Wireless power

An apparatus can receive and transfer data and energy between adjacent apparatus in a chain. Each apparatus comprises an input antenna for receiving an input signal which is tuned and impedance matched for a receiver and demodulator in a control circuit. The demodulated signal is provided as input to a transmitter module to create an output signal. The input signal is then impedance transformed to generate a sufficient voltage to energize a power supply which charges a battery. The input signal and the output signal can be a radio signal, a magnetic induction signal, or a combined radio and magnetic induction signal. A controller in the control circuit monitors the condition of the battery and power supply and controls a switch operable to selectively power parts of the apparatus dependently upon their monitored condition.

CROSS REFERENCE TO RELATED APPLICATIONS

This patent application is a national phase entry under 35 U.S.C. §371 of PCT International Patent Application PCT/EP2011/064002, filed Aug. 13, 2011, designating the United States and published in English as international Patent Publication WO2012/069218 A1 on May 31, 2012, which claims the benefit, under Article 8 of the PCT, of U.K. Patent Application No. GB 1013590.3, filed Aug. 13, 2010, the entire disclosure of each of which is hereby incorporated herein by this reference.

FIELD OF THE INVENTION

The present invention relates to data wireless transfer between equipment. It further relates to data transfer where the total energy required is minimized.

BACKGROUND OF THE INVENTION

Digital data is now commonly transferred within buildings and dwellings. A non exhaustive list, to which many others could be added, includes instructional and informational digital signals provided between items of computer equipment, control and feedback digital signals provided to and from appliances, and control and content defining digital signals provided to, from and between media equipment such as television displays and recorders, video players, and audio playing and recording equipment.

It is known to employ many different types of medium for transfer of digital data. Wire connection is popular. Twisted pair wires can be used, as in Ethernet cables, or co-axial cable, multi screened cable or any other sort of wire or cable. Wires and cables are not without their disadvantages. Wires and cables have the disadvantage of being lossy, particularly at higher frequencies, are not immune from crosstalk, and, due to inherent inter-conductor capacitance, can impose a maximum and relatively low bandwidth or data rate on any signal. Another problem with wire or cable data transfer links is the existence of inherent characteristic impedance which has to be accurately matched by terminations if reflections in the wire of cable are to be avoided. Reflections can destroy the intelligibility of digital signals and limit the useful distance a digital signal can be propagated. Yet another disadvantage of wires and cables is the immovability of the equipment to which they are attached. The route of equipment wires or cables must be planned and laid out free from obstruction to humans or animals before any move can be made. The aesthetics of cables and wires can also leave much to be desired. When using wire or cable, many considerations, all of which must be simultaneously correct, must be taken into account. The present invention seeks to provide a solution to the many problems encountered when using wires and cables, allowing for easy movement of equipment with none of the myriad matching and bandwidth difficulties.

Some equipment employs fibre optic cables in a domestic or business setting. Fibre optic cables can provide ultra high bandwidths. However, the cables are once again fixed, making movement of the equipment to which they are attached limited, difficult or impossible. Joining fibre optic cables to a terminal or to each other is a precision operation, requiring high skills of any person setting up, connecting or repairing any system. By avoiding some of the problems of wires or cables, fibre optics introduces another set of difficulties. The present invention seeks to avoid problems associated with fibre optic cables, providing instead a solution allowing ready connection with no high skill levels being required.

Wireless data transfer has also been used. As only two examples, Bluetooth (a registered Trademark) is a system of radio transmitters and receivers used, typically, to provide services from remotely connected equipment in a mobile telephone. WiFi is a radio bidirectional coupling protocol using 2.4 GHz or 5 GHz used to couple portable computer equipment to local transceivers providing access to the Internet of any other network. A difficulty with any radio coupling, which is also not unknown with wire, cable or fibre optic coupling, is the relative power requirements of terminal equipment, necessitating at least a fresh battery and possibly a mains power supply for sustainability. This is wasteful of energy, wastes potentially toxic battery and power supply materials and their attendant manufacturing carbon dioxide emissions, is not “green” (a casual term for “environmentally conservational”). The present invention seeks to provide energy efficiency in data transfer. The present invention further seeks to provide for energy transfer in accompaniment with data transfer.

