Patent Application
20180138754
The present invention relates to a wireless communication device and method. In particular, the present invention relates to a wireless communication device and method allowing for RF energy harvesting.
The interest in energy efficiency of communication networks has been rekindled in the last decade with the growing concern about global warming and the increasing proportion of the information and communication technologies (ICT) within the global carbon footprint. The world's ICT ecosystem uses about 1500 TWh of electricity annually, equal to all the electric generation of Japan and Germany combined. ICT is predicted to increase its energy consumption every year, as it increasingly penetrates all areas of human activity through new technologies such as cloud computing, mobile internet, internet of things, and new devices such as smart phones, tablets and smart watches. To reduce the carbon footprint of ICT, increasing the energy efficiency in acquisition, processing and distribution of information over wired and wireless networks, has become a major challenge for researchers. Communication systems already take up some 25% of the energy used by ICT. Therefore, it is of utmost importance that both wired and wireless communication devices are designed for optimal energy efficiency, without sacrificing quality of service or performance.
Recently energy harvesting (EH) has emerged as a powerful complementary technology for wireless networks to extend the lifetime of the network and to reduce the dependence on the power-grid and battery. Mechanical energy, electrical or magnetic fields, light, or temperature differences in the environment can be harvested by converting them into energy for powering sensors using piezoelectric, radio frequency, thermoelectric, inductive coupling, wind, or solar harvesting technologies.
In today's connected world, where wireless networks are ubiquitous, ambient radio frequency (RF) energy is everywhere, presenting itself as a potential energy source for energy-constrained wireless networks. There are several advantages of RF energy harvesting compared to other potential sources of ambient energy: i) it can be harvested using the existing antennas of the nodes, ii) RF energy can be intentionally transmitted from remote charging stations, and hence, the receivers are less dependent on the randomness of the environment for their operation, such as solar energy harvesters not functioning during night.
Some solutions for optimizing the battery usage in a wireless communication device are known. US2012/0210325, for instance, discloses a wireless communication device including a smart task scheduler for extending the lifetime of the battery of the wireless communication device. This approach, however, allows only a limited optimization and once the battery of the wireless communication device is empty, the device is “out of service”.
US2013/0106352 discloses a USB battery charger allowing to recharge a wireless communication device whenever needed, i.e., opportunistically. However, such a US battery charger also needs to be recharged beforehand.
Thus, there is a need for an improved wireless communication device and method, in particular an improved wireless communication device and method suitable allowing for RF energy harvesting.
It is an objective of the invention to provide an improved wireless communication device and method, in particular an improved wireless communication device and method suitable for RF energy harvesting.
This objective is achieved by the subject matter of the independent claims. Further implementation forms are provided in the dependent claims, the description and the figures.
According to a first aspect the invention relates to a wireless communication device configured to communicate with an energy distributor, in particular a base station or a further wireless communication device, the wireless communication device comprising: a rechargeable energy storage configured to supply the wireless communication device with energy to maintain operation of the wireless communication device; a transmitter configured to transmit to the energy distributor an energy status message; and a receiver configured to extract energy from a wireless signal received by the wireless communication device from an energy provider and to use the energy extracted from the wireless signal to recharge the rechargeable energy storage, wherein the wireless signal is provided by the energy provider in response to the energy status message transmitted to the energy distributor.
Thus, an improved wireless communication device allowing for RF energy harvesting is provided.
In a first possible implementation form of the first aspect of the invention as such the wireless communication device further comprises a predictor configured to predict the amount of energy required to maintain operation of the wireless communication device until the end of an upcoming time window based on the current level of the rechargeable energy storage and an energy consumption profile of the wireless communication device.
In a second possible implementation form of the first aspect of the invention as such or the first implementation form thereof the energy status message comprises information about the amount of energy required to maintain operation of the wireless communication device until the end of the upcoming time window and/or information about a time interval defining by when the amount of energy required to maintain operation of the wireless communication device has to be received by the wireless communication device.
In a third possible implementation form of the first or second implementation form of the first aspect of the invention the wireless communication device further comprises a profiler configured to generate the energy consumption profile of the wireless communication device.
In a fourth possible implementation form of the third implementation form of the first aspect of the invention the wireless communication device is configured to perform a plurality of processes and the profiler is configured to generate the energy consumption profile of the wireless communication device on the basis of the frequency, the duration and/or the time correlation of the processes of the plurality of processes performed by the wireless communication device within an elapsed time window.
