Wireless charging with multiple power receiving facilities on a wireless device

The disclosed system utilizes multiple wireless power receivers (antennas and or paths) for receiving power. The disclosed system includes a chip, such as an application specific chip (ASICs) connectable to multiple antennas and units to convert radio frequency (RF) power into direct current (DC) power. The disclosed system can also include antennas that are used to receiving power, communicate, and send a beacon signal. The disclosed system also comprises a mobile electronic device to receive wireless power using multiple antennas connected or coupled to multiple wireless power receivers.

TECHNICAL FIELD

The technology described herein relates generally to the field of wireless communication and power transmission. More specifically, the technology relates to wireless power transfer to a device with multiple wireless power receivers.

BACKGROUND

Many portable electronic devices are powered by batteries. Rechargeable batteries are often used to avoid the cost of replacing conventional dry-cell batteries and to conserve precious resources. However, recharging batteries with conventional rechargeable battery chargers requires access to an alternating current (AC) power outlet, which is sometimes not available or not convenient. It would, therefore, be desirable to derive power for a battery charger from EM radiation.

Accordingly, a need exists for technology that overcomes the problem demonstrated above, as well as one that provides additional benefits. The examples provided herein are of some prior or related systems and their associated limitations are intended to be illustrative and not exclusive. Other limitations of existing or prior systems will become apparent to those of skill in the art upon reading the following Detailed Description.

Overall, the examples herein of some prior or related systems and their associated limitations are intended to be illustrative and not exclusive. Other limitations of existing or prior systems will become apparent to those of skill in the art upon reading the following.

DETAILED DESCRIPTION

Consequently, alternative language and synonyms may be used for any one or more of the terms discussed herein, and no special significance is meant when a term is elaborated upon herein. Synonyms for certain terms are provided. A recital of one or more synonyms does not exclude the use of other synonyms. The use of examples anywhere in this specification, including examples of any terms discussed herein, is illustrative only, and is not intended to further limit the scope and meaning of the disclosure or of any term. Likewise, the disclosure is not limited to various embodiments given in this specification.

Without intent to further limit the scope of the disclosure, examples of instruments, apparatus, methods and their related results according to the embodiments of the present disclosure are given below. Note that titles or subtitles may be used in the examples for convenience of the reader, and in no way limit the scope of the disclosure. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. In the case of conflict, the present document, including definitions, will control.

Embodiments of the present disclosure describe various techniques for wirelessly charging and/or wireless power delivery from one or more chargers to one or more wireless devices (also referred to herein as “devices” or “target devices”) having embedded, attached, and/or integrated power receiver clients (also referred to herein as “wireless power receivers” or “clients”).

The techniques described herein utilize wireless technologies to deliver power, data or both. In some embodiments, power, data, or both, may be delivered simultaneously as a continuous complex waveform, as a pulsed waveform, as multiple overlapping waveforms, or combinations or variations thereof. The power and data may be delivered using the same or different wireless technologies.

The wireless technologies described herein may apply to not only electromagnetic (EM) waves, but also to sound waves, and/or other forms of periodic excitations (e.g., phonons). EM waves may include radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and/or gamma rays. Sound waves may include infrasound waves, acoustic waves, and/or ultrasound waves. The techniques described herein may simultaneously utilize multiple wireless technologies and/or multiple frequency spectrums within a wireless technology to deliver the power, data or both.

The wireless technologies may include dedicated hardware components to deliver power and/or data. The dedicated hardware components may be modified based on the wireless technology, or combination of wireless technologies, being utilized. For example, when applied to sound waves, the system employs microphones and speakers rather than antennas.

System Overview and Architecture

FIG. 1is a diagram illustrating an example wireless communication/power delivery environment100depicting wireless power delivery from one or more wireless transmitters101to various wireless devices102within the wireless communication/power delivery environment. More specifically,FIG. 1illustrates an example wireless power delivery environment100in which wireless power and/or data can be delivered to available wireless devices102.1-102.n having one or more power receiver clients103.1-103.n (also referred to herein as “wireless power receivers” or “wireless power clients”). The wireless power receivers are configured to receive wireless power from one or more wireless transmitters101.

