An All-Textile Dual-Band Antenna for BLE and LoRa Wireless Communications

Abstract

In this paper, a dual-band conductive textile-based wearable antenna operating at LoRa-868 MHz and BLE-2.4 GHz is presented. The proposed antenna is intended for accurate geolocation, tracking and communication applications in the military, industrial and telemedicine industries. The low-profile patch antenna is suitable for integrating into clothing. It is composed of three textile layers: top and bottom silver-ink-printed polystyrene fabrics, and a neoprene substrate. To utilize the flexible and restorable properties of these textile materials, the proposed antenna is directly fed by a flexible cable using an aperture-coupled feeding technique. This method not only eliminates the use of the conventional, bulky, and metallic SMA connector but also introduces a secondary resonance at 2.4 GHz, enabling the dual-band property. Using a thin coaxial cable fixed on the aperture slot for proximity coupling, a compact antenna size of 150 mm2 is obtained that can easily be attached and detached on existing cloths. The proposed structure has been fabricated and measured in an anechoic chamber to verify the performance. Measured gain of 3.28 dBi and 3.25 dBi was realized for LoRa and BLE at an antenna size of 0.61 λg × 0.61 λg × 0.012 λg (where λg is guided wavelength at 868 MHz) with a front-to-back ratio (FBR) of greater than 10 dBi.

Parasitic Loaded Shorting Pin Based Compact Multi-slot LoRa Antenna for Military Application

“…Microstrip patch antennas with the features like compatibility, low profile and easy to integrate are hence preferred for such IoT applications. In recent years, a lot of antennas working in different IoT environment as well as LoRa technology have been reported [6][7][8][9][10][11][12][13][14]. An inverted F-antenna for IoT devices using LoRa technology is designed for a single resonating frequency band in [6].…”

“…A CubeSat microstrip antenna with metamaterial structure is proposed for LoRa communication in [7]. In [9], a dual-band conductive textile-based wearable antenna operating at LoRa and Bluetooth range is proposed for application in accurate geolocation, tracking and communication in the military and telemedicine industries. In [10] various techniques for miniaturization of antenna are reported with a proposed inset fed rectangular microstrip antenna resonating at LoRa band.…”

Machine Learning-Optimized Compact Frequency Reconfigurable Antenna With RSSI Enhancement for Long-Range Applications

“…In [27], a low-profile dual-band wearable patch antenna designed for BLE-2.4 GHz and LoRa 868 MHz applications was introduced. The antenna utilizes silver-ink-printed polystyrene fabrics for the radiator and ground plane, with a neoprene substrate.…”

Compact Tri-band Loaded Antenna for wireless Communication and Fifth generation Applications

“…A 30 × 42 mm2 substrate with L-shaped strips is utilised in [21] to achieve tri-band functioning. A comparatively bigger CPW fed slotted antenna has also been proposed in [22] UWB antennas operate above the two wide frequencies of the upper band, which extends from 5.85 to 10.6 GHz, and the lower band, which runs from 3.1 to 5.1 GHz. The next wave of wireless systems, which includes 6 GHz (WiFi-6E) and 5G (B5G)/6G wireless sensor technologies, is now being developed by top wireless technology firms.3,4.…”