Method and apparatus for distinguishing human grip from protective cover for user device

Abstract

Methods and apparatus for distinguishing whether an antenna of a user equipment (UE) is blocked by a covering (e.g., a protective rubber or plastic housing) or by human tissue (e.g., fingers or palm). The transmission power of an uplink (UL) signal can be adjusted accordingly using a relatively higher transmission power for open spaces or coverings and a relatively lower transmission power for human tissues. One example method for wireless communication by a UE generally includes transmitting a first signal from the UE, receiving, at the UE, a plurality of signals based on the transmitted first signal, determining values of at least two different types of parameters based on the received plurality of signals, determining an environmental scenario of the UE based on the values of the at least two different types of parameters, and transmitting the environmental scenario to the UE. And transmitting the second signal using a transmission power based on the determined environmental scene.

Description

[0001] Description of the case

[0002] This application is a divisional application of the Chinese invention patent application with application number 202080042413.X filed on June 12, 2020 and entitled “Method and device for distinguishing between human grip and protective cover for user equipment”.

[0003] CROSS-REFERENCE TO RELATED APPLICATIONS

[0004] This application claims priority to U.S. Application No. 16 / 898,746, filed on June 11, 2020, which claims priority to and the benefit of U.S. Provisional Patent Application No. 62 / 860,608, filed on June 12, 2019, both of which are expressly incorporated herein in their entirety. Technical Field

[0005] Certain aspects of the present disclosure relate generally to wireless devices, and more particularly to distinguishing between a human grip and a protective cover on a wireless device. Background Art

[0006] Modern wireless devices, such as cellular phones, are generally required to meet radio frequency (RF) exposure limits established by national and international standards and regulations. To ensure compliance with the standards, such devices currently must undergo an extensive certification process before being marketed. In order to ensure that wireless devices comply with RF exposure limits, various technologies have been developed to enable wireless devices to assess RF exposure from the wireless device in real time and adjust the transmission power of the wireless device accordingly to comply with the RF exposure limits. Summary of the invention

[0007] The systems, methods, and devices of the present disclosure each have several aspects, no single aspect being solely responsible for its desirable attributes. Without limiting the scope of the present disclosure as expressed by the appended claims, some features will now be briefly discussed. After considering this discussion, and particularly after reading the section entitled "Detailed Description of the Invention," it will be possible to understand how the features of the present disclosure provide advantages including improved systems and methods for assessing RF exposure from wireless devices.

[0008] Certain aspects of the present disclosure provide a method for wireless communication by a user equipment (UE). The method generally includes transmitting a first signal from the UE, receiving multiple signals at the UE based on the transmitted first signal, determining values ​​of at least two different types of parameters based on the received multiple signals, determining an environmental scenario of the UE based on the values ​​of the at least two different types of parameters, and transmitting a second signal using a transmission power based on the determined environmental scenario.

[0009] Certain aspects of the present disclosure relate to an apparatus for wireless communication. The apparatus includes a transmitter, a receiver, and a processing system. The transmitter is configured to transmit a first signal from the apparatus, and the receiver is configured to receive a plurality of signals based on the transmitted first signal. The processing system is configured to determine values ​​of at least two different types of parameters based on the received plurality of signals, and to determine an environmental scenario of the apparatus based on the values ​​of the at least two different types of parameters. The transmitter is also configured to transmit a second signal using a transmission power based on the determined environmental scenario.

[0010] Certain aspects of the present disclosure relate to an apparatus for wireless communication. The apparatus generally includes means for transmitting a first signal, means for receiving a plurality of signals based on the transmitted first signal, means for determining values ​​of at least two different types of parameters based on the received plurality of signals, means for determining an environmental scenario of the apparatus based on the values ​​of the at least two different types of parameters, and means for transmitting a second signal using a transmission power based on the determined environmental scenario.

[0011] Certain aspects of the present disclosure relate to a non-transitory computer-readable medium having instructions that, when executed by a processing system, cause the processing system to perform operations for wireless communication by a UE. The operations generally include: controlling transmission of a first signal from the UE, controlling reception of multiple signals based on the transmitted first signal, determining values ​​of at least two different types of parameters based on the received multiple signals, determining an environmental scenario of the UE based on the values ​​of the at least two different types of parameters, and controlling transmission of a second signal using a transmission power based on the determined environmental scenario.

[0012] Certain aspects of the present disclosure provide a method for wireless communication by a UE. The method generally includes transmitting a first signal from the UE; receiving multiple signals at the UE based on the transmitted first signal; determining a value of each parameter in one or more parameters based on the received multiple signals; determining a type of coverage adjacent to an antenna array of the UE based on the value of each parameter in the one or more parameters; selecting an antenna array codebook based on the determined type of coverage; and transmitting a second signal based on the selected antenna array codebook.

