CN115997430A

CN115997430A - Relative phase determination for frequency drift compensation

Info

Publication number: CN115997430A
Application number: CN202080103571.1A
Authority: CN
Inventors: 徐朝军; 沈钢; 高飞; 王权; 李留海; 张留涛; 林侃
Original assignee: Nokia Shanghai Bell Co Ltd; Nokia Solutions and Networks Oy
Current assignee: Nokia Shanghai Bell Co Ltd; Nokia Solutions and Networks Oy
Priority date: 2020-08-25
Filing date: 2020-08-25
Publication date: 2023-04-21
Also published as: WO2022040927A1

Abstract

Embodiments of the present disclosure relate to devices, methods, apparatuses, and computer-readable storage media for relative phase determination for frequency drift compensation. The method includes obtaining, at a first device, a first reference signal associated with a reference antenna from a second device for a first period of time and a second reference signal associated with the reference antenna for a second period of time subsequent to the first period of time; and determining a phase relationship between the reference antenna and at least one target antenna based at least on the first reference signal and the second reference signal, the at least one target antenna and the reference antenna being located in the same antenna array. In this way, compensation of frequency drift can be achieved based on the determination of the relative phase, which is crucial for positioning accuracy and stability in high accuracy BLE AoA/AoD positioning solutions.

Description

Relative phase determination for frequency drift compensation

Technical Field

Embodiments of the present disclosure relate generally to the field of telecommunications and, more particularly, relate to an apparatus, method, device, and computer-readable storage medium for relative phase determination for frequency drift compensation.

Background

Reliable and accurate location services are key points for internet of things (IoT) applications such as asset tracking, smart manufacturing, public safety, and the like. By capturing and processing environmental information, the system may improve work efficiency and enhance security concerns by monitoring employee behavior and self-awareness of the environment. Consumers would benefit from personalized contextual information and services, as well as new services such as smart city public safety.

To facilitate the intellectualization of factories, location Based Services (LBS) with low cost and high accuracy will be an important value added service. Bluetooth Low Energy (BLE) provides a viable technology for indoor positioning. In particular, direction finding solutions based on angle of arrival (AoA) and angle of departure (AoD) were introduced, which may provide positioning techniques for high accuracy positioning in two or three dimensions.

Disclosure of Invention

In general, example embodiments of the present disclosure provide a solution for relative phase determination for frequency drift compensation.

In a first aspect, a first device is provided. The first device includes at least one processor; at least one memory including computer program code; the at least one memory and the computer program code are configured to, with the at least one processor, cause the first device to at least: obtaining, from a second device, a first reference signal associated with a reference antenna for a first period of time and a second reference signal associated with the reference antenna for a second period of time subsequent to the first period of time; and determining a phase relationship between the reference antenna and at least one target antenna based at least on the first reference signal and the second reference signal, the at least one target antenna and the reference antenna being located in the same antenna array.

In a second aspect, a method is provided. The method includes obtaining, at a first device, a first reference signal associated with a reference antenna from a second device for a first period of time and a second reference signal associated with the reference antenna for a second period of time subsequent to the first period of time; and determining a phase relationship between the reference antenna and at least one target antenna based at least on the first reference signal and the second reference signal, the at least one target antenna and the reference antenna being located in the same antenna array.

In a third aspect, an apparatus is provided that includes means for obtaining, at a first apparatus, a first reference signal associated with a reference antenna from a second apparatus over a first period of time and a second reference signal associated with the reference antenna over a second period of time after the first period of time; and means for determining a phase relationship between the reference antenna and at least one target antenna based at least on the first reference signal and the second reference signal, the at least one target antenna and the reference antenna being located in the same antenna array.

In a fourth aspect, there is provided a computer readable medium having stored thereon a computer program which, when executed by at least one processor of a device, causes the device to perform a method according to the second aspect.

Other features and advantages of embodiments of the present disclosure will become apparent from the following description of the specific embodiments, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the embodiments of the disclosure.

Drawings

Embodiments of the present disclosure are presented in an exemplary sense and their advantages are explained in more detail below with reference to the drawings, in which

FIG. 1 illustrates an example environment in which example embodiments of the present disclosure may be implemented;

FIG. 2 illustrates a flowchart of an example method for relative phase determination for frequency drift compensation, according to some example embodiments of the present disclosure;

fig. 3A and 3D illustrate examples of antenna switching modes according to some example embodiments of the present disclosure;

fig. 4A and 4B illustrate examples of virtual signal reconstruction and relative phase determination according to some example embodiments of the present disclosure;

FIG. 5 illustrates a simplified block diagram of a device suitable for implementing exemplary embodiments of the present disclosure; and

fig. 6 illustrates a block diagram of an example computer-readable medium, according to some embodiments of the disclosure.

The same or similar reference numbers will be used throughout the drawings to refer to the same or like elements.

