Real-time analog front-end response estimation for sensing applications

Abstract

Embodiments of apparatus, systems, and methods for wireless devices to perform improved channel estimation for sensing applications such as ranging are presented herein. The wireless device may determine noise characteristics (e.g., a spectrum of noise variance on a channel) and may use the noise characteristics to estimate a response of an analog front end of the wireless device. The wireless device may correct the channel estimate based on the estimated response of the analog front end.

Description

Technical Field

[0001] The present application relates to wireless devices, and more particularly to apparatus, systems and methods for channel estimation for sensing applications. Background Art

[0002] The use of wireless communication systems is growing rapidly. In addition, wireless communication technology has evolved from voice communications only to also include the transmission of data such as the Internet and multimedia content.

[0003] Mobile electronic devices may take the form of smartphones or tablets that are commonly carried by users. Wearable devices (also known as accessory devices) are a newer form of mobile electronic device, an example being a smartwatch. In addition, low-cost, low-complexity wireless devices intended for static or dynamic deployment are also increasing rapidly as part of the development of the "Internet of Things". In other words, the complexity, capabilities, traffic patterns and other characteristics of the devices required are becoming increasingly broad.

[0004] One use case for wireless communications includes sensing applications, such as estimating the distance or angle between multiple devices. For example, ranging can provide the distance between one wireless device and another wireless device. However, existing wireless communication technologies may have poor performance. Therefore, improvements in this area are desired. Summary of the invention

[0005] In particular, embodiments of systems, apparatus, and methods for wireless devices to perform sensing with improved channel estimation, such as in ranging (time of flight) applications, are presented herein.

[0006] According to the techniques described herein, a first wireless device may initiate a sensing process with a second wireless device. The first wireless device may receive a channel estimation sequence and / or other data from the second device for use in the sensing process. The first wireless device may estimate the channel excluding a channel response of an analog front end (AFE) of the first wireless device. For example, the first wireless device may determine an estimate of an AFE response based on an estimate of a variance of thermal noise, and may use the estimated AFE response to correct an estimate of an overall channel.

[0007] The techniques described herein may be implemented in and / or used with a number of different types of devices, including, but not limited to, cellular telephones, tablet computers, accessories and / or wearable computing devices, portable media players, vehicles, access points and other wireless local area network equipment, cellular base stations and other cellular network infrastructure equipment, servers, and any of a variety of other computing devices.

[0008] This summary is intended to provide a brief overview of some of the topics described in this document. Therefore, it should be understood that the above features are only examples and should not be construed as narrowing the scope or essence of the topics described herein in any way. Other features, aspects, and advantages of the topics described herein will become apparent through the following detailed description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] A better understanding of the embodiments disclosed herein may be obtained when the following detailed description is considered in conjunction with the following drawings, in which:

[0010] Figure 1 illustrating an exemplary wireless communication system according to some embodiments;

[0011] Figure 2 illustrates a base station (BS) in communication with a user equipment (UE) device according to some embodiments;

[0012] Figure 3 An exemplary block diagram of a UE according to some embodiments is shown;

[0013] Figure 4 illustrates an exemplary block diagram of a BS according to some embodiments;

[0014] Figure 5 illustrates an exemplary block diagram of a cellular communication circuit according to some embodiments;

[0015] Figure 6 and Figure 7 illustrates an example of a 5G NR base station (gNB) according to some embodiments;

[0016] Figure 8 Two wireless devices are shown executing a sensing application according to some embodiments;

[0017] Fig. 9 is a flow chart illustrating an exemplary method for performing real-time analog front-end response estimation according to some embodiments;

[0018] Fig.10 An exemplary block diagram illustrating a wireless device estimating a channel according to some embodiments; and

[0019] Fig.11 is a communication flow diagram illustrating an exemplary sensing application according to some embodiments.

[0020] Although the present invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and described in detail herein. However, it should be understood that the drawings and detailed description thereof are not intended to limit the invention to the particular forms disclosed, but on the contrary, the purpose is to cover all modifications, equivalents and alternative forms falling within the spirit and scope of the invention as defined by the appended claims. DETAILED DESCRIPTION

[0021] the term

[0022] The following is a glossary of terms used in this patent application:

[0023] Storage media —Any of various types of non-transitory memory devices or storage devices. The term "memory medium" is intended to include installation media, for example, CD-ROM, floppy disk or tape devices; computer system memory or random access memory such as DRAM, DDR RAM, SRAM, EDO RAM, Rambus RAM, etc.; non-volatile memory such as flash memory, magnetic media, for example, hard disk drive or optical storage device; registers or other similar types of memory elements, etc. The memory medium may also include other types of non-transitory memory or combinations thereof. In addition, the memory medium may be located in the first computer system executing the program, or may be located in a different second computer system connected to the first computer system via a network such as the Internet. In the latter case, the second computer system may provide program instructions to the first computer for execution. The term "memory medium" may include two or more memory media that may reside in different locations in different computer systems connected, for example, via a network. The memory medium may store program instructions (e.g., expressed as a computer program) that may be executed by one or more processors.

[0024] Carrier medium —Memory media as described above, and physical transmission media, such as buses, networks and / or other physical transmission media that transmit signals (such as electrical signals, electromagnetic signals or digital signals).

[0025] Programmable hardware components - Includes a variety of hardware devices that include multiple programmable function blocks connected via programmable interconnects. Examples include FPGAs (field programmable gate arrays), PLDs (programmable logic devices), FPOAs (field programmable object arrays), and CPLDs (complex PLDs). Programmable function blocks can vary from fine-grained (combinational logic units or lookup tables) to coarse-grained (arithmetic logic units or processor cores). Programmable hardware elements may also be referred to as "configurable logic units."

[0026] Computer Systems —Any of various types of computing or processing systems, including a personal computer system (PC), a mainframe computer system, a workstation, a network appliance, an Internet appliance, a personal digital assistant (PDA), a television system, a grid computing system, or other devices or combinations of devices. In general, the term "computer system" can be broadly defined to encompass any device (or combination of devices) having at least one processor that executes instructions from a memory medium.

[0027] User Equipment (UE) (or "UE Device") —Any of various types of computer system devices that are mobile or portable and perform wireless communication. Examples of UE devices include mobile phones or smart phones (e.g., iPhone TM , based on Android TM phones), portable gaming devices (e.g., Nintendo DS TM , PlayStation Portable TM 、Gameboy Advance TM , iPhone TM ), laptops, wearable devices (e.g., smart watches, smart glasses), PDAs, portable Internet devices, music players, data storage devices or other handheld devices, etc. In general, the term "UE" or "UE device" can be broadly defined to cover any electronic device, computing device and / or telecommunication device (or combination of devices) that can be easily transmitted by a user and capable of wireless communication.

[0028] Wireless Devices - Any of various types of computer system devices that perform wireless communication. A wireless device may be portable (or mobile), or may be stationary or fixed at a certain location. A UE is an example of a wireless device.

[0029] Communications equipment —Any of various types of computer systems or devices that perform communication, where the communication may be wired or wireless. A communication device may be portable (or mobile), or may be stationary or fixed at a certain location. A wireless device is an example of a communication device. A UE is another example of a communication device. A communication device may be referred to as a station or STA.

[0030] Base station or access point (AP) - The term "base station" has the full scope of its ordinary meaning and includes at least a wireless communication station installed at a fixed location and used to communicate as part of a wireless telephone system or radio system. The term "access point" is used similarly.

[0031] Link budget limited—includes the full scope of its ordinary meaning and includes at least the characteristics of a wireless device (e.g., UE) that exhibits limited communication capabilities or limited power relative to a device that is not link budget limited or relative to a device for which a radio access technology (RAT) standard has been developed. A link budget limited wireless device may experience relatively limited receive capabilities and / or transmit capabilities, which may be due to one or more factors, such as device design, device size, battery size, antenna size or design, transmit power, receive power, current transmission medium conditions, and / or other factors. Such devices may be referred to herein as "link budget limited" (or "link budget constrained") devices. A device may be inherently link budget limited due to the size of the device, battery power, and / or transmit / receive power. For example, a smart watch that communicates with a base station via LTE or LTE-A may be inherently link budget limited due to its reduced transmit / receive power and / or antenna reduction. Wearable devices such as smart watches are generally link budget limited devices. Alternatively, a device may not be inherently link budget limited, e.g., may have sufficient size, battery power, and / or transmit / receive power for normal communication over LTE or LTE-A, but may be temporarily link budget limited due to current communication conditions, e.g., a smartphone at a cell edge, etc. It is noted that the term "link budget limited" includes or encompasses power limitations, and thus a link-limited device may be considered a link budget limited device.

[0032] Processing Elements —refers to various elements or combinations of elements. Processing elements include, for example, circuits such as ASICs (application specific integrated circuits), portions or circuits of individual processor cores, entire processor cores, individual processors, programmable hardware devices (such as field programmable gate arrays (FPGAs)), and / or larger portions of systems including multiple processors.