[0013] Certain aspects of the present disclosure relate to an apparatus for wireless communication. The apparatus includes an antenna array, a transmitter, a receiver, and a processing system. The transmitter is coupled to the antenna array and is configured to transmit a first signal via the antenna array. The receiver is coupled to the antenna array and is configured to receive multiple signals via the antenna array based on the transmitted first signal. The processing system is coupled to the receiver and is configured to determine a value of each of one or more parameters based on the multiple signals received, determine a type of coverage adjacent to the antenna array of the apparatus based on the value of each of the one or more parameters, and select an antenna array codebook based on the determined type of coverage. The transmitter is also configured to transmit a second signal via the antenna array based on the selected antenna array codebook.

[0014] Certain aspects of the present disclosure relate to an apparatus for wireless communication. The apparatus generally includes a component for transmitting a first signal from the apparatus; a component for receiving multiple signals based on the transmitted first signal; a component for determining a value of each of one or more parameters based on the received multiple signals; a component for determining a type of coverage adjacent to an antenna array of the apparatus based on the value of each of the one or more parameters; a component for selecting an antenna array codebook based on the determined type of coverage; and a component for transmitting a second signal based on the selected antenna array codebook.

[0015] Certain aspects of the present disclosure relate to a non-transitory computer-readable medium having instructions that, when executed by a processing system, cause the processing system to perform operations for wireless communication by a UE. The operations generally include: controlling the transmission of a first signal from the UE; controlling the reception of multiple signals based on the transmitted first signal; determining a value for each of one or more parameters based on the received multiple signals; determining a type of coverage adjacent to an antenna array of the UE based on the value of each of the one or more parameters; selecting an antenna array codebook based on the determined type of coverage; and controlling the transmission of a second signal according to the selected antenna array codebook.

[0016] To accomplish the above and related ends, one or more aspects include the features fully described below and particularly pointed out in the claims. The following description and the accompanying drawings set forth in detail certain illustrative features of one or more aspects. However, these features are indicative of only a few of the various ways in which the principles of the various aspects may be employed, and the present description is intended to include all such aspects and their equivalents. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to be able to understand in detail the manner in which the above-mentioned features of the present disclosure are achieved, a more particular description of the content briefly summarized above may be made by reference to various aspects, some of which are shown in the accompanying drawings. However, it should be noted that the accompanying drawings only illustrate certain typical aspects of the present disclosure and therefore should not be considered as limiting the scope thereof, as the description may admit of other equally effective aspects.

[0018] Figure 1 is a block diagram conceptually illustrating an example telecommunications system in accordance with certain aspects of the present disclosure.

[0019] Figure 2 is a block diagram conceptually illustrating an example design of a base station (BS) and an example user equipment (UE) in accordance with certain aspects of the present disclosure.

[0020] Figure 3 is a block diagram illustrating an example transceiver front end in accordance with certain aspects of the present disclosure.

[0021] Figure 4A Millimeter wave (mmW) sensing by a UE is shown in accordance with certain aspects of the present disclosure.

[0022] Figure 4B mmW sensing using cross polarization (Xpol) is shown in accordance with certain aspects of the present disclosure.

[0023] Figure 4C mmW sensing using frequency modulated continuous wave (FMCW) radar is shown in accordance with certain aspects of the present disclosure.

[0024] Figure 5 Example Fast Fourier Transform (FFT) symbol values ​​from Xpol detection are shown in accordance with certain aspects of the present disclosure.

[0025] Figure 6 is an example graph of cross-polarization ratio (K) in the in-phase / quadrature (IQ) plane for detecting an object in front of an antenna in accordance with certain aspects of the present disclosure.

[0026] Figure 7 is a flow diagram of example operations for wireless communications in accordance with certain aspects of the present disclosure.

[0027] Figure 8 is an example graph of signal-to-noise ratios (SNRs) of vertically polarized components and horizontally polarized components in decibels (dB) for different scenarios in accordance with certain aspects of the present disclosure.

[0028] Fig. 9 shows the standard deviation (σ) of K values ​​for different scenarios according to certain aspects of the present disclosure. K ) and the average signal-to-noise ratio (SNR) of the vertical polarization component and the horizontal polarization componentm ) between the two.

[0029] Fig.10 shows σ for different scenarios according to certain aspects of the present disclosure K With SNR m An example linear relationship between , where the line represents the boundary between the open space (OS) and the detection boundary.

[0030] Fig.11 According to certain aspects of the present disclosure, K and SNR m Flowchart for determining parameters for OS.

[0031] Fig.12 is a flow diagram of example operations for wireless communications based on antenna array codebook selection in accordance with certain aspects of the present disclosure.

[0032] Like reference numbers and designations throughout the various drawings represent like elements. DETAILED DESCRIPTION

[0033] Certain aspects of the present disclosure provide techniques and apparatus for distinguishing whether an antenna of a user equipment (UE) is blocked by a covering (e.g., a protective rubber or plastic cover) or by human tissue (e.g., a finger or palm). The transmission power of an uplink (UL) signal can be adjusted accordingly, using a relatively higher transmission power for open space or a covering, and a relatively lower transmission power for human tissue.

