In this paper, a compact microstrip open-loop resonator loaded by step impedances cells, is designed to achieve dual-band bandpass filter with tunable resonance frequencies. By adjusting the lengths and widths of the step impedances and the dimensions of the open loop resonator, the simulation results shows the dual-band feature of two passbands at 2.4 and almost 5.2GHz (exactly 5.25). The insertion losses are 0.2dB and 0.4dB at the 2.4GHz and 5.2GHz respectively. There is a good agreement between simulation and measurement results.

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The Volterra series and polynomial based indirect learning digital predistortion methods suffer from the noise at the power amplifiers output. We propose an improvement using two robust non-polynomial functions to substitute the higher items, and utilizing the robust maximum correntropy criterion to replace the minima square error criterion. The convergence of the method is proved and simulations show its robust performance for noisy signals.

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A new low-power Tx FIR driver has been developed targeting for LPDDR4 applications. Both conventional and proposed Tx FIR drivers are designed in 130nm CMOS process and their performances are compared. The proposed 4Gb/s FIR driver gets the vertical and horizontal eye-opening by 64.9% and 89.2%, each respectively, at -14.2dB of channel loss at Nyquist rate and consumes only 370µA from 1.2V supply. An low-dropout (LDO) and Op amp blocks to generate the medium DC voltages of pre-emphasis waveform use 500µA. The entire Tx FIR driver scheme consumes ≤0.9mA and occupies 0.0017mm² only.

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The charge retention mechanism of the λ-DNA molecules with 400bp (136nm) are examined. The DNA solution was dropped on the Si source and drain electrodes with the gap of 120nm. The change of the refresh characteristics by applying the negative voltage to the gate was measured. As a result, it was found that the electron trap remarkably influenced on the hole conduction of the DNA channel. In addition, the DNA has memory ability because the trap and detrap of the electrons can be controlled by the refresh voltage.

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Asymptotic analysis for the transient scattered field when a pulse wave is incident on the edges of a cylindrically curved conducting open sheet is presented. By applying only the Fourier transform method, we derive a novel time-domain (TD) asymptotic solution. The TD asymptotic solution is represented by a superposition of the transient scattered filed elements arrived at the observation point. The validity of the TD asymptotic solution proposed here is confirmed by comparing with both the reference solution and the experimental-numerical results. We show the interesting phenomenon that the creeping wave propagates along the curved conducting sheet later than the whispering-gallery mode.

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A packet memory controller in routers accesses the packet memory according to the QoS requirements of packets. The previous QoS-aware controller using a feedback control loop degenerates into round robin scheduling under temporary overload and suffers from slow response. We propose a new packet memory controller that estimates input load accurately and rapidly and schedules different classes using a flexible bitmap scheduler. The results show that under temporary overload or rapidly changing input loads, it can successfully meet the latency requirements by showing only less than 2% difference from the requirement of the high priority class.

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In this paper, we propose a novel electrically small dual-band reconfigurable antenna. Low- and high-frequency resonances are generated by a substrate-integrated-waveguide (SIW) cavity resonator and a complementary split-ring resonator (CSRR). The overall size is reduced because of the use of an eighth-mode SIW (EMSIW) and an evanescent-mode CSRR. The varactor-loaded CSRR enables only the high frequencies to continuously vary from 2.38GHz to 2.5GHz for channel selection of wireless local area network (WLAN), while the low frequencies are fixed at 1.575GHz for global position system (GPS), because the two resonant frequencies can be independently controlled. The proposed concept is demonstrated by the simulated and measured s-parameters and radiation patterns.

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This paper presents a new memory reduction method of IFFT for OFDM systems, based on a mapping of three IFFT input signals which consist of modulated data, pilot and null signals. The proposed method focuses on reducing the memory size in the bit-reversal part which requires the largest number of memory cells in IFFT architectures. To reduce the memory size, we propose a decimation-in-time (DIT) twiddle factor shifting algorithm to remove the multiplications in the first two stages. It is shown that the proposed method achieves a memory reduction of about 30% compared to previous methods.

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We derive theoretically the power division ratio (PDR) on multi-hop wireless power transfer (WPT) to two receivers coupling with two couplers. The derived expression suggests that the PDR can be controlled by adjusting the load resistance. However, the control range of PDR by adjusting the load resistance of one receiver is limited when a hop count to that receiver is odd number. Therefore we show that the PDR can be controlled by another two methods; control of load resistances of each receiver and control of the load impedance of one receiver. These two methods can control the PDR within coaxial misalignment around the radius of the coupler.

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A novel low-cost dual-polarized radiating element is presented for C-band multifunctional dual-polarized radar system: a compact three-layer configuration with reduced cross-polarized isolation enables frequency reuse using polarization diversity. Promising attributes are demonstrated with measured return loss of better than -10dB from 4.8 to 5.2GHz. The measured gain is larger than 6dBi at 5GHz, along with 29dB cross-polarization discrimination, scanning capability and regular radiation patterns.

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A linearized amplifier using self-mixing feedback technique is presented to cancel out third-order intermodulation distortion (IMD3) terms. Second harmonic terms, which are generated by the self-mixing mixer between base and collector of a BJT amplifier, can be used as a source for IMD3 cancellation. The amplifier is based on a common emitter BJT amplifier with a passive FET mixer and an emitter follower for self-mixing feedback. The amplifier has been implemented with discrete transistors on an FR-4 PCB. Up to 16-dB IMD3 rejection has been achieved by the self-mixing feedback technique at 2GHz with peak output power of 20dBm.

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An ambient-light sensor system using low-temperature poly-silicon thin film transistors was studied, to reduce the power consumption of mobile applications. The proposed system with startup correction can correct the panel-to-panel variation of the ambient-light sensors, without additional equipment. The digital output of the readout circuit has 8 levels per decade for the input luminance ranges from 100 to 10000lux, and the readout rate is 40Hz. The proposed method provides maximum differential non-uniformity below 0.3 LSB.

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Network congestion causes the users cannot perform a real-time streaming service. The paper proposes a real-time and smooth scalable video coding (SVC) streaming system with a bitstream extractor intellectual property (BEIP) design. The system parses the source video to obtain the video information, moreover, adjusts adaptively streaming resolution for limited network bandwidth. The BEIP with very large scale integration (VLSI) implementation, the speed, power consumption, and chip area are 243MHz, 25mW and 1.073×1.028mm², respectively. The IP performs high system throughput of 7.8Gbps to deal with the network traffic.

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