Abstract:
The present disclosure provides a method and apparatus for improved wireless charging pads for charging and/or powering electronic devices. Such pads may not require a power chord for connecting to a main power supply, for example a wall outlet. In contrast, power may be delivered wireless to the foregoing pads through pocket-forming. A transmitter connected to a power source may deliver pockets of energy to the pads which through at least one embedded receiver may convert such pockets of energy to power. Lastly, the pads may power and/or charge electronic devices through suitable wireless power transmission techniques such as magnetic induction, electrodynamics induction or pocket-forming.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 13/939,706, filed Jul. 11, 2013, which is herein fully incorporated by reference in its entirety. 
     The present disclosure is related to U.S. patent application Ser. No. 13/891,430, filed May 10, 2013; U.S. patent application Ser. No. 13/925,469, filed Jun. 24, 2013; U.S. Non-Provisional patent application Ser. No. 14/583,625, filed Dec. 27, 2014, entitled “Receivers for Wireless Power Transmission,” U.S. Non-Provisional patent application Ser. No. 14/583,630, filed Dec. 27, 2014, entitled “Methodology for Pocket-Forming,” U.S. Non-Provisional patent application Ser. No. 14/583,634, filed Dec. 27, 2014, entitled “Transmitters for Wireless Power Transmission,” U.S. Non-Provisional patent application Ser. No. 14/583,640, filed Dec. 27, 2014, entitled “Methodology for Multiple Pocket-Forming,” U.S. Non-Provisional patent application Ser. No. 14/583,641, filed Dec. 27, 2014, entitled “Wireless Power Transmission with Selective Range,” U.S. Non-Provisional patent application Ser. No. 14/583,643, filed Dec. 27, 2014, entitled “Method for 3 Dimensional Pocket-Forming,” all of which are fully incorporated herein by reference in their entirety for all purposes. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to charging pads, and more particularly to portable wireless charging pads. 
     BACKGROUND 
     Electronic devices, such as laptop computers, smartphones, portable gaming devices, tablets and so forth may require power for performing their intended functions. This may require having to charge the electronic device at least once a day, or in high-demand electronic devices more than once a day. Such an activity may be tedious and may represent a burden to users. For example, a user may be required to carry chargers in case one of his or her electronic devices is lacking power. In addition, users have to find available power sources to connect to. Lastly, users must plugin to a wall or other power supply to be able to charge his or her electronic device. However, such an activity may render electronic devices inoperable during charging. Current solutions to this problem may include inductive charging pads which may employ magnetic induction or resonating coils. Nevertheless, such a solution may still require that electronic devices may have to be placed in a specific place for powering. Thus, the electronic devices during charging may not be portable. For the foregoing reasons, there is a need for charging pads with improved mobility and portability. 
     SUMMARY 
     The present disclosure provides a method and apparatus for improved wireless charging pads for powering and/or charging electronic devices such as smartphones, tablets and the like. 
     A portable wireless charging pad, comprises a pad receiver embedded within the charging pad and connected to antenna elements on a surface of the pad for receiving pockets of energy from a pocket-forming power transmitter to charge a pad battery; and a pad pocket-forming transmitter powered by the pad battery including a RF chip connected to antenna elements for generating pockets of energy to charge or power a portable electronic device having a receiver to capture the pockets of energy from the pad transmitter in proximity to the charging pad. 
     In an embodiment, a description of pocket-forming methodology using at least one transmitter and at least one receiver may be provided. 
     In another embodiment, a transmitter suitable for pocket-forming including at least two antenna elements may be provided. 
     In a further embodiment, a receiver suitable for pocket forming including at least one antenna element may be provided. 
     In an embodiment, a cordless pad for powering electronic devices including at least one embedded receiver with antennas placed alongside the edge of the pad may be provided. 
     In an even further embodiment, a cordless pad for powering electronic devices including at least one embedded receiver with antennas placed on the top surface of the pad may be provided. As an alternative, cordless pads may employ various methods for powering electronic devices such as magnetic induction, electrodynamics induction or pocket-forming. 
     In yet another embodiment, a cordless pad with a charging module may be provided. 