In a fifth possible implementation form of the first to fourth implementation form of the first aspect of the invention the wireless communication device is configured to perform a plurality of processes, wherein the wireless communication device further comprises a scheduler for scheduling processes of the plurality of processes in the upcoming time window, wherein the predictor is configured to predict the amount of energy required to maintain operation of the wireless communication device until the end of the upcoming time window based on the current level of the rechargeable energy storage, the energy consumption profile of the wireless communication device and the scheduled processes in the upcoming time window.
In a sixth possible implementation form of any one of the first to fifth implementation form of the first aspect of the invention the predictor is further configured to predict the end of the upcoming time window on the basis of at least one recharging event within an elapsed time window. In other words, the predictor is configured to take into account past recharging events in order to estimate whether such a recharging is likely to happen before the end of the upcoming time window.
In a seventh possible implementation form of the first aspect of the invention as such or any one of the first to sixth implementation form thereof the transmitter is configured to transmit the energy status message as part of a data message to the energy distributor, i.e. as part of a message containing control data and/or payload data to be provided to the energy distributor.
In an eighth possible implementation form of the first aspect of the invention as such or any one of the first to seventh implementation form thereof the wireless communication device is further configured to perform an energy consuming process involving a further wireless communication device in return for energy provided by the energy provider.
In a ninth possible implementation form of the first aspect of the invention as such or any one of the first to eighth implementation form thereof the energy status message comprises information about the current level of the rechargeable energy storage of the wireless communication device, the level of the rechargeable energy storage of the wireless communication device at the end of an upcoming time window, the storage capacity of the rechargeable energy storage of the wireless communication device and/or a minimum storage level of the rechargeable energy storage required to operate the wireless communication device.
According to a second aspect the invention relates to an energy distributor, in particular a base station or a wireless communication device, configured to communicate with a further wireless communication device, the energy distributor comprising a receiver configured to receive from the further wireless communication device an energy status message, wherein the energy distributor is further configured to cause an energy provider to provide energy to the further wireless communication device by means of a wireless signal in response to the energy status message.
In a first possible implementation form of the second aspect of the invention as such the energy status message comprises information about the current level of a rechargeable energy storage of the further wireless communication device, wherein the energy distributor further comprises a predictor configured to predict the amount of energy required to maintain operation of the further wireless communication device until the end of an upcoming time window based on the current level of the rechargeable energy storage and an energy consumption profile of the further wireless communication device.
In a second possible implementation form of the second aspect of the invention as such or the first implementation form thereof the energy provider is a transmitter of the energy distributor, wherein the transmitter of the energy distributor is configured to provide energy to the further wireless communication device by means of a wireless signal.
According to a third aspect the invention relates to a method of operating a wireless communication device configured to communicate with an energy distributor, in particular a base station or a further wireless communication device, comprising the steps of supplying the wireless communication device with energy from a rechargeable energy storage of the wireless communication device to maintain operation of the wireless communication device, transmitting to the energy distributor an energy status message, and extracting energy from a wireless signal received by the wireless communication device from an energy provider and using the energy extracted from the wireless signal to recharge the rechargeable energy storage, wherein the wireless signal is provided by the energy provider in response to the energy status message transmitted to the energy distributor.
The method according to the third aspect of the invention can be performed by the wireless communication device according to the first aspect of the invention. Further features of the method according to the third aspect of the invention result directly from the functionality of the wireless communication device according to the first aspect of the invention and its different implementation forms described above.
According to a fourth aspect the invention relates to a computer program comprising program code for performing the method according to the third aspect of the invention when executed on a computer.
The invention can be implemented in hardware and/or software.
Further embodiments of the invention will be described with respect to the following figures, in which:
In the following detailed description, reference is made to the accompanying drawings, which form a part of the disclosure, and in which are shown, by way of illustration, specific aspects in which the disclosure may be practiced. It is understood that other aspects may be utilized and structural or logical changes may be made without departing from the scope of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present disclosure is defined by the appended claims.
It is understood that a disclosure in connection with a described method may also hold true for a corresponding device or system configured to perform the method and vice versa. For example, if a specific method step is described, a corresponding device may include a unit to perform the described method step, even if such unit is not explicitly described or illustrated in the figures. Further, it is understood that the features of the various exemplary aspects described herein may be combined with each other, unless specifically noted otherwise.