[0033] Wi-Fi —The term "Wi-Fi" has the full scope of its ordinary meaning and includes at least wireless communication networks or RATs that are served by wireless LAN (WLAN) access points and provide connectivity to the Internet through these access points. Most modern Wi-Fi networks (or WLAN networks) are based on the IEEE 802.11 standard and are marketed under the name "Wi-Fi". Wi-Fi (WLAN) networks are different from cellular networks. Wi-Fi or WLAN may refer to technologies based on IEEE 802.11 wireless standards (such as 802.11a, 802.11.b, 802.11g, 802.11n, 802.11-2012, 802.11ac, 802.11ad, 802.11ax, 802.11ay, 802.11az and / or other IEEE 802.11 standards).

[0034] automatic —refers to the performance of an action or operation by a computer system (e.g., software executed by a computer system) or a device (e.g., a circuit, a programmable hardware element, an ASIC, etc.) without the need for the action or operation to be directly specified or performed by a user input. Thus, the term "automatically" is in contrast to the manual performance or specification of an operation by a user, where the user provides input to directly perform the operation. An automatic process may be initiated by input provided by a user, but the subsequent actions performed "automatically" are not specified by the user, i.e., are not performed "manually," where the user specifies each action to be performed. For example, a user filling out an electronic form by selecting each field and providing input specifying information (e.g., by typing in information, selecting check boxes, radio selections, etc.) is manually filling out the form, even though the computer system must update the form in response to user actions. The form may be automatically filled out by a computer system, where the computer system (e.g., software executed on the computer system) analyzes the fields of the form and fills out the form without any user input specifying the answers to the fields. As indicated above, a user may invoke the automatic filling out of a form, but not participate in the actual filling out of the form (e.g., the user does not manually specify the answers to the fields but they are automatically completed). This specification provides various examples of operations that are automatically performed in response to actions taken by a user.

[0035] Configured as --Various components may be described as being "configured to" perform one or more tasks. In such environments, "configured to" is a broad statement that generally means "having a structure" that performs one or more tasks during operation. Thus, even when the component is not currently performing the task, the component can be configured to perform the task (e.g., a set of electrical conductors can be configured to electrically connect a module to another module even when the two modules are not connected). In some contexts, "configured to" can be a broad statement that generally means "having a structure" that performs one or more tasks during operation. Thus, even when the component is not currently turned on, the component can be configured to perform the task. Typically, the circuitry that forms the structure corresponding to "configured to" may include hardware circuitry.

[0036] For ease of description, various components may be described as performing one or more tasks. Such descriptions should be interpreted as including the phrase "configured to". The description of a component being configured to perform one or more tasks is expressly intended to not invoke the interpretation of the sixth paragraph of Section 112 of Title 35 of the United States Code on that component.

[0037] Figure 1 and Figure 2 —Communications system

[0038] Figure 1 A simplified exemplary wireless communication system according to some embodiments is shown. Note that Figure 1The system is only one example of possible systems, and features of the present disclosure may be implemented in any of a variety of systems as desired.

[0039] As shown, the exemplary wireless communication system includes one or more base stations 102, such as base station 102A, which communicate with one or more user equipment 106A, 106B to 106N, etc. through a transmission medium. Each user equipment may be referred to as "user equipment" (UE) in this article. Therefore, user equipment 106 is referred to as UE or UE device.

[0040] Base station (BS) 102 may be a base transceiver station (BTS) or a cell site ("cellular base station") and may include hardware that enables wireless communications with user equipment 106A-106N.

[0041] The communication area (or coverage area) of a base station may be referred to as a "cell". The base station 102 and the UE 106 may be configured to communicate over a transmission medium using any of a variety of RATs, which are also referred to as wireless communication technologies or telecommunication standards, such as Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS) (associated with, for example, Wideband Code Division Multiple Access (WCDMA) or Time Division Synchronous Code Division Multiple Access (TD-SCDMA) air interfaces), LTE, Long Term Evolution-Advanced (LTE-A), 5G New Radio (5G NR), High Speed ​​Packet Access (HSPA), 3GPP2 (3rd Generation Partnership Project 2) Code Division Multiple Access 2000 (CDMA2000) (e.g., Radio Transmission Technology (1xRTT), Evolution-Data Optimized (1xEV-DO), High Speed ​​Packet Data (HRPD), Enhanced High Speed ​​Packet Data (eHRPD)), etc. It should be noted that if the base station 102 is implemented in the context of LTE, it may alternatively be referred to as 'eNodeB' or 'eNB'. It should be noted that if the base station 102 is implemented in the context of 5G NR, it may alternatively be referred to as 'gNodeB' or 'gNB'.

[0042] As shown, base station 102 may also be configured to communicate with network 100 (e.g., a core network of a cellular service provider, a telecommunications network such as a public switched telephone network (PSTN), and / or the Internet, among other possibilities). Thus, base station 102 may facilitate communications between user devices and / or between user devices and network 100. In particular, cellular base station 102 may provide UE 106 with various telecommunication capabilities such as voice, short message service (SMS), and / or data services.

[0043] Base station 102 and other similar base stations operating according to the same or different cellular communication standards may thus provide a network of cells that can provide continuous or nearly continuous overlapping service to UEs 106A-106N and similar devices over a geographic area via one or more cellular communication standards.

[0044] Thus, although base station 102 may function as Figure 1 106A-106N, but each UE 106 may also be able to receive signals from (and possibly be within communication range of) one or more other cells (possibly provided by other base stations 102B-102N), which may be referred to as "neighboring cells". Such cells may also be able to facilitate communications between user devices and / or between user devices and network 100. Such cells may include "macro" cells, "micro" cells, "pico" cells, and / or cells of any various other granularity of service area size. Other configurations are also possible.

[0045] In some embodiments, base station 102 may be a next generation base station, e.g., a 5G New Radio (5G NR) base station, or "gNB". In some embodiments, a gNB may be connected to a legacy Evolved Packet Core (EPC) network and / or to a New Radio Communications Core (NRC) network. In addition, a gNB cell may include one or more Transition and Reception Points (TRPs). In addition, a UE capable of operating in accordance with 5G NR may be connected to one or more TRPs within one or more gNBs.

[0046] It should be noted that UE 106 is capable of communicating using multiple wireless communication standards. For example, in addition to at least one cellular communication protocol (e.g., GSM, UMTS (associated with, for example, WCDMA or TD-SCDMA air interface), LTE, LTE-A, 5G NR, HSPA, 3GPP2CDMA2000 (e.g., 1xRTT, 1xEV-DO, HRPD, eHRPD), etc.), UE 106 can be configured to communicate using wireless networking (e.g., Wi-Fi) and / or peer-to-peer wireless communication protocols (e.g., Bluetooth, Wi-Fi peer-to-peer, etc.). If desired, UE 106 can also or alternatively be configured to communicate using one or more global navigation satellite systems (GNSS, such as GPS or GLONASS), one or more mobile television broadcast standards (e.g., Advanced Television Systems Committee-Mobile / Handheld (ATSC-M / H)), and / or any other wireless communication protocol. Other combinations of wireless communication standards (including more than two wireless communication standards) are also possible.

[0047] Figure 2A user equipment 106 (e.g., one of devices 106A-106N) is shown in accordance with some embodiments in communication with base station 102. UE 106 may be a device with cellular communication capabilities, such as a mobile phone, handheld device, computer or tablet computer, or virtually any type of wireless device.

[0048] UE 106 may include a processor configured to execute program instructions stored in a memory. UE 106 may perform any of the method embodiments described herein by executing such stored instructions. Alternatively or in addition, UE 106 may include a programmable hardware element, such as a field programmable gate array (FPGA) configured to perform any of the method embodiments described herein or any portion of any of the method embodiments described herein.

[0049] UE 106 may include one or more antennas for communicating using one or more wireless communication protocols or technologies. In some embodiments, UE 106 may be configured to communicate using, for example, CDMA2000 (1xRTT, 1xEV-DO, HRPD, eHRPD) or LTE using a single shared radio component and / or GSM or LTE using a single shared radio component. The shared radio component may be coupled to a single antenna, or may be coupled to multiple antennas (e.g., for multiple input, multiple output or "multiple input-multiple output" (MIMO) antenna systems) for performing wireless communications. Typically, the radio component may include any combination of a baseband processor, an analog radio frequency (RF) signal processing circuit (e.g., including filters, mixers, trackers, oscillators, amplifiers, etc.) or a digital processing circuit (e.g., for digital modulation and other digital processing). Similarly, the radio component may use the aforementioned hardware to implement one or more receiving chains and transmitting chains. For example, UE 106 may share one or more parts of a receiving chain and / or transmitting chain between multiple wireless communication technologies such as those discussed above.