As shown in the example ofFIG. 1, the wireless devices102.1-102.n are mobile phone devices102.2and102.n, respectively, and a wireless game controller102.1, although the wireless devices102.1-102.n can be any (smart or dumb) wireless device or system that needs power and is capable of receiving wireless power via one or more integrated power receiver clients103.1-103.n. Smart devices are electronic devices that can communicate (e.g., using WiFi) and transmit beacon signals. Dumb devices are electronic device are passive devices that may not communication (e.g., no Bluetooth or Wifi capability) and may not transmit a beacon signal. As discussed herein, the one or more integrated power receiver clients or “wireless power receivers” receive and process power from one or more transmitters/transmitters101.a-101.nand provide the power to the wireless devices102.1-102.n for operation thereof.

Each transmitter101(also referred to herein as a “charger”, “array of antennas” or “antenna array system”) can include multiple antennas104, e.g., an antenna array including hundreds or thousands of spaced-apart antennas, that are each capable of delivering wireless power to wireless devices102. Each transmitter101may also deliver wireless communication signals to wireless devices102. In some embodiments, the wireless power and wireless communication signals may be delivered as a combined power/communication signal. Indeed, while the detailed description provided herein focuses on wirelessly transmitting power, aspects of the invention are equally applicable to wirelessly transmitting data.

In some embodiments, the antennas are adaptively-phased radio frequency antennas and the transmitter101utilizes a novel phase shifting algorithm as described in one or more of U.S. Pat. Nos. 8,558,661, 8,159,364, 8,410,953, 8,446,248, 8,854,176, U.S. patent application Ser. Nos. 14/461,332 and 14/815,893. The transmitter101is capable of determining the appropriate phases to deliver a coherent power transmission signal to the power receiver clients103. The array is configured to emit a signal (e.g., continuous wave or pulsed power transmission signal) from multiple antennas at a specific phase relative to each other.

Additionally, the transmitter101may include a time delayed retro directive radio frequency (RF) holographic array that delivers wireless RF power that matches the client antenna patterns in three dimensional (3D) space (polarization, shape & power levels of each lobe). It is appreciated that use of the term “array” does not necessarily limit the antenna array to any specific array structure. That is, the antenna array does not need to be structured in a specific “array” form or geometry. Furthermore, as used herein he term “array” or “array system” may be used include related and peripheral circuitry for signal generation, reception and transmission, such as radios, digital logic and modems.

The wireless devices102can include one or more power receiver clients103(also known as a “wireless power receiver”). As illustrated in the example ofFIG. 1, power delivery antennas104aand data communication antennas104bare shown. The power delivery antennas104aare configured to provide delivery of wireless radio frequency power in the wireless power delivery environment. The data communication antennas are configured to send data communications to, and receive data communications from, the power receiver clients103.1-103.n and/or the wireless devices102.1-102.n. In some embodiments, the data communication antennas can communicate via Bluetooth™, WiFi, ZigBee™, or other wireless communication protocols.

Each power receiver client103.1-103.n includes one or more antennas (not shown) for receiving signals from the transmitters101. Likewise, each transmitter101.a-101.nincludes an antenna array having one or more antennas and/or sets of antennas capable of emitting continuous wave signals at specific phases relative to each other. As discussed above, each array is capable of determining the appropriate phases for delivering coherent signals to the power receiver clients102.1-102.n. For example, coherent signals can be determined by computing the complex conjugate of a received beacon signal at each antenna of the array such that the coherent signal is properly phased for the particular power receiver client that transmitted the beacon signal. The beacon signal, which is primarily referred to herein as a continuous waveform, can alternatively or additionally take the form of a modulated signal.

Although not illustrated, each component of the environment, e.g., wireless power receiver, transmitter, etc., can include control and synchronization mechanisms, such as a data communication synchronization module. The transmitters101.a-101.nare connected to a power source such as, for example, a power outlet or source connecting the transmitters to a standard or primary alternating current (AC) power supply in a building. Alternatively or additionally, one or more of the transmitters101.a-101.ncan be powered by a battery or via other power providing mechanism.

In some embodiments, the power receiver clients102.1-102.nand/or the transmitters101.a-101.nutilize or encounter reflective objects106such as, for example, walls or other RF reflective obstructions within range to beacon and deliver and/or receive wireless power and/or data within the wireless power delivery environment. The reflective objects106can be utilized for multi-directional signal communication regardless of whether a blocking object is in the line of sight between the transmitter and the power receiver client.

