KR102240893B1 - Electromagnetic wave transmitting and receiving system capable of position tracking, identification and wireless power transmission to objects - Google Patents

Abstract

An electromagnetic wave transmission/reception system capable of location tracking, identification, and wireless power transmission for an object according to an embodiment of the present invention transmits a frequency signal to the object, and is based on a phase and frequency change of a backscattered signal of a target portion with respect to the frequency signal. A radio wave transmitting/receiving unit for determining the location and unique information of the target unit may be included, and the target unit may transmit the unique information to the radio wave transmitting/receiving unit through backscattering modulation of a frequency signal transmitted from the radio wave transmitting unit.

Description

Electromagnetic wave transmission/reception system capable of location tracking, identification and wireless power transmission for an object {ELECTROMAGNETIC WAVE TRANSMITTING AND RECEIVING SYSTEM CAPABLE OF POSITION TRACKING, IDENTIFICATION AND WIRELESS POWER TRANSMISSION TO OBJECTS}

The present invention relates to an electromagnetic wave transmission/reception system capable of location tracking, identification, and wireless power transmission for an object, and more particularly, tracking the distance and location to a remote object (ie, a passive receiving end) and acquiring unique information at the same time. Thus, the present invention relates to an electromagnetic wave transmission/reception system capable of transmitting wireless power through a beamforming technique while identifying a target portion even in an environment of less than spatial resolution.

Conventional electromagnetic wave systems that provide a single application service by transmitting a signal or power from a fixed base station to an object identify the location (or classification) of the object, and identify the object that wants to provide the application service (ie, check the unique information of the object). However, there are technical limitations in terms of the use of power energy for realization of application services. It can be seen that this is because all of the conventional electromagnetic wave systems are based on electromagnetic wave transmission technology, but technology development is being made according to the characteristics of each unique application field.

For example, a radar system, which is one of the conventional electromagnetic wave systems, has a technical limitation in not properly distinguishing the positions of a plurality of objects in an environment with a distance and a position resolution or less. The radar identifies an object by measuring a radar cross section (RCS) based on an object's own reflection signal, which is based on the shape of the object and does not confirm the unique information. In particular, the most problematic occurs when a plurality of different objects having similar radar cross-sectional characteristics are separated again after being located within the distance and position resolution. At this time, since it is difficult for the radar to clearly grasp the moving paths of the objects, tracking of the object is practically meaningless. This problem can become a bigger problem in radar sensor technology that needs to acquire information for a variety of subjects.

In addition, a wireless power transmission system, which is one of the conventional electromagnetic wave systems, has to consume battery power in the receiver in order to determine the location of the receiver, which is an object, and there is a technical limitation that requires a dual-band frequency and an antenna. In order to transmit power to a remotely located receiver, the location of the receiver must be identified prior to wireless power transmission, but conventionally, a retro-directive method of detecting the position by detecting the isotropic pilot signal radiated from the receiver is used. Was used. However, since this consumes a considerable amount of power to radiate the pilot signal, it can paradoxically lower the power use efficiency of a receiver receiving wireless power. In addition, since a battery configuration or the like for generating a pilot radiation signal is required in the receiver, the structure of the receiver itself is inevitably complicated.

Another conventional RFID system, one of the electromagnetic wave systems, is largely divided into a passive RFID system and an active RIFD system. In the case of a passive RFID system, it is possible to check the unique information of the tag, which is an object, and it can be operated without a battery in the tag, but it is difficult to grasp the position of the tag (ie, the distance and direction angle between the reader station and the tag). Difficult technical limitations exist. In the case of an active RFID system, since a pilot signal is radiated using a battery mounted inside the tag, the power use efficiency decreases as in the conventional wireless power transmission system, thus limiting the application and reducing the size and price of the tag. There is a problem that cannot but increase.

That is, conventional electromagnetic wave systems such as the radar system, wireless power transmission system, and RFID system described above have distinct advantages and disadvantages in terms of energy efficiency for distinguishing and distinguishing objects. The strengths and weaknesses of these clearly distinguished systems are factors that make it difficult to develop and provide a new service that combines several application fields required in the recent market. Therefore, it is indispensable to develop a new electromagnetic wave transmission/reception system incorporating the advantages and solving the disadvantages of each electromagnetic wave system.