[0050] In some embodiments, UE 106 may include any number of antennas and may be configured to use the antennas to transmit and / or receive directional wireless signals (e.g., beams). Similarly, BS 102 may also include any number of antennas and may be configured to use the antennas to transmit and / or receive directional wireless signals (e.g., beams). In order to receive and / or transmit such directional signals, the antennas of UE 106 and / or BS 102 may be configured to apply different "weights" to different antennas. The process of applying these different weights may be referred to as "precoding".

[0051] In some embodiments, UE 106 may include a separate transmit chain and / or receive chain (e.g., including separate antennas and other radio components) for each wireless communication protocol configured to communicate with it. As another possibility, UE 106 may include one or more radio components shared between multiple wireless communication protocols, and one or more radio components used uniquely by a single wireless communication protocol. For example, UE 106 may include a shared radio component for communicating using either LTE or 5GNR (or LTE or 1xRTT, or LTE or GSM), and a separate radio component for communicating using each of Wi-Fi and Bluetooth. Other configurations are also possible.

[0052] Figure 3 —UE block diagram

[0053] Figure 3 An exemplary simplified block diagram of a communication device 106 according to some embodiments is shown. Note that Figure 3 The block diagram of the communication device is only an example of a possible communication device. According to the embodiment, in addition to other devices, the communication device 106 can be a user equipment (UE) device, a mobile device or a mobile station, a wireless device or a wireless station, a desktop computer or a computing device, a mobile computing device (such as a laptop, a notebook or a portable computing device), a tablet computer and / or a combination of devices. As shown in the figure, the communication device 106 may include a group of components 300 configured to perform core functions. For example, the group of components may be implemented as a system on a chip (SOC), which may include parts for various purposes. Alternatively, the group of components 300 may be implemented as a separate component or a group of components for various purposes. This group of components 300 may be (e.g., communicatively; directly or indirectly) coupled to various other circuits of the communication device 106.

[0054] For example, the communication device 106 may include various types of memory (e.g., including NAND flash memory 310), input / output interfaces such as a connector I / F 320 (e.g., for connecting to a computer system; a docking station; a charging station; an input device such as a microphone, a camera, a keyboard; an output device such as a speaker; etc.), a display 360 that may be integrated with the communication device 106 or external to the communication device 106, and cellular communication circuits 330 such as for 5G NR, LTE, GSM, etc., and short-range to medium-range wireless communication circuits 329 (e.g., Bluetooth TM In some embodiments, the communication device 106 may include wired communication circuitry (not shown), such as, for example, a network interface card for Ethernet.

[0055] Cellular communication circuitry 330 may be (e.g., communicatively; directly or indirectly) coupled to one or more antennas, such as antennas 335 and 336 as shown. Short-range to medium-range wireless communication circuitry 329 may also be (e.g., communicatively; directly or indirectly) coupled to one or more antennas, such as antennas 337 and 338 as shown. Alternatively, short-range to medium-range wireless communication circuitry 329 may be (e.g., communicatively; directly or indirectly) coupled to antennas 335 and 336 in addition to or in lieu of being (e.g., communicatively; directly or indirectly) coupled to antennas 337 and 338. Short-range to medium-range wireless communication circuitry 329 and / or cellular communication circuitry 330 may include multiple receive chains and / or multiple transmit chains for receiving and / or transmitting multiple spatial streams, such as in a multiple-input-multiple-output (MIMO) configuration.

[0056] In some embodiments, as further described below, the cellular communication circuit system 330 may include dedicated receive chains for multiple RATs (e.g., a first receive chain for LTE and a second receive chain for 5G NR). Such receive chains may include and / or be communicatively coupled (e.g., directly or indirectly) to a dedicated processor and / or radio. In addition, in some embodiments, the cellular communication circuit system 330 may include a single transmit chain that can switch between radio components dedicated to specific RATs. For example, a first radio component may be dedicated to a first RAT, such as LTE, and may communicate with a dedicated receive chain and a transmit chain shared with an additional radio component, such as a second radio component that may be dedicated to a second RAT (e.g., 5G NR) and may communicate with the dedicated receive chain and the shared transmit chain.

[0057] The communication device 106 may also include and / or be configured for use with one or more user interface elements. The user interface elements may include various elements such as a display 360 (which may be a touch screen display), a keyboard (which may be a separate keyboard or may be implemented as part of a touch screen display), a mouse, a microphone and / or speakers, one or more cameras, one or more buttons, and / or any of a variety of other elements capable of providing information to a user and / or receiving or interpreting user input.

[0058] The communication device 106 may also include one or more smart cards 345 having SIM (Subscriber Identity Module) functionality, such as one or more UICC cards (one or more Universal Integrated Circuit Cards) 345 .

[0059] As shown, the SOC 300 may include a processor 302 that may execute program instructions for the communication device 106 and a display circuit 304 that may perform graphics processing and provide display signals to a display 360. The processor 302 may also be coupled to a memory management unit (MMU) 340 (which may be configured to receive addresses from the processor 302 and convert those addresses to locations in a memory (e.g., a memory 306, a read-only memory (ROM) 350, a NAND flash memory 310)) and / or to other circuits or devices (such as the display circuit 304, the short-range wireless communication circuit 229, the cellular communication circuit 330, the connector I / F 320, and / or the display 360). The MMU 340 may be configured to perform memory protection and page table translation or setup. In some embodiments, the MMU 340 may be included as part of the processor 302.

[0060] As described above, the communication device 106 may be configured to communicate using wireless and / or wired communication circuits. The communication device 106 may be configured to transmit a request to attach to a first network node operating according to a first RAT and to transmit an indication that the wireless device is capable of maintaining a substantially concurrent connection with the first network node and a second network node operating according to a second RAT. The wireless device may also be configured to transmit a request to attach to a second network node. The request may include an indication that the wireless device is capable of maintaining a substantially concurrent connection with the first and second network nodes. In addition, the wireless device may be configured to receive an indication that a dual connection (DC) has been established with the first and second network nodes.

[0061] As described herein, the communication device 106 may include hardware and software components for implementing features of using multiplexing to perform transmissions according to multiple radio access technologies in the same frequency carrier (e.g., and / or multi-frequency carriers) and various other technologies described herein. The processor 302 of the communication device 106 may be configured to implement some or all of the features described in the present invention, for example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). Alternatively (or in addition), the processor 302 may be configured as a programmable hardware element, such as an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit). Alternatively (or in addition), in combination with one or more of the other components 300, 304, 306, 310, 320, 329, 330, 340, 345, 350, 360, the processor 302 of the communication device 106 may be configured to implement some or all of the features described in the present invention.

[0062] In addition, as described in the present invention, processor 302 may include one or more processing elements. Therefore, processor 302 may include one or more integrated circuits (ICs) configured to perform the functions of processor 302. In addition, each integrated circuit may include circuits (e.g., first circuits, second circuits, etc.) configured to perform the functions of one or more processors 302.

[0063] In addition, as described in the present invention, the cellular communication circuit 330 and the short-range wireless communication circuit 329 may each include one or more processing elements and / or processors. In other words, one or more processing elements / processors may be included in the cellular communication circuit 330, and similarly, one or more processing elements / processors may be included in the short-range wireless communication circuit 329. Therefore, the cellular communication circuit 330 may include one or more integrated circuits (ICs) configured to perform the functions of the cellular communication circuit 330. In addition, each integrated circuit may include a circuit (e.g., a first circuit, a second circuit, etc.) configured to perform the functions of the cellular communication circuit 330. Similarly, the short-range wireless communication circuit 329 may include one or more ICs configured to perform the functions of the short-range wireless communication circuit 329. In addition, each integrated circuit may include a circuit (e.g., a first circuit, a second circuit, etc.) configured to perform the functions of the short-range wireless communication circuit 329.

[0064] Figure 4 —Block diagram of a base station

[0065] Figure 4 An exemplary block diagram of a base station 102 according to some embodiments is shown. Note that Figure 4 The base station of is only one example of a possible base station. As shown, the base station 102 may include a processor 404 that may execute program instructions for the base station 102. The processor 404 may also be coupled to a memory management unit (MMU) 440 or other circuit or device, which may be configured to receive addresses from the processor 404 and convert these addresses to locations in memory (e.g., memory 460 and read-only memory (ROM) 450).

[0066] Base station 102 may include at least one network port 470. Network port 470 may be configured to couple to a telephone network and provide access to the telephone network described above. Figure 1 and Figure 2 Multiple devices of the telephone network described in, such as UE device 106.

[0067] The network port 470 (or an additional network port) may also or alternatively be configured to couple to a cellular network, such as a core network of a cellular service provider. The core network may provide mobility-related services and / or other services to multiple devices, such as the UE device 106. In some cases, the network port 470 may be coupled to a telephone network via the core network, and / or the core network may provide a telephone network (e.g., in other UE devices served by the cellular service provider).