[0034] The following description provides examples without limiting the scope, applicability or examples set forth in the claims. Without departing from the scope of the present disclosure, the functions and arrangements of the elements discussed may be changed. Various examples may omit, replace or add various processes or components as appropriate. For example, the described method may be performed in an order different from the order described, and various steps may be added, omitted or combined. In addition, the features described with respect to some examples may be combined in some other examples. For example, a device may be implemented using any number of aspects set forth herein, and a method may be practiced using any number of aspects set forth herein. In addition, the scope of the present disclosure is intended to cover such a device or method that may be practiced using other structures, functions or structures and functions other than the various aspects of the present disclosure set forth herein. It should be understood that any aspect of the present disclosure disclosed herein may be embodied by one or more elements of the claims. The word "exemplary" is used herein to mean "used as an example, instance or illustration". Any aspect described as "exemplary" herein is not necessarily interpreted as being preferred or superior to other aspects.

[0035] The techniques described herein can be used for various wireless communication technologies, such as LTE, CDMA, TDMA, FDMA, OFDMA, SC-FDMA and other networks. The terms "network" and "system" are often used interchangeably. A CDMA network can implement radio technologies such as Universal Terrestrial Radio Access (UTRA), cdma2000, etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. cdma2000 covers IS-2000, IS-95 and IS-856 standards. A TDMA network can implement radio technologies such as Global System for Mobile Communications (GSM). An OFDMA network can implement radio technologies such as NR (e.g., 5G RA), Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDMA, etc. UTRA and E-UTRA are part of the Global Mobile Telecommunications System (UMTS).

[0036] New Radio (NR) is an emerging wireless communication technology developed in conjunction with the 5G Technology Forum (5GTF). 3GPP Long Term Evolution (LTE) and Advanced LTE (LTE-A) are versions of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents from an organization called the "3rd Generation Partnership Project" (3GPP). cdma2000 and UMB are described in documents from an organization called the "3rd Generation Partnership Project 2" (3GPP2). The techniques described herein can be used for the above-mentioned wireless networks and radio technologies as well as other wireless networks and radio technologies. For clarity, although terms commonly associated with 3G and / or 4G wireless technologies may be used herein to describe various aspects, various aspects of the present disclosure may be applied to communication systems based on other generations, such as 5G and higher, including NR technologies.

[0037] NR access (e.g., 5G technology) can support various wireless communication services, such as enhanced mobile broadband (eMBB) for wide bandwidth (e.g., 80 MHz or above), millimeter wave (mmW) for high carrier frequencies (e.g., 24 GHz to 53 GHz or above), massive MTC (mMTC) for non-backward compatible machine type communication (MTC) technologies, and / or mission critical ultra-reliable low latency communication (URLLC). These services may include latency and reliability requirements. These services may also have different transmission time intervals (TTIs) to meet corresponding quality of service (QoS) requirements. In addition, these services can coexist in the same subframe.

[0038] Example Wireless Communication System

[0039] Figure 1 An example wireless communication network 100 is shown in which aspects of the present disclosure may be performed. A wireless device in the wireless network 100 may perform a method for determining an environmental scenario of an antenna (or antenna array) of a wireless device as further described herein. As used herein, an "environmental scenario" generally refers to whether an antenna (or antenna array) of a wireless device is blocked by an object (such as a protective cover or a human grip) or is not blocked by an object (this situation is referred to as "open space").

[0040] like Figure 1 As shown, the wireless network 100 may include multiple base stations (BS) 110 and other network entities. A BS may be a station that communicates with a user equipment (UE). Each BS 110 may provide communication coverage for a specific geographic area. In 3GPP, the term "cell" may refer to the coverage area of ​​a node B (NB) and / or a node B subsystem that provides services for the coverage area, depending on the context in which the term is used. In the NR system, the term "cell" and the next generation node B (gNB), new radio base station (NR BS), 5G NB, access point (AP) or transmission reception point (TRP) may be interchangeable. In some examples, the cell may not necessarily be stationary, and the geographical area of ​​the cell may move according to the location of the mobile BS. In some examples, the base stations may be interconnected to each other and / or to one or more other base stations or network nodes (not shown) in the wireless communication network 100 through various types of backhaul interfaces (such as direct physical connections, wireless connections, virtual networks, etc.) using any suitable transmission network.

[0041] Generally, any number of wireless networks can be deployed in a given geographic area. Each wireless network can support a specific radio access technology (RAT) and can operate on one or more frequencies. RAT can also be referred to as radio technology, air interface, etc. Frequency can also be referred to as carrier, subcarrier, frequency channel, tone, subband, etc. Each frequency can support a single RAT in a given geographic area to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks can be deployed.

[0042] A base station (BS) may provide communication coverage for macro cells, pico cells, femto cells, and / or other types of cells. A macro cell may cover a relatively large geographic area (e.g., a radius of several kilometers) and may allow unrestricted access to UEs with service subscriptions. A pico cell may cover a relatively small geographic area and may allow unrestricted access to UEs with service subscriptions. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access to UEs associated with the femto cell (e.g., UEs in a closed subscriber group (CSG), UEs of users in a home, etc.). A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In Figure 1 In the example shown, BSs 110a, 110b, and 110c may be macro BSs for macro cells 102a, 102b, and 102c, respectively. BS 110x may be a pico BS for pico cell 102x. BSs 110y and 110z may be femto BSs for femto cells 102y and 102z, respectively. One BS may support one or more (eg, three) cells.

