Triple Notch Characteristics Research Articles

Compact triple band notched UWB MIMO antenna with integrated GSM

SummaryThis paper introduces an innovative four‐element Ultra‐wideband (UWB) MIMO structure featuring an integrated global system for mobile (GSM) antenna with the ability to achieve dual and triple band‐notch capabilities. The antenna's distinctiveness is achieved through the utilization of four directional meandered line shaping decoupling structures (MLSDS), an orthogonal arrangement, and multi‐slot techniques. The incorporation of orthogonal separation alongside four directional MLSDS significantly reduces the mutual interference between radiating elements. By placing MLSDS on both sides of the substrate, effective coverage of the GSM band is achieved. The development of the MIMO structure unfolds through four distinct phases. The initial stage lacks MLSDS, while the second stage incorporates MLSDS. The third and fourth stages respectively introduce MLSDS with dual and triple notch characteristics. The presence of MLSDS enhances the antenna's impedance bandwidth (IBW). The intended notches are tailored to address interference from bands like Band n41, WLAN, and X‐band. Furthermore, the proposed antenna has undergone simulation, measurement, and comparative analysis with existing models, focusing on diversity performance metrics. The results reveal its exceptional diversity performance, positioning it as a potential choice for creating a portable UWB‐MIMO system.

Printable Silver Nano Ink for Bendable Ultrawideband Antenna with Triple-Notch Characteristics

Flexible antennas based on the printed flexible electronic technology are of great interest for important applications in wireless communication systems due to their distinctive features over traditional rigid-based antennas. The ultrawideband (UWB), notch characteristics, and bending capabilities of such antennas are crucial for flexible and wearable applications. Currently, only a few are focused on the printed flexible electronics technology with printable ink materials for UWB antenna applications. In addition, flexible UWB antennas with triple-notch characteristics and good bending performance are rarely reported. Thus, there is a need to make advances in this area. Here, we describe the application of a printable silver nanoparticle-based ink for rapidly fabricating an antenna with bendable and triple-notch characteristics designed for UWB communication systems. The ink, composed of monodisperse silver nanoparticles, isopropanol, and ethyl glycol, can easily produce favorable conductive patterns at a sintering temperature below 130 °C after inkjet printing. The antenna is designed on a flexible polyethylene terephthalate (PET) substrate and has a moderate size of 27 mm × 38 mm × 0.12 mm. It operates at a frequency range of 1.9–10.75 GHz, which covers the desired UWB frequency band. By loading a “U”-like slot and two “C”-like slots on the radiating patch, band rejections were generated at 3.2–3.8, 5.3–6.2, and 7.8–8.5 GHz, shielding the interference from world interoperability for microwave access, wireless local area networks, and X uplink bands. The bending results show that the antenna retains good UWB and triple-notch performance even after bending along the Y- or X-axis for different degrees. An antenna prototype was finally fabricated by inkjet printing of the silver nano ink on the PET substrate, exhibiting the desired notch characteristics and excellent bendability. The fabricated antenna prototype proved the feasibility of use as a flexible device at an ultrawide frequency band. The research provides a design guide for flexible antennas with notch features toward flexible and wearable electronics.

Planar EBG Loaded UWB Monopole Antenna with Triple Notch Characteristics

A triple band-notched ultra-wideband (UWB) monopole antenna using a planar electromagnetic bandgap (EBG) design is proposed. The EBG unit cell composed by an Archimedean spiral and inter-digital capacitance demonstrates the notch frequencies. The antenna with EBG cells near the feed line occupies only 30 × 36 mm2 with triple band-rejection characteristics. The three notched bands at 4.2 GHz, 5.2 GHz, and 9.1 GHz can be used in C-band satellite downlink, wireless local area network (WLAN), and X-band radio location for naval radar or military required applications. In addition, the proposed design is flexible to tune different notched bands by altering the EBG dimensions. The parametric analysis is studied in details after placing the EBG unit cells near the feed line to show the coupling effect. The input impedance and surface current distribution analysis are also analyzed to understand the effect of EBG at notch frequencies. The proposed design prototype is fabricated and characterized. A fairly considerable agreement is observed between simulated and measured results.