconnection Networks

Abstract

Abstract-The small polarization dependence (< 1 dB) of optical components becomes significant in optical multistage interconnection networks. The cumulative effect can ultimately limit physical layer scalability by changing the maximum number of internal nodes that optical packets can traverse error free. It is shown that for nodes based on commercial semiconductor optical amplifier (SOA) switches with polarization-dependent gains of less than 0.35 dB, the maximum number of cascaded nodes changes by as much as 20 nodes, depending on both the packet wavelength and its state of polarization. This deviation in the number of nodes could correspond to a 100-fold decrease in the number of interconnected ports of an optical interconnection network such as the data vortex. This dramatic effect is explained in terms of optical signal-to-noise ratio degradation due to accumulated amplified spontaneous emission noise originating from the SOA device in the node.Index Terms-Multistage interconnection networks (MINs), optical packet switching, polarization-sensitive devices, semiconductor optical amplifier (SOA).

On contention resolution in the data vortex optical interconnection network

“…The power penalty of an SOA-based switching node was measured in [22] to be lower than 0.8 dB. Finally, the use of polarization maintaining fiber is suggested in [23] as a means of mitigating the cumulative PDG effect.…”

Scalable SiPh-InP Hybrid Switch Based on Low-Loss Building Blocks for Lossless Operation

“…The ASE noise level and OSNR degradation are the main challenges in cascading the hybrid switches to realize a higher radix switch. Also, large gain from SOAs leads to non-linearity effects that degraded the payload integrity and increase the power penalty [9]. Furthermore, the sensitivity of the SOAs is limited (approximately to -20 dBm) [7].…”

The Data Vortex Optical Packet Switched Interconnection Network

“…Again using a recirculating loop test bed with polarization controllers (PCs), it has been shown that the maximum number of cascaded nodes varies by as much as 20 elements for SOA-based designs with PDG of less than 0.35 dB. This corresponds to a 100-fold decrease in the number of interconnected ports of an optical interconnection network such as the data vortex [14]. It hence becomes evident that, for larger network sizes, PDG compensation techniques are necessary to minimize the dramatic shift in performance.…”

“…A 12-port data vortex prototype was implemented and its routing performance investigated [12]. The scalability of the physical layer was analyzed and demonstrated in [13] and [14], and further experimental studies of the optical dynamic range and packet format flexibility were performed [15], [16]. Sources of signal degradation in the data vortex were investigated in [17] and [18], and data resynchronization and recovery was achieved using a source synchronous embedded clock in [19].…”