Republic of Korea Patent Publication No. 10-2015-0137885 (2015.12.09)

The present invention was conceived in accordance with the necessity of developing a new electromagnetic wave transmission/reception system as described above, and it is possible to locate and identify a distant object even in an environment less than spatial resolution by using a liquid crystal-based receiving end that does not require power consumption. , An object of the present invention is to provide an integrated electromagnetic wave transmission/reception system capable of efficient wireless power transmission for an identified object.

An electromagnetic wave transmission/reception system capable of location tracking, identification, and wireless power transmission for an object according to an embodiment of the present invention transmits a frequency signal to the object, and is based on a phase and frequency change of a backscattered signal of a target portion with respect to the frequency signal. A radio wave transmitting/receiving unit for determining the location and unique information of the target unit may be included, and the target unit may transmit the unique information to the radio wave transmitting/receiving unit through backscattering modulation of a frequency signal transmitted from the radio wave transmitting unit.

The radio wave transmitting/receiving unit according to an embodiment of the present invention may determine a phase change of a backscatter signal received from the target unit based on the frequency signal, and estimate a position of the target unit from the phase change of the backscatter signal.

The radio wave transmitting/receiving unit according to an embodiment of the present invention may determine a change in a resonant frequency of a backscattered signal received from the target part based on the frequency signal, and extract the unique information of the target part from the change in the resonant frequency of the backscatter signal. .

The radio wave transmitting/receiving unit according to an embodiment of the present invention may transmit an electromagnetic wave for beamforming-based wireless power transmission to a target portion for which unique information is identified.

The radio transmission/reception unit according to an exemplary embodiment of the present invention may include a plurality of array antennas for distinguishing an object and a target unit disposed at the same position from the radio transmission/reception unit.

The target unit according to an exemplary embodiment of the present invention may be configured of a substrate or a transmission line including a liquid crystal, and may control a bias voltage for a liquid crystal having a variable dielectric constant to generate a backscatter signal including unique information.

In the electromagnetic wave transmitting/receiving system according to an embodiment of the present invention, the dielectric constant of the liquid crystal and the resonant frequency of the backscattered signal change according to the magnitude of the bias voltage controlled by the target portion, so that unique information for identifying the target portion may be different. .

The radio wave transmitting/receiving unit according to an embodiment of the present invention may include a display for visually outputting the location and unique information of the target unit.

Through the electromagnetic wave transmission/reception system provided as an embodiment of the present invention, the following remarkable effects can be achieved compared to the existing technology.

(1) Since it is possible to implement a communication connection with an object within a single frequency bandwidth, it is possible to increase the efficiency of using the frequency bandwidth. In addition, the improvement in transmission (or reception) efficiency within a single frequency bandwidth is directly linked to the improvement in service provision efficiency, and thus the improvement effect at the system level can be increased by improving device and circuit technology.

(2) Like a wireless power transmission service, the present invention enables practical operation of a service that requires data transmission and reception while using a frequency band for transmitting high power within an adjacent frequency. In addition, it is possible to propose a base technology of an electromagnetic wave location and ID recognition sensor that does not require power consumption of an object while overcoming the spatial characteristic constraints and details of the existing location recognition system in terms of research and technology.

(3) In terms of industry and economy, it is possible to improve the efficiency of the wireless power transmission system through receiver identification as well as recognition of the location of multiple objects. For example, the present invention can be used in personalized wearable healthcare products and services in which health information of individuals in various locations is obtained in real time and the usage time is greatly increased through wireless charging. In addition, the present invention monitors the use of space according to the floating population in the living environment of private houses, apartments and buildings, and controls the use of lighting, opening doors, elevators, etc. related to increase energy and space utilization and can be easily managed. It can be used for smart building services. In addition, the present invention can establish a management system that checks the real-time location of a passive object within a specific area in the existing RFID market, thereby enabling automated management along with location confirmation/tracking in a logistics environment with low cost and high efficiency.