Detailed Description

Principles of the present disclosure will now be described with reference to some example embodiments. It should be understood that these embodiments are described for illustrative purposes only and to assist those skilled in the art in understanding and practicing the present disclosure, and are not intended to limit the scope of the present disclosure in any way. The disclosure described herein may be implemented in a variety of ways other than those described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

References in the present disclosure to "one embodiment," "an example embodiment," etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in connection with an example embodiment, it is submitted that it is within the knowledge of one skilled in the art to effect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It will be understood that, although the terms "first" and "second," etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish between the functionality of the various elements. As used herein, the term "and/or" includes any and all combinations of one or more of the listed terms.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises," "comprising," "has," "including" and/or "having," when used herein, specify the presence of stated features, elements, and/or components, but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof.

As used in this application, the term "circuitry" may refer to one or more or all of the following:

(a) Hardware-only circuit implementations (such as analog and/or digital circuitry-only implementations) and

(b) A combination of hardware circuitry and software, such as (if applicable):

(i) Combination of analog and/or digital hardware circuit(s) and software/firmware, and

(ii) Any portion of the hardware processor(s) work together with software (including digital signal processor(s), software, and memory(s) to cause a device such as a mobile phone or server to perform various functions), and

(c) Hardware circuit(s) and/or processor(s) such as microprocessor(s) or part of microprocessor(s) that require software (e.g., firmware) to run, but the software may not exist when it is not needed for operation.

This definition of circuitry applies to all uses of this term in this application, including all uses in any claims. As a further example, as used in this application, the term circuitry also encompasses hardware-only circuitry or a processor (or multiple processors) or a portion of hardware circuitry or a processor and its (or their) implementation in conjunction with software and/or firmware. For example and where applicable to the elements of the specific claims, the term circuitry also includes a baseband integrated circuit or processor integrated circuit for a mobile device, or a similar integrated circuit in a server, a cellular network device, or other computing or network device.

As used herein, the term "communication network" refers to a network that conforms to any suitable communication standard, such as a fifth generation (5G) system, long Term Evolution (LTE), LTE-advanced (LTE-a), wideband Code Division Multiple Access (WCDMA), high Speed Packet Access (HSPA), narrowband internet of things (NB-IoT), and so forth. Furthermore, communication between the terminal device and the network device in the communication network may be performed according to any suitable generation communication protocol, including, but not limited to, first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, future fifth generation (5G) New Radio (NR) communication protocols and/or any other protocols currently known or developed in the future. Embodiments of the present disclosure may be applied in various communication systems. In view of the rapid development of communications, there will of course also be future types of communication technologies and systems that may embody the present disclosure. The scope of the present disclosure should not be considered limited to only the systems described above.

As used herein, the term "network device" refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. A network device may refer to a Base Station (BS) or an Access Point (AP), such as a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), a NR next generation NodeB (gNB), a Remote Radio Unit (RRU), a Radio Head (RH), a Remote Radio Head (RRH), a relay, a low power node (such as femto, pico, etc.), depending on the terminology and technology applied. The RAN split architecture includes a gNB-CU (centralized unit, hosting RRC, SDAP, and PDCP) that controls multiple gNB-DUs (distributed units, hosting RLC, MAC, and PHY). The relay node may correspond to the DU portion of the IAB node.

The term "terminal device" refers to any terminal device that may be capable of wireless communication. By way of example, and not limitation, a terminal device may also be referred to as a communication device, a User Equipment (UE), a Subscriber Station (SS), a portable subscriber station, a Mobile Station (MS), or an Access Terminal (AT). The terminal devices may include, but are not limited to, mobile phones, cellular phones, smart phones, voice over IP (VoIP) phones, wireless local loop phones, tablets, wearable terminal devices, personal Digital Assistants (PDAs), portable computers, desktop computers, image capture terminal devices (such as digital cameras), gaming terminal devices, music storage and playback devices, in-vehicle wireless terminal devices, wireless endpoints, mobile stations, laptop embedded devices (LEEs), laptop mounted devices (LMEs), USB dongles, smart devices, wireless Customer Premises Equipment (CPE), internet of things (IoT) devices, watches or other wearable devices, head Mounted Displays (HMDs), vehicles, drones, medical devices and applications (e.g., tele-surgery), industrial devices and applications (e.g., robots and/or other wireless devices operating in an industrial and/or automated processing chain environment), consumer electronic devices, devices operating in a commercial and/or industrial wireless network, and the like. The terminal device may also correspond to a Mobile Terminal (MT) part of an Integrated Access and Backhaul (IAB) node (also referred to as a relay node). In the following description, the terms "terminal device", "communication device", "terminal", "user equipment" and "UE" may be used interchangeably.

While in various example embodiments, the functionality described herein may be performed in a fixed and/or wireless network node, in other example embodiments, the functionality may be implemented in a user equipment device (such as a cell phone or tablet or notebook or desktop or mobile internet of things device or fixed internet of things device). The user equipment device may, for example, be suitably equipped with corresponding capabilities as described in connection with the fixed and/or wireless network node(s). The user equipment device may be a user equipment and/or a control device such as a chipset or processor, which when installed therein is configured to control the user equipment. Examples of such functionality include a bootstrapping server function and/or a home subscriber server, which may be implemented in a user equipment device by providing the user equipment device with software configured to cause the user equipment device to execute from the perspective of these functions/nodes.