As described herein, each wireless device102.1-102.n can be any system and/or device, and/or any combination of devices/systems that can establish a connection with another device, a server and/or other systems within the example environment100. In some embodiments, the wireless devices102.1-102.n include displays or other output functionalities to present data to a user and/or input functionalities to receive data from the user. By way of example, a wireless device102can be, but is not limited to, a video game controller, a server desktop, a desktop computer, a computer cluster, a mobile computing device such as a notebook, a laptop computer, a handheld computer, a mobile phone, a smart phone, a battery or component coupled to a battery, a PDA etc. The wireless device102can also be any wearable device such as watches, necklaces, rings or even devices embedded on or within the customer. Other examples of a wireless device102include, but are not limited to, safety sensors (e.g., fire or carbon monoxide), electric toothbrushes, electronic door locks/handles, electric light switch controllers, electric shavers, etc.

Although not illustrated in the example ofFIG. 1, the transmitter101and the power receiver clients103.1-103.n can each include a data communication module for communication via a data channel. Alternatively or additionally, the power receiver clients103.1-103.n can direct the wireless devices102.1-102.n to communicate with the transmitter via existing data communications modules.

FIG. 2is a sequence diagram200illustrating example operations between a wireless transmitter101and a power receiver client103for commencing wireless power delivery, according to an embodiment. Initially, communication is established between the transmitter101and the power receiver client103, such as communicate via Bluetooth™, WiFi, ZigBee™, or other wireless communication protocols. The transmitter101subsequently sends a beaconing schedule to the power receiver client103to arrange beacon broadcasting and RF power/data delivery schedules with this and any other power receiver clients. Based on the schedule, the power receiver client103broadcasts the beacon. As shown, the transmitter101receives the beacon from the power receiver client103and detects the phase (or direction) at which the beacon signal was received. The transmitter101then delivers wireless power and/or data to the power receiver client103based the phase (or direction) of the received beacon. That is, the transmitter101determines the complex conjugate of the phase and uses the complex conjugate to deliver power to the power receiver client103in the same direction in which the beacon signal was received from the power receiver client103.

In some embodiments, the transmitter101includes many antennas; one or more of which are used to deliver power to the power receiver client103. The transmitter101can detect phases of the beacon signals that are received at each antenna. The large number of antennas may result in different beacon signals being received at each antenna of the transmitter101. The transmitter may then utilize the algorithm or process described in one or more of U.S. Pat. Nos. 8,558,661, 8,159,364, 8,410,953, 8,446,248, 8,854,176, and U.S. Provisional Patent Application Nos. 62/146,233 and 62/163,964. The algorithm or process determines how to emit signals from one or more antennas that takes into account the effects of the large number of antennas in the transmitter101. In other words, the algorithm determines how to emit signals from one or more antennas in such a way as to create an aggregate signal from the transmitter101that approximately recreates the waveform of the beacon, but in the opposite direction.

FIG. 3is a block diagram illustrating an example receiver300in accordance with an embodiment. The receiver300includes various components including control logic310, battery320, communication block330and associated antenna370, power meter340, rectifier350, beacon signal generator360and an associated antenna380, and switch365connecting the rectifier350or the beacon signal generator360to an associated antenna390. Some or all of the components can be omitted in some embodiments. Additional or fewer components are also possible.

The rectifier350receives (via one or more client antennas) the power transmission signal from the power transmitter, which is fed through the power meter340to the battery320for charging. The power meter340measures the total received power signal strength and provides the control logic310with this measurement. The control logic310also may receive the battery power level from the battery320itself or receive battery power data from, e.g. an API of an operating system running on the receiver300. The control logic310may also transmit/receive via the communication block330a data signal on a data carrier frequency, such as the base signal clock for clock synchronization. The beacon signal generator360transmits the beacon signal, or calibration signal, using either the antenna380or390. It may be noted that, although the battery320is shown for being charged and for providing power to the receiver300, the receiver may also receive its power directly from the rectifier350. This may be in addition to the rectifier350providing charging current to the battery320, or in lieu of providing charging. Also, it may be noted that the use of multiple antennas is one example of implementation and the structure may be reduced to one shared antenna, where the receiver multiplexes signal reception/transmission.

