Tracking device, terminal equipment and tracking method

Abstract

The embodiment of the present invention provides a tracking device, a terminal device and a tracking method, which adopts backscattering technology, avoids the complex data exchange standard of Bluetooth, and improves the data extraction efficiency. It includes: a backscattering device; the backscattering device is used to receive a first continuous wave; according to the first continuous wave, a first Bluetooth low-power broadcast signal is reflected, and the first Bluetooth low-power broadcast signal includes the identification of the tracking device.

Description

Technical Field

[0001] The present invention relates to the field of communications, and in particular to a tracking device, a terminal device and a tracking method. Background Art

[0002] When Covid-19 (coronavirus) was rampant around the world in 2020, internationally renowned companies joined the fight against the epidemic, trying to use technology to defeat the epidemic or slow down its spread. Among them, a company launched a contact tracking system for the Covid-19 virus, which relies on Bluetooth Low Energy (BLE) technology to establish a contact tracking system. The tracking system can be applied to Apple (iOS) or Android (android) smart terminals, and through the use of Bluetooth beacons, it can obtain the contact history of people, that is, when and where person A and person B have been in contact, and achieve close-range personnel tracking.

[0003] The above tracking system does not require the purchase of hardware separately, because Bluetooth and Bluetooth BLE technology are widely integrated into smart terminals, and users only need to use existing smart terminals. However, the communication distance of Bluetooth BLE technology is 10-100 meters, which is a large range and is not suitable for short-distance personnel tracking. Moreover, the Bluetooth BLE communication standard is complex, and transmission and reception need to be allocated according to the communication standard, and the underlying software implementation is complex. If the Bluetooth 5.0 standard is followed, a Bluetooth device can connect to up to 7 other devices at the same time, so the number of people tracked using Bluetooth is limited, and if there is a large-scale gathering at the same time, it is not possible to effectively track all participants. Summary of the invention

[0004] The embodiments of the present invention provide a tracking device, a terminal device and a tracking method, which are used to adopt backscatter technology, avoid using complex Bluetooth data exchange standards, and improve data extraction efficiency.

[0005] A first aspect of an embodiment of the present invention provides a tracking device, comprising: a backscattering device; the backscattering device is used to receive a first continuous wave; based on the first continuous wave, a first Bluetooth low-power broadcast signal is reflected, and the first Bluetooth low-power broadcast signal includes an identifier of the tracking device.

[0006] In some embodiments of the present invention, the backscatter device includes: a processor, an oscillator, an encoder and a first Bluetooth antenna, the processor is connected to the oscillator, the oscillator is connected to the encoder, and the encoder is connected to the first Bluetooth antenna;

[0007] The processor is specifically used to receive the first continuous wave through the first Bluetooth antenna; according to the first continuous wave, control the oscillator to switch the target frequency, control the encoder to encode according to the target frequency, and reflect the first Bluetooth low-power broadcast signal through the first Bluetooth antenna.

[0008] In some embodiments of the present invention, the backscatter device further comprises: a rectifier, the rectifier being connected to the processor;

[0009] The rectifier is used to obtain the first continuous wave, convert the first continuous wave into a direct current signal, and start the processor when the voltage of the direct current signal is higher than a preset threshold.

[0010] In some embodiments of the present invention, the tracking device further comprises: a continuous wave CW device and a Bluetooth device, wherein the CW device is connected to the Bluetooth device and the backscattering device respectively;

[0011] The CW device is used to generate and send a second continuous wave;

[0012] The Bluetooth device is also used to receive a second Bluetooth low-power broadcast signal, where the second Bluetooth low-power broadcast signal is a signal reflected by the first target tracking device based on the second continuous wave, and the second Bluetooth low-power broadcast signal includes an identifier of the first target tracking device.

[0013] In some embodiments of the present invention, the CW device comprises: a CW modem, a CW transmitter and a CW antenna, the CW modem is connected to the CW transmitter, the CW transmitter is connected to the CW antenna; the CW modem is connected to the Bluetooth device and the backscatter device respectively;

[0014] The CW modem is used to generate the second continuous wave;

[0015] The CW transmitter is used to send the second continuous wave through the CW antenna.

[0016] In some embodiments of the present invention, the Bluetooth device includes a Bluetooth receiver;

[0017] The CW transmitter and the Bluetooth receiver are configured to be turned on within a first active scanning duration t1, where t1 is within a working period T1 of the CW transmitter.

[0018] In some embodiments of the present invention, the backscattering device is also used to generate the first Bluetooth low energy broadcast signal based on the first continuous wave; determine the first delay based on the first active scanning duration t1; reflect the first Bluetooth low energy broadcast signal according to the first delay; wherein the first delay is less than the t1, and the t1 is within the working cycle T1 of the CW transmitter.

[0019] In some embodiments of the present invention, the first time delay is N times of t1 / n, where N=[0, n-1], and n is a positive integer.

[0020] In some embodiments of the present invention, the tracking device further comprises: a cellular radio frequency device and a Bluetooth device, the cellular radio frequency device being connected to the Bluetooth device and the backscatter device, respectively;

[0021] The cellular radio frequency device is used to generate and send a third continuous wave;

[0022] The Bluetooth device is also used to receive a third Bluetooth low-power broadcast signal, where the third Bluetooth low-power broadcast signal is a signal reflected by the second target tracking device based on the third continuous wave, and the third Bluetooth low-power broadcast signal includes an identifier of the second target tracking device.

[0023] In some embodiments of the present invention, the cellular radio frequency device includes: a cellular modem, a cellular radio frequency front end and a cellular antenna, the cellular modem is connected to the cellular radio frequency front end, the cellular radio frequency front end is connected to the cellular antenna; the cellular modem is connected to the Bluetooth device and the backscatter device respectively;

[0024] The cellular modem is configured to generate the third continuous wave;

[0025] The cellular radio frequency front end is used to send the third continuous wave through the cellular antenna.