     In an embodiment, a pad embedded within suitable apparel such as backpacks, briefcases and the like may be provided. 
     The disclosed embodiments provide wireless charging pads that may not require a power cord for connecting to a power supply. Thus, mobility and portability may greatly be enhanced in such pads. In addition, pads utilizing pocket-forming for connecting wirelessly to a power supply and for delivering power to electronic devices may increase the mobility of electronic devices while charging. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the present disclosure are described by way of example with reference to the accompanying figures, which are schematic and may to be drawn to scale. Unless indicated as representing, prior art, the figures represent aspects of the present disclosure. 
         FIG. 1  illustrates wireless power transmission using pocket-forming, according to the present disclosure. 
         FIG. 2  illustrates a component level illustration for a transmitter which may be utilized to provide wireless power transmission as described in  FIG. 1 , according to the present disclosure. 
         FIG. 3  illustrates a component level embodiment for a receiver which can be used for powering or charging an electronic device as described in  FIG. 1 , according to the present disclosure. 
         FIG. 4  illustrates a wireless power transmission where a pad, with improved portability, may provide wireless power to an electronic, according to the present disclosure. 
         FIG. 5  illustrates a wireless power transmission where an alternate pad, with improved portability, may provide wireless power to an electronic device, according to the present disclosure. 
         FIG. 6  illustrates a portable pad which may include a module for storing charge, according to the present disclosure. 
         FIG. 7  illustrates an example situation where pad from  FIG. 6  can be used, according to the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     “Pocket-forming” refers to generating two or more radio frequency (“RF”) waves which converge in three-dimensional (“3-D”) space, forming controlled constructive and destructive interference patterns. 
     “Pockets of energy” refers to areas or regions of space where energy or power accumulates in the form of constructive interference patterns of RF waves. 
     “Null-space” refers to areas or regions of space where pockets of energy do not form because of destructive interference patterns of RF waves. 
     “Transmitter” refers to a device, including a chip which generates two or more RF signals, at least one RF signal being phase shifted and gain adjusted with respect to other RF signals, substantially all of which pass through any number of RF antennas, such that focused RF signals are directed to a target. 
     “Receiver” refers to a device that includes at least one antenna element, at least one rectifying circuit and at least one power converter, which utilizes pockets of energy for powering, or charging an electronic device. 
     “Adaptive pocket-forming” refers to dynamically adjusting pocket-forming to regulate power on one or more targeted receivers. 
     In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, which may not be to scale or to proportion, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings and claims, are not meant to be limiting. Other embodiments may be used and/or and other changes may be made without departing from the spirit or scope of the present disclosure. 
     A. Essentials of Pocket-Forming 
       FIG. 1  illustrates wireless power transmission  100  using pocket-forming. A transmitter  102  may transmit controlled Radio Frequency (RF) waves  104  which may converge in 3-d space. These RF waves may be controlled through phase and/or relative amplitude adjustments to form constructive and destructive interference patterns (pocket-forming). Pockets of energy  106  may form at constructive interference patterns and can be 3-dimensional in shape whereas null-spaces may be generated at destructive interference patterns. A receiver  108  may then utilize pockets of energy  106  produced by pocket-forming for charging or powering an electronic device, for example a laptop computer  110  and thus effectively providing wireless power transmission. In some embodiments, there can be multiple transmitters  102  and/or multiple receivers  108  for powering various electronic devices, for example smartphones, tablets, music players, toys and others at the same time. In other embodiments, adaptive pocket-forming may be used to regulate power on electronic devices. 