An optional motion sensor395detects motion and signals the control logic310. For example, when a device is receiving power at high frequencies above 500 MHz, its location may become a hotspot of (incoming) radiation. So when the device is on a person, the level of radiation may exceed a regulation or exceed acceptable radiation levels set by medical/industrial authorities. To avoid any over-radiation issue, the device may integrate motion detection mechanisms such as accelerometers, assisted GPS, or other mechanisms. Once the device detects that it is in motion, the disclosed system assumes that it is being handled by a user, and signals the power transmitting array either to stop transmitting power to it, or to lower the received power to an acceptable fraction of the power. In cases where the device is used in a moving environment like a car, train or plane, the power might only be transmitted intermittently or at a reduced level unless the device is close to losing all available power.

FIG. 4is a system overview diagram illustrating various embodiments and components possible, though other combinations and variations are possible. As shown, among other features, in some embodiments, the wireless power receiver can be in a form of an application specific integrated circuit (ASIC) chip, a mobile phone case, in a display device (e.g. computer monitor or television, which in turn may relay power to a nearby receiver103), packaged within a standard battery form factor (e.g. AA battery), etc.

Multiple Power Receiving Facilities on a Wireless Device

In a wireless power system, a wireless device typically has a single wireless power receiver with a single antenna for receiving power. An example wireless power receiver is shown inFIG. 3. InFIG. 3, antenna390receives wireless power and rectifier350rectifies the received RF power to direct current (DC), and then the DC power is integrated into the wireless device battery.

A wireless device with a single wireless power receiver and single antenna is limited in receiving power. For example, the current power per receiver for the wireless power system described inFIG. 3is approximately 1 watt RF received at each receiver antenna. However, the wireless device battery actually receives less than 1 watt of power after conversion from RF to DC. One solution to achieve greater power transfer is to deliver more power to the single receiver. Yet, it can be difficult to deliver high levels of wireless power to charge mobile electronic devices while staying within Federal Communication Commission (FCC) limits for RF signals.

In contrast, the disclosed system facilitates receiving wireless power implementing multiple wireless power receivers. The wireless power receivers can have multiple antennas or a single antenna. In some implementations, the system integrates power received at each antenna into the battery of the wireless device. As a sample use of the system, a control unit (e.g., a CPU) facilitates the process of receiving and regulating power from multiple receivers with multiple antennas (or a single antenna).

Alternatively, the system can be configured to power a particular portion of a wireless device with a particular wireless power receiver. The system can have a first wireless power receiver dedicated to powering a processor and a second wireless power receiver dedicated to powering a display. In general, whether the system is designed to use multiple wireless power receivers to charge a battery or use dedicated wireless power receivers to charge a component is a design consideration.

In order for the transmitter to send wireless power to multiple wireless power receivers, the transmitter can use a few, different techniques. One technique assumes that a single client has multiple antennas and the transmitter receives a beacon signal from a single antenna (or from all of the antennas). In other words, the transmitter has one logical or electrical address for each client regardless of the number of wireless power receivers and antennas that the wireless power receiver may have. Alternatively, a transmitter can assume each antenna is an independent client, even if the antenna is on the same wireless power receiver. In this implementation, the client registers with the transmitter multiple times with multiple addresses (e.g., multiple ZigBee™ addresses). The transmitter can then, e.g. schedule to transmit power to each client address independently for multiple beacon signals in a time division or frequency division manner.

In addition to receiving wireless power, the system has wireless power receivers with supplementary functionality. Wireless power receiver antennas can be configured to communicate using a wireless standard (e.g., WiFi, IEEE 802.11, ZigBee™, Bluetooth™) and transmit beacon signals. In some implementations, the system uses wireless power receivers that use an antenna or antennas to communicate via Bluetooth™, WiFi, ZigBee™, or other wireless communication protocols. Also, wireless power receivers can send a beacon signal from one or more of the same power receiving antennas. In general, instructions for communicating or transmitting beacon signals can be stored in memory, and these instructions can be executed by the CPU.

There are several advantages to the disclosed system. One advantage is that a wireless device can receive more wireless power from multiple wireless power receivers as compared to one wireless power receiver with a single antenna. Additionally, a mobile electronic device with multiple receivers and multiple antennas in different locations enables the device to receive electromagnetic (EM) waves with varying properties such as direction, polarity, phase, amplitude, or other properties of EM waves. For example, a mobile device laying on a table may have one wireless receiver with antennas positioned to receive wireless power from above the table and another wireless receiver positioned to receiver wireless power from below the table. Other advantages will become apparent to those having ordinary skill in the art upon reading this detailed description. All advantages may not be present in each implementation of the system.