[0026] In some embodiments of the present invention, the Bluetooth device includes a Bluetooth receiver;

[0027] The cellular radio frequency front end and the Bluetooth receiver are used to be turned on within a second active scanning duration t2, and t2 is within a working cycle T2 of the cellular radio frequency front end.

[0028] In some embodiments of the present invention, the backscattering device is also used to generate the first Bluetooth low-power broadcast signal based on the first continuous wave; determine the second delay based on the second active scanning duration t2; reflect the first Bluetooth low-power broadcast signal according to the second delay; wherein the second delay is less than the t2, and the t2 is within the working cycle T2 of the cellular RF front end.

[0029] In some embodiments of the present invention, the second time delay is M times of t2 / m, where M=[0, m-1], and m is a positive integer.

[0030] In some embodiments of the present invention, the tracking device further comprises: a Bluetooth device, a switch and a second Bluetooth antenna, the switch and the second Bluetooth antenna being connected;

[0031] The Bluetooth device is used to connect to the second Bluetooth antenna through the switch during a reflection period;

[0032] The backscatter device is used to connect to the second Bluetooth antenna through the switch during a non-reflection period.

[0033] A second aspect of an embodiment of the present invention provides a terminal device, comprising a tracking device as described in the first aspect of the present invention and any optional implementation manner of the first aspect.

[0034] A third aspect of an embodiment of the present invention provides a tracking method, which is applied to a tracking device as described in the first aspect of the present invention and any optional implementation method of the first aspect, or a terminal device as provided in the second aspect of the present invention, and the method includes: receiving a first continuous wave; based on the first continuous wave, reflecting a first Bluetooth low-power broadcast signal, the first Bluetooth low-power broadcast signal including an identifier of the tracking device.

[0035] A third aspect of an embodiment of the present invention provides a computer-readable storage medium, comprising instructions, which, when executed on a computer, enables the computer to execute the method described in the third aspect of the present invention.

[0036] In the technical solution provided in the embodiment of the present invention, the tracking device includes: a backscattering device; a backscattering device for receiving a first continuous wave; based on the first continuous wave, reflecting a first Bluetooth low-power broadcast signal, the first Bluetooth low-power broadcast signal including an identifier of the tracking device. In the embodiment of the present invention, the backscattering technology is adopted to avoid the use of complex Bluetooth data exchange standards and improve the data extraction efficiency. The first Bluetooth low-power broadcast signal includes the identifier of the tracking device, and the identifier of the tracking device can be used to identify the tracking device. Moreover, the use of a backscattering device to receive the first continuous wave and reflect the first Bluetooth low-power broadcast signal is not limited to the number of people, and is also suitable for medium and short distance tracking. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A system architecture diagram for short- to medium-distance contact recording used in an embodiment of the present invention;

[0038] Figure 2 A schematic diagram of an embodiment of a tracking device in an embodiment of the present invention;

[0039] Figure 3A It is a schematic diagram of another embodiment of the tracking device in the embodiment of the present invention;

[0040] Figure 3B It is a schematic diagram of another embodiment of the tracking device in the embodiment of the present invention;

[0041] Figure 3C It is a schematic diagram of another embodiment of the tracking device in the embodiment of the present invention;

[0042] Figure 3D A schematic diagram of the working cycle and active scanning duration of a CW transmitter inside a tracking device in an embodiment of the present invention;

[0043] Figure 3E A schematic diagram of a backscattering time mechanism in an embodiment of the present invention;

[0044] Figure 4A It is a schematic diagram of another embodiment of the tracking device in the embodiment of the present invention;

[0045] Figure 4B It is a schematic diagram of another embodiment of the tracking device in the embodiment of the present invention;

[0046] Figure 4C It is a schematic diagram of another embodiment of the tracking device in the embodiment of the present invention;

[0047] Figure 5A A schematic diagram of an embodiment of a backscattering device in an embodiment of the present invention;

[0048] Figure 5B It is a schematic diagram of another embodiment of the backscattering device in the embodiment of the present invention;

[0049] Figure 5C It is a schematic diagram of another embodiment of the backscattering device in the embodiment of the present invention;

[0050] Figure 6 It is a schematic diagram of another embodiment of the tracking device in the embodiment of the present invention;

[0051] Figure 7 A schematic diagram of an embodiment of a terminal device in an embodiment of the present invention;

[0052] Figure 8 It is a schematic diagram of an embodiment of the tracking method in the embodiment of the present invention. DETAILED DESCRIPTION

[0053] The technical solutions in the embodiments of the present invention will be described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0054] Compared with long-distance tracking such as the Global Positioning System (GPS), close-range tracking has its own unique application points. For example, close-range tracking only obtains information about the tracked object within a certain range. This approach first ensures information security and is not easily eavesdropped by malicious parties. Second, the tracked information includes the relative physical location. For this type of positioning and tracking system, the relative position is more important than the absolute position. For example, the above-mentioned tracking system uses Bluetooth BLE to obtain the historical relative position of a person. Among them, in addition to specific technical applications, the tracking of personnel also needs to consider the convenience of use, such as whether it is necessary to purchase hardware separately and whether complex operations are required during use. The following outlines the advantages and disadvantages of some technologies in close-range tracking of personnel.