1 is a conceptual diagram illustrating an electromagnetic wave transmission/reception system according to an embodiment of the present invention.
2 is a conceptual diagram showing a state of identifying the location and unique information of the target portion of the radio wave transmission and reception unit according to an embodiment of the present invention.
3 is a conceptual diagram showing a state in which wireless power is transmitted to a target unit for which unique information of a radio wave transmitting/receiving unit is identified according to an embodiment of the present invention.
4 is a conceptual diagram illustrating a principle of determining a location of an object of a radio wave transmitting/receiving unit according to an embodiment of the present invention.
FIG. 5 is a conceptual diagram illustrating the entire operation of location tracking, identification of unique information, and wireless power transmission of an electromagnetic wave transmission/reception system according to an embodiment of the present invention.
6 is a conceptual diagram illustrating a detailed configuration and function of a target unit according to an embodiment of the present invention.
7 is a conceptual diagram showing the operating principle of an electromagnetic wave transmission/reception system for simultaneously checking a distance and unique information of a target portion using a transmission signal according to an embodiment of the present invention.

The terms used in the present specification will be briefly described, and the present invention will be described in detail.

Terms used in the present invention have selected general terms that are currently widely used as possible while taking functions of the present invention into consideration, but this may vary according to the intention or precedent of a technician working in the field, the emergence of new technologies, and the like. In addition, in certain cases, there are terms arbitrarily selected by the applicant, and in this case, the meaning of the terms will be described in detail in the description of the corresponding invention. Therefore, the terms used in the present invention should be defined based on the meaning of the term and the overall contents of the present invention, not a simple name of the term.

When a part of the specification is said to "include" a certain component, it means that other components may be further included rather than excluding other components unless specifically stated to the contrary. In addition, terms such as "... unit" and "unit" described in the specification mean a unit that processes at least one function or operation, which may be implemented as hardware or software or a combination of hardware and software. .

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and similar reference numerals are attached to similar parts throughout the specification.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a conceptual diagram illustrating an electromagnetic wave transmission/reception system according to an embodiment of the present invention.

Conventional radar, RFID, and electromagnetic wave transmission/reception systems such as wireless power transmission systems are being developed in accordance with the characteristics of each unique application field. For this reason, each of the conventional electromagnetic wave transmission/reception systems has technical limitations. For example, in the case of radar, since a method of measuring a radar cross section (RCS) by a reflected signal is used, the position of a plurality of objects is distinguished and the movement path is clearly defined in an environment less than the distance and position resolution. There is a problem that is difficult to grasp.

Passive RFID does not have a battery, so it is difficult to obtain the location information of a tag, and active RFID and wireless power transmission systems have a problem in that a battery must be embedded because a pilot signal must be radiated. In addition, since considerable power is consumed to emit a pilot signal, there is a problem in that power use efficiency is deteriorated and the structure of a tag or a receiver is complicated.

The electromagnetic wave transmission/reception system according to an embodiment of the present invention refers to an integrated wireless communication system capable of overcoming the technical limitations of the conventional radar, RFID, and wireless power transmission systems described above. That is, the electromagnetic wave transmission/reception system according to an embodiment of the present invention can determine the location of an object from a detection signal reflected from a distant object without a separate communication channel, identify unique information, and identify the unique information to the identified object. For beamforming-based wireless power transmission may be possible.

For example, referring to FIG. 1, a radio wave transmitting/receiving unit 100 for generating an electromagnetic wave according to an exemplary embodiment of the present invention includes a target unit 200 and an uninterested object 300 to provide an electromagnetic wave signal. Can be sent out. The radio wave transmitting/receiving unit 100 may receive a backscatter signal from a target unit 200 that generates a backscatter signal including unique information among a plurality of objects without a battery. The radio wave transmitting/receiving unit 100 simultaneously grasps the location and unique information (ex. ID, etc.) of the target unit 200 from the backscattered signal, and targets wireless power using beamforming based on the identified position and unique information. It can be transmitted to the unit 200.

2 is a conceptual diagram showing a state of identifying the location and unique information of the target unit 200 of the radio wave transmitting and receiving unit 100 according to an embodiment of the present invention.