Wireless transfer of energy is known using contact pads whereon an apparatus, such as a rechargeable toothbrush, razor, music player or similar apparatus is placed to allow recharging of an internal battery using a magnetic core within the pad. The core within the pad carries an AC field which can be magnetically coupled to a secondary core within or connected to the apparatus. When the apparatus is placed on the pad, the AC magnetic field induces voltage on a secondary winding on the secondary core. The secondary winding provides charging power fort the battery. It is also known to connect an antenna to the outside glass of a vehicle and feed radio frequency power and energy by means of a capacitive coupling immediately behind the connection point inside the vehicle glass. Both these energy and possible data coupling solutions are extremely short range, and involve intense fields which can be a potential hazard.

BRIEF SUMMARY OF THE INVENTION

The present invention consists of an apparatus for receiving data signals, the apparatus comprising: first antenna means, operable to receive an input signal modulated to include the data signal; means operable to receive and decode the radio signal to provide a decoded data signal; and means operable to convert the input signal into electrical energy for powering the apparatus.

The invention also provides that the apparatus can comprise: means to generate an output radio signal modulated with the decoded data signal; and second antenna means operable to transmit the output radio signal.

The invention also provides that the means operable to convert the input radio signal into electrical energy can comprise; means for converting the signal from the first antenna means into a DC voltage; battery means; and a charger, operable to charge the battery means from the DC Voltage.

The invention also provides that means for converting the signal from the first antenna means into a DC voltage can comprise an antenna impedance matcher operable to match the impedance of the first antenna means to a notional load; can comprise impedance transformation means operable to transform the impedance of the notional load to provide an un-rectified voltage sufficient for rectification; and can comprise rectification and smoothing means operable to provide the DC voltage.

The invention also provides that the battery means is operable to provide power to the apparatus in the absence of the DC voltage, and the DC voltage is employable to contribute power to apparatus when the input radio signal is present.

The invention also provides that the apparatus comprises resting means, operable to set the apparatus into a low power mode when the input radio signal is below a predetermined strength, the rest mode conserving charge in the battery means.

The invention also provides that the apparatus can have, as the input signal, a radio signal, a magnetic induction signal, or combination of a radio signal and a magnetic induction signal.

The invention also provides that the output signal can be a radio signal, a magnetic induction signal, or a combined radio signal and a magnetic induction signal.

For a more complete understanding of the present invention, reference is made to the following detailed description and accompanying drawings. In the drawings, like reference characters refer to like parts throughout the views in which:

DETAILED DESCRIPTION

Attention is first toFIG. 1, showing a chain of data and energy transfer apparatus5coupled together by data signals7, being radio or magnetic induction signals, or both, or mixed. Data receiving powered apparatus9can be coupled to some or all of the data and energy transfer apparatus5in the chain to receive power via the data signals. One data and energy transfer apparatus5A is at the head of the chain, and does not need to receive an energizing data signal7, but rather derives its energy from another power source such as a mains derived power supply, and its data signals from a data source (not shown).

So long as the cumulative energy loss between data and energy transfer apparatus5down the chain is insufficient to prevent the ability of the penultimate data and energy transfer apparatus5in the chain to provide an outgoing data signal to the final data and energy transfer apparatus5in the chain to power the data receiving powered apparatus9, the chain will sustain its complete function.

The chain ofFIG. 1can also be used to deliver useable and informational data to the data receiving powered apparatus9coupled to the data and energy transfer apparatus5.

Not all of the data receiving powered apparatus9needs necessarily to receive data, and not all of the data receiving powered apparatus9needs to receive power. Some of the data receiving powered apparatus can receive both power and data.

Likewise, not every data and energy transfer apparatus5needs to have a data receiving powered apparatus9coupled thereto, but can serve merely as a link in the chain.

Attention is next drawn toFIG. 2, which shows detail of the data and energy transfer apparatus5of the chain ofFIG. 1and is an example of one possible embodiment of data and energy transfer apparatus5

In this example, radio is used. A first antenna10an receive an input radio signal12which is provided to an antenna tuner14to resonate the first antenna10and cause it to have an impedance suitable to provide a signal to an input signal line16to deliver the data signal to a control circuit18.

Output from the antenna tuner14is also provided to an impedance transformer20which increase the voltage delivered by the input radio signal12until, hopefully, it is sufficient to provide drive to a DC supply24. A voltage sufficiency line22provides indication to the control circuit18when the transformed voltage is large enough to drive the DC power supply24.