[0055] In one implementation, it is item tracking based on Radio Frequency Identification (RFID). Ultra High Frequency (UHF) RFID technology is a wireless electronic tag tracking system specially created for item tracking. This system requires at least one card reader and a large number of electronic tags attached to the surface of the item. At present, UHF RFID technology has not been integrated into smart terminals on a large scale. As an item tracking method, it is fast and can track a large number of items. For example, the Impinj R420 reader can read more than 1,000 electronic tags per second. Moreover, the reading distance is 5-10 meters, which is neither far nor close. However, this tracking method requires professional card readers and electronic tags, which requires additional hardware expenses for ordinary consumers. In addition, UHF RFID adopts Class 1Gen 2 (ISO 18000-6C) tag protocol, which has not been widely integrated into smart terminals, increasing the difficulty of terminal development.

[0056] In another implementation, it is based on Near Field Communication (NFC) object tracking. NFC is widely integrated in smart terminals and is mainly used for applications with high security and short communication distance, such as payment. As for personnel tracking, it has advantages and disadvantages: Advantages: 1. Strong security. 2. Widely integrated with smart terminals, consumers do not need to buy special hardware. Disadvantages: The wireless transmission distance is short, <50cm, not suitable for medium-distance object and personnel tracking.

[0057] In summary, an embodiment of the present invention proposes a system for tracking close-range personnel using backscatter technology, which can also be referred to as a tracking device. The tracking device can be applied to a terminal device to achieve short- to medium-range personnel tracking. The tracking device does not require the user to purchase special hardware and directly uses the terminal device. The terminal device uses backscatter technology to quickly obtain information about other terminal devices within a specified range. Furthermore, the tracking device can use the data structure specified by the Bluetooth BLE standard protocol for data exchange, reduce the research and development cost of the terminal device, and is faster and has a more accurate tracking range than the tracking system in the prior art.

[0058] It can be understood that the terminal equipment in the embodiments of the present invention can be referred to as user equipment (UE), mobile station (MS), mobile terminal equipment (mobile terminal), intelligent terminal equipment, etc., and the terminal equipment can communicate with one or more core networks via a radio access network (RAN). For example, the terminal equipment can be a mobile phone (or "cellular" phone), a computer with a mobile terminal equipment, etc. The terminal equipment can also be a portable, pocket-sized, handheld, computer-built-in or vehicle-mounted mobile device and a terminal equipment in a future NR network, which exchanges voice or data with a radio access network. Description of the terminal equipment: In the present invention, the terminal equipment can also include a relay Relay, and any terminal equipment that can communicate data with a base station can be regarded as a terminal equipment.

[0059] like Figure 1 The figure shows the system architecture diagram of the short-to-medium distance contact recording used in the embodiment of the present invention. Here, a terminal device including a tracking device is used as an example for explanation. The contact history between the terminal device and the terminal device is recorded by using the terminal device to transmit a continuous wave (CW) to obtain the Bluetooth low energy broadcast (BLE Advertising, BLE advertising) signal reflected back by other surrounding terminal devices. Figure 1 As shown, user 0 can be understood as a user using terminal device 0, and user 1, user 2, user 3... user N are similar. Terminal device 0 initiates an inquiry request by transmitting a CW wave. The surrounding terminal devices receive the CW wave and use the CW wave as a carrier to reflect the BLE advertising signal outward. The BLE advertising signal emitted by each terminal device has its unique identification information, and this unique identification information can be used to uniquely identify the terminal device of user N. Terminal device 0 receives BLE information, namely BLE1, BLE2... BLE N, and records the BLE information in terminal device 0.

[0060] It should be noted that, from the perspective of the UHF RFID system, the terminal device in the embodiment of the present invention has the dual functions of a card reader and an electronic tag. The terminal device 0 that transmits CW waves has no authority to rewrite the information content in BLE1, BLE2...BLE N, that is, the BLE information content is only provided by the terminal device that is performing backscattering.

[0061] like Figure 2 , which is a schematic diagram of an embodiment of a tracking device in an embodiment of the present invention. The tracking device comprises: a backscattering device 201; the backscattering device 201 is used to receive a first continuous wave; according to the first continuous wave, reflect a first Bluetooth low-power broadcast signal, wherein the first Bluetooth low-power broadcast signal includes an identifier of the tracking device.

[0062] In an embodiment of the present invention, the tracking device includes a backscattering device 201, that is, the backscattering technology is used to avoid the use of Bluetooth complex data exchange standards and improve data extraction efficiency. The first Bluetooth low-power broadcast signal includes an identifier of the tracking device. The identifier of the tracking device can be used to identify the tracking device. Moreover, the use of the backscattering device 201 to receive the first continuous wave and reflect the first Bluetooth low-power broadcast signal has no limit on the number of people and is also suitable for short and medium distance tracking.

[0063] It can be understood that the backscattering device 201 is responsible for backscattering, that is, using the received CW as a carrier to transmit advertising signals that meet the requirements of the BLE standard through backscattering. When the tracking device backscatters the BLE information, it transmits a unique code (ID) of the tracking device. This ID is similar to the serial number (SN) of the terminal device and has the following characteristics: 1. Uniqueness, each tracking device has a unique ID. 2. It cannot be changed. Once the encapsulation is completed, no person or organization has the ability and authority to change this ID.

[0064] In some embodiments of the present invention, Figure 3A FIG. 2 is a schematic diagram of another embodiment of a tracking device in an embodiment of the present invention. The tracking device may further include: a continuous wave CW device 202 and a Bluetooth device 203, wherein the CW device 202 is connected to the Bluetooth device 203 and the backscattering device 201 respectively;

[0065] CW device 202, for generating and transmitting a second continuous wave;

[0066] The Bluetooth device 203 is also used to receive a second Bluetooth low energy broadcast signal, where the second Bluetooth low energy broadcast signal is a signal reflected by the first target tracking device based on the second continuous wave, and the second Bluetooth low energy broadcast signal includes an identifier of the first target tracking device.

