For the first time, compared with common bulk PMOSFETs, single-event transient (SET) mechanism was researched in a novel SOI PMOSFETs using technology computer-aided design mixed-mode numerical (TCAD) simulations. The simulation results showed that, different from the common bulk CMOS technology, diffusion but not bipolar effect is the main mechanism in PMOSFETs fabricated in this novel SOI CMOS technology. The effects of buried oxide (BOX) layer and body tie on SET were also discussed for the PMOSFETs in this technology. The radiation hardened by design (RHBD) layout technique was proposed for further SET mitigation. All of the studies indicated that this novel SOI CMOS technology has the essential advantage for radiation hardened integrated circuit (IC) design.

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On many-core Network-on-Chips (NoCs), communication is on the critical path of system performance and contended synchronization requests may cause large performance penalty. Different from conventional algorithm-based approaches, the paper addresses the barrier synchronization problem from the angle of optimizing its communication performance and proposes cooperative communication as a means to achieve efficient and scalable all-to-all barrier synchronization on mesh-based many-core NoCs. With the cooperative communication, routers collaborate with one another to accomplish a fast barrier synchronization task. The cooperative communication is implemented in our router at low cost. Through comparative experiments, our approach evidently exhibits high efficiency and good scalability.

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Amplification of Brillouin scattering signal extends the measurement range and improves the signal-to-noise ratio of fiber-optic distributed Brillouin sensors. Here, we investigate the amplification effect of a 980-nm pump laser on Brillouin gain spectrum in an erbium-doped optical fiber. The Brillouin-scattered Stokes power increased exponentially with increasing pump power, exhibiting approximately 87% enhancement at 252 mW compared with the Stokes power obtained without the pump. This suggests that a more significant increase in the Stokes power is feasible with a higher-power 980-nm pump laser.

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We report an injection-locked 60 Gbit/s 64 QAM coherent transmission employing a laser diode (LD) based heterodyne demodulation circuit. The LDs for the transmitter and receiver were InP-based external cavity laser diodes (ECLDs) emitting at 1538.8 nm. By using an injection locking technique with locking range of 100 MHz, we achieved low phase noise carrier synchronization between the data and the local oscillator with a phase noise of 0.3 deg. As a result, a polarization-multiplexed 64 QAM data signal was successfully transmitted over 160 km with a spectral efficiency of 9 bit/s/Hz.

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This paper presents a design of thin and broadband non-magnetic metamaterial absorbers using circular loop shaped resistive frequency selective surfaces (FSS). A straightforward visual graphic representation analysis which extends the microwave impedance matching theory into wideband metamaterial absorbing structure design is carried out on the key parameters analysis of the absorbers. Absorbers with different layers are analyzed. Numerical computing results are in good agreement with the analyzed ones. The study shows that visual graphic representation analysis could greatly decrease the range of variable. The visualization method is simple and practicable to introduce the working principles of the wideband non-magnetic metamaterial absorbing structure and to derive the best-suited element for wideband absorption.

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The spectral characteristics of a 1.3-µm npn-AlGaInAs/InP transistor laser were studied under various collector–base voltages and emitter currents. The result shows that the peak wavelength shifts as a function of the output power resulting from voltage and current controls exhibited contrasting behavior under a continuous-wave operation.

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The voltage-frequency island (VFI) design paradigm has strong potential for achieving high energy efficiency in emerging communication centric many-core system-on-chip (SoC) technology called network-on-chip (NoC). In VFI design, each core is allocated into a suitable domain with different voltage and frequency considering the required workload. Most VFI NoC studies have focused on regular topologies. However, today’s diversified applications demand custom NoC topologies to accommodate heterogeneous many-core architectures. In this paper, we propose a low-power custom topology generation method for constructing VFI NoCs, which embraces irregular topologies. The main objective of this work is to minimize energy consumption and communication resources, hence improving communication efficiency.

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In this letter, a tunable optical receiver is demonstrated in standard 65-nm complementary metal-oxide-semiconductor technology for universal optical interconnects. With supply voltage scaling, a 3-dB bandwidth, a power efficiency, and a noise performance can be optimized according to the target bitrate. The optical receiver including a shunt-feedback transimpedance amplifier and a limiting amplifier has been designed to have the optimum performance in bitrate ranges from 1 Gbps to 13 Gbps while remaining the transimpedance gain and power efficiency. The prototype chip exhibits −24.2 dBm to −16.8 dBm of optical sensitivity for 10⁻¹² bit error rate and its power efficiency is less than 5 pJ/bit for all operating frequency range.

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A 260 GHz on-off keying (OOK) transmitter (Tx) is presented with distributed switches in V-band fundamental signal path in 65 nm CMOS. Aiming at OOK modulation operating upto 20 Gb/s, distributed switches are integrated in the driving chain to suppress transient ringing from a LC tank in the PA where the modulated input directly switches the Tx output without information distortion. The spatially combined transmitter with on-chip antenna demonstrates upto 14 Gb/s of modulation speed with +5 dBm of equivalent isotropically radiated power (EIRP) at f_r = 246 GHz.

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An innovative concept of noninvasive sensor device has been proposed and successfully demonstrated, which makes direction detections and intensity measurements for electric fields be drastically simplified and agile. Its primal feature is a unique geometry, with the simplicity of Columbus’ egg, where an ammeter and optical readout are internally contained in virtual-shorted parallel plates. While its electromagnetic principle for accurate sensing has been confirmed, its function to promptly image directions and distributions of electric fields has been demonstrated combining its aerial scan with a bulb-shuttered photographic camera.

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Since register files consume a large portion of power in microprocessors. Therefore, this paper proposes that a power saving method in register files can be implemented by eliminating branch instruction redundant read. Experimental results from running various application programs show an average of 8.89% reduction in dynamic switching power, with negligible area overheads.

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In this paper, a new CMOS Gm-C poly-phase filter used in Low-IF receiver is presented. As the requirements of multi-model and multi-band determine the frequency tunability, a master-slave transconductance control circuit is designed. Besides, a low power consumption automatic frequency calibrate circuit is used to resist the PVT. A novel 4^th order poly-phase filter is designed in SMIC 0.18 µm standard CMOS process. Consuming 1.1 mA from a 1.8 V voltage, simlution results show that the filter has a tunability of center frequency from 150 kHz to 500 kHz and bandwith from 100 kHz to 900 kHz independently. Meanwhile, the polyphase filter achieves a IIP3 above 18 dBm.

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Switching mode CMOS frequency multipliers are studied in sub-Terahertz regime. Analysis on the multiplier architectures and optimal gate bias at CMOS switch are investigated to maximize output power at designated harmonics. Utilizing a differential pair, a 195 GHz tripler having a hair-pin filter is designed to maximize 3^rd harmonics with −14.8 dB of conversion gain (CG) from P_in = +13 dBm of the balanced input, while the 260 GHz quadrupler utilizes quadruple-push pairs which achieves CG = −16 dB from two +13 dBm of the balanced I/Q driving signals in a 65 nm digital CMOS process.

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This paper presents a review of the electromechanical theory for microelectromechanical devices emphasizing the mutual transaction between the mechanical and electrical systems. In order to model the devices, an energy function (Lagrangian) is introduced following the derivation of the motion equations. The procedures for drawing equivalent circuits for the devices are then explained, and the characteristics are discussed in terms of a vibration energy harvesting device. Although this paper mainly deals with electrostatic electromechanical devices and a piezoelectric device, modeling of an electromagnetic device is also touched on briefly.

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