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A textile-based wireless pressure sensor array (WiPSA) is proposed for flexible remote tactile sensing applications. The WiPSA device is composed of a fabric spacer sandwiched by two separate layers of passive antennas and ferrite film units. Under the external pressure, the mechanical compression of the flexible fabric spacer leads to an inductance change, which can further be transduced to a detectable shift of the resonant frequency. Importantly, WiPSA integrates the ferrite film featuring an ultrahigh permeability, which effectively improves the device sensitivity and avoids the interference of conductive materials simultaneously. The device performance with a high quality factor (>35) and sensitivity (−0.19 MHz kPa −1 ) within a pressure range of 0-20 kPa is demonstrated. In addition, WiPSA achieves excellent reproducibility under periodical pressures (>20 000 cycles), temperature fluctuations (15-103 °C), and humidity variations (40-99%). As a proof of concept for human-interactive sensing, WiPSA is successfully 1) integrated with a flexible wrist band for fingertip pressure-guided direction choices, 2) developed into a smart wireless insole to map the plantar stress distributions, and 3) embedded into a waist-supporting belt to resolve the contact pressure between the belt and human abdomen in a remote transmitting scheme.

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A new method for pattern reconfigurable antenna (PRA) design is introduced on the basis of a two-element dipole array model in this communication. Firstly, a two-element dipole array loaded with varactor diodes is analyzed in detail. The two dipoles of the array are folded to form a square and the reconfigurable pattern characteristics of the array can be still explained by the phased array theory. And then, based on the two-element dipole array model, a patch top-loaded monopole antenna is proposed to design the PRA (denoted as PTMPRA). Applying the field equivalence principle, the antenna radiation can be analyzed with two couples of magnetic dipoles. The phase of the magnetic dipoles may be adjusted by the loaded varactor diodes, and the antenna can reconfigure the patterns in two orthogonal planes. The antenna is fabricated and measured. The studies validate that the new method for designing pattern reconfigurable patch antenna is simple and efficient.Index Terms-Microstrip antenna, pattern reconfigurable antenna, twoelement dipole array, varactor diode.