[0068] In some embodiments, base station 102 may be a next generation base station, such as a 5G New Radio (5G NR) base station, or "gNB". In such embodiments, base station 102 may be connected to a legacy evolved packet core (EPC) network and / or to an NR core (NRC) network. Furthermore, base station 102 may be considered a 5G NR cell and may include one or more transition and reception points (TRPs). Furthermore, a UE capable of operating in accordance with 5G NR may be connected to one or more TRPs within one or more gNBs.

[0069] The base station 102 may include at least one antenna 434 and possibly multiple antennas. The radio component 430 and the at least one antenna 434 may be configured to function as a wireless transceiver and may be further configured to communicate with the UE device 106. The antenna 434 may communicate with the radio component 430 via a communication chain 432. The communication chain 432 may be a receive chain, a transmit chain, or both. The radio component 430 may be configured to communicate via various wireless communication standards, including but not limited to 5G NR, LTE, LTE-A, GSM, UMTS, CDMA2000, Wi-Fi, etc.

[0070] Base station 102 may be configured to perform wireless communications using multiple wireless communication standards. In some cases, base station 102 may include multiple radios that enable base station 102 to communicate according to multiple wireless communication technologies. For example, as one possibility, base station 102 may include an LTE radio component for performing communications according to LTE and a 5G NR radio component for performing communications according to 5GNR. In this case, base station 102 may be able to operate as both an LTE base station and a 5G NR base station. As another possibility, base station 102 may include a multimode radio component capable of performing communications according to any one of multiple wireless communication technologies (e.g., 5GNR and Wi-Fi, LTE and Wi-Fi, LTE and UMTS, LTE and CDMA2000, UMTS and GSM, etc.).

[0071] As further described later herein, the base station 102 may include hardware and software components for implementing or supporting the implementation of the features described herein. The processor 404 of the base station 102 may be configured to implement or support a portion or all of the implementation of the methods described herein, for example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). Alternatively, the processor 404 may be configured as a programmable hardware element such as an FPGA (field programmable gate array), or as an ASIC (application-specific integrated circuit) or a combination thereof. Alternatively (or in addition thereto), in combination with one or more of the other components 430, 432, 434, 440, 450, 460, 470, the processor 404 of the base station 102 may be configured to implement or support a portion or all of the implementation of the features described herein.

[0072] In addition, as described herein, the one or more processors 404 may include one or more processing elements. Thus, the processor 404 may include one or more integrated circuits (ICs) configured to perform the functions of the processor 404. In addition, each integrated circuit may include circuits (e.g., first circuits, second circuits, etc.) configured to perform the functions of the one or more processors 404.

[0073] In addition, as described herein, radio 430 may include one or more processing elements. Thus, radio 430 may include one or more integrated circuits (ICs) configured to perform the functions of radio 430. In addition, each integrated circuit may include a circuit (e.g., a first circuit, a second circuit, etc.) configured to perform the functions of radio 430.

[0074] Figure 5 —Block diagram of cellular communication circuit

[0075] Figure 5 An exemplary simplified block diagram of a cellular communication circuit according to some embodiments is shown. Note that Figure 5 The block diagram of the cellular communication circuitry of is only one example of possible cellular communication circuitry; other circuitry, such as circuitry that includes or is coupled to sufficient antennas for different RATs to perform uplink activities using separate antennas, is also possible. According to an embodiment, the cellular communication circuitry 330 may be included in a communication device such as the communication device 106 described above. As described above, the communication device 106 may be a user equipment (UE) device, a mobile device or mobile station, a wireless device or wireless station, a desktop computer or computing device, a mobile computing device (e.g., a laptop, notebook, or portable computing device), a tablet computer, and / or a combination of devices, among other devices.

[0076] Cellular communication circuitry 330 may be (eg, communicatively; directly or indirectly) coupled to one or more antennas, such as ( Figure 3 335a-335b and 336 are shown in FIG. 330 . In some embodiments, the cellular communication circuit 330 may include dedicated receive chains for multiple RATs (e.g., a first receive chain for LTE and a second receive chain for 5G NR). Such receive chains may include and / or be communicatively coupled (e.g., directly or indirectly) to a dedicated processor and / or radio. For example, Figure 5 As shown, cellular communication circuitry 330 may include modem 510 and modem 520. Modem 510 may be configured for communication according to a first RAT, such as, for example, LTE or LTE-A, and modem 520 may be configured for communication according to a second RAT, such as, for example, 5G NR.

[0077] As shown, the modem 510 may include one or more processors 512 and a memory 516 in communication with the processor 512. The modem 510 may communicate with a radio frequency (RF) front end 530. The RF front end 530 may include circuits for transmitting and receiving radio signals. For example, the RF front end 530 may include a receiving circuit (RX) 532 and a transmitting circuit (TX) 534. In some embodiments, the receiving circuit 532 may communicate with a downlink (DL) front end 550, which may include circuits for receiving radio signals via an antenna 335a.

[0078] Similarly, the modem 520 may include one or more processors 522 and a memory 526 in communication with the processor 522. The modem 520 may communicate with the RF front end 540. The RF front end 540 may include circuits for transmitting and receiving radio signals. For example, the RF front end 540 may include a receiving circuit 542 and a transmitting circuit 544. In some embodiments, the receiving circuit 542 may communicate with the DL front end 560, which may include circuits for receiving radio signals via the antenna 335b.

[0079] In some embodiments, the switch 570 may couple the transmit circuit 534 to an uplink (UL) front end 572. In addition, the switch 570 may couple the transmit circuit 544 to the UL front end 572. The UL front end 572 may include circuitry for transmitting radio signals via the antenna 336. Thus, when the cellular communication circuit 330 receives an instruction to transmit according to a first RAT (e.g., via a transmit chain including the transmit circuit 534 and the UL front end 572) supported by the modem 510, the switch 570 may be switched to a first state that allows the modem 510 to transmit signals according to the first RAT (e.g., via a transmit chain including the transmit circuit 534 and the UL front end 572). Similarly, when the cellular communication circuit 330 receives an instruction to transmit according to a second RAT (e.g., via a transmit chain including the transmit circuit 544 and the UL front end 572) supported by the modem 520, the switch 570 may be switched to a second state that allows the modem 520 to transmit signals according to the second RAT (e.g., via a transmit chain including the transmit circuit 544 and the UL front end 572).

[0080] In some embodiments, the cellular communication circuit 330 may be configured to transmit a request to attach to a first network node operating according to a first RAT via the first modem when the switch is in the first state, and to transmit an indication that the wireless device is capable of maintaining a substantially concurrent connection with the first network node and a second network node operating according to a second RAT via the first modem when the switch is in the first state. The wireless device may also be configured to transmit a request to attach to the second network node via the second radio component when the switch is in the second state. The request may include an indication that the wireless device is capable of maintaining a substantially concurrent connection with the first and second network nodes. In addition, the wireless device may be configured to receive an indication that a dual connection with the first and second network nodes has been established via the first radio component.

[0081] As described herein, the modem 510 may include hardware and software components for implementing features of using multiplexing to perform transmissions according to multiple radio access technologies in the same frequency carrier and various other technologies described herein. The processor 512 may be configured to implement part or all of the features described herein, for example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). Alternatively (or in addition), the processor 512 may be configured as a programmable hardware element such as an FPGA (field programmable gate array), or as an ASIC (application-specific integrated circuit). Alternatively (or in addition), in combination with one or more of the other components 530, 532, 534, 550, 570, 572, 335, and 336, the processor 512 may be configured to implement part or all of the feature parts described herein.

[0082] In some embodiments, processors 512, 522, etc. may be configured to implement or support a specific implementation of part or all of the methods described herein, for example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). Alternatively, processors 512, 522, etc. may be configured as programmable hardware elements such as field programmable gate arrays or as application-specific integrated circuits or a combination thereof. In addition, as described in the present invention, processors 512, 522, etc. may include one or more processing elements. Therefore, processors 512, 522, etc. may include one or more integrated circuits (ICs) configured to perform the functions of processors 512, 522, etc. In addition, each integrated circuit may include a circuit (e.g., a first circuit, a second circuit, etc.) configured to perform the functions of processors 512, 522, etc.

[0083] As described herein, the modem 520 may include hardware and software components for implementing the use of multiplexing to perform transmissions according to multiple radio access technologies in the same frequency carrier and various other technologies described herein. For example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium), the processor 522 may be configured to implement part or all of the feature parts described herein. Alternatively (or in addition), the processor 522 may be configured as a programmable hardware element such as an FPGA (field programmable gate array), or as an ASIC (application-specific integrated circuit). Alternatively (or additionally), in combination with one or more of the other components 540, 542, 544, 550, 570, 572, 335, and 336, the processor 522 may be configured to implement part or all of the feature parts described herein.