Fig. 1 illustrates an example communication network 100 in which embodiments of the present disclosure may be implemented. As shown in fig. 1, the communication network 100 includes a receiving device 110 (hereinafter also referred to as a first device 110) and a transmitting device 120 (hereinafter also referred to as a second device 120). The transmitting device 120 may be in communication with the receiving device 110. It will be appreciated that the number of network devices and terminal devices shown in fig. 1 is not limited thereto. Fig. 1 is given for illustrative purposes and does not imply any limitation. Communication network 100 may include any suitable number of network devices and terminal devices. Further, it should be understood that in some cases, the receiving device 110 may be referred to as a terminal device and the transmitting device 120 may be referred to as a network device. In some cases, the receiving device 110 may be referred to as a network device and the transmitting device 120 may be referred to as a terminal device.

Depending on the communication technology, network 100 may be a Code Division Multiple Access (CDMA) network, a Time Division Multiple Access (TDMA) network, a Frequency Division Multiple Access (FDMA) network, an Orthogonal Frequency Division Multiple Access (OFDMA) network, a single carrier frequency division multiple access (SC-FDMA) network, or any other network. The communications discussed in network 100 may conform to any suitable standard, including, but not limited to, new radio access (NR), long Term Evolution (LTE), evolved LTE, LTE-advanced (LTE-a), wideband Code Division Multiple Access (WCDMA), code Division Multiple Access (CDMA), CDMA2000, global system for mobile communications (GSM), and the like. Further, the communication may be performed according to any generation communication protocol currently known or developed in the future. Examples of communication protocols include, but are not limited to, first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, fifth generation (5G) communication protocols. The techniques described herein may be used for the wireless networks and radio technologies mentioned above and other wireless networks and radio technologies. For clarity, certain aspects of the technology are described below for LTE, and LTE terminology is used in much of the description below.

In a direction-finding solution, the measurement of the relative phase between different antennas of an antenna array is crucial for the accuracy of the AoA/AoD estimation. However, BLE has only one RF chain for low cost. Thus, switchable antenna arrays are used to transmit Constant Tone Extension (CTE) signals in an AoD scenario or to receive CTE signals in an AoA scenario. The CTE signal is a sine wave with a frequency of 250 KHz. In the receiving device, the phase of each antenna is measured based on CTE signals received in different time slots.

In order to calculate the relative phase between two given antennas, it is necessary to estimate the phase of one antenna during the time slot when the other antenna is in an active state. For example, for a 2 antenna array, it is generally assumed that the frequency of the received CTE signal remains unchanged in one packet. Unfortunately, this assumption does not hold due to frequency drift of the transmitting device and the receiving device. The frequency drift may be as high as 20KHz, which will result in an average error in the relative phase calculation of up to + -15 degrees.

The present invention therefore proposes a solution for relative phase determination for frequency drift compensation. In this solution, a reference antenna may be used to transmit or receive reference signals. By means of the reference signal, a virtual signal associated with the reference antenna may be generated. Based on the virtual signal and the target signal associated with the target antenna in the antenna array, the relative phases of the target antenna and the reference antenna may be determined. In this way, compensation of frequency drift can be achieved based on the determination of the relative phase, which is crucial for positioning accuracy and stability in high accuracy BLE AoA/AoD positioning solutions.

The principles and implementations of the present invention are described in detail below in conjunction with fig. 2-6. Fig. 2 illustrates a flowchart of an example method 200 for relative phase determination for frequency drift compensation, according to some example embodiments of the present disclosure. The method 200 may be implemented at a receiving device 110 as shown in fig. 1. For ease of discussion, the method 200 will be described with reference to FIG. 1.

As shown in fig. 2, at 210, the receiving device 110 obtains a first reference signal associated with a reference antenna for a first period of time and a second reference signal associated with the reference antenna for a second period of time from the transmitting device 120. It should be appreciated that the first time period and the second time period may be continuous. For example, the second period of time follows the first period of time.

In some example embodiments, the antenna array may be located at the receiving device 110, and a certain antenna in the antenna array may be designated as a reference antenna. In this case, the receiving device 110 may be regarded as a network device, and the transmitting device 120 may be regarded as a terminal device. The transmitting device 120 may transmit a reference signal (such as the CTE signal mentioned above) to the receiving device 110. The receiving device 110 may receive the reference signal via a reference antenna. The receiving device 110 may obtain the first reference signal and the second reference signal in different sampling time periods. For example, the receiving device 110 may receive a first reference signal via a reference antenna during a first period of time and a second reference signal via the reference antenna during a second period of time.

In some example embodiments, an antenna array may be located at the transmitting device 120, and a certain antenna in the antenna array may be designated as a reference antenna. In this case, the receiving device 110 may be regarded as a terminal device, and the transmitting device 120 may be regarded as a network device. A reference signal, such as the CTE signal mentioned above, may be transmitted from the reference antenna of the transmitting device 120 to the receiving device 110. The receiving device 110 may obtain the first reference signal and the second reference signal in different sampling time periods. For example, the receiving device 110 may receive a first reference signal transmitted from a reference antenna during a first period of time and a second reference signal transmitted from the reference antenna during a second period of time.