[0067] It is understandable that the Bluetooth device 203 is a Bluetooth module that complies with Bluetooth 4.2 and above standards, including a Bluetooth receiver and a Bluetooth transmitter, which can be simply referred to as a Bluetooth transceiver, and a Bluetooth modem.

[0068] In the embodiment of the present invention, the tracking device can not only receive the first continuous wave and reflect the first Bluetooth low energy broadcast signal through the backscatter device 201, but also generate and send the second continuous wave through the CW device 202 and receive the second Bluetooth low energy broadcast signal reflected by other tracking devices through the Bluetooth device 203. That is, the tracking device can track other tracking devices and can also be tracked by other tracking devices.

[0069] In some embodiments of the present invention, Figure 3B , which is a schematic diagram of another embodiment of a tracking device in an embodiment of the present invention. The CW device 202 may include: a CW modem 2021, a CW transmitter 2022 and a CW antenna 2023, the CW modem 2021 is connected to the CW transmitter 2022, the CW transmitter 2022 is connected to the CW antenna 2023; the CW modem 2021 is connected to the Bluetooth device 203 and the backscatter device 201 respectively;

[0070] CW modem 2021, configured to generate the second continuous wave;

[0071] The CW transmitter 2022 is used to send the second continuous wave through the CW antenna 2023.

[0072] It is understandable that the CW modem 2021 can be understood as a CW core. The CW core is a device for generating CW waves, controlling the generation of CW waves, including defining the CW wave waveform, frequency, on and off time, etc. The CW transmitter 2022 is responsible for converting the digital signal generated from the CW core into an analog signal, filtering and amplifying the analog signal, and transmitting it outward through the CW antenna 2023.

[0073] In the embodiment of the present invention, an implementation method of the internal structure of the CW device 202 is provided, which increases the feasibility of the solution.

[0074] In some embodiments of the present invention, Figure 3C FIG. 2 is a schematic diagram of another embodiment of a tracking device according to an embodiment of the present invention. The Bluetooth device 203 may include a Bluetooth receiver 2031;

[0075] The CW transmitter 2022 and the Bluetooth receiver 2031 are used to be turned on within the first active scanning duration t1, and the t1 is within the working cycle T1 of the CW transmitter 2022. In one embodiment, the starting time of t1 can be the same as the starting time of T1, or can be later than the starting time of T1, and the ending time of t1 is earlier than the ending time of T1. Further, within t1, the CW transmitter 2022 and the Bluetooth receiver 2031 can be turned on at the same time, that is, the CW transmitter 2022 can transmit CW waves, and the Bluetooth receiver 2031 can also synchronously receive Bluetooth low energy broadcast signals.

[0076] In some embodiments of the present invention, the backscattering device 201 is further used to generate the first Bluetooth low energy broadcast signal according to the first continuous wave; determine the first delay according to the first active scanning duration t1; reflect the first Bluetooth low energy broadcast signal according to the first delay; wherein the first delay is less than the t1, and the t1 is within the working cycle T1 of the CW transmitter 2022. Further, the first delay is N times t1 / n, N=[0, n-1], and n is a positive integer.

[0077] In an embodiment, the first time delay determined each time by the backscatter device 201 may be random, or may be determined in the order of N from small to large.

[0078] The following is an example to illustrate: Figure 3D FIG. 1 is a schematic diagram of the working cycle and active scanning duration of the CW transmitter inside the tracking device according to an embodiment of the present invention. Figure 3D As shown, the working cycle of the CW transmitter 2022 is T1. In one T1, the active scanning duration (continuous transmission of CW waves) is t1sweep. In t1sweep, the terminal device can turn on the Bluetooth receiver and the CW transmitter at the same time.

[0079] It is understandable that when the user enables the short-distance contact recording function on the terminal device, or the terminal device automatically starts the short-distance contact recording function. Figure 1 In the system architecture diagram shown, the terminal device 0 (referred to as user 0) that actively transmits CW signals can be understood as a card reader, and other terminal devices that transmit BLE signals through backscatter devices can be understood as tags. Therefore, there is a possibility that the tag signals enter the receiving device of user 0 at the same time, causing signal conflicts, thereby reducing the efficiency of user 0 in identifying tags.

[0080] The embodiment of the present invention proposes a time division mechanism to reduce the impact of multi-tag transmission. Figure 3EAs shown, it is a schematic diagram of the backscattering time mechanism in an embodiment of the present invention. Exemplarily, the first active scanning duration t1 can be equally divided into n time slots s1, s2, s3…sn. The backscattering device in the terminal device N monitors the CW wave. Before backscattering, the processor in the backscattering device randomly generates a delay time (t1delay), which is the first delay mentioned above. The range of t1delay is N*(t1 / n), N=[0, n-1]. The backscattering device can reflect the first Bluetooth low energy broadcast signal according to the t1delay. In this way, for the terminal device 0, the probability of multiple tags working in the same time period is reduced, and signal conflicts are reduced.

[0081] In some embodiments of the present invention, Figure 4A FIG. 2 is a schematic diagram of another embodiment of a tracking device in an embodiment of the present invention. The tracking device may further include: a cellular radio frequency device 204 and a Bluetooth device 203, wherein the cellular radio frequency device 204 is connected to the Bluetooth device 203 and the backscattering device 201 respectively;

[0082] The cellular radio frequency device 204 is used to generate and send a third continuous wave;

[0083] The Bluetooth device 203 is also used to receive a third Bluetooth low energy broadcast signal, where the third Bluetooth low energy broadcast signal is a signal reflected by the second target tracking device based on the third continuous wave, and the third Bluetooth low energy broadcast signal includes an identifier of the second target tracking device.