FIGS. 5A-Care diagrams illustrating various examples of a transmitter delivering power to wireless devices having variable numbers of wireless power receivers. As shown inFIG. 5A, a transmitter101transmits EM waves to a wireless power receiver103, which is connected or coupled to a wireless device102. As described above inFIG. 1, a wireless device102can be a mobile phone, laptop, or other mobile electronic device.

InFIG. 5B, a transmitter101transmits EM waves to wireless power receiver103.1, which is connected or coupled to wireless device102.1, and wireless power receiver103.2, which is connected or coupled to wireless device102.2. As described above with respect toFIG. 1, wireless power receivers103.1and103.2can each have a single antenna for receiving power or have multiple antennas for receiving power. In general,FIG. 5Bdemonstrates that transmitter101is configured to transmit wireless power to multiple devices, and these multiple device may be located in different parts of a space (e.g., one in a corner of a kitchen and the other 10 feet away from the corner).

Importantly, inFIG. 5C, transmitter101is configured to transmit EM waves to multiple wireless devices, each with multiple wireless power receivers. As shown inFIG. 5C, wireless devices102.1and102.2have multiple wireless power receivers103.1a-1nand103.2a-2n, respectively. The wireless power receivers103.1a-1nand103.2a-2nare coupled or connected to the wireless devices102.1and102.2, respectively. Also, the wireless power receivers are located at different locations on the wireless devices102.1and102.2. Because the wireless receivers are located in different locations, the wireless device can receive EM waves with varying properties. In other words, a transmitter can emit EM waves with various properties (e.g., direction, polarity, frequency, strength, phase), and these waves can be reflected or changed during in the transmission path (e.g., reflection from a wall or object). And because the wireless device has multiple wireless receivers with multiple antennas positioned in different locations it is more likely to receive power than a single wireless receiver with a single antenna. The details of a wireless power receiver103are described below in more detail with respect toFIGS. 7A-CandFIGS. 8-11.

Building onFIG. 5C,FIG. 6is an example of a mobile device102with multiple wireless power receivers103.1a-c. In some implementations, the wireless receivers103.1a-care spaced at the far corners of the device for various reasons, such as to enable receiving power if some of the antennas in a receiver are blocked. For example, a device set on its back on a thick table may have no path for RF energy to reach an antenna in the middle-back of the device. At least some antennas should receive power in such a condition. In general, the number of wireless power receivers can increase or decrease to optimize the cost and efficiency of the mobile device, depending upon design constraints. For example, depending on the power demands of a mobile device, the mobile device can include more or fewer wireless power receivers. More details regarding the internal components of a wireless power receiver are described below. Each of the examples described below can be integrated into a wireless device to increase the number of wireless receivers.

Moving toFIGS. 7A-7C, the Figures together shown an example schematic diagram of a circuit for the wireless power receiver. The schematic diagram is spread overFIGS. 7A, 7B, and 7Cas shown with connecting points “A” and “B” inFIG. 7A; “A,” “B,” “C,” and “D” inFIG. 7B; and “C” and “D” inFIG. 7C. As a broad overview, the circuit includes elements such as capacitors, op-amps, inductors, lead wires, and grounds. These components can be varied to meet design specifications. For example, some capacitors can have a capacitance of 1 microfarad or 1 picofarad, and inductors can have inductance of 1 millihenry. Voltages in the circuit can be 0 to 5 volts (or more) with a typical 3.3 volts to open a gate to send a beacon signal. Resistors can have 20 to 200 Ohms (or more) resistance ratings. But overall, actual values of components shown inFIGS. 7A-7Cdepend upon the implementation details and design constraints.

Starting on the left side ofFIG. 7A, an antenna705receives wireless power or data. While one antenna is shown inFIG. 7A, several antennas can be included in the circuit, where the antennas would be connected to similar components as the antenna705. Once the antenna705receives power, the wireless power moves to sensing unit710. Sensing unit710senses if an antenna is receiving power. A sensing unit710can be a directional coupler or other RF detector (also referred to as a “detection unit”). As shown inFIG. 7A, an input unit725is connected or coupled to the sensing unit710. The input unit725may be simple logic or circuitry configured to send information regarding the received wireless power to another part of the system such as the CPU.