Referring back to fig. 2, at 220, the receiving device 110 determines a phase relationship between the reference antenna and the at least one target antenna based at least on the first reference signal and the second reference signal. The at least one target antenna and the reference antenna may be located in the same antenna array. That is, if the reference antenna is located at the receiving device 110, at least one target antenna is also located at the receiving device 110. If the reference antenna is located at the transmitting device 120, at least one target antenna is also located at the transmitting device 120. At least one target antenna may also transmit or receive CTE signals in the time slots in which it is active.

The antennas of the antenna array may operate in different modes, which may be referred to as an antenna switching mode design. The antenna switching pattern may indicate: to receive or transmit CTE signals, which antenna of the antenna array, e.g. which of the reference antenna and the at least one target antenna, is to be activated in each time slot. Allowing one of the antennas in the antenna array to be activated in a single time slot.

Fig. 3A and 3D illustrate examples of antenna switching modes according to some example embodiments of the present disclosure.

Fig. 3A and 3B show RAR antenna switching patterns of a 3 antenna array and a 7 antenna array, respectively. In the RAR type antenna switching mode, one of every two slots is allocated to a reference antenna, and the remaining slots are equally allocated to a target antenna.

For example, as shown in fig. 3A, for a three antenna array, there is one reference antenna 352 and two

target antennas

351 and 353. Switching of antennas may be performed in switching

slots

321, 322 and

sampling slots

331, 332. During the handover procedure, the reference antenna 352 and the

target antenna

351 or 353 may be alternately activated. The reference antenna 352 and the

target antenna

351 or 353 may transmit/receive CTE signals during their active periods. There is a switching slot (slots 341-348) between each active time period of the reference antenna 352 and the

target antenna

351 or 353. Since a slot for the target antenna 351 or 353 (i.e., the target antenna A1 or A2) may be embedded between two slots for the reference antenna 352 (i.e., the reference antenna R), an antenna unit of the RAR may be formed, and thus such an antenna switching mode may be referred to as an RAR type mode.

For a 7 antenna array as shown in fig. 3B, there is one reference antenna 352 and 7 target antennas 351 and 353-357. Switching of antennas may be performed in switching

slots

321, 322 and

sampling slots

331, 332. During the handover procedure, the reference antenna 352 and one of the target antennas 351 and 353-357 may be alternately activated. The reference antenna 352 and the target antennas 351 and 353-357 may transmit/receive CTE signals during their active periods. There is a switching time slot (time slots 361-372) between each active time period of the reference antenna 352 and one of the target antennas 351 and 353-357.

Fig. 3C and 3D show RAAR antenna switching patterns of 3 antenna array and 7 antenna array, respectively. In the RAAR type antenna switching mode, one of every three slots is allocated to a reference antenna, and the remaining slots are equally allocated to other antennas.

For example, as shown in fig. 3C, for a three antenna array, there is one reference antenna 352 and two

target antennas

351 and 353. Switching of antennas may be performed in switching

slots

321, 322 and

sampling slots

331, 332. The reference antenna 352 and the

target antenna

351 or 353 may transmit/receive CTE signals during their active periods. There is one switching slot (slots 373-378) between each active period of the reference antenna 352 and the

target antenna

351 or 353. During the handover procedure, the time slots of the two target antennas 351 and 353 (i.e., target antennas A1 or A2) may be embedded between every two time slots for the reference antenna 352 (i.e., reference antenna R). The antenna elements of the RAAR may be formed and thus such an antenna switching mode may be referred to as a RAAR type mode.

For an antenna array as shown in fig. 3D, there is one reference antenna 352 and 7 target antennas 351 and 353-357. Switching of antennas may be performed in switching

slots

321, 322 and

sampling slots

331, 332. The reference antenna 352 and the target antennas 351 and 353-357 may transmit/receive CTE signals during their active periods. There is a switching time slot (time slots 381-389) between each active time period of the reference antenna 352 and one of the target antennas 351 and 353-357. During the handoff process, two time slots in target antennas 351 and 353-357 may be embedded between every two time slots for reference antenna 352.

Fig. 4A and 4B illustrate examples of virtual signal reconstruction and relative phase determination according to some example embodiments of the present disclosure. Hereinafter, for the RAR type mode and the RAAR type mode, determination of the relative phase between the reference antenna and the target antenna may be described as follows in connection with fig. 4A and 4B.

In both the AoD scenario and the AoA scenario, the CTE signal may be sampled as a composite signal at the receiving device 110. As mentioned above, the receiving device 110 may obtain a first reference signal associated with the reference antenna during a first time period and a second reference signal associated with the reference antenna during a second time period.

For the RAR mode, for example, as shown in fig. 4A, the receiving device 110 may obtain a first reference signal 406 associated with a reference antenna in the slot 401 and a second reference signal 409 associated with the reference antenna in the slot 405.

