Wideband Mixed Signal Separation Based on Photonic Signal Processing

The growing needs for high-speed and secure communications create an increasing challenge to the contemporary framework of signal processing. The coexistence of multiple high-speed wireless communication systems generates wideband interference. To protect the security and especially the privacy of users’ communications requires stealth communication that hides and recovers private information against eavesdropping attacks. The major problem in interference management and stealth information recovery is to separate the signal of interest from wideband interference/noise. However, the increasing signal bandwidth presents a real challenge to existing capabilities in separating the mixed signal and results in unacceptable latency. The photonic circuit processes a signal in an analog way with a unanimous frequency response over GHz bandwidth. The digital processor measures the statistical patterns of the signals with sampling rate orders of magnitude smaller than the Nyquist frequency. Under-sampling the signals significantly reduces the workload of the digital processor while providing accurate control of the photonic circuit to perform the real-time signal separations. The wideband mixed signal separation, based on photonic signal processing is scalable to multiple stages with the performance of each stage accrued.

Dual Fano Resonances Induced by Rectangle-based Plasmonic Resonator for Refractive Index Nano-sensor

A tunable dual Fano-like plasmonic structure consisting of metal-insulator-metal (MIM), baffle and a rectangular cavity containing two identical rectangular metal blocks is obtained. Numerical simulation results show that there are dual Fano resonances in the transmission spectrum of the structure, which can be tuned by changing the geometric parameters of the structure. In addition, due to the apparent asymmetry of the Fano resonances, the system was developed as an effective refractive index sensor (RIS) with a sensitivity of 853 nm/RIU and figure of merit (FOM) of 1631. It is considered that this structure has important application value in high integrated photonic circuit.

Low-Cost 400 Gbps DR4 Silicon Photonics Transmitter for Short-Reach Datacenter Application

Targeting high-speed, low-cost, short-reach intra-datacenter connections, we designed and tested an integrated silicon photonic circuit as a transmitter engine. This engine can be packaged into an optical transceiver module which meets the QSFP-DD Form Factor, together with other electrical/optical components. We first present the design and performance of a high-speed silicon modulator, which had a 3-dB EO bandwidth of >40 GHz and an ER of >5 dB. We then incorporated the engine onto a test board and injected a 53.125 Gbaud PAM4 signal. Clear eye patterns were observed at the receiver with TDECQ ~3 dB for all four lanes.

Photonic Integrated Interrogator for Monitoring the Patient Condition during MRI Diagnosis

In this work, we discuss the idea and practical implementation of an integrated photonic circuit-based interrogator of fiber Bragg grating (FBG) sensors dedicated to monitoring the condition of the patients exposed to Magnetic Resonance Imaging (MRI) diagnosis. The presented solution is based on an Arrayed Waveguide Grating (AWG) demultiplexer fabricated in generic indium phosphide technology. We demonstrate the consecutive steps of development of the device from design to demonstrator version of the system with confirmed functionality of monitoring the respiratory rate of the patient. The results, compared to those obtained using commercially available bulk interrogator, confirmed both the general concept and proper operation of the device.