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Distinguished from conventional inductive or resonant method, this paper presents a novel high radiation gain and narrower half-power beamwidth microstrip patch antenna (MPA) array loading with modified-I-shaped(MIS) electromagnetic metamaterials(MTM) to apply in the microwave wireless power transmission(MWPT). The MIS MTM unit cell is simulated in HFSS and the effective parameters of the meta-atom is extracted by homogenization retrieval method. Detailed single MPA numerical computing and modeled simulation is proposed step by step and optimetrics procedure in HFSS is conducted to optimize the design parameters for optimum performance. To better take advantages of the higher directive radiation gain and planer structure, a 6 × 10 × 1 MIS MTM array acting as superstrate is placed above a 2 × 2 MPA array with delicate feeding network and power distribution system. Experiment investigation indicates that the MPA array with superstrate obtained the peak value gain of 17.66 dB compared to original 13.18 dB in the operating frequency of 10 GHz. The half-power beamwidth decreased from 36.775° to 18.645° for the E-plane and reduced to 19.958° from 38.649° for the H-plane respectively. The measured results of the fabricated prototype are consistent with the simulation ones with slight discrepancy. This method offers valuable guidance for designing high efficiency transmitting antenna system in application of MWPT.

Background Lung cancer is one of the most severe cancers and the majority of patients miss the best timing for surgery when diagnosed, thus having to rely on radiotherapy, chemotherapy or target therapy. Epidermal growth factor receptor (EGFR) upregulation occurs in a large percentage of patients, who can then benefit from tyrosine kinase inhibitors (TKI). However, the EGFR mutations they carry will vary the effectiveness of TKI. Circulating tumor DNA (ctDNA) contains genetic information from cancer tissue that can be used as a liquid biopsy by non-invasive sampling. This study aimed to provide a solution for minor allele detection from ctDNA. Methods Our novel method, named multiplex allele-specific blocker PCR (MAB PCR), combines amplification refractory mutation system (ARMS), blocker PCR and fluorescent-labeled probes for better discrimination and higher throughput. MAB PCR was specially designed for low-quality samples such as ctDNA. A sensitive assay based on MAB PCR was developed for enriching and detecting four common EGFR mutations. This assay was optimized and evaluated with manufactured plasmids, and validated with 34 tissue samples and 94 plasma samples. Results The limit of detection of this assay was 102 copies and the detection sensitivity reached 0.1% mutant allele fraction (MAF). The results of clinical sample testing had 100% accordance with sequencing, which proved that this assay was accurate and applicable in clinical settings. Conclusions This assay could accomplish low-cost and rapid detection of 4 common EGFR mutations sensitively and accurately, which has huge potential in clinical usage for guiding medication. Furthermore, this design could be used to detect other mutations.

This paper proposes a novel approach to enhance the aperture efficiency of the transmitting microstrip patch antenna (MPA) by designing a new inclusion of double-cross-shaped metamaterial (DCSM) superstrate applied in microwave wireless power transmission(WPT). Overall WPT model and transmitting antenna selection are briefly introduced and numerical simulation is conducted in HFSS. Homogenization retrieval method based on transmission and reflection coefficients is utilized to calculate the effective parameters of the DCSM unit cell, electric field and surface current distribution are displayed to qualitatively explain the occurrence of negative permittivity and permeability. The Matlab2008a script is also presented to calculate the geometry dimensions of the corresponding conventional patch antenna operating at desired resonant frequency. Simulation results indicate that the gain of the transmitting antenna increases from 7.46 dB to 12.35 dB after loading with the 6 × 3 × 1 array DCSM MTM as the superstrate, the measured gain increases from 7.1 dB to 12.21 dB thus an enhancement of 184% for the transmitting antenna's aperture efficiency is obtained which is of significant value for the whole WPT system. For the last section of our paper, electric field of the transmitting MPA before and after loading with DCSM superstrate are illustrated to gain insight physical mechanism of the gain enhancement.

This paper presents a novel multiple splits octagon-shaped metamaterial which exhibits double left-handed frequency bands roughly from 9.25 GHz to 9.68 GHz and from 15.28 GHz to 15.36 GHz derived from the transmission characteristics by homogenization retrieval method. Two conventional microstrip patch antennas whose resonance frequency bands are located at the first left-handed frequency band and the second one respectively are designed to further investigate the influence by loading the proposed metamaterial as its superstrate. HFSS simulation numerical results indicate that the far field radiation directivity half-power bandwidth(HPBW) of the E-plane and H-plane have reduced by 64%, 63.7% and 59.4%, 59%, and the maximal gain increases from 8.251 dB to 11.024 dB and from 8.5432 dB to 11.9653 dB respectively after loading with the multiple splits octagonal metamaterial superstrate.

To tackle the challenge of surging data rate demand, heterogeneous network (HetNet) composed of multiple radio access technologies (RATs) has been proposed as one promising solution. In addition, the LTE and WLAN Aggregation (LWA) architecture was specified recently, but few existing network selection algorithm takes consideration on the cooperation between RATs. In this paper, we propose new Aggregation based Cell Selection Methods (ACSMs) in order to deal with the cell selection problem for network with LWA architecture. The ACSM calculates the transmission ability of aggregated WLAN into the corresponding eNB's utility function. Simulation results validate that ACSM is effective for user equipment (UE) to select a suitable cellular serving cell to improve the network throughput and quality of user experience as well as the fairness among users.

This paper describes a new highly mobile medium range surveillance radar (YLC-6 radar), which is developed by NRIET. The YLC-6 radar utilizes highly mobile technology, full solid-state transmitter, and an advanced MTD processor to enhance the radar survival capability and tactical performance. This new generation mobile medium range low altitude surveillance radar has military and civil applications.