[0043] The wireless communication network 100 may also include a relay station. A relay station is a station that receives transmissions of data and / or other information from an upstream station (e.g., a BS or UE) and sends transmissions of data and / or other information to a downstream station (e.g., a UE or BS). A relay station may also be a UE that relays transmissions for other UEs. Figure 1 In the example shown, a relay station 110r may communicate with the BS 110a and the UE 120r to facilitate communication between the BS 110a and the UE 120r. A relay station may also be referred to as a relay BS, a relay, or the like.

[0044] The wireless network 100 may be a heterogeneous network including different types of BSs, such as a macro BS, a pico BS, a femto BS, a relay, etc. These different types of BSs may have different transmission power levels, different coverage areas, and different effects on interference in the wireless network 100. For example, a macro BS may have a high transmission power level (e.g., 20 watts (W)), while a pico BS, a femto BS, and a relay may have a lower transmission power level (e.g., 1 watt).

[0045] The wireless communication network 100 may support synchronous or asynchronous operation. For synchronous operation, the BSs may have similar frame timings, and transmissions from different BSs may be roughly aligned in time. For asynchronous operation, the BSs may have different frame timings, and transmissions from different BSs may not be aligned in time. The techniques described herein may be used for both synchronous and asynchronous operation.

[0046] A network controller 130 may couple to a set of BSs and provide coordination and control for these BSs. Network controller 130 may communicate with BSs 110 via a backhaul. BSs 110 may also communicate with each other via a wireless or wired backhaul (eg, directly or indirectly).

[0047] UE 120 (e.g., 120x, 120y, etc.) may be dispersed throughout the wireless network 100, and each UE may be fixed or mobile. UE may also be referred to as a mobile station (MS), a terminal, an access terminal, a subscriber unit, a station, a customer premises equipment (CPE), a cellular phone, a smart phone, a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet computer, a camera, a gaming device, a netbook, a smartbook, an ultrabook, an appliance, a medical device or medical instrument, a biometric sensor / device, a wearable device (e.g., a smart watch, smart clothing, smart glasses, a smart bracelet, smart jewelry (e.g., a smart ring, a smart bracelet, etc.)), an entertainment device (e.g., a music device, a video device, a satellite radio, etc.), a vehicle-mounted component or sensor, a smart meter / sensor, an industrial manufacturing device, a global positioning system (GPS) device, or any other suitable device configured to communicate via a wireless or wired medium. Some UEs may be considered as machine type communication (MTC) devices or evolved MTC (eMTC) devices. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc. that can communicate with a BS, another device (e.g., a remote device), or some other entity. For example, a wireless node may provide connectivity to a network (e.g., a wide area network such as the Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered as Internet of Things (IoT) devices, which may be narrowband IoT (NB-IoT) devices.

[0048] Some wireless networks (e.g., LTE) use orthogonal frequency division multiplexing (OFDM) on the downlink and single carrier frequency division multiplexing (SC-FDM) on the uplink. OFDM and SC-FDM divide the system bandwidth into multiple (K) orthogonal subcarriers, which are also commonly referred to as tones, bins, etc. Each subcarrier can be modulated with data. Typically, modulation symbols are sent in the frequency domain using OFDM and in the time domain using SC-FDM. The spacing between adjacent subcarriers can be fixed, and the total number of subcarriers (K) can depend on the system bandwidth. For example, the spacing of the subcarriers can be 15kHz, and the minimum resource allocation (called a "resource block" (RB)) can be 12 subcarriers (or 180kHz). Therefore, for system bandwidths of 1.25, 2.5, 5, 10, or 20 megahertz (MHz), the nominal fast Fourier transform (FFT) size can be equal to 128, 256, 512, 1024, or 2048, respectively. The system bandwidth can also be divided into subbands. For example, one subband may cover 1.08 MHz (ie, 6 resource blocks), and there may be 1, 2, 4, 8, or 16 subbands for system bandwidths of 1.25, 2.5, 5, 10, or 20 MHz, respectively.

[0049] Although aspects of the examples described herein may be associated with LTE technology, aspects of the present disclosure may be applicable to other wireless communication systems such as NR. NR may use OFDM with a cyclic prefix (CP) on the uplink and downlink, and include support for half-duplex operation using time division duplex (TDD). Beamforming may be supported, and the beam direction may be dynamically configured. Multiple-input multiple-output (MIMO) transmission with precoding may also be supported. The MIMO configuration in the downlink (DL) may support up to 8 transmit antennas, multi-layer DL transmission with up to 8 streams, and up to 2 streams per UE. Aggregation of multiple cells of up to 8 serving cells may be supported.

