Large area power transmitter for wireless power transfer

A transmitter for wireless power transfer, comprising:

• a variable form factor transmitter having a form factor changeable by a user, adapted to form a plurality of cross-coupled segments, each forming a respective transmitter loop, disposed about a pre-determined wireless power transfer area, the respective transmitter loops formed from a string of distributed capacitors having a plurality of capacitors connected in series with one another via a plurality of wire segments, wherein each of the plurality of capacitors comprises a pre-determined capacitance, and each of the plurality of wire segments comprises a pre-determined segment length and a pre-determined inductance per unit length, adjacent ones of the plurality of cross-coupled segments inducing respective magnetic fields having opposite direction to each other when driven together by a radio frequency (RF) power source;
• wherein the plurality of cross-coupled segments are configured to:
• transmit, from the RF power source and based at least in part on a characteristic frequency dependent on at least the pre-determined capacitance and the pre-determined inductance per unit length, RF power across the pre-determined wireless power transfer area via a near electromagnetic field of the transmitter;
• and
• reduce, based on opposing directions of magnetic fields induced by adjacent cross-coupled segments of the plurality of cross-coupled segments, a radiation loss of the wireless power transfer due to a far electromagnetic field of the transmitter.

A system for wireless power transfer, comprising:

• a variable form factor transmitter having a form factor changeable by a user, adapted to form a plurality of cross-coupled segments, each forming a respective transmitter loop, disposed about a pre-determined wireless power transfer area, the respective transmitter loops formed from a string of distributed capacitors having a plurality of capacitors connected in series with one another via a plurality of wire segments, wherein each of the plurality of capacitors comprises a pre-determined capacitance, and each of the plurality of wire segments comprises a pre-determined segment length and a pre-determined inductance per unit length;
• and
• a radio frequency (RF) power source coupled to the plurality of cross-coupled segments, adjacent ones of the plurality of cross-coupled segments inducing respective magnetic fields having opposite direction to each other when driven together by the RF power source, wherein the plurality of cross-coupled segments are configured to:
• transmit, from the RF power source and based at least in part on a characteristic frequency dependent on at least the pre-determined capacitance and the pre-determined inductance per unit length, RF power across the pre-determined wireless power transfer area via a near electromagnetic field of the plurality of cross-coupled segments;
• and
• reduce, based on opposing directions of magnetic fields induced by adjacent cross-coupled segments of the plurality of cross-coupled segments, a radiation loss of the wireless power transfer due to a far electromagnetic field of the plurality of cross-coupled segments.