The receiving device 110 may also obtain a target signal associated with the target antenna for a third time period after the first time period and before the second time period. For example, as shown in fig. 4A, the target signal 408 may be obtained in a time slot 403.

The receiving device 110 may generate a virtual signal associated with the reference antenna corresponding to the third time period based on the first reference signal and the second reference signal. Fig. 4A also shows a virtual signal 407 generated based on the first reference signal 406 and the second reference signal 409.

In some example embodiments, the virtual signal 407 may be generated based on the reference initial phase 412 of the virtual signal 407 and the target frequency of the target signal 408. The target frequency of the target signal 408 may be measured by the receiving device 11O. The reference initial phase 412 of the virtual signal 407 may be determined based on at least the first reference frequency and the reference termination phase 411 of the first reference signal 406 and the second reference frequency and the reference initial phase 413 of the second reference signal 409.

In some example embodiments, the reference initial phase 412 of the virtual signal 407 may be determined by:

wherein phi represents the reference initial phase of the virtual signal _R1 Represents the reference termination phase, phi _R2 Representing another reference initial phase, f _R1 Represents a first reference frequency, f _R2 Representing a second reference frequency, T _SW Representing a switching time interval between transmission of the target signal and transmission of the first reference signal or the second reference signal, f _A Represents the target frequency, and T _A Representing the duration of the third time period.

Based on the reference initial phase 412 of the virtual signal 407 and the target frequency of the target signal 408, the virtual signal 407 may be determined as follows:

φ _V (t)＝2πf _A t+φ (2)

the receiving device 110 may determine a phase difference between the target signal 408 and the virtual signal 407 and determine a phase relationship between the reference antenna and the target antenna based on the phase difference. For example, the phase relationship may be referred to as a phase difference, i.e., the relative phase between the reference antenna and the target antenna. Relative phase phi _AR (t) may be determined by:

φ _AR (t)＝φ _A (t)-φ _V (t) (3)

wherein phi is _A (t) may represent the original phase of the target signal in time slot 403.

As shown in fig. 3A, the target signal 408 may be associated with either of

antennas

351 and 353 of a 3 antenna array as shown in fig. 3A or any of antennas 351 and 353-357 of a 7 antenna array as shown in fig. 3B. In a similar manner, the receiving device 110 may determine the relative phase between the reference antenna and each target antenna. The receiving device 110 may also determine an average relative phase based on the determined relative phases.

For RAAR-type mode, for example, as shown in fig. 4B, receiving device 110 may obtain a first reference signal 421 associated with a reference antenna in slot 411 and a second reference signal 426 associated with a reference antenna in slot 417.

The receiving device 110 may also obtain a target signal associated with the target antenna for a third time period after the first time period and before the second time period and obtain a second target signal associated with the second target antenna for a fourth time period after the first time period and before the second time period.

For example, as shown in fig. 4B, a first target signal 423 may be obtained in time slot 413 and a second target signal 424 may be obtained in time slot 415.

The receiving device 110 may generate a first virtual signal associated with the reference antenna corresponding to the third time period and a second virtual signal associated with the reference antenna corresponding to the fourth time period based on the first reference signal and the second reference signal. Fig. 4B also shows virtual signals 422 and 425 generated based on the first reference signal 421 and the second reference signal 426.

In some example embodiments, the first virtual signal 422 may be generated based on the reference initial phase 415 of the virtual signal 422 and the first target frequency of the first target signal 423. The first virtual signal 425 may be generated based on the reference initial phase 416 of the virtual signal 425 and the second target frequency of the second target signal 424.

The first target frequency of the first target signal 423 and the second target frequency of the second target signal 424 may be measured by the receiving device 110. The reference initial phase 415 of the virtual signal 422 and the reference initial phase 416 of the virtual signal 425 may be determined based at least on the first reference frequency and the reference termination phase 414 of the first reference signal 421 and the second reference frequency and the reference initial phase 417 of the second reference signal 426.

In some example embodiments, the reference initial phase 415 of the virtual signal 422 may be determined by:

Wherein phi is ₁ Representing a first virtualFirst reference initial phase of signal phi _R1 Represents the reference termination phase, phi _R2 Representing another reference initial phase, f _R1 Represents a first reference frequency, f _R2 Representing a second reference frequency, T _SW Representing the time interval between the transmission of a first target signal and the transmission of a first reference signal or the time interval between the transmission of a second target signal and the transmission of a second reference signal, f _A1 Representing a first target frequency, f _A2 Represents a second target frequency, and T _A Representing the total duration of the third and fourth time periods.

In some example embodiments, the reference initial phase 416 of the virtual signal 425 may be determined by:

wherein phi is ₂ A second reference initial phase phi representing a second virtual signal _R1 Represents the reference termination phase, phi _R2 Representing another reference initial phase, f _R1 Represents a first reference frequency, f _R2 Representing a second reference frequency, T _SW Representing the time interval between the transmission of a first target signal and the transmission of a first reference signal or the time interval between the transmission of a second target signal and the transmission of a second reference signal, f _A1 Representing a first target frequency, f _A2 Represents a second target frequency, and T _A Representing the total duration of the third and fourth time periods.