       FIG. 2  illustrates a component level embodiment for a transmitter  200  which may be utilized to provide wireless power transmission  100  as described in  FIG. 1 . Transmitter  200  may include a housing  202  where at least two or more antenna elements  204 , at least one RF integrated circuit (RFIC)  206 , at least one digital signal processor (DSP) or micro-controller  208 , and one optional communications component  210  may be included. Housing  202  can be made of any suitable material which may allow for signal or wave transmission and/or reception, for example plastic or hard rubber. Antenna elements  204  may include suitable antenna types for operating in frequency bands such as 900 MHz, 2.5 GHz or 5.8 GHz as these frequency bands conform to Federal Communications Commission (FCC) regulations part  18  (Industrial, Scientific and Medical equipment). Antenna elements  204  may include vertical or horizontal polarization, right hand or left hand polarization, elliptical polarization, or other suitable polarizations as well as suitable polarization combinations. Suitable antenna types may include, for example, patch antennas with heights from about 1/24 inches to about 1 inch and widths from about 1/24 inches to about 1 inch. Other antenna elements  204  types can be used, for example meta-materials, dipole antennas among others. RFIC  206  may include a proprietary chip for adjusting phases and/or relative magnitudes of RF signals which may serve as inputs for antenna elements  204  for controlling pocket-forming. These RF signals may be produced using an external power supply  212  and a local oscillator chip (not shown) using a suitable piezoelectric material. Micro-controller  208  may then process information send by a receiver through its own antenna elements for determining optimum times and locations for pocket-forming. In some embodiments, the foregoing may be achieved through communications component  210 . Communications component  210  may be based on standard wireless communication protocols which may include Bluetooth, Wi-Fi or ZigBee. In addition, communications component  210  may be used to transfer other information such as an identifier for the device or user, battery level, location or other such information. Other communications component  210  may be possible which may include radar, infrared cameras or sound devices for sonic triangulation for determining the device&#39;s position. 
       FIG. 3  illustrates a component level embodiment for a receiver  300  which can be used for powering or charging an electronic device as exemplified in wireless power transmission  100 . Receiver  300  may include a housing  302  where at least one antenna element  304 , one rectifier  306 , one power converter  308  and an optional communications component  310  may be included. Housing  302  can be made of any suitable material which may allow for signal or wave transmission and/or reception, for example plastic or hard rubber. Housing  302  may be an external hardware that may be added to different electronic equipment, for example in the form of cases, or can be embedded within electronic equipment as well. Antenna element  304  may include suitable antenna types for operating in frequency bands similar to the bands described for transmitter  200  from  FIG. 2 . Antenna element  304  may include vertical or horizontal polarization, right hand or left hand polarization, elliptical polarization, or other suitable polarizations as well as suitable polarization combinations. Using multiple polarizations can be beneficial in devices where there may not be a preferred orientation during usage or whose orientation may vary continuously through time, for example a smartphone or portable gaming system. On the contrary, for devices with well-defined orientations, for example a two-handed video game controller, there might be a preferred polarization for antennas which may dictate a ratio for the number of antennas of a given polarization. Suitable antenna types may include patch antennas with heights from about 1/24 inches to about 1 inch and widths from about 1/24 inches to about 1 inch. Patch antennas may have the advantage that polarization may depend on connectivity, i.e. depending on which side the patch is fed, the polarization may change. This may further prove advantageous as a receiver, such as receiver  300 , may dynamically modify its antenna polarization to optimize wireless power transmission. Rectifier  306  may include diodes or resistors, inductors or capacitors to rectify the alternating current (AC) voltage generated by antenna element  304  to direct current (DC) voltage. Rectifier  306  may be placed as close as is technically possible to antenna element  304  to minimize losses. After rectifying AC voltage, DC voltage may be regulated using power converter  308 . Power converter  308  can be a DC-DC converter which may help provide a constant voltage output, regardless of input, to an electronic device, or as in this embodiment to a battery  312 . Typical voltage outputs can be from about 5 volts to about 10 volts. Lastly, communications component  310 , similar to that of transmitter  200  from  FIG. 2 , may be included in receiver  300  to communicate with a transmitter or to other electronic equipment. 