Regarding sensing information for wireless power, the sensing unit710receives a small portion of the wireless power and notifies the wireless device that power has been received. The CPU in the wireless device can use the sensed wireless power information to determine which antennas are receiving power and how much power is received. In some embodiments, the CPU can store this data in memory and send it to a transmitter, database, or cloud storage device for further analysis (e.g., to determine which antennas are generally better for receiving power). As a sample use of sense information, the transmitter can determine which transmitting antennas are efficiently sending power to which receiving antennas based on sense information, and the transmitter CPU can use this information to optimize the transmission of wireless power.

After sensing that RF power is received at antenna705, the circuit inFIG. 7Adetermines a path for the power. As shown inFIG. 7A, switching unit715can switch the antenna from a communication or beacon mode to rectifying mode by applying a voltage to the switching unit715(“RF_switch_RECTIFIER,” “V2”). As V2is applied to the switching unit715, the power is directed towards “J2” where it enters an RF rectifier720. A switching unit715can be referred to as a control unit and it can be implemented in an integrated circuit or on an ASIC. The RF rectifier720converts the RF power to DC, and the DC power can directly enter a battery. Alternatively, the circuit can further process the power as described inFIGS. 8-10below.

Also, the circuit inFIGS. 7A-Ccan use antenna705to communicate or send the beacon signal. As shown inFIG. 7A, if a voltage (e.g., V1by “RF SWITCH COMM”) is applied to switching unit715, the circuit can communicate using a known signal type (e.g., WiFi, Bluetooth™, ZigBee™). The “A” point onFIG. 7Ashows where communication signals are transmitted and received. Additionally, if a voltage (e.g., V3) is applied to switching unit715, the beacon signal can transmitted from antenna705as described in more detail below with respect toFIG. 7C.

Moving toFIG. 7B, the circuit can send communication from point “A” to point “C”. While not shown inFIG. 7B, point “C” is connected to an integrated circuit for communication such as communicate via Bluetooth™, WiFi, ZigBee™, or other wireless communication protocols. Before the signal is sent to the respective communication chip, a filter can remove the data from the wireless power signal. More details regarding the filter and circuit as described inFIG. 10below.

Staying withFIG. 7B, a central control unit (e.g., a processor) can send a pulse and amplitude enabling signal (“PA_Enable”) to enable a beacon signaling sequence. Once the “CLOSED” portion of circuit7B opens (as shown in the middle-upper portion ofFIG. 7B), a voltage reaches two op-amps730. The two-op amps730amplify the beaconing signal coming from “D”. A CPU or ASIC can generate the beacon signal that comes from “D”. After the beaconing signal is amplified, antenna705transmits it.

As shown inFIG. 7C, another switch735can active the beacon signaling path shown inFIG. 7C. A CPU can send a “RF Switch Beacon” signal into switch735, and switch735can flip and cause “RF_P” to enter the circuit. “RF_P” can be a pulse with a beacon signal.

Overall,FIGS. 7A-7Cdescribe a general integrated circuit schematic for using an antenna to receive power, communicate information, and transmit a beacon signal. As disclosed below,FIGS. 8, 9, and 10describe specific implementations of the integrated circuit described inFIGS. 7A-7Cwith various embodiments. Specifically,FIGS. 8 and 9are block diagrams of an application-specific integrated circuit (ASIC) for receiving wireless power.FIGS. 10 and 11disclose an ASIC chip that is connected or coupled to a CPU in a wireless device.

FIG. 8is an example of a block diagram illustrating a wireless power receiver (also known as a “client chip” or “receiver chip”). As shown inFIG. 8, the client chip can include: “N” RF detectors (where “N” is a natural number), “N” RF rectifiers, an MPP (maximum power point tracking “MPPT”, also referred to as the “MPP”) for each “N” RF rectifier, an N-channel analog multiplexer (MUX), a buck-boost converter, an analog to digital converter (ADC), antenna804for sending beacon signals, “N” antenna inputs806for receiving wireless power, a register bank, ground connections, a frequency comparer808, and input/output connections. As illustrated, an RF rectifier can be coupled to an MPP loop to optimize power delivery. For example, the MPPT loop can communicate with a buck-boost converter to provide the client with constant voltage/current in an efficient manner. Additionally, as shown inFIG. 8, one antenna can be transmitting a beacon signal as another antenna concurrently receives RF power. Also, while not shown inFIG. 8, a device can receive a sensed RF value from an RF detector and based on the received RF power being low (e.g., less than 0.02 watts), the device (e.g., using a CPU) can switch the antenna off (e.g., with a switch connected to the antenna).