[0084] In the embodiment of the present invention, the tracking device can not only receive the first continuous wave and reflect the first Bluetooth low-power broadcast signal through the backscatter device 201, but also generate and send the third continuous wave through the cellular radio frequency device 204, and receive the third Bluetooth low-power broadcast signal reflected by other tracking devices through the Bluetooth device 203. That is, the tracking device can track other tracking devices and can also be tracked by other tracking devices. Moreover, the cellular radio frequency device 204 in the tracking device is capable of transmitting CW waves of a certain frequency, so it can replace the dedicated CW device and reduce hardware costs.

[0085] In some embodiments of the present invention, Figure 4B FIG. 2 is a schematic diagram of another embodiment of a tracking device according to an embodiment of the present invention. The cellular radio frequency device 204 may include: a cellular modem 2041, a cellular radio frequency front end 2042 and a cellular antenna 2043. The cellular modem 2041 is connected to the cellular radio frequency front end 2042, and the cellular radio frequency front end 2042 is connected to the cellular antenna 2043; the cellular modem 2041 is connected to the Bluetooth device 203 and the backscatter device 201 respectively;

[0086] A cellular modem 2041, configured to generate the third continuous wave;

[0087] The cellular radio frequency front end 2042 is used to send the third continuous wave through the cellular antenna 2043.

[0088] In the embodiment of the present invention, an implementation method of the internal structure of the cellular radio frequency device 204 is provided, which increases the feasibility of the solution.

[0089] In some embodiments of the present invention, Figure 4C FIG. 2 is a schematic diagram of another embodiment of a tracking device according to an embodiment of the present invention. The Bluetooth device 203 may include a Bluetooth receiver 2031;

[0090] The cellular RF front end 2042 and the Bluetooth receiver 2031 are used to be turned on within the second active scanning duration t2, and the t2 is within the working cycle T2 of the cellular RF front end 2042. In one embodiment, the starting time of t2 can be the same as the starting time of T2, or it can be later than the starting time of T2, and the ending time of t2 is earlier than the ending time of T2. Further, within t2, the cellular RF front end 2042 and the Bluetooth receiver 2031 can be turned on at the same time, that is, the cellular RF front end 2042 can transmit CW waves, and the Bluetooth receiver 2031 can also synchronously receive Bluetooth low energy broadcast signals.

[0091] In some embodiments of the present invention, the backscattering device 201 is further used to generate the first Bluetooth low energy broadcast signal according to the first continuous wave; determine the second delay according to the second active scanning time t2; reflect the first Bluetooth low energy broadcast signal according to the second delay; wherein the second delay is less than the t2, and the t2 is within the working cycle T2 of the cellular radio frequency front end 2042. Further, the second delay is M times t2 / m, M=[0, m-1], and m is a positive integer.

[0092] In an embodiment, the second time delay determined each time by the backscatter device 201 may be random, or may be determined in the order of values ​​of M from small to large.

[0093] It should be noted that the description of the working cycle T2 of the cellular RF front end 2042, the second active scanning duration t2 within T2, and the second delay in the backscattering time mechanism can refer to the working cycle T1 of the CW transmitter 2022, the first active scanning duration t1 within T1 (such as Figure 3D ), and the first delay in the backscattering time mechanism (such as Figure 3E ) are described here and will not be repeated here.

[0094] It can be understood that the above-mentioned first target tracking device and second target tracking device are devices surrounding the tracking device.

[0095] In some embodiments of the present invention, Figure 5A , which is a schematic diagram of an embodiment of a backscattering device in an embodiment of the present invention. The backscattering device 201 may include: a processor 2011, an oscillator 2012, an encoder 2013 and a first Bluetooth antenna 2014, wherein the processor 2011 is connected to the oscillator 2012, the oscillator 2012 is connected to the encoder 2013, and the encoder 2013 is connected to the first Bluetooth antenna 2014;

[0096] The processor 2011 is specifically used to receive the first continuous wave through the first Bluetooth antenna 2014; according to the first continuous wave, control the oscillator 2012 to switch the target frequency, control the encoder 2013 to encode according to the target frequency, and reflect the first Bluetooth low energy broadcast signal through the first Bluetooth antenna 2014.

[0097] It should be noted that the encoder 2013 is a device that implements encoding by changing the impedance matching of the first Bluetooth antenna 2014. For example, the encoder 2013 may be a field effect transistor (FET), etc. The processor 2011 may be a microprocessor, etc., which is not limited here.

[0098] In some embodiments of the present invention, Figure 5B FIG. 2 is a schematic diagram of another embodiment of a backscattering device in an embodiment of the present invention. The backscattering device 201 may further include: a rectifier 2015, the rectifier 2015 is connected to the processor 2011;

[0099] The rectifier 2025 is used to obtain the first continuous wave, convert the first continuous wave into a direct current signal, and start the processor 2011 when the voltage of the direct current signal is higher than a preset threshold.

[0100] In some embodiments of the present invention, the rectifier 2025 may include: a diode and a capacitor, one end of the diode is connected to the first Bluetooth antenna 2014, the other end of the diode is respectively connected to one end of the capacitor and the processor 2011, and the other end of the capacitor is grounded.

[0101] For example, Figure 5CAs shown, it is a schematic diagram of another embodiment of the backscattering device in the embodiment of the present invention. The backscattering device is used to use CW as a carrier to "transmit" a BLE advertising signal. The backscattering device 201 may include a rectifier 2025, a processor 2011, an oscillator 2012, and an encoder 2013. Among them, the encoder 2013 may be a FET switch. The rectifier 2025 is responsible for "monitoring" the CW signal and converting the radio frequency (RF) energy corresponding to the CW signal into a direct current (DC) voltage. When the DC voltage exceeds the limit value, the processor 2011 is awakened and ready for backscattering. During the backscattering process, the processor 2011 controls the oscillator 2012, and the oscillator 2012 controls the FET switch by switching frequencies f1 and f2 to achieve signal encoding that meets the requirements of the BLE tag. It can be understood that the CW signal is one of the cases of RF.