[0050] In some examples, access to the air interface can be scheduled, where a scheduling entity (e.g., a base station) allocates resources for communications between some or all devices and devices (instruments) within its service area or cell. The scheduling entity can be responsible for scheduling, allocating, reconfiguring, and releasing resources for one or more subordinate entities. That is, for scheduling communications, the subordinate entity utilizes the resources allocated by the scheduling entity. The base station is not the only entity that can be used as a scheduling entity. In some examples, a UE can be used as a scheduling entity and can schedule resources for one or more subordinate entities (e.g., one or more other UEs), and other UEs can utilize the resources scheduled by the UE for wireless communications. In some examples, a UE can be used as a scheduling entity in a peer-to-peer (P2P) network and / or a mesh network. In the mesh network example, in addition to communicating with the scheduling entity, UEs can also communicate directly with each other.

[0051] exist Figure 1 In FIG. 1 , a solid double-arrow line indicates desired transmission between a UE and a serving BS, which is a BS designated to serve the UE on a downlink and / or uplink. A dashed line with double-arrows indicates interfering transmissions between a UE and a BS.

[0052] Figure 2 1 shows a BS 110 and a UE 120 (eg, Figure 1 For example, antenna 252, transceiver (TX / RX) front end circuit 254, processors 258, 264, and / or controller / processor 280 of UE 120 may be used to perform various techniques and methods described herein (e.g., Figure 7 Operation 700 or Fig.12 Operation 1200).

[0053] At BS110, the transmission processor 220 can receive data from the data source 212 and control information from the controller / processor 240. The control information can be for a physical broadcast channel (PBCH), a physical control format indicator channel (PCFICH), a physical hybrid ARQ indicator channel (PHICH), a physical downlink control channel (PDCCH), a group common PDCCH (GC PDCCH), etc. The data can be for a physical downlink shared channel (PDSCH), etc. The processor 220 can process (e.g., encode and symbol map) the data and the control information to obtain data symbols and control symbols, respectively. The processor 220 can also generate reference symbols, such as for a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a cell-specific reference signal (CRS). The transmission (TX) multiple-input multiple-output (MIMO) processor 230 can perform spatial processing (e.g., precoding) on ​​data symbols, control symbols, and / or reference symbols (if applicable), and can provide output symbol streams to the transmission (TX) front-end circuits 232a to 232t. Each TX front-end circuit 232 may process a corresponding output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each TX front-end circuit 232 may further process (e.g., convert to analog, amplify, filter, and up-convert) the output sample stream to obtain a downlink signal. The downlink signals from the TX front-end circuits 232a to 232t may be transmitted via antennas 234a to 234t, respectively.

[0054] At UE 120, antennas 252a to 252r may receive downlink signals from BS 110 and may provide received signals to receive (RX) front-end circuits 254a to 254r, respectively. Each RX front-end circuit 254 may condition (e.g., filter, amplify, downconvert, and digitize) a corresponding received signal to obtain input samples. Each RX front-end circuit 254 may further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. A MIMO detector 256 may obtain received symbols from all RX front-end circuits 254a to 254r, perform MIMO detection on the received symbols (if applicable), and provide detected symbols. A receive processor 258 may process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for UE 120a to a data sink 260, and provide decoding control information to a controller / processor 280. A memory 282 may store data and program codes for UE 120 and may interface with the controller / processor 280.

[0055] On the uplink, at the UE 120, the transmit processor 264 may receive and process data from a data source 262 (e.g., for a physical uplink shared channel (PUSCH)) and control information from a controller / processor 280 (e.g., for a physical uplink control channel (PUCCH)). The transmit processor 264 may also generate reference symbols for reference signals (e.g., for a sounding reference signal (SRS)). If applicable, the symbols from the transmit processor 264 may be precoded by a TX MIMO processor 266 for further processing by the RX front-end circuits 254a to 254r (e.g., for SC-FDM, etc.) and transmitted to the BS 110. At the BS 110, the uplink signal from the UE 120 may be received by the antenna 234, processed by the TX front-end circuit 232, detected by the MIMO detector 236 (if applicable), and further processed by the receive processor 238 to obtain decoded data and control information sent by the UE 120. Receive processor 238 may provide decoded data to data sink 239 and decoded control information to controller / processor 240. Memory 242 may store data and program codes for BS 110 and may interface with controller / processor 240.

[0056] Controllers / processors 240 and 280 may direct the operation at BS 110 and UE 120, respectively. Processor 240 and / or other processors and modules at BS 110 may perform or direct the execution of processes for the techniques described herein. Memories 242 and 282 may store data and program codes for BS 110 and UE 120, respectively. Scheduler 244 may schedule UEs for data transmission on the downlink and / or uplink.

[0057] Figure 3 is an example transceiver front end 300 (such as Figure 2 2, 254, etc.). The transceiver front end 300 includes at least one transmit (TX) path 302 (also referred to as a "transmit chain") for transmitting signals via one or more antennas and at least one receive (RX) path 304 (also referred to as a "receive chain") for receiving signals via the antenna. When the TX path 302 and the RX path 304 share an antenna 303, the path can be connected to the antenna via an RF interface 306, which can include any of a variety of suitable RF devices, such as a duplexer, a switch, a diplexer, etc.

