This paper presents a method to wirelessly power sensors using magnetoelectric (ME) structures as receivers. ME receivers consist of composites of magnetostrictive (MS) and piezoelectric material. Using ME receivers, as opposed to inductively coupled coils, is useful when a combination of small size and low frequency are desirable. Most ME receivers require a large DC magnetic field bias for high-performance operation. We present magnetization grading approach with multiple layers of MS material that results in high-performance structures with no DC magnetic field bias required. Our device produces 600 microwatts when excited by a 100 microtesla AC magnetic field at 192.3 kHz. The device is 12.4 mm X 5 mm X 1 mm. The corresponding normalized power density is 10.71 mWcm−3Oe−2, which is the highest reported to our knowledge.
more »
« less
Transformer Based Approach for Wireless Resource Allocation Problems Involving Mixed Discrete and Continuous Variables 2023 IEEE 24th International Workshop on Signal Processing Advances in Wireless Communications (SPAWC)
- Award ID(s):
- 2132700
- PAR ID:
- 10487485
- Publisher / Repository:
- SPAWC
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
Abstract Nearly all biosensing platforms can be described using two fundamental steps—collection and detection. Target analytes must be delivered to a sensing element, which can then relay the transduced signal. For point-of-care technologies, where operation is to be kept simple, typically the collection step is passive diffusion driven—which can be slow or limiting under low concentrations. This work demonstrates an integration of both active collection and detection by using resonant wireless power transfer coupled to a nanogap capacitor. Nanoparticles suspended in deionized water are actively trapped using wireless dielectrophoresis and positioned within the most sensitive fringe field regions for wireless impedance-based detection. Trapping of 40 nm particles and larger is demonstrated using a 3.5 VRMS, 1 MHz radiofrequency signal delivered over a distance greater than 8 cm from the nanogap capacitor. Wireless trapping and release of 1 µm polystyrene beads is simultaneously detected in real-time over a distance of 2.5 cm from the nanogap capacitor. Herein, geometric scaling strategies coupled with optimal circuit design is presented to motivate combined collection and detection biosensing platforms amenable to wireless and/or smartphone operation.more » « less
An official website of the United States government
