Compact Printed Arrays with Embedded Coupling Mitigation for Energy-Efficient Wireless Sensor Networking

Abstract

Wireless sensors emerged as narrowband, resource-constrained devices to provide monitoring services over a wide life span. Future applications of sensor networks are multimedia-driven and include sensor mobility. Thus, sensors must combine small size, large bandwidth, and diversity capabilities. Compact arrays, offering transmit/receive diversity, suffer from strong mutual coupling (MC), which causes lower antenna efficiency, loss of bandwidth, and signal correlation. An efficient technique to reduce coupling in compact arrays is described herein: a defect was inserted in the ground plane (GNDP) area between each pair of elements. The defect disturbed the GNDP currents and offered multidecibel coupling suppression, bandwidth recovery, and reduction of in-band correlation. Minimal pattern distortion was estimated. Computational results were supported by measurements. The bandwidth of unloaded arrays degraded gracefully from 38% to 28% with decreasing interelement distance (0.25 to 0.10). Defect-loaded arrays exhibited active impedance bandwidths 37–45%, respectively. Measured coupling was reduced by 15–20 dB.

Design of a Compact Two Element Mimo Antenna System With Improved Isolation

“…However, this method is complicated and occupies larger areas in the system. In [9], the mutual coupling is minimized by introducing a defect on the ground plane between the antennas. In [10], the mutual coupling has been reduced significantly at the cost of some complicated structure at the ground plane.…”

Robust, electrically small, circular inverted‐F antenna for energy‐efficient wireless microsensors

“…WSN-related antennas need to approach the fundamental performance limits [3][4][5][6][7][8], otherwise the cubic-millimetre 'Smart Dust' node [1,2] will remain a vision. Recently, the WSN antenna discipline has gathered momentum [9][10][11][12][13][14][15][16][17]. Theory predicts that small antenna design should opt for maximum occupation of the hypothetical minimum sphere that circumscribes the 'radiating' parts [3][4][5][6][7][8].…”

Compact split‐ring resonator‐loaded multiple‐input–multiple‐output antenna with electrically small elements and reduced mutual coupling

“…In practice, the value of the envelope correlation coefficient should be as low as possible. Several techniques have been proposed to reduce mutual coupling, including the use of parasitic elements [8], electromagnetic bandgap structures [9,10], slots [11][12][13], resonators [14], metasurfaces [15], fields cancelation [16], polarisation diversity [17][18][19], radiation pattern diversity [20] and other techniques [5,[21][22][23][24]. In particular, metamaterials have been proposed as an alternative means to decouple adjacent antennas [4,23,25].…”