[0084] Figure 6-Figure 7 —5G NR Architecture

[0085] In some implementations, fifth generation (5G) wireless communications will initially be deployed in parallel with other wireless communications standards (e.g., LTE). Figure 6 Detailed implementation of possible standalone (SA) of a Next Generation Core (NGC) network 606 and a 5G NR base station (e.g., gNB 604), dual connectivity between LTE and 5G New Radio (5G NR or NR), such as according to Figure 7 The exemplary non-standalone (NSA) architecture shown has been specified as part of the initial deployment of NR. Figure 7As shown, the evolved packet core (EPC) network 600 may continue to communicate with the current LTE base station (e.g., eNB 602). In addition, the eNB 602 may communicate with the 5G NR base station (e.g., gNB 604), and data may be transferred between the core network 600 and the gNB 604. In some cases, the gNB 604 may also have at least a user plane reference point with the EPC network 600. Thus, the EPC network 600 may be used (or reused), and the gNB 604 may serve as additional capacity for the user equipment, for example, to provide increased downlink throughput for the UE. In other words, LTE may be used for control plane signaling, and NR may be used for user plane signaling. Thus, LTE may be used to establish a connection with the network, and NR may be used for data services. It should be understood that many other non-independent architecture variants are possible.

[0086] Figure 8 -Sensing Applications

[0087] Figure 8 An exemplary (and simplified) wireless communication system is shown in which aspects of the present disclosure may be implemented. Note that Figure 8 The system is only one example of possible systems, and embodiments of the present disclosure may be implemented in any of a variety of systems as desired.

[0088] As shown, the exemplary wireless communication system includes a ("first") wireless device 103 communicating with another ("second") wireless device. The first wireless device 103 and the second wireless device 105 may communicate wirelessly using any of a variety of wireless communication techniques, including possibly ranging wireless communication techniques.

[0089] As one possibility, the first wireless device 103 and the second wireless device 105 can perform ranging or other sensing techniques using wireless local area network (WLAN) communication technology (e.g., communication based on IEEE 802.11 / Wi-Fi) and / or WLAN wireless communication-based technology. One or both of the wireless device 103 and the wireless device 105 can also communicate via one or more additional wireless communication protocols, such as Bluetooth (BT), Bluetooth Low Energy (BLE), Near Field Communication (NFC), GSM, UMTS (WCDMA, TDSCDMA), LTE, LTE-Advanced (LTE-A), NR, 3GPP2 CDMA2000 (e.g., 1xRTT, 1xEV-DO, HRPD, eHRPD), Wi-MAX, GPS, etc. The ranging (or other sensing techniques) described herein can be performed using WLAN or various other wireless technologies (including BT, BLE, NFC or cellular, etc.).

[0090] Wireless device 103 and wireless device 105 may be any of a variety of types of wireless devices. As one possibility, one or more of wireless devices 103 and / or 105 may be substantially portable wireless user equipment (UE) devices, such as a smartphone, a handheld device, a wearable device (e.g., a smart watch), a tablet, a motor vehicle, or virtually any type of wireless device. As another possibility, one or more of wireless device 103 and / or wireless device 105 may be substantially stationary devices, such as a set-top box, a media player (e.g., an audio or audio-visual device such as a television), a game console, a desktop computer, an appliance, a door, an access point, a base station, or any of a variety of other types of devices. For example, among various possibilities, wireless device 103 and wireless device 105 may be Figures 1 to 7 As shown in and relative to Figures 1 to 7 Any device described. Ranging (or other sensing techniques) may be point-to-point (P2P). For example, in various possibilities, P2P ranging may be performed between a TV and a smartphone or between two phones.

[0091] Each of the wireless device 103 and the wireless device 105 may include wireless communication circuitry configured to facilitate the performance of wireless communication, which may include various digital and / or analog radio frequency (RF) components, a processor configured to execute program instructions stored in a memory (among various possibilities, such as processors 302, 404, 512, 522, baseband processors, processors associated with communication circuitry, etc.), programmable hardware elements such as field programmable gate arrays (FPGAs), and / or any of various other components. The wireless device 103 and / or the wireless device 105 may use any or all of such components to perform any of the method embodiments described herein, or any portion of any of the method embodiments described herein. For example, the wireless device 103 and / or the wireless device 105 may include one or more processors or processing elements that may be configured to cause the wireless device to cause the device to utilize any or all of such components to perform any of the method embodiments described herein, or any portion of any of the method embodiments described herein.

[0092] Each of wireless device 103 and wireless device 105 may include one or more antennas for communicating using one or more wireless communication protocols. In some cases, one or more portions of a receive chain and / or transmit chain may be shared between multiple wireless communication standards; for example, a device may be configured to communicate using either Bluetooth or Wi-Fi using partially or fully shared wireless communication circuitry (e.g., using shared radio components or at least shared radio components). The shared communication circuitry may include or be coupled to a single antenna or multiple antennas (e.g., for multiple input and multiple output (MIMO)) to perform wireless communication. Alternatively, a device may include an independent transmit chain and / or receive chain (e.g., including independent antennas and other radio components) for each wireless communication protocol that is configured to communicate therewith. As another possibility, a device may include one or more radios or radio components shared between multiple wireless communication protocols, as well as one or more radios or radio components used exclusively by a single wireless communication protocol. For example, a device may include a shared radio for communicating using one or more of LTE, CDMA2000 1xRTT, GSM, and / or 5G NR, and separate radios for communicating using each of Wi-Fi and Bluetooth. Other configurations are also possible.

[0093] As mentioned above, it can be combined with Figure 1 The present disclosure may be implemented in a wireless communication system of the present disclosure. For example, wireless devices 103 and / or 105 may perform one or more ranging wireless communication techniques or features described later herein with respect to the figures. By utilizing such techniques (and / or other techniques described herein), wireless devices may (at least according to some embodiments) be able to implement secure ranging communications with improved performance relative to prior art. Wireless devices 103 and / or 105 may be referred to as STAs.

[0094] Wireless sensing technology can be used to determine the distance and / or direction from one device to another device. In other words, wireless sensing can be used to determine the relative positions of wireless devices (eg, wireless device 103 and wireless device 105).

[0095] For example, two wireless devices (wireless device 103 and wireless device 105) may participate in a ranging operation, whereby at least one of the wireless devices will be able to determine or estimate the journey (e.g., distance) between the two devices, for example, by measuring the amount of time it takes to send a message between the devices. For example, according to some embodiments, the Fine Timing Measurement (FTM) protocol specified in 802.11-2016 may provide a mechanism based on time of flight (ToF) to perform ranging between two 802.11 / Wi-Fi devices. In FTM, the journey may be determined as a function of several time instances (t1, t2, t3, and t4), where t1, t2, t3, and t4 correspond to the departure time and arrival time of a measurement frame sent between two devices (e.g., two STAs) in two directions (e.g., uplink and downlink or from a first device to a second device and vice versa). For example, t1 may be the departure time from the first device, t2 may be the arrival time at the second device, t3 may be the departure time from the second device, and t4 may be the arrival time at the first device. Thus, t3-t2 may correspond to the processing time of the second device, t2-t1 may correspond to the one-way travel time from the first device to the second device, and t4-t3 may be the one-way travel time from the second device to the first device. Thus, the round-trip flight time may be calculated as (t4-t1)-(t3-t2), in other words, the total time minus the processing time. Standards under development (e.g., 802.11az) may be intended to improve and / or optimize ranging protocols for various use cases, including very high throughput (VHT), high efficiency (HE), and / or 60 GHz (e.g., millimeter wave or mmWave) communications, among others. In addition, improvements in scalability and security may be desired.

[0096] In some embodiments, a ranging protocol (e.g., within 802.11az) may include a public negotiation phase that may precede a measurement phase for various ranging modes and / or packet sequences (e.g., FTM, high efficiency ranging for 802.11az (HEz), or VHT ranging for 802.11az (VHTz); it should be noted that these may be working names for various ranging modes, these names may change, and other ranging modes may be used). During the negotiation phase, an initiating STA (iSTA) may send an initial measurement request frame (e.g., an FTM measurement request frame, such as a negotiation frame). The measurement request frame may include a set of ranging parameters. For example, the measurement request frame may include scheduling parameters in one or more FTM parameter elements or a set of trip measurement parameter elements in a next generation positioning (NGP) parameter element, etc. The ranging parameters may describe bandwidths available for ranging, bandwidths measured by the iSTA, radio frequency (RF) related parameters, one or more ranging modes supported by the iSTA, and / or ranging security requirements, etc. The frame content may describe the capabilities and availability of the iSTA for ranging measurement exchanges. Among various possibilities, this frame may describe whether the iSTA supports secure ToF (SToF) measurements. SToF may be a new sensor feature for measuring the distance between two devices in a secure manner. The SToF feature may be related to the 802.11az standard still under development by the IEEE.