The radio wave transceiving unit 100 according to an embodiment of the present invention may transmit a frequency signal to an object and receive a backscatter signal from the target unit 200 (or the uninterested object 300) for the frequency signal. . In this case, the radio wave transmitting/receiving unit 100 may determine the location and unique information of the target unit 200 (or the uninterested object 300) based on the phase and frequency change of the backscattered signal with respect to the frequency signal.

For example, referring to FIG. 2, the radio wave transmitting/receiving unit 100 may transmit a frequency signal toward a plurality of objects. Among the plurality of objects, an object A 210, which is a target unit 200, receives a frequency signal. While the backscattered modulated reflected signal may be transmitted to the radio wave transmitting/receiving unit 100. The radio wave transmitting/receiving unit 100 may receive a reflected signal that has been backscattered and modulated by the object A 210, and based on this, may determine the location of the object A 210 and identify unique information.

The radio wave transmitting/receiving unit 100 according to an embodiment of the present invention determines a phase change of a backscatter signal received from the target unit 200 (or an uninterested object 300) based on the frequency signal, and The position of the target unit 200 (or the uninterested object 300) may be estimated from the phase change of. That is, the radio wave transmitting/receiving unit 100 may estimate the location of the object that has transmitted the reflected signal based on the time when the reflected signal for the frequency signal arrives.

For example, referring to FIG. 2, the radio wave transmitting/receiving unit 100 may receive a reflected signal that has been backscattered and modulated by the target A 210, which is the target unit 200. At this time, since the time for the reflected signal to reach the radio wave transmitting and receiving unit 100 varies according to the distance of the object A 210, the radio wave transmitting and receiving unit 100 adjusts the phase change of the reflected signal backscattered with respect to the frequency signal. After grasping, it is possible to estimate the location of the object A 210 based on this.

The radio wave transmitting/receiving unit 100 according to an embodiment of the present invention determines a change in the resonant frequency of the backscattered signal received from the target unit 200 based on the frequency signal, and based on the change in the resonant frequency of the backscatter signal, the target unit ( 200) can be extracted. That is, the radio wave transmitting/receiving unit 100 analyzes the position change of the resonant frequency of the reflected signal with respect to the frequency signal, and determines the unique information of the object transmitting the reflected signal based on the pattern of the reflected signal identified as a result of this analysis. I can.

For example, referring to FIG. 2, the radio wave transmitting/receiving unit 100 may receive a reflected signal that has been backscattered and modulated by the target A 210, which is the target unit 200. In this case, the object A 210 may perform backscatter modulation by changing the resonant frequency of the antenna or circuit through the change of the dielectric constant of the liquid crystal through voltage control, and encode the unique information. The radio wave transmitting/receiving unit 100 may grasp a change in the resonant frequency of the reflected signal that has been backscattered with respect to the frequency signal, and extract unique information of the object A 210 based on this.

Meanwhile, referring to FIG. 2, the radio wave transmitting/receiving unit 100 according to an embodiment of the present invention may include a display 140 for visually outputting the location and unique information of the target unit 200. That is, when the location and unique information of the target unit 200 (or the uninterested object 300) is determined through the above-described process, the radio wave transmitting/receiving unit 100 transmits the location and the unique information of the target unit 200 to text and It may be converted into output data such as an image and output through the display 140.

For example, when the location and unique information of the object A 210 is determined based on the reflected signal backscattered and modulated by the target unit 200, the object A 210, the radio wave transmitting/receiving unit 100 The position of 210) may be converted into a radar image and may be output through the display 140. In addition, the radio wave transmission/reception unit 100 may convert an ID (i.e. unique information for identification) and a location of the object A 210 into text data and output it through the display 140. In this case, as shown in FIG. 2, the location of the object A 210 may be expressed as coordinate values of X, Y, and Z, but is not limited thereto.

3 is a conceptual diagram showing a state in which wireless power is transmitted to a target unit 200 in which the unique information of the radio wave transmitting/receiving unit 100 is identified according to an embodiment of the present invention.