Based on the reference initial phase 415 of the virtual signal 422 and the first target frequency of the first target signal 423, the virtual signal 422 may be determined as follows:

φ _V1 (t)＝2πf _A1 t+φ ₁ (6)

based on the reference initial phase 416 of the virtual signal 425 and the second target frequency of the second target signal 424, the virtual signal 425 may be determined as follows:

φ _V2 (t)＝2πf _A2 t+φ ₂ (7)

the receiving device 110 may then determine the phase difference between the target signal 423 and the virtual signal 422, and the phase difference between the target signal 424 and the virtual signal 425. The relative phase between the reference antenna and the target antenna associated with the target signal 423 may be determined based on the phase difference between the target signal 423 and the virtual signal 422. The relative phase between the reference antenna and the target antenna associated with the target signal 424 may be determined based on the phase difference between the target signal 424 and the virtual signal 425.

Relative phase phi between the reference antenna and the target antenna associated with the target signal 423 _A1R (t) may be determined by:

φ _A1R (t)＝φ _A1 (t)-φ _V1 (t) (8)

relative phase phi between the reference antenna and the target antenna associated with the target signal 424 _A2R (t) may be determined by:

φ _A2R (t)＝φ _A2 (t)-φ _V2 (t) (9)

wherein phi is _A1 (t) and phi _A2 (t) indicates the original phases of the target signals received in time slots 413 and 415, respectively.

The target signals 423 and 425 may be associated with any two of

antennas

351 and 353 of a 3 antenna array as shown in fig. 3A or antennas 351 and 353-357 of a 7 antenna array as shown in fig. 3B, respectively. In a similar manner, the receiving device 110 may determine the relative phase between the reference antenna and each target antenna. The receiving device 110 may also determine an average relative phase based on the determined relative phases.

In this way, compensation of frequency drift can be achieved based on the determination of the relative phase, which is crucial for positioning accuracy and stability in high accuracy BLE AoA/AoD positioning solutions.

The residual relative phase error after frequency drift compensation by using the solution of the present disclosure can be enumerated as follows.

Table 1: residual relative phase error (in degrees)

As shown in table 1, the residual error is reduced to below 2 degrees for 3 antenna arrays and below 5 degrees for 7 antenna arrays. Thereby improving the accuracy and stability of direction finding.

In some example embodiments, an apparatus capable of performing the method 200 (e.g., implemented at the receiving device 110) may include means for performing the respective steps of the method 200. The component may be implemented in any suitable form. For example, the components may be implemented in a circuit or software module.

In some example embodiments, the apparatus includes means for obtaining, at a first device, a first reference signal associated with a reference antenna from a second device over a first period of time and a second reference signal associated with the reference antenna over a second period of time after the first period of time; and means for determining a phase relationship between the reference antenna and at least one target antenna based at least on the first reference signal and the second reference signal, the at least one target antenna and the reference antenna being located in the same antenna array. During the course of the handover procedure,

fig. 5 is a simplified block diagram of an apparatus 500 suitable for implementing embodiments of the present disclosure. Device 500 may be provided to implement a communication device, such as receiving device 110 shown in fig. 1. As shown, device 500 includes one or more processors 510, one or more memories 550 coupled to processor 510, and one or more transmitters and/or receivers (TX/RX) 540 coupled to processor 510.

TX/RX 540 is used for two-way communication. TX/RX 540 has at least one antenna to facilitate communication. The communication interface may represent any interface required to communicate with other network elements.

Processor 510 may be of any type suitable for a local technology network and may include, by way of non-limiting example, one or more of the following: general purpose computers, special purpose computers, microprocessors, digital Signal Processors (DSPs), and processors based on a multi-core processor architecture. The device 500 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock that is synchronized to the master processor.

Memory 520 may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memory include, but are not limited to, read-only memory (ROM) 524, electrically programmable read-only memory (EPROM), flash memory, hard disks, compact Disks (CD), digital Video Disks (DVD), and other magnetic and/or optical storage devices. Examples of volatile memory include, but are not limited to, random Access Memory (RAM) 522 and other volatile memory that does not last for the duration of the power outage.

The computer program 530 includes computer-executable instructions that are executed by an associated processor 510. Program 530 may be stored in ROM 520. Processor 510 may perform any suitable actions and processes by loading program 530 into RAM 520.

Embodiments of the present disclosure may be implemented by means of program 530 such that device 500 may perform any of the processes of the present disclosure as discussed with reference to fig. 2-4B. Embodiments of the present disclosure may also be implemented in hardware or by a combination of hardware and software.

In some embodiments, program 530 may be tangibly embodied in a computer-readable medium, which may be included in device 500 (such as in memory 520) or other storage device accessible to device 500. Device 500 may load program 530 from a computer readable medium into RAM 522 for execution. The computer readable medium may include any type of tangible, non-volatile memory, such as ROM, EPROM, flash memory, hard disk, CD, DVD, etc. Fig. 6 shows an example of a computer readable medium 600 in the form of a CD or DVD. The computer readable medium has a program 530 stored thereon.

