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Abstract-Two kinds of band-notched ultra wide-band slot antennas are proposed. Printed on a dielectric substrate of FR4 with relative permittivity of 4.4 and fed by a 50 Ω microstrip line, the proposed antennas introduce semicircular annular strips to reject the frequency band (5.15-5.85 GHz) limited by IEEE802.11a. The parameters which affect the performance of the antennas in terms of its frequency domain characteristics are investigated in this paper.

In this paper, a novel compact four-element ultra-wideband (UWB) multiple-input multipleoutput (MIMO) antenna with triple band-notched characteristics is proposed. The proposed antenna is composed of four slot antenna elements with a common rhombic slot, each feeding by a microstrip-fed line to greatly reduce the overall size of the antenna. It has a compact size of 34 mm × 34 mm × 1.6 mm. The high isolation and polarization diversity are achieved by placing the four microstrip-fed lines perpendiculars to each other, while a parasitic strip is employed as a decoupling structure between adjacent microstrip-fed lines to further improve isolation. Moreover, the proposed antenna can achieve triple band-notched characteristics by embedding L-shaped and C-shaped slots on each radiator and loading electromagnetic band gap (EBG) structures next to micro-strip feeders respectively. As a result, the proposed antenna obtains three notched bands of 3.3-3.9 GHz, 5-6 GHz, and 7.4-8.5 GHz, which are in good agreement with the interference bands of WiMAX (3.3-3.7 GHz), WLAN (5.15-5.875 GHz) and X-band (7.3-8.5 GHz), respectively. The antenna prototype has been fabricated and measured. The results show that the antenna has an impedance bandwidth of 2.5-12 GHz (except for the three notched bands). Besides, the isolation among the elements, envelope correlation coefficient, radiation characteristics, efficiency, realized gain, and total active reflection coefficient are also investigated. The experimental results indicate that the proposed antenna can be a good candidate for UWB-MIMO wireless communication applications.INDEX TERMS UWB-MIMO antenna, triple band-notched characteristics, electromagnetic band gap (EBG), compact size.

Because China is becoming an aging society, the incidence of diabetes and diabetic foot have been increasing. Diabetic foot has become one of the main health-related killers due to its high disability and mortality rates. Negative pressure wound therapy (NPWT) is one of the most effective techniques for the treatment of diabetic foot wounds and great progress, both in terms of research and its clinical application, has been made in the last 20 years of its development. However, due to the complex pathogenesis and management of diabetic foot, irregular application of NPWT often leads to complications, such as infection, bleeding and necrosis, that seriously affect its treatment outcomes. In 2020, under the leadership of Burns, Trauma and Tissue Repair Committee of the Cross-Straits Medicine Exchange Association, the writing group for ‘Consensus on the application of negative pressure wound therapy of diabetic foot wounds’ was established with the participation of scholars from the specialized areas of burns, endocrinology, vascular surgery, orthopedics and wound repair. Drawing on evidence-based practice suggested by the latest clinical research, this consensus proposes the best clinical practice guidelines for the application and prognostic evaluation of NPWT for diabetic foot. The consensus aims to support the formation of standardized treatment schemes that clinicians can refer to when treating cases of diabetic foot.

A compact dual-band dual-polarized log-periodic dipole array with a dimension of 160×160×60 mm 3 for MIMO WLAN applications is proposed. In this antenna, there are 12 antennas,six for horizontal polarization and six for vertical polarization.In order to achieve dual linear polarizations and beam switching ,six horizontal antennas are placed in sequential, rotating arrangement on a horizontal substrate panel with an equal inclination angle of 60 o to form a symmetrical structure, while the other six antennas for vertical polarization are inserted through slots made on the horizontal substrate panel. Futhermore, six pairs of double T-type slits are introduced to mainly reduce the mutual coupling between the horizontal antennas.The proposed array is manufactured and exhibits the characteristics of high isolation, good front-to-back ratio,and average gains of 5 and 6 dBi over the 2.4 and 5 GHz ban d,respectively.The MIMO performance of the array is analyzed and evaluated by mutual coupling and the envelope correlation coefficient.