The radio wave transmitting/receiving unit 100 according to an embodiment of the present invention may transmit an electromagnetic wave for beamforming-based wireless power transmission to the target unit 200 whose unique information is identified. That is, the radio wave transmitting/receiving unit 100 may transmit the wireless power by focusing only on the target unit 200 whose unique information is identified among a plurality of objects and transmitting the electromagnetic wave. Using the wireless power transmitted based on beamforming, the target unit 200 may perform an additional operation such as data sensing without a battery.

For example, referring to FIG. 3, the radio wave transmitting/receiving unit 100 determines the positions of the object A 210 and the object B 310 through the backscatter signals received from the object A 210 and the object B 310. I can grasp it. In this case, the object A 210, which is the target unit 200, may include intrinsic information such as “Device A” in the backscatter signal, unlike the object B 310, which is the uninterested object 300, so that the radio wave transmission/reception unit ( 100) may identify the unique information of the object A 210 and distinguish between the object A 210 and the object B 310. When the distinction between the object A 210 and the object B 310 and identification of the unique information on the object A 210 is completed, the radio transmission/reception unit 100 receives wireless power for only the object A 210 whose unique information is identified. It is possible to transmit an electromagnetic wave signal based on beamforming for transmission.

Referring to FIG. 3, in the case of an object capable of generally backscattering modulation (ex. a conventional RFID tag, etc.), such as the object B 310, the radio wave transmitting/receiving unit 100 can grasp unique information for distinguishing the corresponding object. It can't be, but the location can be determined. Accordingly, the location of the object B 310 may be displayed even if the unique information of the object B 310 is not displayed on the display 140 of the radio wave transmitting/receiving unit 100.

4 is a conceptual diagram showing a principle of determining the position of an object of the radio wave transmitting/receiving unit 100 according to an embodiment of the present invention. FIG. 5 is a location tracking and unique information of an electromagnetic wave transmitting/receiving system according to an embodiment of the present invention. This is a conceptual diagram of the entire operation of identification and wireless power transmission.

Unlike the non-interested object 300 capable of backscattering modulation, the target unit 200 according to an embodiment of the present invention may transmit unique information through a method such as controlling a change in dielectric constant of a liquid crystal. That is, both the target unit 200 and the uninterested object 300 can transmit the reflected signal through backscattering modulation for the frequency signal transmitted from the radio wave transmitting/receiving unit 100, but the target unit 200 is uninterested. Unique information for distinguishing from the object 300 may be included in the reflected signal and transmitted.

Referring to FIG. 4A, when present at different positions from the target part 200 and the non-interested object 300, backscatter signals received from the target part 200 and the non-interested object 300, respectively Since the spectrum of is completely distinguished, the radio wave transmitting/receiving unit 100 can accurately identify the target unit 200 and the uninterested object 300 by distinguishing the backscattered signal. On the other hand, referring to FIG. 4B, when present at the same position as the target part 200 and the non-interested object 300, the backscatter received from the target part 200 and the non-interested object 300, respectively. Since the spectrum of the signal collides, there may be a problem in that the radio wave transmission/reception unit 100 cannot distinguish between the backscattered signals received from the target unit 200 and the uninterested object 300, respectively.

In order to solve the spectrum collision problem as shown in (b) of FIG. 4, the radio wave transmitting/receiving unit 100 according to an embodiment of the present invention distinguishes between an object disposed at the same position from the radio wave transmitting and receiving unit 100 and the target unit 200. It may include a plurality of array antennas 110 for. That is, the radio wave transmitting/receiving unit 100 variously configures the distance from the radio wave transceiver to the object through the array-type antenna 110 having a predetermined interval or pattern, so that spectral collisions between backscattered signals received from a plurality of objects Can be minimized.

For example, referring to FIG. 5, a plurality of array antennas 110 may be classified into a transmission antenna and a reception antenna. In this case, in the case of the receiving antenna, it may be configured and disposed in a larger number than the transmitting antenna, and may be configured to have a predetermined interval or pattern in order to minimize collision of a reflected signal received from an object.