In general, the various embodiments of the disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of the embodiments of the disclosure are illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor to perform the method 200 as described above with reference to fig. 2. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform particular tasks or implement particular abstract data types. In various embodiments, the functionality of the program modules may be combined or split between program modules as desired. Machine-executable instructions for program modules may be executed within a local device or within a distributed device. In distributed devices, program modules may be located in both local and remote memory storage media.

Program code for carrying out the methods of the present disclosure may be written in any combination of one or more programming languages. These program code may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus such that the program code, when executed by the processor or controller, causes the functions/operations specified in the flowchart and/or block diagram to be implemented. The program code may execute entirely on the machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of this disclosure, computer program code or related data may be carried by any suitable carrier to enable an apparatus, device, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer readable media, and the like.

The computer readable medium may be a computer readable signal medium or a computer readable storage medium. The computer readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Moreover, although operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In some scenarios, multitasking and parallel processing may be advantageous. Likewise, while the above discussion contains several specific implementation details, these should not be construed as limitations on the scope of the disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination.

Although the disclosure has been described in language specific to structural features and/or methodological acts, it is to be understood that the disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A first device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code are configured to, with the at least one processor, cause the first device to at least:

obtaining, from a second device, a first reference signal associated with a reference antenna for a first period of time, and a second reference signal associated with the reference antenna for a second period of time subsequent to the first period of time; and

a phase relationship between the reference antenna and at least one target antenna is determined based at least on the first reference signal and the second reference signal, the at least one target antenna and the reference antenna being located in a same antenna array.

2. The first device of claim 1, wherein the first device comprises the antenna array, and wherein the first device is caused to obtain the first reference signal and the second reference signal by:

receiving the first reference signal via the reference antenna of the first device during the first time period; and

the second reference signal is received via the reference antenna during the second time period.

3. The first device of claim 1, wherein the second device comprises the antenna array, and wherein the first device is caused to obtain the first reference signal and the second reference signal by:

receiving the first reference signal transmitted from the reference antenna of the second device during the first time period; and

the second reference signal transmitted from the reference antenna is received within the second time period.

4. The first device of claim 1, wherein the at least one target antenna comprises a single target antenna, and wherein the first device is caused to determine the phase relationship by:

obtaining a target signal associated with the target antenna from the second device during a third time period after the first time period and before the second time period;

generating a virtual signal associated with the reference antenna corresponding to the third time period based on the first reference signal and the second reference signal;

determining a phase difference between the target signal and the virtual signal; and

the phase relationship is determined based on the phase difference.

5. The first device of claim 4, wherein the first device is caused to generate the virtual signal by:

determining a reference initial phase of the virtual signal based on the first reference signal and the second reference signal;

determining a target frequency of the target signal; and

the virtual signal is generated based on the reference initial phase and the target frequency.

6. The first device of claim 5, wherein the first device is caused to determine the reference initial phase by:

determining a first reference frequency and a reference termination phase of the first reference signal;

determining a second reference frequency and another reference initial phase of the second reference signal; and

the reference initial phase of the virtual signal is determined based on the first reference frequency, the reference termination phase, the second reference frequency, and the further reference initial phase.

7. The first device of claim 6, wherein the reference initial phase of the virtual signal is determined by:

wherein phi represents the reference initial phase of the virtual signal _R1 Represents the reference termination phase, phi _R2 Representing the further reference initial phase, f _R1 Representing the first reference frequency, f _R2 Representing the second reference frequency, T _SW Representing a time interval between transmission of the target signal and transmission of the first reference signal or the second reference signal, f _A Represents the target frequency, and T _A Representing the duration of the third time period.

8. The first device of claim 1, wherein the at least one target antenna comprises a first target antenna and a second target antenna, and wherein the first device is caused to determine the phase relationship by:

obtaining a first target signal associated with the first target antenna from the second device during a third time period after the first time period and before the second time period;

obtaining a second target signal associated with the second target antenna from the second device for a fourth time period after the first time period and before the second time period, the fourth time period being different from the third time period;

generating a first virtual signal associated with the reference antenna corresponding to the third time period and a second virtual signal associated with the reference antenna corresponding to the fourth time period based on the first reference signal and the second reference signal;

Determining a first phase difference between the first signal and the first virtual signal, and a second phase difference between the second signal and the second virtual signal; and

the phase relationship is determined based on the first phase difference and the second phase difference.

9. The first device of claim 8, wherein the first device is caused to generate the first virtual signal by:

determining a first reference initial phase of the first virtual signal and a second reference initial phase of the second virtual signal based on the first reference signal and the second reference signal;

determining a first target frequency of the first target signal and a second target frequency of the second target signal; and

the first virtual signal is generated based on the first reference initial phase and the first target frequency, and the second virtual signal is generated based on the second reference initial phase and the second target frequency.