[0058] To receive an in-phase (I) or quadrature (Q) baseband analog signal from a digital-to-analog converter (DAC) 308, the TX path 302 may include a baseband filter (BBF) 310, a mixer 312, a driver amplifier (DA) 314, and a power amplifier (PA) 316. The BBF 310, the mixer 312, and the DA 314 may be included in a radio frequency integrated circuit (RFIC), while the PA 316 may be included in the RFIC or outside the RFIC. The BBF 310 filters the baseband signal received from the DAC 308, and the mixer 312 mixes the filtered baseband signal with a transmission local oscillator (LO) signal to convert the baseband signal of interest to a different frequency (e.g., upconvert from baseband to RF). This frequency conversion process generates a sum and difference frequency between the LO frequency and the frequency of the baseband signal of interest. The sum and difference frequencies are referred to as beat frequencies. The beat frequency is typically in the RF range, so that the signal output by mixer 312 is typically an RF signal, which may be amplified by DA 314 and / or PA 316 before being transmitted by antenna 303 .

[0059] The RX path 304 may include a low noise amplifier (LNA) 322, a mixer 324, and a baseband filter (BBF) 326. The LNA 322, the mixer 324, and the BBF 326 may be included in a radio frequency integrated circuit (RFIC), which may or may not be the same RFIC that includes the TX path components. An RF signal received via the antenna 303 may be amplified by the LNA 322, and the mixer 324 mixes the amplified RF signal with a received local oscillator (LO) signal to convert the RF signal of interest to a different baseband frequency (i.e., down-convert). The baseband signal output by the mixer 324 may be filtered by the BBF 326 and then converted by an analog-to-digital converter (ADC) 328 into a digital I or Q signal for digital signal processing.

[0060] While it is desirable that the output of the LO remain stable in frequency, tuning to a different frequency may dictate the use of a variable frequency oscillator, which may involve a tradeoff between stability and tunability. Modern systems may employ a frequency synthesizer with a voltage controlled oscillator (VCO) to generate a stable, tunable LO with a specific tuning range. Thus, the transmit LO may be generated by a TX frequency synthesizer 318, which may be buffered or amplified by an amplifier 320 before being mixed with the baseband signal in mixer 312. Similarly, the receive LO may be generated by an RX frequency synthesizer 330, which may be buffered or amplified by an amplifier 332 before being mixed with the RF signal in mixer 324.

[0061] Example RF Exposure Assessment

[0062] RF exposure can be expressed in terms of specific absorption rate (SAR), which measures the energy absorbed per unit mass of human tissue and may be expressed in watts per kilogram (W / kg). Alternatively, RF exposure can be expressed in terms of power density (PD), which measures the energy absorbed per unit area and may be expressed in units of mW / cm 2 .

[0063] SAR can be used to assess RF exposure at transmission frequencies less than 6 GHz, which covers wireless communication technologies such as 3G (e.g., CDMA), 4G (e.g., LTE), 5G (e.g., NR in the 6 GHz band), IEEE 802.11ac, etc. PD can be used to assess RF exposure at transmission frequencies above 10 GHz, which covers wireless communication technologies such as IEEE802.11ad, 802.11ay, 5G, etc. Therefore, different indicators can be used to assess RF exposure of different wireless communication technologies.

[0064] A wireless device (e.g., UE 120) may transmit signals simultaneously using multiple wireless communication technologies. For example, a wireless device may transmit signals simultaneously using a first wireless communication technology (e.g., 3G, 4G, 5G, etc.) operating at or below 6 GHz and a second wireless communication technology (e.g., 5G, IEEE 802.11ad, or 802.11ay in a 24 to 60 GHz band) operating above 6 GHz. In some aspects, a wireless device may transmit signals simultaneously using a first wireless communication technology (e.g., 3G, 4G, 5G, IEEE 802.11ac, etc. in a 6 GHz band) and a second wireless communication technology (e.g., 5G, IEEE 802.11ad, 802.11ay, etc. in a 24 to 60 GHz band), in which RF exposure is measured according to SAR, and in which RF exposure is measured according to PD in the second wireless communication technology.

[0065] To assess RF exposure from transmissions using a first technology (e.g., 3G, 4G, 5G, IEEE 802.11ac in the 6 GHz band, etc.), the wireless device may include stored in a memory (e.g., Figure 2 Memory 282 or Figure 3 336) for the first technology. Each SAR distribution may correspond to a respective transmission scenario in a plurality of transmission scenarios supported by the wireless device for the first technology. The transmission scenario may correspond to an antenna (e.g., Figure 2 Antennas 252a to 252r or Figure 3 antenna 303), various combinations of frequency bands, channels and / or body locations, as further discussed below.