Referring to FIG. 5, a plurality of array antennas 110 may be connected to a first processor 120 constituting a transmission/reception channel. Based on the backscattering signal collected by the first processor 120, the second processor 130 may distinguish between the target unit #1 220 having an ID and the object 320 without an ID, and track the position of the object. have. The location and unique information of the target unit #1 220 identified by the second processor 130 may be output through the display 140. Meanwhile, the second processor 130 may form a beam for wireless power transmission to the target unit #1 220 whose location and unique information are identified, and select a beamforming mode for transmitting the beam. According to the beamforming mode selected by the second processor 130, the electromagnetic wave signal may be transmitted to the target unit #1 220 whose location and unique information are identified.

6 is a conceptual diagram showing a detailed configuration and function of the target unit 200 according to an embodiment of the present invention.

The target part 200 according to an embodiment of the present invention includes a target part antenna 10 for receiving a frequency signal, and a permittivity to generate a backscatter signal including unique information for identifying the target part 200. Including a backscatter modulator 20 for controlling the bias voltage for the variable liquid crystal and a wireless power management unit 30 for controlling the amount of power transmitted from the signal received by the target antenna 10 and the magnitude of the backscatter signal. can do.

The target antenna 10 according to an embodiment of the present invention may receive a signal of a single frequency bandwidth transmitted from the radio wave transmitting/receiving unit 100. At this time, the signal of a single frequency bandwidth is based on a frequency signal transmitted to check the position and unique information of the target unit 200 or a beamforming unit transmitted for power transmission to the target unit 200 whose position and unique information are identified. Say the signal. That is, the target unit 200 according to an embodiment of the present invention not only performs backscattering modulation so that the radio wave transceiving unit 100 can identify the location and unique information, but also transmits the radio wave transceiving unit 100 without a battery. An antenna 10 may be provided to operate by receiving wireless power of a signal.

The backscatter modulator 20 according to an embodiment of the present invention may include unique information for identifying the target part 200 in the backscatter signal. That is, the backscatter modulator 20 may generate unique information for each target unit 200 by controlling the bias voltage of the liquid crystal without a separate battery or oscillator. In this case, in order to generate the unique information of the backscatter modulator 20, the target unit 200 may be manufactured with at least one of a substrate composed of a liquid crystal or a transmission line including a liquid crystal.

For example, the backscatter modulator 20 may control a bias voltage for a liquid crystal constituting a substrate or a transmission line of the target unit 200. The backscatter modulator 20 may determine and generate unique information for distinguishing the target part 200 from the non-interested object 300 by changing the dielectric constant of the liquid crystal through the control of the bias voltage. The backscatter modulator 20 may perform backscatter modulation so that the unique information generated through the above-described process is included in the backscatter signal so that the unique information of the target unit 200 can be recognized.

6, the backscatter modulator 20 according to an embodiment of the present invention modulates the backscatter signal by varying the impedance of the antenna 10 or the load impedance of the rectifier 31 over time. I can. That is, the backscatter modulator 20 not only generates unique information for object identification by controlling the bias voltage, but also unique information generated by controlling the impedance of the antenna 10 or the load impedance of the rectifier 31 over time. May be transmitted to the radio wave transmitting/receiving unit 100 through the backscattered modulated reflected signal.

The wireless power management unit 30 according to an embodiment of the present invention is configured to transmit the radio power included in the frequency signal or the beamforming-based signal received by the target unit 200 for which unique information is identified. It can be used as a power source for operation. For example, the wireless power management unit 30 transfers the wireless power of the signal received through the target antenna 10 to the backscatter modulator 20, and the backscatter modulator 20 transfers the received wireless power. It can be used for the generation of unique information and backscattering modulation. In this case, the wireless power management unit 30 may control the amount of power transmitted from the signal received by the antenna 10 by controlling the impedance of the load of the rectifier 31. In addition, the wireless power management unit 30 may control the magnitude of the backscattering signal by controlling the amount of power.

Referring to FIG. 6, the wireless power management unit 30 according to an embodiment of the present invention may track changes in the load impedance of the rectifier 31 in real time to control the amount of power. Since the amount of power of the signal received from the antenna 10 is affected by the load of the rectifier 31, the rectifier 31 variable by the wireless power management unit 30 itself or the backscatter modulator 20 for maximum power collection. It is necessary to monitor the load impedance of) in real time. For such monitoring, the wireless power management unit 30 can control the load impedance of the rectifier 31 as well as track changes in the load impedance in real time.