[0097] The responding STA (rSTA) may indicate various ranging parameters in response to the initial measurement request frame from the iSTA. For example, the rSTA may indicate whether it supports SToF. The rSTA may send an acknowledgment (ACK) to the measurement request frame. The rSTA may also send a response frame (e.g., a first FTM measurement frame). In some embodiments, the measurement frame may be sent within a few milliseconds (e.g., 10 ms) of receiving the initial measurement request frame. Note that other response times or time delays are possible (e.g., 5 ms, 15 ms, tens of milliseconds, hundreds of milliseconds, etc.).

[0098] Sensing applications for determining a direction from one device to another device can operate in a similar manner. For example, a first device can transmit a series of measurement frames over time, for example, transmitting frames in different directions at different times. A responding second device can respond to one or more of the measurement frames, for example, indicating which measurement frame was received with the best strength (or other measurement). Thus, the first device and / or the second device can determine the direction based on which of the measurement frames was received by the receiving device with the best measurement.

[0099] Fig. 9 and Fig.10 – Real-time analog front end (AFE) response estimation for sensing applications

[0100] Estimating the channel can be an important aspect of sensing applications. For example, accurate channel estimation can be useful for accurately and / or precisely determining the time of arrival of a known sequence (e.g., a training sequence) at a receiving wireless device. The time of arrival can be used to estimate the travel or distance between two devices. In some systems, especially for wideband channels, the channel response of the analog front end (AFE) of the receiving wireless device can be a significant source of error for channel estimation and sensing applications. The AFE may refer to a circuit between one or more antennas and one or more analog-to-digital converters (ADCs) or modems. One or more antennas may be considered as components of the AFE. For example, the AFE may include any number of antennas, amplifiers, phase shifters, bandpass filters, low-pass filters, mixers, trackers, etc. For example, the AFE may be a component or subset of the short-range wireless communication circuit 329 and / or the cellular communication circuit 330. Similarly, the AFE may be or include one or more chips configured to convert between a radio frequency (RF) signal and an intermediate frequency (IF) signal and / or a baseband (BB) signal.

[0101] The AFE response may vary significantly at different frequencies (e.g., the response may not be flat over the bandwidth of the channel, particularly for channels with larger bandwidths). Thus, according to some embodiments, the AFE response may be a significant source of error in channel estimation and sensing applications. The AFE response may be a larger source of error for channels with larger bandwidths. For example, the AFE response may vary over the bandwidth of channels for various wireless technologies, including: 802.11ad / ay with 2 GHz to 4 GHz channels, ultra-wideband (UWB) communications with 0.5 GHz to 1 GHz channels, and 802.11ac / ax with 80 MHz to 160 MHz channels, among other possibilities.

[0102] In some embodiments, the AFE response may be corrected by using a loopback technique. Generally speaking, such a loopback may be included in a system with a small number of antennas (e.g., approximately up to 3) and in which a transmit (Tx) chain and a receive (Rx) chain may be connected. However, in other embodiments, loopbacks may be impractical or may be undesirable in view of other design features of the wireless device. For example, loopbacks of a large number of antennas that may share some circuits (e.g., cables, etc.) may prevent or block loopbacks. In other words, some AFE circuits may not be configured for loopbacks.

[0103] For example, because the modem estimates the overall channel response including the physical channel and the AFE response, the effect of the gain flatness of the side RF channel may have a small effect on the modem performance. In other words, the modem can equalize the overall response.

[0104] However, in sensing applications such as ranging (e.g., time of flight (ToF)), it may be beneficial to de-embed the AFE response in order to estimate only the channel response of the physical channel. In other words, improved ToF accuracy may be achieved by isolating the channel response of the physical channel from the response of the AFE. For example, in non-line-of-sight (NLOS) measurements, the actual channel response of some AFEs may result in a ToF error of about 2ns relative to a completely flat AFE response. In the context of some systems, such errors may be very large, which may require, for example, ToF to be accurate with a tolerance on the order of tens of picoseconds (ps).

[0105] Therefore, improved methods for channel estimation may be needed. Fig. 9 An exemplary technique for performing channel estimation with compensation for the AFE response is shown. Fig. 9 Aspects of the method may be implemented by a wireless device (e.g., wireless devices 103 and 105 shown in the various figures and described with respect to the various figures), or more generally, as required, in combination with any of the computer systems or devices shown in the figures and other circuits, systems, devices, elements or components and other devices shown in the figures. For example, one or more processors (or processing elements) of the UE (in various possibilities, for example, processors 302, 404, 512, 522, baseband processors, processors associated with communication circuits, etc.) may cause the wireless device to perform some or all of the method elements shown. It should be noted that although at least some elements of the method are described in a manner involving the use of communication technologies and / or features associated with 802.11 specification documents, such description is not intended to limit the present disclosure, and aspects of the method may be used in any suitable wireless communication system as required. In various embodiments, some of the method elements shown may be performed simultaneously in an order different from the order shown, may be replaced by other method elements, or may be omitted. Additional method elements may also be performed as required. As shown, the method may operate as follows.

[0106] According to some embodiments, a wireless device 103 (eg, any type of wireless device) may begin a sensing process (902) with a second wireless device 105 (eg, any type of wireless device).

[0107] The sensing process may be a distance or ranging measurement process, for example using ToF. In some embodiments, the sensing process may be an angle / direction estimation, for example using angle of arrival.

[0108] Any of these devices may initiate the sensing process. For example, the wireless device 103 may be an initiating device (iSTA) or a responding device (rSTA).

[0109] The devices may negotiate various ranging parameters (e.g., time and frequency resources for ranging). The devices may indicate that they support secure ToF (SToF) ranging, and may negotiate the use of SToF. Such negotiation and indication may be performed by including various parameters or indicators in fields of one or more initial messages, such as a fine timing measurement (FTM) measurement request frame and / or other negotiation frames, among other possibilities.

[0110] The devices may negotiate a channel estimation sequence (eg, a known sequence, a training sequence) for use in the sensing process. For example, device 103 and device 105 may determine a key for generating a known sequence.

[0111] In some embodiments, the wireless device 103 and the wireless device 105 may negotiate the use of data-assisted channel estimation for the sensing process. In other words, instead of or in addition to the channel estimation sequence, the wireless devices 103 and 105 may agree to use other data (e.g., application data) for channel estimation and / or sensing.

[0112] The wireless device 103 and the wireless device 105 may negotiate the structure of the sensing process signal. For example, the wireless device 103 and the wireless device 105 may negotiate a plurality of channel estimation sequences, information (e.g., a key) used to generate these sequences, and possibly the amount of data used for the channel estimation and sensing process. A larger number of sequences may provide increased processing gain. In other words, the processing gain may be proportional to the number of sequences used to estimate the channel and / or perform sensing (e.g., ToF) measurements. Therefore, a larger number of sequences may be used to achieve more accurate channel estimates and more accurate sensing estimates.

[0113] The negotiation may be performed using WLAN and / or another RAT (eg, BT, BLE, cellular, NFC, etc.), as desired.

[0114] According to some embodiments, the wireless device 103 may receive a sensing process signal (904) transmitted by the wireless device 105. The signal may include one or more channel estimation sequences and / or other data configured for channel estimation. The signal may be received via a wireless channel, for example, using one or more antennas coupled to the AFE. The channel estimation sequence may include a known sequence, for example, as negotiated in 902. In some embodiments, application data may also be received. The sensing process signal may be a WLAN transmission and / or may be a transmission according to another RAT (e.g., BT, BLE, cellular, NFC, etc.), as desired.

[0115] Among various possibilities, the sensing process signal may be or include a ranging process signal and / or an angle estimation process signal.

[0116] According to some embodiments, based on the received signal, the wireless device 103 may estimate an overall channel response (eg, including the physical channel and the AFE response) (906).

[0117] refer to Fig.10 , shows an exemplary receiver for estimating channel response, the overall channel response 1008 may include: physical (e.g., wireless, cascaded) channel response 1002, thermal noise 1010, and front-end gain (e.g., AFE response) 1004. In other words, the overall channel response may include points AD, such as Fig.10 1006. Point A represents the initially transmitted signal. Point B represents the signal after the wireless channel 1002. Point C shows the signal after adding thermal noise (e.g., additive white Gaussian noise (AWGN)) 1010. Point D represents the signal after the AFE response 1004, such as the signal received by the modem 1006. In various possibilities, the overall channel response can be estimated by the modem 1006.

[0118] According to some embodiments, Formula 1 shows that, for example, Fig.10 Mathematical representation of the signal received by the wireless device 103 at point D in FIG.

[0119] y n =(h·s n +v n )·g=h·s n ·g+v n ·g

[0120] Formula 1

[0121] Item n represents the received signal for a single channel subcarrier at time or symbol n (eg, the nth symbol of the received signal for the channel estimation sequence). In other words, y n represents the signal or symbol received by modem 1006 at time or symbol n. Term h represents the channel response (eg, of wireless channel 1002). Term s n represents the known or expected signal at time n. Note that s n can be equal to any non-zero complex number. The term v n represents the thermal noise (e.g., AWGN) 1010 at time n. Note that AWGN averages to zero, so the standard deviation represented by σ can be used in the subsequent formulas. The term g represents the complex value of the AFE response 1004. Therefore, as shown, the AFE can independently affect the estimate of the received signal relative to the channel and noise.