[0066] The SAR distribution (also referred to as a "SAR map") for each transmission scenario can be generated based on measurements (e.g., electric field measurements) performed in a test laboratory using a human body model. After the SAR distribution is generated, the SAR distribution can be stored in a memory for a processor (e.g., Figure 2 The processor 266 of the device can assess RF exposure in real time. Each SAR distribution includes a collection of SAR values, where each SAR value may correspond to a different location (e.g., on a model of the human body). Each SAR value may include a SAR value averaged over a mass of 1 g or 10 g at a corresponding location.

[0067] The SAR values ​​in each SAR distribution correspond to a specific transmit power level (e.g., the transmit power level at which the SAR values ​​were measured in a test laboratory). Since SAR scales with transmit power level, the processor can scale the SAR distribution for any transmit power level by multiplying each SAR value in the SAR distribution by the following transmit power scaling factor:

[0068]

[0069] Among them, Tx c is the current transmission power level of the corresponding transmission scenario, Tx SAR is the transmission power level corresponding to the SAR value in the stored SAR distribution (eg, the transmission power level at which the SAR value was measured in a test laboratory).

[0070] As described above, the wireless device may support multiple transmission scenarios for the first technology. In some aspects, the transmission scenario may be specified by a parameter set. The parameter set may include one or more of the following: (a) antenna parameters indicating one or more antennas (i.e., active antennas) used for transmission, (b) band parameters indicating one or more frequency bands (i.e., active bands) used for transmission, (c) channel parameters indicating one or more channels (i.e., active channels) used for transmission, (d) body position parameters indicating the position of the wireless device relative to the user's body position (head, torso, away from the body, etc.), and / or (e) other parameters. In the case where the wireless device supports a large number of transmission scenarios, performing measurements for each transmission scenario in a test setting (e.g., a test lab) may be very time-consuming and expensive. In order to reduce testing time, measurements may be performed on a subset of the transmission scenarios to generate a SAR distribution for the subset of the transmission scenarios. In this example, as further discussed below, the SAR distribution for each transmission scenario in the remaining transmission scenarios may be generated by combining two or more SAR distributions of the subset of the transmission scenarios.

[0071] For example, SAR measurements for each antenna may be performed to generate a SAR distribution for each antenna. In this example, a SAR distribution for a transmission scenario in which two or more antennas are active may be generated by combining the SAR distributions of the two or more active antennas.

[0072] In another example, SAR measurements for each of the plurality of frequency bands may be performed to generate a SAR distribution for each of the plurality of frequency bands. In this example, a SAR distribution for a transmission scenario in which two or more active frequency bands are active may be generated by combining the SAR distributions of the two or more active frequency bands.

[0073] In certain aspects, the SAR distribution can be normalized with respect to the SAR limit by dividing each SAR value in the SAR distribution by the SAR limit. In this case, when the normalized SAR value is greater than 1, the normalized SAR value exceeds the SAR limit, and when the normalized SAR value is less than 1, the normalized SAR value is below the SAR limit. In these aspects, each SAR distribution stored in the memory can be normalized with respect to the SAR limit.

[0074] In certain aspects, a normalized SAR distribution for a transmission scenario may be generated by combining two or more normalized SAR distributions. For example, a normalized SAR distribution for a transmission scenario in which two or more antennas are active may be generated by combining the normalized SAR distributions of two or more active antennas. For situations in which different transmission power levels are used for the active antennas, the normalized SAR distribution of each active antenna may be scaled by the corresponding transmission power level before combining the normalized SAR distributions of the active antennas. The normalized SAR distribution for simultaneous transmissions from multiple active antennas may be given by:

[0075]

[0076] SAR lim is the SAR limit, SAR norm_combined is the combined normalized SAR distribution transmitted simultaneously from the active antennas, i is the index of the active antenna, and SAR i is the SAR distribution of the ith active antenna, Tx i is the transmission power level of the ith active antenna, Tx SARi is the transmission power level of the SAR distribution of the i-th active antenna, and K is the number of active antennas.

[0077] Equation (2) can be rewritten as follows:

[0078]

[0079] SAR norm_iis the normalized SAR distribution of the ith active antenna. In the case of using multiple active antennas to transmit simultaneously at the same transmission frequency (e.g., multiple-input multiple-output (MIMO)), the combined normalized SAR distribution is obtained by summing the square roots of the individual normalized SAR distributions and calculating the square of the sum, as follows:

[0080]

[0081] In another example, the normalized SAR distributions for different frequency bands may be stored in a memory. In this example, a normalized SAR distribution for a transmission scenario in which two or more frequency bands are active may be generated by combining the normalized SAR distributions of two or more active frequency bands. For situations in which the transmission power levels of the active frequency bands are different, the normalized SAR distribution of each active frequency band may be scaled by the corresponding transmission power level before combining the normalized SAR distributions of the active frequency bands. In this example, the combined SAR distribution may also be calculated using equation (3a), where i is the index of the active frequency band and SAR is the index of the active frequency band. norm_i is the normalized SAR distribution of the ith active frequency band, Tx i is the transmission power level of the ith active frequency band, Tx SARi is the transmit power level of the normalized SAR distribution for the ith active frequency band.

