Graduate Thesis Or Dissertation

 

Characterization and Design of a Low-Power Wireless Power Delivery System Public Deposited

https://scholar.colorado.edu/concern/graduate_thesis_or_dissertations/st74cq62z
Abstract
  • This thesis focuses on a design methodology for low-power non-directional far-field wireless powering. The power receiver consists of one or more antennae which receive plane waves transmitted by the powering source, and deliver the RF power to a rectifying element. The resulting DC power is optimally transferred to the electronic application via a power management circuit. The powering is independent of the electronic application which can include wireless transmission of sensor data.

    The design and implementation of an integrated rectifier-antenna at low incident power densities (from 25-200μW/cm2) is presented. Nonlinear source-pull measurements and harmonic balance simulations are used for finding the optimal rectifying device RF and DC impedances for efficient rectification. Experimental results show that an antenna design with a specific complex impedance reaches the highest rectification efficiency. Several examples of the design methodology are shown. In specific, characterization of a linearly polarized rectifying patch antenna at frequency of 1.96 GHz is detailed, with an optimal RF impedance of 137+j149Ω and an optimal DC load of 365Ω resulting in RF to DC conversion efficiency of 63% (simulated) for the rectifier alone and 54% (measured) for the total rectifying antenna. A compact design (eliminating SMA connector) of a dual-polarized rectifier antenna integrated with two rectifiers, one for each polarization is detailed. The complications and issues of combining the powers from the two polarizations are addressed. A analysis of required RF and DC isolation in multiple-rectifier integrated rectifier-antenna is developed and confirmed. Measurement results of a 2.45 GHz integrated rectifier antenna show conversion efficiency of 56% and very small dependance on rotation angle between powering polarization and receiving rectifier antenna (ratio of maximum to minimum power as the antenna is rotated of 1.09).

Creator
Date Issued
  • 2011
Academic Affiliation
Advisor
Committee Member
Degree Grantor
Commencement Year
Subject
Last Modified
  • 2020-02-11
Resource Type
Rights Statement
Language

Relationships

Items