[0122] See again Fig. 9, to determine the overall channel response, the wireless device 103 may compare the received sequence to a known or expected channel estimate sequence. The entire channel (e.g., A to D, e.g., concatenation hg) may be estimated according to Equation 2, e.g., by comparing the received signal to the corresponding known or expected signal over a period of time (e.g., over a number of symbols). As shown, according to some embodiments, the concatenation of the channel response h and the AFE response g may be equal to y averaged over N symbols (e.g., or N time units). n With s n ratio.

[0123]

[0124] Formula 2

[0125] In some implementations, the received application data may also be used to estimate the overall channel response. In other words, the wireless device 103 may use the received application data to perform data-aided channel estimation.

[0126] See again Fig. 9 According to some embodiments, the wireless device 103 may estimate the thermal noise characteristics of the channel (908). For example, the wireless device 103 may estimate the standard deviation or variance (e.g., the square of the standard deviation) of the noise. Fig.10 , it should be noted that thermal noise 1010 may not pass through the entire channel (e.g., AD). In contrast, thermal noise only passes through the AFE, such as (CD). The wireless device 103 may perform an estimation of the variance of the noise based on the received sequence and / or other received data.

[0127] The wireless device 103 may estimate the frequency spectrum of the noise variance. For example, the wireless device may determine the variance level of the noise as a function of frequency.

[0128] In some embodiments, the modem 1006 may routinely (e.g., periodically, iteratively, or continuously) estimate the variance of the noise. For example, the modem may estimate the variance of the noise using continuous or periodic measurements. For example, the modem may estimate the variance of the noise in order to determine various metrics, such as a signal-to-noise ratio (SNR), etc. Thus, determining the variance of the noise may be based on a maximum current estimate of a conventional noise estimate. For example, a recent rolling average or similar value may be used at a particular time associated with the channel estimate (e.g., at approximately the time of the sensing process signal).

[0129] In some embodiments, the modem 1006 may generate an estimate of the noise used for the sensing process. For example, in order to perform channel estimation and accurate sensing (eg, ToF) measurements, a variance estimate of the noise may be determined (eg, using potentially customized estimation features or techniques).

[0130] According to some embodiments, the wireless device 103 may estimate the AFE response (910). For example, the wireless device 103 may estimate the absolute value of the AFE gain response, which may include the response of one or more antennas and other circuits, such as amplifiers (e.g., low noise amplifiers, etc.), mixers, trackers, filters (e.g., low pass filters, band pass filters, high pass filters, etc.). Note that any or all of these exemplary components may or may not be included in the AFE. Additional or different components may be included. In other words, the wireless device 103 may estimate the impact on the signal of the AFE gain 1004, for example, the difference in the signal at point D relative to point C.

[0131] In some embodiments, the absolute value of the AFE gain (e.g., by noise amplification, e.g., comparison Fig.10 Points B and D) can be estimated as shown in Formulas 3 and 4.

[0132]

[0133] Formula 3

[0134] As shown in Equation 3, the noise variance (e.g., σ 2 ) and the absolute value of the AFE gain (e.g., g 2 ) can be equal to y n With s n = The average of the squares of the ratio of σ minus the concatenation of the estimated channel response and the AFE response. Note that the denominator shown (e.g., N-1) is exemplary only, and other denominators may be used, e.g., consistent with statistical theory and design for unbiased estimates of standard deviation and variance. Thus, the absolute value of the AFE gain can be obtained by dividing the above values ​​(e.g., σ by 2 and g 2 The concatenation of the estimated channel response and the AFE response may be subtracted from the received samples, normalized by the corresponding known symbols or known samples. In other words, Equation 3 may be solved for the absolute value of the AFE response (the absolute value of g).

[0135]

[0136] Formula 4

[0137] Equation 4 shows the solution to Equation 3 according to some embodiments.

[0138] In some embodiments, the wireless device 103 may estimate the AFE response routinely (e.g., periodically, iteratively, or continuously). For example, the wireless device 103 may estimate the AFE using continuous or periodic measurements of noise. Thus, determining the AFE may be based on the most current estimate of the conventional noise estimate. For example, the current or latest AFE may be estimated using a recent rolling average or similar value of the noise at a particular time associated with the channel estimate (e.g., at about the time the process signal is sensed).

[0139] In some embodiments, the wireless device 103 may generate an estimate of the AFE of the sensing process. For example, the estimate of the AFE may be determined for the purpose of performing channel estimation and accurate sensing (e.g., ToF) measurements. Such an AFE estimate may be based on a noise estimate associated with the time of the sensing process signal.

[0140] See again Fig. 9 According to some embodiments, the wireless device 103 may estimate the channel response of the AFE (912). In other words, the wireless device 103 may determine an approximate channel response in addition to the response of the AFE (eg, the channel response before the AFE). Fig.10 For example, the wireless device 103 may determine a channel response of the wireless channel 1002, e.g., the difference between point A and point B. For example, the wireless device 103 may subtract the estimated response of the AFE in 910 from the estimated response of the entire channel in 906. Thus, the wireless device 103 may determine a channel estimate that compensates (e.g., corrects) the estimated AFE response.

[0141] In other words, the wireless device 103 may use correction of the AFE response to equalize the channel response over the channel bandwidth (e.g., which may be 2 GHz-4 GHz and may include many (e.g., hundreds, in various possibilities) subcarriers). For example, in various possibilities, such equalization may result in a significant reduction in ripple, e.g., nearly a five-fold reduction in ripple.

[0142] In some embodiments, the wireless device 103 may use a larger number of channel estimation sequences (and / or other data) in order to achieve a desired level of processing gain. For example, if a more accurate channel estimate is desired, the wireless device 103 may use a larger number of sequences for time domain and / or frequency domain averaging. In other words, for the purpose of channel estimation, the wireless device 103 may perform a coherent summation of the number of sequences in order to estimate the channel with the desired accuracy. It should be understood that the desired number of sequences (and / or other data) may be used to estimate the overall channel, noise, AFE response, and / or channel response network of the AFE. The wireless device 103 may select multiple channel estimation sequences (and / or amounts of other data) in order to achieve a desired level of reduction in ripple (e.g., or more generally, improvement in channel estimation).

[0143] According to some embodiments, the wireless device 103 may perform a sensing measurement (914). For example, in various possibilities, the wireless device 103 may use a channel estimate (excluding the AFE channel response) to determine the ToF and the corresponding distance to the wireless device 105. In other words, the wireless device 103 may compensate the overall channel estimate based on the estimate of the AFE response to perform the sensing measurement with improved accuracy (e.g., relative to sensing measurements that do not compensate for the AFE). For example, based on the compensated channel estimate, the wireless device 103 may determine the time of arrival of the sensing process signal. The wireless device 103 may use the time of arrival of the sensing process signal to determine the ToF of the sensing process signal and the range / distance to the wireless device 105.

[0144] Fig.11 –ToF measurement

[0145] Fig.11 is a communication flow chart showing ToF according to some embodiments. Two devices (device A and device B, which may correspond to wireless devices 103 and 105) may exchange any number of messages at time t0 to negotiate the ToF process. For example, one of the devices, such as an initiating STA (e.g., device B), may send an initial measurement request to another device (e.g., a responding STA, such as device A). The initial measurement request may be or include an initial FTM request. The second device may respond (e.g., with an ACK). In the measurement request and response, the devices may negotiate various parameters of ToF, including agreeing on a pre-coordinated seed for generating a known sequence. It should be understood that although the negotiation phase is illustrated at a single time t0, multiple messages may be included and the negotiation may take any amount of time.

[0146] At a second time t1 , device A may transmit to device B a measurement signal (eg, FTM frames) that may include any number of known sequences.

[0147] At a third time t2, device B may receive the measurement signal. Device B may perform channel estimation (e.g., using a combined channel estimation of the plurality of known sequences and the plurality of corresponding received sequences from the measurement signal). At the first significant peak of the channel estimate, device B may determine a time interval dt, e.g., a one-way ToF between the transmission of the known sequence by device A and the reception of the corresponding received sequence by device B. Device B may calculate the trip based on the time interval.

[0148] At a fourth time t3, device B may transmit a second measurement signal (eg, FTM frame) that may include any number of known sequences to device A. The known sequence of the second measurement signal may be different from the known sequence of the first measurement signal.

