Wireless telemetry system for a SAW based microvalve

Abstract

Inductively coupled RF telemetry is an optimal method for both power supply and data transmission in long term artificial implants due to small size, high reliability, and extended life span of the device. In this research, we propose the use of the same technique for secure remote interrogation and powering of a human implantable, Surface Acoustic Wave (SAW) correlation based, passive microvalve. This is carried out by interrogating the microvalve with a Barker sequence encoded BPSK signal. In this paper we present the development of a FEM model for the derivation of the induced voltage on a miniature (2.5×2.5×1 mm), inductively coupled, biocompatible spiral antenna/coil, interrogated by a 7.5×7.5×0.2 cm spiral antenna/coil in the near field. The amount of power transferred at a 30-160 MHz range was derived using the S 21 coupling response when the two antennas are separated by a human body simulant of 5 cm depth. Furthermore, the effect of varying magnetic coupling on the induced voltage, due to the misorientation of coils/antennas is analysed.

Actuation Mechanism of Microvalves: A Review

“…The valve was designed to be driven by the minimum value about electromagnetic (EM) radiation, considering existing EM radiation. Length about the required code was researched to guarantee safe manipulation [122,123,125,126]. Zhang et al reported a novel SAW microvalve consisted of the piezoelectric substrate and an interdigital transducer (27.5 MHz).…”

“…Many microvalves based on SAW are utilized to for the purpose of secure wireless actuation. There are lots of advantages in the realization of a SAW microvalve including secure [122], reliable and low power operation [121], small size [123], simplicity in construction [124] and cost effectiveness [125]. Such microvalves have a huge range of applications such as in micro electro-mechanical systems (MEMS), nano electro-mechanical systems (NEMS) [121], biomedical applications, lab-on-chip applications [124], drug delivery [125,126], and so on.…”