     B. Improved Wireless Charging Pad 
       FIG. 4  illustrates a wireless power transmission  400  where a pad  402 , with improved portability, may provide wireless power to a smartphone  404 . In the prior art, pad  402  may include a power chord which may connect to a wall outlet running on alternating current (AC) power. Such AC power may then be transmitted wirelessly to smartphone  404 , through magnetic induction or electrodynamics induction, via a plurality of inductive elements  406 . Inductive elements  406  may include, for example, coils or inductors. As is known in the prior art, smartphone  404  may also incorporate external hardware, such as cases, which may include a plurality of inductive elements  406  (not shown) for receiving the power sent by pad  402 . The foregoing configuration may not really be wireless because a power chord may still be required. In addition, the location of pad  402 , and therefore of smartphone  404  may negatively be affected by the location of an available power outlet, i.e. if the wall outlet is in hard-to-reach locations such as behind a sofa or TV screen, so will be pad  402  and smartphone  404 . The foregoing situation can easily be solved by eliminating the power chord used in the prior art. In an embodiment, wireless power transmission  400  may be carried out using a transmitter  408  and embedding at least one receiver (not shown) within pad  402 . Transmitter  408  may provide pockets of energy  410  to embedded receivers which may provide power to inductive elements  406  from pad  402  for powering smartphone  404  wirelessly. Antenna elements  412  (as described with reference to at least one of  FIG. 2  and  FIG. 3 ), from the foregoing embedded receivers, may be placed outside the edges of pad  402  for improved power reception independent of the location of transmitter  408 . The foregoing configuration may be beneficial because pad  402  may no longer be constrained by the location of a suitable wall outlet. In addition, pad  402  can be put in easy-to-reach locations such as tables, counters and the like that are inside the range of transmitter  408 . In some embodiments the range of transmitter  408  can be up to about 15 feet. The foregoing can be achieved by placing about 256 antennas in transmitter  408 , and an embedded receiver with about 80 antennas. The power transmitted can be up to one watt. 
       FIG. 5  illustrates another embodiment of wireless power transmission  400  where a pad  502  (similar to pad  402  from  FIG. 4  above) may include a plurality of inductive elements  406  and at least one embedded receiver (not shown). Embedded receivers may include antenna elements  412  located on the top surface of pad  502 . This configuration may be beneficial when using a transmitter  504  located above pad  502 , for example in ceilings. In other embodiments, the foregoing pads, as described through  FIG. 4  and  FIG. 5 , may not use inductive elements  406 , but in contrast may utilize pocket-forming for transmitting power wirelessly. For example, transmitter  408  may provide power to either pad  402  or pad  502  through pocket-forming. Then, a second transmitter within either pad  402  or pad  502  may re-transmit the power sent by transmitter  408  to electronic devices nearby the aforementioned pads. Lastly, electronic devices requiring power may incorporate external hardware, for example cases, similar to those utilized in the prior art for magnetic induction or electrodynamics induction. Such external hardware may incorporate receivers suited for pocket-forming instead of inductive elements  406 . The aforementioned configuration may further expand the range wireless power transmission  400  because electronic devices such as smartphone  404  may not even be required to be placed on the pads, but only near the pads (up to 15 feet away for example). Thus, pad  402  or pad  502  may need only to be from about 2 inches×4 inches in surface area. 
       FIG. 6  illustrates a pad  600  which in this embodiment may include a plurality of inductive elements  406 , at least one embedded receiver (not shown) for powering smartphone  404 . As described above, with reference to at least one of  FIG. 4  and  FIG. 5 , pad  600  may receive power wireless through pocket-forming and may not require a power chord for connecting to a power supply such as a wall outlet. In some embodiments, pad  600  may also include at least one module  602  for storing charge, for example a lithium ion battery. Module  602  may store charge while charging or not smartphone  404 . In some embodiments, pad  600  may utilize magnetic induction, electrodynamics induction of pocket-forming for powering smartphone  404  as described through  FIG. 4  and  FIG. 5 . Once pad  600  is charged, it may be placed at any location, or even carried around for powering electronic devices as described in  FIG. 7  below. 
       FIG. 7  illustrates an example situation  700  where pad  600  may be carried around in a briefcase  702  for powering smartphone  404 . Pad  600  can be carried in backpacks, women purses and the like. In some embodiments, pad  600  may be embedded within the foregoing items and sold as one charging unit. Furthermore, such a charging unit can be powered wirelessly through pocket-forming or may incorporate a power chord for plugging into a wall outlet. Devices inside a bag, purse or the like are by default not in use, and can therefore sacrifice mobility while powering using the former option. 
     While various aspects and embodiments have been disclosed herein, other aspects and embodiments are contemplated. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.