This paper presents a very efficient scheme for point multiplication on Koblitz curves. The proposed scheme reduces the critical path in the data dependency graph of the point addition operation and increases the utilization of the three parallel multipliers that are used. The proposed scheme exploits an idle multiplier to perform an extra field operation that will be needed in the next iteration. Furthermore, the proposed scheme is implemented on an Altera Stratix II EP2S180F1020C3 FPGA over GF(2¹⁶³) and compared with the related parallel schemes in the literature. The results show that the proposed scheme outperforms the previous schemes in terms of the area-time (AT) and AT² products. Accordingly, the proposed scheme is very attractive for use in high-performance applications.

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A low pass filter (LPF) using High-Low impedance line (Hi-Lo) interdigital Defected Ground Structure (DGS) with compact size and large stopband is presented in this paper. Both of the two characteristics are benefit from the introduction of the high impedance line in the conventional interdigital DGS, which can decrease the transmission zeros of the DGS without changing its overall size. To better explain the principle of the proposed DGS, the equivalent circuit is also built and extracted.

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A compact high-efficiency four-way divider/combiner based on quadruple-ridged waveguide is presented. This divider/combiner designed at 31–38 GHz is mainly composed of the quadruple-ridged transition, which features four-way power divider/combiner as well as transition from waveguide to microstrip. The measured power-combining efficiency of this circuit at 34 GHz is up to 91%, and the combining efficiency is higher than 80% at 31–38 GHz.

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In this paper, a novel topology scheme of photovoltaic inverter is presented. The proposed topology employ the 4-terminal switch-network that consist of three interleaving parallel connection half-bridges and a three winding transformer into low voltage inverter to achieve a multilevel voltage. This new inverter increases the output power and reduce the volume of filter inductance. The operation principle and all switch modes are described in details. Meanwhile, the modulation method is also demonstrated to achieve operation. Finally, simulation and experiment results verify the theoretical analysis.

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This paper presents a new frequency-tunable substrate-integrated waveguide (SIW) filter structure and its fabrication method. The center frequency of the filter is adjusted by moving the membrane structure in each resonator, and the presented fabrication method mainly focuses on how to minimize the number of fabrication steps for constructing the flexible membrane. Due to the simplified process, the filter has advantages of low cost and low risk fabrication. The comparison between a conventional fabrication procedure and the new proposed method is described. For verifying the presented filter structure and fabrication method, two frequency-tunable SIW bandpass filters of the presented structure have been implemented using the presented fabrication method. It is shown that the measured response agrees well with the simulated one. The minimum insertion loss is 0.85 dB, demonstrating that high quality factor can be achieved.

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This paper presents a novel circuit model of electrostatic discharge (ESD) generator for simulation program with integrated circuit emphasis (SPICE) simulation. Calculation and derivation of the waveform generated by the circuit model are demonstrated. The generated waveforms are fully in compliance with the specifications of the IEC 61000-4-2 and Human Metal Model (HMM) standards. Meanwhile, the comparison between simulation waveforms and real waveforms generated by an ESD gun is shown in this work. The ability of the proposed circuit model to predict the measured data is fully explored and clearly summarized.

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In this paper, an all-electronic outdoor wireless communication system based on a Schottky-diode transceiver at 220 GHz is reported. The transceiver is implemented by the use of in-house designed 220 GHz low-noise Schottky diode-based subharmonic mixers (SHMs), which simplifies the system setup and demonstrates the feasibility of Schottky technology for terahertz (THz) communication. The system setup, performance of critical components and link budget calculation are presented. The wireless link quality is evaluated in terms of the error vector magnitude (EVM). 3.52 Gbit/s real-time three-dimension (3D) glass-free video transmission is achieved over an outdoor distance of 200 m by the use of quadrature phase shift keying (QPSK) modulation.

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A signal detector which incorporates differential amplifiers, an RC filter, and a Schmitt trigger is designed for a 6-Gbps 55-nm CMOS SATA receiver. The differential amplifier with the increased gain and common-mode rejection ratio (CMRR) enables the signal detector to have a threshold-voltage range between 110 mV and 165 mV over all the PVT variations, which is 26.7% reduced comparing with the conventional circuit. The signal detector also has a small random threshold variation of ±11.1 mV (±3σ). The proposed signal detector is designed and verified using a 55-nm CMOS technology.

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