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Wearable e-textile near-field communication (NFC) radio-frequency identification (RFID) antennas fully integrated with garments using embroidery techniques, which enables everyday clothing to become connective to wireless communication systems, is presented. The e-textile wearable antennas have been designed through full electromagnetic wave simulation based on the electrical properties of conductive threads and textile substrates at the high frequency band, allocated for NFC wireless communications. The e-textile wearable NFC antenna performance under mechanical bending as well as human body effects have been experimentally studied and evaluated; the antennas can operate under significantly bending angle and body effects attributed to its broad operating bandwidth. This is highly desirable and distinguished to conventional NFC antennas; the proposed e-textile wearable NFC antennas can be placed almost any place on clothes and still capable to communicate at the desired operating frequency of 13.56 MHz. The maximum read range of the e-textile wearable NFC tags is measured to be around 5.6 cm, being compatible to typical commercially available metallic NFC tags. The e-textile wearable NFC tags can lead to numerous potential applications such as information exchange, personal security, health monitoring and Internet of Things. [ABSTRACT FROM AUTHOR]

This study introduces a compact asymmetric coplanar strip (ACS)-fed composite right--left-handed (CRLH) multipleinput--multiple-output (MIMO) antenna for multiband operation. The ACS fed MIMO antenna is composed of two elements; each is operating at 5, 5.8 and 6.3 GHz; for different wireless applications. The overall MIMO antenna size is compact (46 x 26 mm²). A unit cell of the CRLH connected to 50 Ω ACS fed is considered the main block of the antenna. The edge-to-edge separation between antenna elements equals 0.4λ0 at 5 GHz. The insertion loss, correlation coefficient, diversity gain and channel capacity are used to evaluate the performance of the ACS-fed MIMO antenna. The isolation higher than 25 dB and envelope correlation lower than 0.05 have been achieved without using any extra decoupling structures. The experimental results are reasonably well agreed with simulated ones. [ABSTRACT FROM AUTHOR]

Microstrip antennas suffer an inherent disadvantage of narrow impedance bandwidth, normally within 5%. In this article, a single layer linear U-slot microstrip patch antenna array is designed, fabricated and characterised. The measured results agree well with the simulated, showing an enhanced impedance bandwidth (voltage standing wave ratio < 2) of 10.6%, ranging from 5.35 to 5.95 GHz, on an FR4 substrate. The antenna array has high efficiency and gain. Only a pair of sidelobes appear in the E plane radiation pattern. The reported linear array design can provide a method of expanding to 4 × N antenna array for satellite to ground communication operating at C band. [ABSTRACT FROM AUTHOR]