[0102] It should be noted that there is a corresponding relationship between the CW frequency in the embodiment of the present invention and the frequencies f1 and f2 generated by the oscillator 2012 in the backscattering device 201. Here, the example of transmitting a CW signal using a cellular network is used for explanation. For terminal devices supporting 4G LTE and 5G NR and subsequent higher communication levels, 4G B40 and 5G n40 frequency bands are supported. As shown in Table 1 below, the corresponding relationship between the CW frequency and f1 and f2 is shown. In Table 1, 5MHz <f0<50MHz。

[0103]

[0104] Table 1

[0105] It should be noted that in the embodiment of the present invention, since the CW transmitter in the tracking device only transmits CW waves that have not been encoded, there is no problem of increased decoding errors caused by multi-CW conflicts. The problem that may arise is that the superposition (super position) of CWs from different terminals causes the energy radiated to the backscatter receiver to increase or decrease due to different phases. However, in specific applications, even if one transmitter is used to transmit CW waves, the superposition (super position) of CW signals will be caused by reflective objects in the environment, and the superposition effect is unpredictable. Therefore, in order to reduce system complexity, this proposal does not make special treatment for multi-transmitter conflicts.

[0106] In some embodiments of the present invention, the user can freely choose to turn on or off the backscatter device 201, CW device 202, Bluetooth device 203 or cellular radio frequency device 204. If the user chooses to turn on, the tracking device turns on the backscatter device 201, CW device 202, Bluetooth device 203 or cellular radio frequency device 204 accordingly and is in working mode. If the user chooses to turn off, the tracking device turns off the backscatter device 201, CW device 202, Bluetooth device 203 or cellular radio frequency device 204 accordingly, or the backscatter device 201, CW device 202, Bluetooth device 203 or cellular radio frequency device 204 is in sleep mode. The user can make a choice according to actual needs to improve the user experience. When the tracking device does not need to work, it can be turned off or sleep to save power.

[0107] In some embodiments of the present invention, Figure 6 As shown, it is a schematic diagram of another embodiment of the tracking device in the embodiment of the present invention, which may include: the tracking device may also include: a Bluetooth device 203, a switch 205 and a second Bluetooth antenna 206, the switch 205 and the second Bluetooth antenna 206 are connected;

[0108] The Bluetooth device 203 is used to connect to the second Bluetooth antenna 206 via the switch 205 during the reflection period;

[0109] The backscattering device 201 is used to connect to the second Bluetooth antenna 206 through the switch 205 during a non-reflection period.

[0110] It is understandable that the operating frequency of the backscatter device 201 is the same as the operating frequency of the Bluetooth device 203. For example, the backscatter device 201 also operates at the Bluetooth frequency 2.4-2.5 GHz, so the backscatter device 201 and the Bluetooth device 203 can share one antenna.

[0111] Exemplarily, the switch here can be a single pole double throw (SPDT) switch. That is, the SPDT switch can be used to allow the Bluetooth device 203 and the backscatter device 201 to share an antenna. In the default mode, the backscatter device can be connected to the Bluetooth antenna and is ready to reflect signals at any time. After the processor 2011 in the backscatter device 201 determines the time slot for backscattering, the SPDT switch switches the Bluetooth device 203 to the connection in the non-transmitting time slot to "listen" to the reflection information of nearby tags. When the time reaches the transmitting time slot, the SPDT switch switches back to the backscatter device 201 for backscattering.

[0112] like Figure 7 FIG. 1 is a schematic diagram of an embodiment of a terminal device in an embodiment of the present invention, wherein the terminal device may include: Figure 2 , Figure 3A-3C , Figure 4A-4C , Figure 6 A tracking device as described in any one of the above.

[0113] In an embodiment of the present invention, the terminal device can use backscatter technology to quickly record short- and medium-distance contact history information. It provides a new solution for processing contact history of people like Covid-19. Compared with traditional Bluetooth technology, this technology obtains information faster and can obtain more personnel information at the same time. Moreover, the use of backscatter technology avoids the use of complex Bluetooth data exchange standards and improves data extraction efficiency. The recording of short- and medium-distance contact history is realized from the hardware data interaction definition.

[0114] like Figure 8 FIG. 1 is a schematic diagram of an embodiment of a tracking method in an embodiment of the present invention. The method is applied to a tracking device as described in an embodiment of the present invention, or a terminal device as described in an embodiment of the present invention, wherein the terminal device includes a tracking device, and the tracking device includes a backscattering device (see Figure 2 ), the method comprising:

[0115] 801. Receive a first continuous wave.

[0116] The tracking device receives the first continuous wave through the backscatter device.

[0117] In one embodiment, the backscatter device includes: a processor, an oscillator, an encoder and a first Bluetooth antenna (see Figure 5A ), the processor is connected to the oscillator, the oscillator is connected to the encoder, and the encoder is connected to the first Bluetooth antenna. The tracking device receives the first continuous wave through the first Bluetooth antenna, and the processor obtains the first continuous wave.

[0118] In one embodiment, the backscattering device further comprises: a rectifier (see Figure 5B ), the rectifier is connected to the processor; the tracking device obtains the first continuous wave through the rectifier, converts the first continuous wave into a DC voltage, and starts the processor when the DC voltage is higher than a preset threshold.

[0119] 802. Reflect a first Bluetooth low energy broadcast signal according to the first continuous wave, where the first Bluetooth low energy broadcast signal includes an identifier of the tracking device.