The DC power supply24delivers charge to a battery26which delivers a positive power input28and a negative power input30to provide energizing power to the control circuit18.

The control circuit18is operable, when conditions are right, to drive a second antenna32to emit an output radio signal34. The input radio signal12and the output radio signal34each contain data. The data from the input radio signal12is provided to the control circuit18via input signal line16, the data then being recovered by demodulation within the control circuit18. Data (not necessarily identical to the demodulated data) is modulated onto the output radio signal34.

The power delivered by the input radio signal12is delivered to power the control circuit18, and also to deliver power to any other device or appliance which is coupled (not shown inFIG. 1) to the control circuit.

The output radio signal is intended for reception by a further apparatus, similar to that show inFIG. 1. A chain ofFIG. 1apparatus can thus be formed. Of course, if a particularFIG. 1apparatus is the last in a chain, there is no need to emit an output radio signal34.

As will be made clear later, the first and second antennas can have various forms for radio signals. The apparatus can also operate using inductive magnetic fields operating at high frequencies.

Those skilled in the art will be aware of other schemes of arranging an antenna or magnetic field induction coil snatching to deliver data and sufficient voltage to drive a DC power supply24. Such other schemes are to be found, as just one example, in the publications of the Radio Society of Great Britain (RSGB) and of the American Radio Relay League (ARRL).

InFIG. 2, a data receiving powered apparatus9is shown in broken outline, not being a necessary part of the data and energy transfer apparatus5not being necessarily coupled to the control circuit18. The data receiving powered apparatus9is shown coupled to the control circuit16via a power and/or data coupling36.

Attention is next drawn toFIG. 3, a schematic block diagram illustrative of possible exemplary contents of the control circuit18.

A controller38is in overall command of the control circuit. A receiver and demodulator40receives the input from the first antenna10and delivers a data signal to the controller38. A transmitter module42receives instructions, control signals and data signals from the controller38and provides input to the second antenna32to send the output radio signal34. A power and data switch44is controlled by the controller38to determine how and where energy and data will be provided around and from the control circuit. The controller38also monitors the battery26positive power line28to assess the state of charge of the battery26and monitors the voltage sufficiency line22to determine whether or not the battery26can be charged.

Attention is next, drawn toFIGS. 4 and 5, whereinFIG. 4is a perspective view of an exemplary magnetic antenna, suitable for use with radio signals or magnetic induction fields andFIG. 5is an exemplary circuit diagram illustrating tuning and impedance matching in the antenna ofFIG. 4.

A main coil46, preferably would on a former48, is tuned to resonance by a variable capacitor50. The resonance frequency is, typically, several megahertz to several tens of megahertz, but can be of any value. Taps52are arranged along the main coil48to provide a variety of voltages and impedances relative to a has terminal54. Mutual Inductance coupled loops and coils56can be provided, with the same or a lesser diameter that the main coil48. These are particularly of use in providing a drive feed impedance for the transmitter module42. Not shown, but also of use, is the inclusion of low loss magnetic rods, such as ferrite, within the main coil48, giving a greater effective area to the magnetic antenna because of relative permeability effects. Those skilled in the art will be aware of other means of feeding and impedance/voltage transformation that can be used with magnetic and magnetic induction antennas.

Attention is next drawn toFIGS. 8 and 7, in whichFIG. 6shows an antenna suitable for high speed data transfer andFIG. 7shows a combined magnetic and radio antenna.

FIG. 6shows a single, exemplary high data transfer speed antenna. A yagi-uda array58is well known for reception and transmission of Win signals giving high data rates in the 24 or 5 GHz frequency range. Yagi-uda arrays can be used on almost any frequency, their dimensions being scaled in inverse proportion to the frequency used. They offer high gain and accordingly narrow beam width, useful for energy transfer. A driven or receiving element60is backed by one or more parallel slightly longer spaced reflector elements62and fronted by a plurality of slightly shorter parallel spaced director elements64to have maximum sensitivity and beam power in the direction along an axis66from the driven or receiving element60. For greater sensitivity and directivity, vagi-gda arrays may be stacked side by side, above one another, or both.

Use is not restricted to Yagi-uda arrays. Antennas used can include, but are not restricted to: skeleton slat antennas and arrays; keyhole antennas and arrays; parabolic antennas and arrays, rhombic antennas and arrays; quad antennas and arrays; delta loop antennas and arrays; and a host of other possibilities.

