When integrating an optical network into a chip, the communication characteristics and the power cost of the network should be considered. In this letter, to fulfill data coherence communication, a non-intention ring-based optical network which supports multicast and broadcast is studied. To further eliminate the power penalty cost due to waveguide crossing, a layout optimization methodology is proposed. By dividing an optical network into several sections and placing them part-by-part into different areas, the total number of cross points is reduced by 83.3%, 71.7% and 70.2% in networks supporting four-, six- and eight-core communication respectively.
In this paper, a radio frequency (RF) rectifier is proposed for RF energy harvesting. The proposed rectifier adopts a dynamic self-body-biasing technique to modulate the threshold voltage of MOSFET. It can improve the power conversion efficiency (PCE) of the rectifier. Designed with SMIC 0.18 µm CMOS standard process, simulation results indicate that the proposed rectifier has higher PCE than conventional cross coupled rectifier when the input power is larger than −14 dBm. The PCE of proposed rectifier achieves 72.3% when the input power is −3.7 dBm.
Vibration characteristics of two types of piezoelectric transducers with whole-surface electrode and a partially electrode were driven in the thickness direction in air and water acoustic loading on the acoustic radiation surface. Partial electrode transducers had an acoustic loading on the side surface, which is called “siding”. Use of partial electrode transducer allowed the lateral vibration on the acoustic radiation surface to be flattened, and thickness vibration becomes almost uniform. Schlieren observation and wavenumber analysis indicate that lateral waves were identified as Lamb waves. An A1 mode Lamb wave is given as a sample to verify the usefulness of this method.
This paper presents a reconfigurable MIMO handset antenna based on liquid metal. The antenna covers the eight frequency bands of the LTE-A standard. This antenna comprises: a monopole element, a IFA element, and a dual-purpose L-shaped branch which is connected to the ground plane. The function of the L-shaped branch is to improve the isolation, within the low frequency band (698–960 MHz), between two elements. A strip of liquid metal which connects to the arm of the IFA, coordinated with the L-shaped branch, can be used to alter its resonant frequency. The operating principle of this strip is analysed using an equivalent capacitor model. The theory of characteristic mode is used to analyze the properties of proposed antenna. To validate the concept, a prototype antenna with size of 120 × 60 × 0.8 mm3 was fabricated and measured.
A novel static single-phase clocked (SSPC) dual-edge triggered flip-flop (DET-FF) is proposed to allow energy-efficient operation with aggressive voltage scaling. By employing two static latches with a single-phase clock, contention and clock phase mismatch is avoided, which significantly improves tolerance to PVT variations. The post-layout simulation performed with 28 nm CMOS technology shows that the proposed SSPC DET-FF consumes less power and has significantly better power-performance trade off (PDP) than prior-art DET-FFs. Our Monte Carlo analysis also showed that its supply voltage can be aggressively scaled down to 0.3 V even with PVT variations.
In this paper, an ultra-wideband (UWB) antenna with symmetric open slots is proposed. The symmetric open slots and the U-shaped feeding line are introduced for obtaining the symmetrical radiation property and the lower cross-polarization level. By using the U-shaped feeding line to feed the symmetric open slots in parallel, four resonances are excited by the different effective resonant length of the open slots and form a wideband, which locates at 3.1–10.8 GHz. The measured results show that the stable radiation patterns and the low cross-polarization level are obtained in the operating band, which shows that the proposed antenna is a good candidate for UWB applications.
To account for load impedance variation, the extraction methods of conventional nonlinear behavioral model require complex and expensive load-pull system. In this letter, a simplified behavioral model for power amplifier (PA) is demonstrated using nonlinear vector network analyzer (NVNA) only for data extraction. An incident signal at fundamental is added in the output of PA as a disturbance signal, and thus load reflection can be realized when its amplitude and phase are swept as active load-pull system does. To increase the robust of the model, a dynamic sweeping method of output incident signal is proposed which proved can cover most of the areas on the fundamental reflection coefficient chart. This method reduces the variables of the nonlinear behavioral model while dramatically simplifies the measurement architecture and reduces the cost of modeling.
A low-frequency transmissive frequency selective rasorber (FSR) with high in-band transmission and wideband absorption characteristics is proposed and experimentally demonstrated. It comprises the top resistive sheet and the bottom bandpass FSS. For resistive sheet, the tiny strip-type parallel LC resonator composed of square spiral inductor and its two-sided capacitors is inserted between the resistor-loaded crosses to achieve lower insertion loss (IL) by cutting off the lossy path. The bandpass FSS with high selectivity consists of Jerusalem cross slot array and capacitive metallic patches. An IL of 0.3 dB is obtained at 3.55 GHz, and the 10-dB-absorption band is 5.4–13.2 GHz.
In this paper, a dual-mode dual band bandpass filter using stub-loaded stepped-impedance resonators is proposed. Two short stub-loaded resonators are combined together in parallel manner with a common deformation of T-shaped feed line in order to design and analyze two resonators separately. The filter has two passbands centered at 2.45 GHz and 5.33 GHz with the respective fractional bandwidths of 7.7% and 7.1%. Moreover, to the needs of miniaturization, the proposed filter has very compact sizes of 0.15λg × 0.09λg, where the λg is the guided wavelength at the center frequency of the first passband. The group delay responses of the filter meet the requirement of the wireless communication system.