Also, the client chip receives a strength signal indicator (RSSI, or other similar signal) via the received signal and ADC. The RSSI can serve multiple purposes such as identifying clients that are not receiving enough power to rectify a significant amount of DC, or identifying clients who are receiving a very high power and should probably have their duty cycle reduced. In general, the RF detector, MPP, N-MUX, ADC, and RSSI components communicate with the CPU (not shown) to determine how to optimize power received by the client chip.

While a buck-boost converter is shown inFIG. 8, other converters, such as a flyback converter can be used to optimize the power delivery. Also, while the client chip shows “N” number of antennas, and more antennas generally means the chip can receive more power, the number of antennas may be reduced to lower cost of chip design. Also, to optimize power delivery to the client, short traces can be used and the number of resistors can be limited to lower the loss of power (i.e., improve efficiency). Additionally, antennas should be placed close to RF rectifiers to reduce impedance. Also, if all antennas emit the beacon signal then spacing can vary between antennas because the transmitter can detect the beacon signal from all antennas and send power back to all antennas. Alternatively, if only one antenna emits the beacon, the other antennas should be within ¼ wave length (˜3 cm) of the beacon emitting signal.

Also,FIG. 8includes a register bank. The register bank can store values such as a received RSSI value, MPP value, RSSI channel select, PA gain control, PA source select, and prescaler divider control. These values can be saved in the register can used by a processor. Additionally, a processor can access the register bank and send the stored values to another device or network.

Similar toFIG. 8,FIG. 9is another example block diagram illustrating a schematic of a similar client chip. The client chip receives, rectifies, and converts RF power into DC voltage/current. A client chip can use the DC voltage/current received from a client chip to power the client, or it can use the DC voltage/current to store power in a battery. Also, a client chip can couple to a single antenna905(e.g. to transmit the beacon signal), and couple to multiple antennas910a-n(e.g., four antennas to receive power). The client chip includes an RF rectifier930a-nfor each antenna, a maximum power point tracking (MPPT, or also referred to as the “MPP”)935a-nloop, a buck-boost converter940, a transceiver switch960, an RF detector925, a PLL945, and a memory950. In general, multiple client chips can be placed in a single wireless device as shown inFIG. 6.

In some implementations, the client chip transmits a beacon signal, and the beacon signal includes information used to compute the location of the client, as described above inFIG. 1. The client chip can transmit beacon signaling to the wireless charger (e.g., in wireless charger101inFIG. 1) using an RF signal input, PLL945, power amplifier920, transceiver switch960, and antenna905. The beacon signal encoding process and algorithm may be that described in the applicant's U.S. application Ser. No. 14/956,673, filed Dec. 2, 2015, titled TECHNIQUES FOR ENCODING BEACON SIGNALS IN WIRELESS POWER DELIVERY ENVIRONMENTS, which is hereby incorporated by reference in its entirety.

In some implementations, the memory950on the client chip stores the power management policy for the client device (e.g., the power management integrated circuit (PMIC) has been replaced or supplemented with the client chip). In these implementations, the client chip can supply power directly to the client device (e.g., in the battery or into the client's system). Alternatively, a client may have a proprietary PMIC, and the client chip may be coupled to the PMIC. In these implementations, the client chip supplies power according to the specification provided by the manufacturer of the PMIC, and the client's PMIC handles the management of this power (e.g., pins and traces can be used to allow the client chip and PMIC to communicate and transfer power).

While not shown inFIG. 8 or 9, a client chip can support a wide range of applications with different power requirements starting from several hundred milli-watts (mW) up to several watts of power. Also, the client chip can include an on-chip temperature sensor to protect the chip from overheating or damage.

Moving toFIG. 10,FIG. 10is an example of a power receiving client. As shown in solid lines, RF signals combine right after being received by antennas and then the power is rectified. The efficiency of this alternative can depend on if there is constructive or deconstructive interference when combining RF power after the antennas receive power signals. Another option, as shown with broken lines, RF signals are combined after the power is rectified. The receiver can employ one of two ways to achieve parallel combination: either by combining the signals at RF in the front end of the client or by combining the signals at DC after conversion.FIG. 10also includes a data communications unit (bottom left), which can be used to communicate with a network or transmitter over WiFi or Bluetooth™.