[0149] At a fifth time t4, device A may receive a second measurement signal. Device A may perform channel estimation (e.g., using a second combined channel estimate of the plurality of known sequences and the plurality of corresponding received sequences from the second measurement signal). At a first significant peak in the second channel estimate, device A may determine a time interval, e.g., a one-way ToF between device B transmitting the known sequence and device A receiving the corresponding received sequence. Device A may also determine a round-trip ToF based on the time between t1 and t4 (e.g., the first significant peak in the second channel estimate). Device A may calculate a trip based on the one-way and / or round-trip time intervals.

[0150] It should be understood that determining the range / distance between devices A and B is different from determining the communication range of either device. For example, if one of device A and device B has a communication range of a first distance (e.g., x meters), the range / distance between the two devices may be a different second distance (e.g., y meters). ToF measurements can be used to determine the distance between the two devices (e.g., y meters).

[0151] Additional information and examples

[0152] In some embodiments, the Fig. 9 The technology enables improved channel estimation, thereby achieving improved sensing measurements. The following discussion provides further information about some embodiments.

[0153] See also Fig.10, a signal (e.g., a sensing process signal) may pass through a cascaded channel (e.g., a wireless channel) and an AFE (e.g., from A to D). However, noise may only pass through the AFE (e.g., from C to D). Therefore, the wireless device 103 may perform a two-stage channel estimation. In a first stage, the wireless device 103 may estimate the cascade of the channel and the AFE (e.g., from A to D). The estimation may be performed by a training sequence and / or data included in the sensing signal. In a second stage, the wireless device 103 may infer the AFE gain response (e.g., from B to D) by estimating the noise spectrum, for example, because the AFE may color the noise. The wireless device 103 may use the AFE gain response to determine an improved channel estimate corrected for the AFE gain response. The wireless device 103 may use time domain averaging or frequency domain averaging to achieve a desired level of processing gain. The improved channel estimate may be used for sensing measurements, for example, to estimate the time of arrival of a signal and thus estimate ToF.

[0154] In some embodiments, the wireless device 103 may determine the spectral composition of the noise detected by the modem 1006 or the like. The noise may not be entirely AWGN, for example, it may have some non-random characteristics, such as different spectral compositions. The difference between the noise detected by the modem 1006 and pure AWGN may be attributed to the AFE response. Therefore, the wireless device 103 may use the difference between the detected noise and pure AWGN to calculate the AFE response. The calculated AFE response may be used to correct the overall channel estimate to compensate for the AFE response. The corrected channel estimate may then be used to determine ToF or other sensing measurements.

[0155] For example, consider a noise variance estimate that includes a higher variance at higher frequencies in the channel bandwidth. Such an estimate of the noise variance may indicate that the AFE gain response is more significant in higher frequencies than in other frequencies in the channel bandwidth. Therefore, the wireless device 103 may estimate the absolute value of the AFE gain response to be relatively large at high frequencies and relatively small (or zero) at lower frequencies according to Formula 4, etc. Therefore, the overall channel estimate may be corrected by, for example, reducing the gain at higher frequencies relative to lower frequencies.

[0156] In some embodiments, the wireless device 103 may estimate the absolute value of g, for example, the AFE gain response prior to the ranging transaction. In other words, the wireless device 103 may estimate the noise characteristics (908) and estimate the AFE response (910) prior to receiving the sensing process signal (904) and possibly prior to negotiating the sensing process parameters with the second wireless device 105. During the ranging transaction, the wireless device 103 may estimate the overall channel (hg) (906). The wireless device 103 may divide the estimated channel (hg) by the absolute value of the AFE gain response (g) in the frequency domain. (Note that in some embodiments, time domain division may be used). In other words, the wireless device 103 may perform a de-embedding or de-convolution of the estimated absolute value of g from the estimate of hg. For example, Equation 4 may be used to estimate the absolute value of g, which may be substituted into Equation 2 to solve for the estimated channel (h) corrected for the AFE gain. The estimated channel (h) corrected for the AFE gain response (e.g., with g de-embedded) may be used to estimate ToF or for other sensing measurements.

[0157] The embodiments of the present disclosure may be implemented in any of a variety of forms. For example, some embodiments may be implemented as computer-implemented methods, computer-readable storage media, or computer systems. Other embodiments may be implemented using one or more custom-designed hardware devices such as ASICs. Other embodiments may be implemented using one or more programmable hardware elements such as FPGAs.

[0158] In some embodiments, a non-transitory computer-readable storage medium may be configured such that it stores program instructions and / or data, wherein if the program instructions are executed by a computer system, the computer system is caused to perform a method, such as any one of the method embodiments described herein, or any combination of the method embodiments described herein, or any subset of any method embodiments described herein, or any combination of such subsets.

[0159] In some embodiments, a device (e.g., a UE) may be configured to include a processor (or a group of processors) and a memory medium, wherein the memory medium stores program instructions, wherein the processor is configured to read and execute the program instructions from the memory medium, wherein the program instructions are executable to implement any of the various method implementations described herein (or any combination of the method implementations described herein, or any subset of any method implementations described herein, or any combination of such subsets). The device may be implemented in any of various forms.

[0160] It is understood that the use of personally identifiable information should be subject to privacy policies and practices that are generally recognized to meet or exceed industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of the authorized use should be clearly stated to users.

[0161] Although the above embodiments have been described in considerable detail, numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to encompass all such variations and modifications.

Claims

1. An apparatus for managing a first wireless device, The apparatus comprises a processor configured to cause the first wireless device to: starting a ranging process with a second wireless device; receiving a ranging process signal from the second wireless device through a channel; estimating noise characteristics on the channel; estimating an analog front end (AFE) response based on the noise characteristics; a channel estimation network for estimating the AFE response based on the AFE response and the ranging process signal; determining a time of flight based on the channel estimation network of the AFE response; as well as A distance between the first wireless device and the second wireless device is determined based on the flight time.

2. The device according to claim 1, in, The noise characteristics include a frequency spectrum of the noise.

3. The device according to claim 1, in, Initiating the ranging process includes negotiating a plurality of channel estimation sequences to be included in the ranging process signal.

4. The device according to claim 3, in, The plurality of channel estimation sequences are selected to provide a desired level of processing gain.

5. The device according to claim 1, in, The noise characteristic comprises a variance of the noise, wherein determining the AFE response comprises: estimating a concatenation of the variance of the noise and an absolute value of the AFE response; dividing the concatenation by the variance of the noise; and Take the square root of the result of the division.

6. The device according to claim 1, in, The apparatus is further configured to cause the first wireless device to periodically estimate the noise characteristic, wherein a most current estimate of the noise characteristic is used to estimate the AFE response.

7. The device according to claim 1, in, The ranging process signal is transmitted via a wireless local area network.

8. A first wireless device, comprising: at least one antenna, the at least one antenna being coupled to an analog front end (AFE); and a processor coupled to the AFE and configured to cause the first wireless device to: negotiating sensing parameters with the second wireless device; receiving, based on the sensed parameter, a signal including a plurality of training sequences from the second wireless device using the at least one antenna; Performing channel estimation based on the signal, the channel estimation comprising: estimating a channel including the AFE; inferring a gain response of the AFE by estimating noise characteristics; and determining a channel estimate corrected for the gain response of the AFE based on the channel including the AFE and the gain response of the AFE; and A time of arrival of the signal is determined based on the channel estimate.

9. The first wireless device according to claim 8, in, Inferring the gain response includes: The channel including the AFE is subtracted from received samples of the signal normalized by corresponding known samples.

10. The first wireless device according to claim 9, in, The results of the subtraction are averaged over the plurality of training sequences.

11. The first wireless device according to claim 8, in, Determining the channel estimate corrected for the gain response of the AFE includes equalizing the channel response over a bandwidth of the channel.

12. The first wireless device according to claim 11, in, The bandwidth of the channel is 2 GHz to 4 GHz.

13. The first wireless device according to claim 8, in, Performing the channel estimation further includes: A coherent summation of the plurality of training sequences is performed.

14. The first wireless device according to claim 8, in, The plurality of training sequences are selected to provide a desired level of improvement in the channel estimate.

15. The first wireless device according to claim 8, in, The AFE includes at least one of the following: filter; Phase shifter; or Amplifier.

16. The first wireless device according to claim 8, in, The AFE includes circuitry that is not configured for loopback.

17. A method for performing ranging measurements, the method comprising: At the first wireless device: negotiating ranging parameters with the second wireless device; receiving a ranging signal from the second wireless device according to the ranging parameter; determining an overall channel estimate based on the ranging signal; determining a spectral composition of noise detected at a modem of the first wireless device; determining a correction to the overall channel estimate based on the spectral composition, wherein the correction corresponds to a front-end gain of the first wireless device; determining a time of flight of the ranging signal based on the correction; and A trip from the first wireless device to the second wireless device is determined based on the flight time.

18. The method according to claim 17, in, The overall channel estimate is a data-aided channel estimate.

19. The method according to claim 17, in, The spectral composition of the noise is different from additive white Gaussian noise.

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