[0120] The tracking device reflects a first Bluetooth low-power broadcast signal based on the first continuous wave through a backscatter device, and the first Bluetooth low-power broadcast signal includes an identifier of the tracking device.

[0121] In one embodiment, the processor controls the oscillator to switch the target frequency according to the first continuous wave, controls the encoder to encode according to the target frequency, and reflects the first Bluetooth low energy broadcast signal through the first Bluetooth antenna.

[0122] (1) In one implementation, the tracking device further includes: a continuous wave CW device and a Bluetooth device (see Figure 3A ), the CW device is connected to the Bluetooth device and the backscatter device respectively; the tracking device generates and sends a second continuous wave through the CW device; the tracking device receives a second Bluetooth low-power broadcast signal through the Bluetooth device, the second Bluetooth low-power broadcast signal is a signal reflected by the first target tracking device according to the second continuous wave, and the second Bluetooth low-power broadcast signal includes the identification of the first target tracking device.

[0123] In one embodiment, the CW device includes: a CW modem, a CW transmitter and a CW antenna (see Figure 3B ), the CW modem is connected to the CW transmitter, and the CW transmitter is connected to the CW antenna; the CW modem is connected to the Bluetooth device and the backscatter device respectively; the tracking device generates the second continuous wave through the CW modem; the tracking device uses the CW transmitter to send the second continuous wave through the CW antenna.

[0124] In one embodiment, the Bluetooth device includes a Bluetooth receiver (see Figure 3C ); The tracking device can turn on the CW transmitter and the Bluetooth receiver within the first active scanning duration t1, and the t1 is within the working cycle T1 of the CW transmitter (refer to Figure 3D ).

[0125] In one embodiment, the tracking device generates the first Bluetooth low energy broadcast signal according to the first continuous wave through the backscattering device; determines the first delay according to the first active scanning duration t1; reflects the first Bluetooth low energy broadcast signal according to the first delay; wherein the first delay is less than t1, and t1 is within the working cycle T1 of the CW transmitter. Furthermore, the first delay is N times t1 / n (refer to Figure 3E ), N = [0, n-1], n is a positive integer.

[0126] (2) In another implementation, the tracking device further includes: a cellular radio frequency device and a Bluetooth device (see Figure 4A), the cellular radio frequency device is connected to the Bluetooth device and the backscatter device respectively; the tracking device generates and sends a third continuous wave through the cellular radio frequency device; the tracking device receives a third Bluetooth low-power broadcast signal through the Bluetooth device, the third Bluetooth low-power broadcast signal is a signal reflected by the second target tracking device according to the third continuous wave, and the third Bluetooth low-power broadcast signal includes the identification of the second target tracking device.

[0127] In one embodiment, the cellular radio frequency device includes: a cellular modem, a cellular radio frequency front end and a cellular antenna (see Figure 4B ), the cellular modem is connected to the cellular RF front end, and the cellular RF front end is connected to the cellular antenna; the cellular modem is connected to the Bluetooth device and the backscatter device respectively; the tracking device generates the third continuous wave through the cellular modem; the tracking device uses the cellular RF front end to send the third continuous wave through the cellular antenna.

[0128] In one embodiment, the Bluetooth device includes a Bluetooth receiver (see Figure 4C ); The tracking device can turn on the cellular radio frequency front end and the Bluetooth receiver within the second active scanning duration t2, and the t2 is within the working cycle T2 of the cellular radio frequency front end (refer to Figure 3D ).

[0129] In one embodiment, the tracking device generates the first Bluetooth low energy broadcast signal according to the first continuous wave through the backscattering device; determines the second delay according to the second active scanning time t2; reflects the first Bluetooth low energy broadcast signal according to the second delay; wherein the second delay is less than t2, and t2 is within the working cycle T2 of the cellular radio frequency front end. Furthermore, the second delay is M times t2 / m (refer to Figure 3E ), M = [0, m-1], m is a positive integer.

[0130] In some embodiments of the present invention, the tracking device further includes: a Bluetooth device, a switch and a second Bluetooth antenna (see Figure 6 ), the switch is connected to the second Bluetooth antenna; the tracking device is connected to the second Bluetooth antenna through the switch via the Bluetooth device during the reflection period; the tracking device is connected to the second Bluetooth antenna through the switch via the backscattering device during the non-reflection period.

[0131] It should be noted that Figure 8 For the relevant contents in the illustrated embodiment, please refer to the above description of the tracking device, which will not be elaborated here.

[0132] In an embodiment of the present invention, the tracking device includes a backscattering device, that is, the backscattering technology is used to avoid the use of Bluetooth complex data exchange standards and improve data extraction efficiency. The first Bluetooth low-power broadcast signal includes an identifier of the tracking device. The identifier of the tracking device can be used to identify the tracking device. Moreover, the use of a backscattering device to receive the first continuous wave and reflect the first Bluetooth low-power broadcast signal has no limit on the number of people and is also suitable for medium and short distance tracking.

[0133] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center to another website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that a computer can store or a data storage device such as a server or data center that includes one or more available media integrated. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)), etc.