The wireless communication device 101a-c comprises a rechargeable energy storage 201 in form of a battery configured to supply the wireless communication device 101a-c with energy to maintain operation of the wireless communication device 101a-c. Moreover, the wireless communication device 101a-c comprises a transmitter 203a configured to transmit an energy status message to the energy distributor in form of the base station 103 and a receiver 203b configured to extract energy from a wireless signal received by the wireless communication device 101a-c from an energy provider and to use the energy extracted from the wireless signal to recharge the rechargeable energy storage 201, wherein the wireless signal is provided by the energy provider in response to the energy status message transmitted to the energy distributor in form of the base station 103.
As indicated in
In an embodiment, the energy provider is the base station 103 itself. In such an embodiment the base station 103 can comprise a transmitter configured to provide energy to the wireless communication device 101a-c by means of a wireless signal. Alternatively or additionally, an energy provider can be implemented in form of a dedicated unit in communication with the base station 103 and comprising a transmitter configured to provide energy to the wireless communication device 101a-c by means of a wireless signal.
In an embodiment, the wireless communication device 101a-c further comprises a predictor 205 configured to predict the amount of energy required to maintain operation of the wireless communication device 101a-c until the end of an upcoming time window based on the current level of the rechargeable energy storage 201 and an energy consumption profile of the wireless communication device 101a-c. In an embodiment, the predictor 205 is further configured to predict the end of the upcoming time window on the basis of at least one recharging event of the wireless communication device 101a-c within an elapsed time window.
In an embodiment, the energy status message comprises information about the amount of energy required to maintain operation of the wireless communication device 101a-c until the end of the upcoming time window and/or information about a time interval defining by when the amount of energy required to maintain operation of the wireless communication device 101a-c has to be received by the wireless communication device 101a-c. In an embodiment, the energy status message further comprises information about the current level of the rechargeable energy storage of the wireless communication device, the level of the rechargeable energy storage 201 of the wireless communication device 101a-c at the end of an upcoming time window, the storage capacity of the rechargeable energy storage 201 of the wireless communication device 101a-c and/or a minimum storage level of the rechargeable energy storage 201 required to operate the wireless communication device 101a-c.
In an embodiment, the transmitter 203a of the wireless communication device 101a-c is configured to transmit the energy status message as part of a data message to the energy distributor 103, i.e. as part of a message containing control data and/or payload data to be provided to the energy distributor 103. Alternatively, the energy status message can be a dedicated message.
In an embodiment, the wireless communication device 101a-c further comprises a profiler 207 configured to generate the energy consumption profile of the wireless communication device 101a-c. In an embodiment, the wireless communication device 101a-c is configured to perform a plurality of processes and the profiler 207 is configured to generate the energy consumption profile of the wireless communication device 101a-c on the basis of the frequency, the duration and/or the time correlation of any processes of the plurality of processes performed by the wireless communication device 101a-c within an elapsed time window.
In an embodiment the wireless communication device 101a-c is configured to perform a plurality of processes, wherein the wireless communication device 101a-c further comprises a scheduler 209 for scheduling these processes within the upcoming time window, wherein the predictor 205 is configured to predict the amount of energy required to maintain operation of the wireless communication device 101a-c until the end of the upcoming time window based on the current level of the rechargeable energy storage 201, the energy consumption profile of the wireless communication device 101a-c and the processes scheduled by the scheduler 209 in the upcoming time window.
In an embodiment, the wireless communication device 101a-c is further configured to request and obtain energy in the context of an incentive scheme. For instance, the wireless communication device 101a-c could be configured to perform an energy consuming process that involves a further wireless communication device 101a-c, such as sharing a file with a further wireless communication device, in return for energy provided by the energy provider.
As described above, in an embodiment the predictor 205 configured to predict the amount of energy required to maintain operation of the wireless communication device 101a-c until the end of an upcoming time window based on the current level of the rechargeable energy storage 201 and an energy consumption profile of the wireless communication device 101a-c is part of the wireless communication device 101a-c. Alternatively or additionally, the predictor configured to predict the amount of energy required to maintain operation of the wireless communication device 101a-c until the end of the upcoming time window based on the current level of the rechargeable energy storage 201 and the energy consumption profile of the wireless communication device 101a-c can be implemented as part of the energy distributor, in particular the base station 103.