10. The first device of claim 9, wherein the first device is caused to determine the first reference initial phase and the second reference initial phase by:

the first reference initial phase and the second reference initial phase are determined based on the first reference frequency, the reference termination phase, the second reference frequency, and the further reference initial phase.

11. The first device of claim 10, wherein the first reference initial phase of the first virtual signal is determined by:

wherein phi is ₁ Representing the first reference initial phase, phi, of the first virtual signal _R1 Represents the reference termination phase, phi _R2 Representing the further reference initial phase, f _R1 Representing the first reference frequency, f _R2 Representing the second reference frequency, T _SW Representing a time interval between transmission of the first target signal and transmission of the first reference signal, or a time interval between transmission of the second target signal and transmission of the second reference signal, f _A1 Representing the first target frequency, f _A2 Represents the second target frequency, and T _A Representing the total duration of the third time period and the fourth time period.

12. The first device of claim 10, wherein the second reference initial phase of the second virtual signal is determined by:

wherein phi is ₂ Representing the second reference initial phase, phi, of the second virtual signal _R1 Represents the reference termination phase, phi _R2 Representing the further reference initial phase, f _R1 Representing the first reference frequency, f _R2 Representing the second reference frequency, T _SW Representing a time interval between transmission of the first target signal and transmission of the first reference signal, or a time interval between transmission of the second target signal and transmission of the second reference signal, f _A1 Representing the first target frequency, f _A2 Represents the second target frequency, and TA represents the total duration of the third time period and the fourth time period.

13. The first device of claim 1, wherein the first device comprises a receiving device and the second device comprises a transmitting device.

14. A method, comprising:

obtaining, at a first device, a first reference signal associated with a reference antenna from a second device for a first period of time, and a second reference signal associated with the reference antenna for a second period of time subsequent to the first period of time; and

15. The method of claim 14, wherein the first device comprises the antenna array, and wherein obtaining the first reference signal and the second reference signal comprises:

16. The method of claim 14, wherein the second device comprises the antenna array, and wherein obtaining the first reference signal and the second reference signal comprises:

17. The method of claim 14, wherein the at least one target antenna comprises a single target antenna, and wherein determining the phase relationship comprises:

the phase relationship is determined based on the phase difference.

18. The method of claim 17, wherein generating the virtual signal comprises:

determining a target frequency of the target signal; and

19. The method of claim 18, wherein determining a reference initial phase comprises:

20. The method of claim 19, wherein the reference initial phase of the virtual signal is determined by:

wherein phi represents the virtual letterThe reference initial phase of the number phi _R1 Represents the reference termination phase, phi _R2 Representing the further reference initial phase, f _R1 Representing the first reference frequency, f _R2 Representing the second reference frequency, T _SW Representing a time interval between transmission of the target signal and transmission of the first reference signal or the second reference signal, f _A Represents the target frequency, and T _A Representing the duration of the third time period.

21. The method of claim 14, wherein the at least one target antenna comprises a first target antenna and a second target antenna, and wherein determining the phase relationship comprises:

22. The method of claim 21, wherein generating the first virtual signal comprises:

23. The method of claim 22, wherein determining the first reference initial phase and the second reference initial phase comprises:

24. The method of claim 23, wherein the first reference initial phase of the first virtual signal is determined by:

wherein phi is ₁ Representing the first reference initial phase, phi, of the first virtual signal _R1 Represents the reference termination phase, phi _R2 Representing the further reference initial phase, f _R1 Representing the first reference frequency, f _R2 Representing the second reference frequency, T _SW Representing a time interval between transmission of the first target signal and transmission of the first reference signal, or the second target signalA time interval between transmission of the second reference signal and transmission of f _A1 Representing the first target frequency, f _A2 Represents the second target frequency, and T _A Representing the total duration of the third time period and the fourth time period.

25. The method of claim 23, wherein the second reference initial phase of the second virtual signal is determined by:

wherein phi is ₂ Representing the second reference initial phase, phi, of the second virtual signal _R1 Represents the reference termination phase, phi _R2 Representing the further reference initial phase, f _R1 Representing the first reference frequency, f _R2 Representing the second reference frequency, T _SW Representing a time interval between transmission of the first target signal and transmission of the first reference signal, or a time interval between transmission of the second target signal and transmission of the second reference signal, f _A1 Representing the first target frequency, f _A2 Represents the second target frequency, and T _A Representing the total duration of the third time period and the fourth time period.

26. The method of claim 14, wherein the first device comprises a receiving device and the second device comprises a transmitting device.

27. An apparatus, comprising:

means for obtaining, at a first device, a first reference signal associated with a reference antenna from a second device for a first period of time, and a second reference signal associated with the reference antenna for a second period of time subsequent to the first period of time; and

Means for determining a phase relationship between the reference antenna and at least one target antenna based at least on the first reference signal and the second reference signal, the at least one target antenna and the reference antenna being located in a same antenna array.

28. A non-transitory computer readable medium comprising program instructions for causing an apparatus to perform at least the method of any one of claims 14-26.