[0134] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

Claims

1. A tracking device, characterized in that: include: Backscatter device; The backscattering device is used to receive the first continuous wave; reflecting a first Bluetooth low energy broadcast signal according to the first continuous wave, wherein the first Bluetooth low energy broadcast signal includes an identifier of the tracking device; in, The tracking device further includes a continuous wave CW device and a Bluetooth device, wherein the CW device is connected to the Bluetooth device and the backscattering device respectively; the CW device is used to generate and send a second continuous wave; the Bluetooth device is used to receive a second Bluetooth low-power broadcast signal; wherein the second Bluetooth low-power broadcast signal is a signal reflected by the first target tracking device according to the second continuous wave, and the second Bluetooth low-power broadcast signal includes an identifier of the first target tracking device; or, The tracking device also includes a cellular radio frequency device and a Bluetooth device, and the cellular radio frequency device is connected to the Bluetooth device and the backscattering device respectively; the cellular radio frequency device is used to generate and send a third continuous wave; the Bluetooth device is used to receive a third Bluetooth low-power broadcast signal; wherein, the third Bluetooth low-power broadcast signal is a signal reflected by the second target tracking device based on the third continuous wave, and the third Bluetooth low-power broadcast signal includes the identification of the second target tracking device.

2. The tracking device according to claim 1, characterized in that: The backscatter device comprises: a processor, an oscillator, an encoder and a first Bluetooth antenna, wherein the processor is connected to the oscillator, the oscillator is connected to the encoder, and the encoder is connected to the first Bluetooth antenna; The processor is specifically used to receive the first continuous wave through the first Bluetooth antenna; according to the first continuous wave, control the oscillator to switch the target frequency, control the encoder to encode according to the target frequency, and reflect the first Bluetooth low-power broadcast signal through the first Bluetooth antenna.

3. The tracking device according to claim 2, characterized in that: The backscatter device further includes: a rectifier, the rectifier being connected to the processor; The rectifier is used to obtain the first continuous wave, convert the first continuous wave into a direct current signal, and start the processor when the voltage of the direct current signal is higher than a preset threshold.

4. The tracking device according to any one of claims 1 to 3, characterized in that: When the tracking device further includes the continuous wave CW device and the Bluetooth device, the CW device includes: a CW modem, a CW transmitter and a CW antenna, the CW modem is connected to the CW transmitter, the CW transmitter is connected to the CW antenna; the CW modem is connected to the Bluetooth device and the backscatter device respectively; The CW modem is used to generate the second continuous wave; The CW transmitter is used to send the second continuous wave through the CW antenna.

5. The tracking device according to claim 4, characterized in that: The Bluetooth device includes a Bluetooth receiver; The CW transmitter and the Bluetooth receiver are configured to be turned on within a first active scanning duration t1, where t1 is within a working period T1 of the CW transmitter.

6. The tracking device according to claim 4, characterized in that: The backscattering device is further used to generate the first Bluetooth low energy broadcast signal according to the first continuous wave; determine the first delay according to the first active scanning time length t1; and reflect the first Bluetooth low energy broadcast signal according to the first delay; The first time delay is smaller than t1, and t1 is within a working period T1 of the CW transmitter.

7. The tracking device according to claim 6, characterized in that: The first time delay is N times of t1 / n, where N=[0, n-1], and n is a positive integer.

8. The tracking device according to any one of claims 1 to 3, characterized in that: When the tracking device further includes the cellular radio frequency device and the Bluetooth device, the cellular radio frequency device includes: a cellular modem, a cellular radio frequency front end and a cellular antenna, the cellular modem is connected to the cellular radio frequency front end, and the cellular radio frequency front end is connected to the cellular antenna; the cellular modem is connected to the Bluetooth device and the backscatter device respectively; The cellular modem is configured to generate the third continuous wave; The cellular radio frequency front end is used to send the third continuous wave through the cellular antenna.

9. The tracking device according to claim 8, characterized in that The Bluetooth device includes a Bluetooth receiver; The cellular radio frequency front end and the Bluetooth receiver are used to be turned on within a second active scanning duration t2, and t2 is within a working cycle T2 of the cellular radio frequency front end.

10. The tracking device according to claim 8, characterized in that The backscattering device is further used to generate the first Bluetooth low energy broadcast signal according to the first continuous wave; determine the second delay according to the second active scanning time length t2; and reflect the first Bluetooth low energy broadcast signal according to the second delay; The second time delay is smaller than t2, and t2 is within a working period T2 of the cellular RF front end.

11. The tracking device according to claim 10, characterized in that: The second time delay is M times of t2 / m, where M=[0, m-1], and m is a positive integer.

12. The tracking device according to claim 1, characterized in that The tracking device further comprises: a switch and a second Bluetooth antenna, wherein the switch and the second Bluetooth antenna are connected; The Bluetooth device is used to connect to the second Bluetooth antenna through the switch during a reflection period; The backscatter device is used to connect to the second Bluetooth antenna through the switch during a non-reflection period.

13. A terminal device, characterized in that: The terminal device comprises a tracking apparatus as described in any one of claims 1-12.

14. A tracking method, characterized in that: The method is applied to the tracking device according to any one of claims 1 to 12, or the terminal device according to claim 13, and the method comprises: Receive the first continuous wave; reflecting a first Bluetooth low energy broadcast signal according to the first continuous wave, wherein the first Bluetooth low energy broadcast signal includes an identifier of the tracking device; Wherein, the method further comprises: Generate and send a second continuous wave; and receive a second Bluetooth low-power broadcast signal; wherein the second Bluetooth low-power broadcast signal is a signal reflected by the first target tracking device based on the second continuous wave, and the second Bluetooth low-power broadcast signal includes an identifier of the first target tracking device; or, Generate and send a third continuous wave; and receive a third Bluetooth low-power broadcast signal; wherein the third Bluetooth low-power broadcast signal is a signal reflected by the second target tracking device based on the third continuous wave, and the third Bluetooth low-power broadcast signal includes an identifier of the second target tracking device.

15. A computer-readable storage medium comprising instructions, which, when executed on a computer, causes the computer to perform the method of claim 14.

16. A computer program product comprising instructions which, when executed on a computer, cause the computer to perform the method as claimed in claim 14.

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