In a step 301 the wireless communication device 101a-c is continuously supplied with energy from the rechargeable energy storage 201 of the wireless communication device 101a-c to maintain operation of the wireless communication device 101a-c.
In a step 303 an energy status message is transmitted to the energy distributor, in particular the base station 103.
In a step 305 energy is extracted from a wireless signal received by the wireless communication device 101a-c from the energy provider and the energy extracted from the wireless signal is used to recharge the rechargeable energy storage 201 of the wireless communication device 101a-c, wherein the wireless signal is provided by the energy provider in response to the energy status message transmitted to the energy distributor, in particular the base station 103.
In the following, further implementation forms, embodiments and aspects of the wireless communication device 101a-c, the base station 103 and the method 300 are described.
More specifically, in a step 401 the wireless communication device 101a-c obtains information about the current level of its rechargeable battery 201. In steps 403 and 405 the predictor 205 predicts the amount of energy required to maintain operation of the wireless communication device 101a-c until the end of an upcoming time window T based on the current level of the rechargeable battery 201 and checks whether the current level of the rechargeable battery 201 is sufficient. If this is not the case, the wireless communication device 101a-c sends in step 407 of
In a step 501 of
In a step 701 the predictor 205 predicts the amount of energy required to maintain operation of the wireless communication device 101a-c until the end of an upcoming time window based on the current level of the rechargeable battery 201 and checks whether the current level of the rechargeable battery 201 is sufficient. In a step 703 the wireless communication device 101 sends an energy status message to the base station 103 in order to request from the base station energy to be provided by the energy provider. As already described above, the energy status message could include information, such as the current battery status comprising state-of-charge (SoC) of the battery 201 as well as the storage capacity of the battery 201, minimum charge level necessary for the wireless communication device 101a-c to operate, the requested energy to harvest, corresponding timeline and the like. In an embodiment, the energy level information could be provided using a quantized state that corresponds to potential categories (e.g. window of energy demand and a three level timeline, such as “vital”, “urgent” and “normal”). Such a quantification allows to decrease the number of bits necessary for the transmission of this information. In an embodiment, the Physical Downlink Control Channel (PDCCH) (as defined in the LTE standard) is used to transport the energy status message.
Once the base station 103 has received the energy status message from the wireless communication device 101a-c, it handles this request in a step 705. As in the embodiment shown in
The devices described herein may be implemented as optical circuit within a chip or an integrated circuit or an application specific integrated circuit (ASIC). The invention can be implemented in digital and/or analogue electronic and optical circuitry.
While a particular feature or aspect of the disclosure may have been disclosed with respect to only one of several implementations or embodiments, such feature or aspect may be combined with one or more other features or aspects of the other implementations or embodiments as may be desired and advantageous for any given or particular application. Furthermore, to the extent that the terms “include”, “have”, “with”, or other variants thereof are used in either the detailed description or the claims, such terms are intended to be inclusive in a manner similar to the term “comprise”. Also, the terms “exemplary”, “for example” and “e.g.” are merely meant as an example, rather than the best or optimal. The terms “coupled” and “connected”, along with derivatives may have been used. It should be understood that these terms may have been used to indicate that two elements cooperate or interact with each other regardless whether they are in direct physical or electrical contact, or they are not in direct contact with each other.
Although specific aspects have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific aspects shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the specific aspects discussed herein.
Although the elements in the following claims are recited in a particular sequence with corresponding labeling, unless the claim recitations otherwise imply a particular sequence for implementing some or all of those elements, those elements are not necessarily intended to be limited to being implemented in that particular sequence.
Many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the above teachings. Of course, those skilled in the art readily recognize that there are numerous applications of the invention beyond those described herein. While the present invention has been described with reference to one or more particular embodiments, those skilled in the art recognize that many changes may be made thereto without departing from the scope of the present invention. It is therefore to be understood that within the scope of the appended claims and their equivalents, the invention may be practiced otherwise than as specifically described herein.
This application is a continuation of International Application No. PCT/EP2015/067663, filed on Jul. 31, 2015, which is hereby incorporated by reference in its entireties.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/EP2015/067663 | Jul 2015 | US |
| Child | 15869462 | US |