FIG. 7shows a combined antenna, employing, in this example, both the antenna ofFIG. 8allowing high speed data transfer, an a magnetic antenna fromFIGS. 4 and 5, where additional energy transfer may be required.

In practise, any type of antenna can be used, and any combination of two or more antennas employed.

FIG. 8is a block diagram showing how magnetic and radio antennas can be combined.

FIG. 8is similar toFIG. 2, and like numbers denote like items. Magnetic antennas70, similar to those shown inFIGS. 4 and 5, are used for energy transfer because of the enhanced ability of inductive magnetic fields to transfer energy at safe field strengths compared with radio waves. On the other hand, magnetic antennas for inductive radio frequency (RF) magnetic fields have a lessened data carrying capacity. Accordingly, the first10and second82antennas are of, for example, the type shown inFIG. 7, having high speed data carrying capacity.

Attention is next drawn toFIG. 9, a block diagram illustrating how plural chains can be employed.

Within a building, home, site or institution, plural chains5A5B5C5can be established and used. The chains5A5B5C5can be functionally separated from one another by selection of field orientation, frequencies, field types (magnetic inductive or radio) and by physical separation. A head of chain data and energy transfer apparatus5A5B5C is located at the head of each of the plural chains and other data and energy transfer apparatus5are disposed in each of the chains. The chains can be of different lengths. The chains can be operated at the same time, or at separate times.

The controller38in the control unit18can organize the operation of the other data and energy transfer apparatus5.

In controlling a control circuit18, the controller has many options. Potentially, the battery26has the ability to power initial control circuit18activity. However, if the battery is flat, operation is not possible and it is impossible for the control circuit18to function in the absence of power from the power supply24. Assuming the control circuit18is powered, either by the battery or by the power supply, a first priority is to attend to the battery26charge so that post power supply24operation can occur. A first option is to check if the battery26is fully charged, and only to provide power and data through the control circuit18once the battery26is fully or at least partially charged.

Another priority is to check whether or not operation is for a final data and energy transfer apparatus5. If this is the case, there is no need to operate the transmitter module42. This, in one example, can be communicated to a particular data and energy transfer apparatus5by addressing transferred data to that data and energy transfer apparatus5. This addressing can also indicate whether or not the data is to be transferred to the coupled data receiving powered apparatus9.

Another priority is to determine if a particular data and energy transfer apparatus5is next in the chain. If a mutual bidirectional signalling capacity is available, this can be achieved by handshaking. If the transmitting frequency of the next in chain data and energy transfer apparatus5is tuned, handshaking data can be exchanged between data and energy transfer apparatus5for mutual authentication.

Finally, how is data provided? The head if chain data and energy transfer apparatus5A5B5C can generate data to a particular of all data and energy transfer apparatus5in a chain if energy provision to apparatus and battery26charging is solely desired. The data and energy transfer apparatus5address data can be combined with usable data from an exterior source to direct the exterior source data to a particular data and energy transfer apparatus5or coupled data receiving powered apparatus9.

Each chain5A5B5C5can have a common head of chain unit, common to all of the chains5A5B5C5which is operable to monitor messages passing up and down each chain5A5B5C5to determine what units5A5B5C5are functional, the condition of their function, the power consumption, and a host of other data. The common head of chain unit can comprise a screen to display the state of the units5A5B5C5. The screen can be a touch screen to control the units5A5B5C5. The system can comprise just one common head of chain unit, omitting the other head of chain units5A5B5C. Equally, the other head of chain units can monitor unit5A5B5C5functions and can comprise screens as the common head of chain unit. Down chain units5can also have screens and monitoring and control functions.

One application for the invention is to provide power within a motor vehicle, where data must be generated in a stand alone manner within a chain head unit5A,5B,5C or within a common chain head unit.

The invention has been described with reference to radio waves and magnetic induction fields. It is to be appreciated that the invention also extends to employment of all types of fields, including but not limited to acoustic and ultrasonic fields, electric fields, and indeed any other type of field for which a receiving antenna or transducer and a transmitting antenna or transducer can be provided.

The invention has been described and explained in terms of embodiments and examples. Those skilled in the art will be aware of differences and variations which can be employed without departing from the invention as defined by the following Claims.