Textile Artificial Magnetic Conductor Waveguide Jacket for on-Body Transmission Enhancement

Abstract

Abstract-Diamond dipole antennas with textile Artificial Magnetic Conductor (AMC) sheet-like waveguide were designed to investigate the possibility of improving transmission between antennas. Fleece fabric is used as the substrate of the textile AMC while SHIELDIT fabric is used as the conductive patches and ground plane. The AMC surface is designed to resonate at 2.45 GHz with the goal to enhance the transmission between antennas. A small textile AMC waveguide sheet as well as an AMC waveguide jacket were fabricated. The S-parameters performance of the two antennas with textile AMC sheet was investigated in a free space environment and near to human body setting. The effect of different antennas' orientations was also considered. Measurements were conducted thoroughly to validate the simulated findings. Compared to free space environment, S 21 transmission between two dipoles is improved up to maximum −10 dB when having textile AMC waveguide sheet beneath them. For both off-body and on-body placements, significant transmission enhancement has been observed with the introduction of the AMC sheet-like waveguide. Directive radiation patterns with high gain have also been achieved with the proposed AMC waveguide jacket.

Artificial magnetic conductor for various antenna applications: An overview

“…AMC has also been used to enhance transmissions from one antenna to another, as reported in Ref. . A pair of diamond dipole antennas is separated from one another by a fixed distance with a connection to port 1 and port 2.…”

“… (a) S parameter measurement setup for two set of diamond dipole antenna above AMC array and (b) S 11 and S 21 measurement results for antenna in different condition…”

“…Transmission enhancementImprove the transmission of waves from one antenna to another.

Figure aThe transmission, S 21 between two antennas is improved by 16.3 dB using textile AMC compare to the antenna pairs in the free space. AMC can be useful in Wireless Body Area Network (WBAN) which is subjected to significant loss due to close proximity to the human body by providing a reliable patch between two or more communication devices Improvement antenna impedance matching and in‐phase image current to antennaImprovement of impedance matching widens the antenna bandwidth.…”

Reconfigurable antenna using capacitive loading to Artificial Magnetic Conductor (AMC)

“…The currents then undergo destructive interference with each other which subsequently reduces the antenna gain and radiation efficiency. In contrast, AMC which mimics the behavior of Perfect Magnetic Conductor (PMC) introduces image current which is in phase with the antenna source current at its resonance frequency . The image current then undergoes constructive interference with the source current which subsequently improves the gain and radiation efficiency of the antenna .…”

Numerical and Experimental Analysis of Wideband E-Shape Patch Textile Antenna

“…With the development of body-centric wireless communications [1][2][3][4][5], more and more communications systems contain antennas integrated in clothing, called wearable antennas [6][7][8][9]. Wearable antennas are mainly divided into three types, hard dielectric substrate antenna with low profile and small area [10][11][12], flexible antenna with substrate of foam or flexible PCB (printed circuit board) [13][14][15][16][17], and textile antenna [18][19][20][21][22][23]. Hard dielectric substrate antennas are usually restricted by antenna area and antenna form, and operating bandwidth is often difficult to achieve the requirement.…”