Method and apparatus with negative resistance in wireless power transfers

摘要

Exemplary embodiments are directed to wireless power transfer. Antenna circuits use negative resistance to offset resistance from other elements in the circuit. The antenna circuits include an antenna for coupling with a near field radiation at a resonant frequency and a capacitance element connected in series with the receive antenna. The antenna circuits also include a negative resistance generator connected in series with the capacitance element. In the case of a receive antenna, and possibly a repeater antenna, a load is connected in series with the negative resistance generator. The load may draw power from the near field radiation when the antenna circuit oscillates near the resonant frequency. In the case of a transmit antenna, a signal generator is coupled in series with the antenna for applying signal power to the antenna circuit to generate an electromagnetic field at the resonant frequency creating a coupling-mode region within a near field.

主权项

1. A wireless power-receive circuit, comprising:
a receive antenna configured to receive power from an electromagnetic field; a capacitance element operably coupled with the receive antenna and comprising a capacitance value and an equivalent series resistance value; and a negative resistance generator operably coupled in series with the capacitance element and coupled to a load, the load configured to draw power from the electromagnetic field, the negative resistance generator being configured to generate a negative resistance value to at least partially offset the equivalent series resistance value and an ohmic resistance of the receive antenna.