FIG. 11is another, similar example of a power receiving client with other client technology. This example is different than the examples above because, in part, this client includes a Bluetooth™ chip. As shown inFIG. 11, the client can have antennas that receive power and data (e.g., Bluetooth™ data). In some implementations, the power and data signals can be at the same frequency, and the antennas of the client may pick up both a power signal and a data signal. In order to separate these signals, as shown inFIG. 11, the client can include a filter to separate power from data even if the signal is the same frequency. After the signal is filtered, power can be sent to the RF rectifier and converted to DC power. Additionally, a client can communicate via Bluetooth™, WiFi, ZigBee™, or other wireless communication protocols

In some implementations, a data power filter may be used to separate the signals. Methods and systems for separating or filtering these types of signals is described in the applicant's U.S. application Ser. No. 14/926,014, filed Oct. 29, 2015, titled TECHNIQUES FOR FILTERING MULTI-COMPONENT SIGNALS, which is hereby incorporated by reference in its entirety. Data signals can be sent to the Bluetooth™ chip for appropriate transmission. Similar to other examples of chips and clients described above, this client can use one or more channels in parallel to receive RF power and convert it into DC using the MPPT algorithm for optimization. In some implementations, DC power can be used to charge a battery on the client device. This client is also capable of sending a beacon signal at 2.4 GHz because it has a PLL/Frequency Synthesizer and power amplifier integrated into it, which can be used to send a beacon with the client's location to a wireless charger. The frequency of operation is not limited to just the 2.4 GHz but can also operate in other ISM frequency bands or frequency bands outside of ISM.

Also, while not shown inFIG. 11, WiFi technology can be used in a similar method described in the example above. For example, if a client has a WiFi chip and a client chip, a filter can be used on the client chip to separate the data signal from the power signal even if the signals are sent at the same frequency.

Example Computer Systems

FIG. 12depicts a block diagram illustrating example components of a representative client (e.g., mobile device, tablet computer, category controller, maintenance controller, etc.)1200in the form of a mobile (or smart) phone or tablet computer device. Various interfaces and modules are shown with reference toFIG. 12, however, the mobile device or tablet computer does not require all of modules or functions for performing the functionality described herein. It is appreciated that, in many embodiments, various components are not included and/or necessary for operation of the category controller. For example, components such as GPS radios, cellular radios, and accelerometers may not be included in the controllers to reduce costs and/or complexity. Additionally, components such as ZigBee™ radios and RFID transceivers, along with antennas, can populate the Printed Circuit Board.

FIG. 13depicts a diagrammatic representation of a machine, in the example form, of a computer system1300within which a set of instructions, for causing the machine to perform any one or more of the methodologies discussed herein, may be executed. The computer system1300can be representative of any computer system, server, etc., described herein.

In the example ofFIG. 13, the computer system1300includes a processor (CPU), memory, non-volatile memory, and an interface device. Various common components (e.g., cache memory) are omitted for illustrative simplicity. The computer system1300is intended to illustrate a hardware device on which any of the components depicted in the example ofFIG. 1(and any other components described in this specification) can be implemented. The computer system1300can be of any applicable known or convenient type. The components of the computer system1300can be coupled together via a bus or through some other known or convenient device.

The processor may be, for example, a conventional microprocessor such as an Intel x86-based microprocessor. One of skill in the relevant art will recognize that the terms “machine-readable (storage) medium” or “computer-readable (storage) medium” includes any type of device that is accessible by the processor.

The memory is coupled to the processor by, for example, a bus. The memory can include, by way of example but not limitation, random access memory (RAM), such as dynamic RAM (DRAM), static RAM (SRAM), flash RAM, etc. The memory can be local, remote, or distributed.

The bus also couples the processor to the network interface device. The interface can include one or more of a modem or network interface. It will be appreciated that a modem or network interface can be considered to be part of the computer system. The interface can include an analog modem, ISDN modem, cable modem, token ring interface, satellite transmission interface (e.g. “direct PC”), or other interfaces for coupling a computer system to other computer systems. The interface can include one or more input and/or output devices. The I/O devices can include, by way of example but not limitation, a keyboard, a mouse or other pointing device, disk drives, printers, a scanner, and other input and/or output devices, including a display device. The display device can include, by way of example but not limitation, a liquid crystal display (LCD), OLED, or some other applicable known or convenient display device. For simplicity, it is assumed that controllers of any devices not depicted reside in the interface.

CONCLUSION