For example, the power management circuit 32 of the wireless power management unit 30 may modulate the load of the rectifier 31. In this case, the power management circuit 32 may perform feedback sensing to track and check the load impedance value of the rectifier 31 in real time in order to collect the maximum amount of power from the signal received from the target antenna 10. The power collected through the power management circuit 32 can be transferred to a DC load 40 such as an IoT sensor core, and the DC load 40 uses the received power to meet the purpose of use of the target unit 200. Data sensing can be performed.

7 is a conceptual diagram showing the operating principle of an electromagnetic wave transmission/reception system that simultaneously checks the distance and unique information of the target unit 200 using a transmission signal according to an embodiment of the present invention.

The targeting unit 200 according to an embodiment of the present invention is the resonant frequency of the backscattered signal for the frequency signal so that the radio wave transmitting and receiving unit 100 can grasp the unique information that distinguishes an object that is not an object to be identified in the electromagnetic wave transmission/reception system. It is characterized by generating a change. In order to change the resonant frequency of the backscattered signal (ie, modulation of the backscattered signal), a method of changing the dielectric constant of a liquid crystal or a method of changing the resonance structure of the target part antenna 10 may be used for the target part 200. .

The method of changing the dielectric constant of the liquid crystal refers to a method of backscattering the peculiar information (i.e. unique ID) of the target portion 200 using the dielectric constant characteristic of the liquid crystal that is varied according to the bias voltage. For example, if the bias voltage applied to the liquid crystal is set differently for each target part 200, the resonant frequency of the antenna 10 or matching circuit composed of a substrate or transmission line including the liquid crystal is different for each target part 200. You lose. Accordingly, since the resonant frequency of the backscattered signal is also different for each target unit 200, in the electromagnetic wave transmission/reception system, the target unit 200 can be distinguished based on the position of the resonant frequency of the backscattered signal.

As described above, the backscatter modulator 20 according to an embodiment of the present invention may control the magnitude of the bias voltage applied to the liquid crystal constituting the target unit 200. Since the magnitude of the bias voltage varied by the backscatter modulator 20 affects the change in the dielectric constant of the liquid crystal and the resonant frequency of the backscatter signal, the backscatter modulator 20 controls the size of the bias voltage to It is possible to change the dielectric constant and the resonant frequency of the backscattering signal accordingly, and determine the unique information for identification of the object.

For example, referring to FIG. 7, the Rx 1 230, which is a target portion using the dielectric constant characteristic of the liquid crystal, may perform backscatter modulation on a frequency signal received from the radio wave transmitting/receiving unit 100. At this time, the backscatter modulator 20 of the Rx 1 230 changes the dielectric constant of the liquid crystal by applying a preset bias voltage to the liquid crystal, and through this, the backscatter modulation by changing the resonance frequency of the antenna 10 or the matching circuit. You can do it. A change in the resonant frequency of the backscattered signal modulated through this process represents the intrinsic information of the Rx 1 230 for distinguishing it from the uninterested object 300.

In addition to the method of controlling the size of the bias voltage of the backscatter modulator 20 according to an embodiment of the present invention, the resonance of the backscatter signal for a constant bias voltage by different types of liquid crystals constituting the target part 200 It may cause a change in the number of main skins. That is, when the type of liquid crystal itself is different, a difference in reaction speed to the same bias voltage occurs, so the resonant frequency of the backscatter signal is changed by using the difference in reaction speed of the liquid crystal to a predetermined bias voltage, and Unique information can be created.

For example, assuming that there are two target parts composed of different types of liquid crystals, even if the backscatter modulators of each of the two target parts apply the same bias voltage to the liquid crystal, the backscattering signal modulated due to the difference in the reaction speed of the liquid crystal The positions of the resonant frequencies may be different from each other. In other words, since the unique information of each of the two target parts is different according to the reaction speed of the liquid crystal constituting each of the two target parts, in the electromagnetic wave transmission/reception system, the two target parts can be identified based on the unique information.

On the other hand, the method of changing the resonance structure of the target antenna 10 uses a change in the physical structure, size, shape, etc. of the target antenna 10 to obtain the unique information (ie unique ID) of the target part 200. It refers to the method of backscattering. For example, if the size and shape of the target antenna 10 are designed differently for each target portion 200, the resonant frequency of the target antenna 10 varies for each target portion 200. Accordingly, since the resonant frequency of the backscattered signal is also different for each target unit 200, in the electromagnetic wave transmission/reception system, the target unit 200 can be distinguished based on the position of the resonant frequency of the backscattered signal.

That is, even if the bias voltage is not separately controlled in the backscatter modulator 20 according to an embodiment of the present invention, by varying the resonance structure of the target antenna 10, unique information is different for each target unit 200. Can be set. For example, referring to FIG. 7, the Rx 2 240 manufactured with the antenna 10 having a larger size than the Rx 1 230 receives the same frequency signal as the Rx 1 230, but the Rx 1 230 It is possible to generate a backscattered signal having a location of a resonance frequency different from that of.

The above description of the present invention is for illustrative purposes only, and those of ordinary skill in the art to which the present invention pertains will be able to understand that other specific forms can be easily modified without changing the technical spirit or essential features of the present invention will be. Therefore, it should be understood that the embodiments described above are illustrative and non-limiting in all respects. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as being distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the claims to be described later rather than the detailed description, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention. .

10: target antenna 20: backscatter modulator
30: wireless power management unit 31: rectifier
32: power management circuit 40: DC load
100: radio wave transmitting and receiving unit 110: array type antenna
120: first processor 130: second processor
140: display 200: target portion
300: uninterested subject

Claims (8)

In the electromagnetic wave transmission and reception system capable of location tracking, identification and wireless power transmission for an object,
A target unit for controlling a bias voltage through variable dielectric constant to generate a backscattering signal from the object; And
A radio wave transmitting/receiving unit for transmitting a frequency signal to an object and determining a position and unique information of the target unit based on a backscatter signal of the target unit for the frequency signal,
The target portion,
A target antenna for receiving the frequency signal;
A backscatter modulator for controlling a bias voltage through variable dielectric constant for generating a backscatter signal with respect to the frequency signal received from the target antenna; And
Further comprising a wireless power management unit for controlling the impedance of the rectifier load to control the amount of power transmitted from the frequency signal,
Through backscattering modulation of the frequency signal transmitted from the radio wave transmitting and receiving unit, power is used without a battery by utilizing the received energy of the frequency signal, and the dielectric constant and the resonant frequency of the backscattered signal are changed according to the magnitude of the bias voltage. By changing, the electromagnetic wave transmission and reception system, characterized in that generating unique information for identifying the target portion.
The method of claim 1,
The radio wave transmitting and receiving unit,
And determining a phase change of a backscattered signal received from the target part based on the frequency signal, and estimating a position of the target part from the phase change of the backscattered signal.
The method of claim 1,
The radio wave transmitting and receiving unit,
An electromagnetic wave transmission/reception system, characterized in that, based on the frequency signal, the resonant frequency change of the backscattered signal received from the target part is determined, and the unique information of the target part is extracted from the resonant frequency change of the backscattered signal.
The method of claim 1,
The radio wave transmitting and receiving unit,
An electromagnetic wave transmission/reception system, characterized in that for transmitting an electromagnetic wave for beamforming-based wireless power transmission to a target portion for which the unique information is identified.
The method of claim 1,
The radio wave transmitting and receiving unit,
An electromagnetic wave transmission/reception system comprising a plurality of array antennas for distinguishing between the target unit and the object disposed at the same position from the radio wave transmission/reception unit.
The method of claim 1,
The target portion,
An electromagnetic wave transmission/reception system comprising a substrate or a transmission line including a liquid crystal.
The method of claim 6,
The liquid crystal has a variable dielectric constant in order to generate a backscattered signal including intrinsic information,
The target portion,
An electromagnetic wave transmission/reception system comprising controlling a bias voltage through variable dielectric constant of the liquid crystal to generate a backscattered signal from the object.
The method of claim 1,
The radio wave transmitting and receiving unit,
An electromagnetic wave transmission/reception system comprising a display for visually outputting the position and the unique information of the target part.

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