[0082] To assess RF exposure from transmissions using a second technology (e.g., 5G in the 24 to 60 GHz band, IEEE 802.11ad, 802.11ay, etc.), the wireless device may include stored in a memory (e.g., Figure 2 Memory 282 or Figure 3 Each PD distribution may correspond to a corresponding transmission scenario in a plurality of transmission scenarios supported by the wireless device for the second technology. The transmission scenario may correspond to an antenna (e.g., Figure 2 Antennas 252a to 252r or Figure 3 antenna 303), various combinations of frequency bands, channels and / or body locations.

[0083] The PD distribution (also referred to as a "PD map") for each transmission scenario can be generated based on measurements (e.g., electric field measurements) performed in a test laboratory using a human body model. After the PD distribution is generated, the PD distribution can be stored in a memory for a processor (e.g., Figure 2 The processor 266 of the device can assess RF exposure in real time, as discussed further below. Each PD distribution includes a set of PD values, where each PD value can correspond to a different location (e.g., on a model of the human body).

[0084] The PD values ​​in each PD distribution correspond to a specific transmit power level (e.g., the transmit power level at which the PD values ​​were measured in a test lab). Since PD scales with transmit power level, the processor can scale the PD distribution for any transmit power level by multiplying each PD value in the PD distribution by the following transmit power scaling factor:

[0085]

[0086] Among them, Tx c is the current transmission power level of the corresponding transmission scenario, Tx PD is the transmission power level corresponding to the PD value in the PD distribution (eg, the transmission power level when the PD value is measured in a test laboratory).

[0087] As described above, the wireless device may support multiple transmission scenarios for the second technology. In some aspects, the transmission scenario may be specified by a parameter set. The parameter set may include one or more of the following: (a) antenna parameters indicating one or more antennas (i.e., active antennas) used for transmission, (b) band parameters indicating one or more frequency bands (i.e., active bands) used for transmission, (c) channel parameters indicating one or more channels (i.e., active channels) used for transmission, (d) body position parameters indicating the position of the wireless device relative to the user's body position (head, torso, away from the body, etc.), and / or (e) other parameters. In the case where the wireless device supports a large number of transmission scenarios, performing measurements for each transmission scenario in a test setting (e.g., a test lab) may be very time-consuming and expensive. In order to reduce testing time, measurements may be performed on a subset of the transmission scenarios to generate a PD distribution for the subset of the transmission scenarios. In this example, as further discussed below, the PD distribution for each transmission scenario in the remaining transmission scenarios may be generated by combining two or more PD distributions of a subset of the transmission scenarios.

[0088] For example, PD measurements may be performed for each antenna to generate a PD distribution for each antenna. In this example, a PD distribution for a transmission scenario in which two or more antennas are active may be generated by combining the PD distributions of the two or more active antennas.

[0089] In another example, PD measurement may be performed for each of the plurality of frequency bands to generate a PD distribution for each of the plurality of frequency bands. In this example, a PD distribution for a transmission scenario in which two or more active frequency bands are active may be generated by combining the PD distributions of the two or more active frequency bands.

[0090] In certain aspects, the PD distribution can be normalized relative to the PD limit by dividing each PD value in the PD distribution by the PD limit. In this case, when the normalized PD value is greater than 1, the normalized PD value exceeds the PD limit, and when the normalized PD value is less than 1, the normalized PD value is below the PD limit. In these aspects, each PD distribution stored in the memory can be normalized relative to the PD limit.

[0091] In certain aspects, a normalized PD distribution for a transmission scenario may be generated by combining two or more normalized PD distributions. For example, a normalized PD distribution for a transmission scenario in which two or more antennas are active may be generated by combining the normalized PD distributions for two or more active antennas. For situations in which different transmission power levels are used for the active antennas, the normalized PD distribution for each active antenna may be scaled by the corresponding transmission power level before combining the normalized PD distributions for the active antennas. The normalized PD distribution for simultaneous transmission of multiple active antennas may be given by:

[0092]

[0093] Among them PD lim is the PD limit, PD norm_combined is the combined normalized PD distribution transmitted simultaneously from the active antennas, i is the index of the active antenna, and PD i is the PD distribution of the ith active antenna, Tx i is the transmission power level of the ith active antenna, Tx PDi is the transmission power level of the PD distribution of the i-th active antenna, and L is the number of active antennas.

[0094] Equation (5) can be rewritten as follows:

[0095]

[0096] Among them PD norm_i is the normalized PD distribution of the i-th active antenna. In the case of using multiple active antennas to transmit simultaneously at the same transmission frequency (e.g., MIMO), the combined normalized PD distribution is obtained by summing the square roots of the individual normalized PD distributions and calculating the square of the sum, as shown below:

[0097]

[0098] In another example, the normalized PD distributions for different frequency bands may be stored in a memory. In this example, a normalized PD distribution for a transmission scenario in which two or more frequency bands are active may be generated by combining the normalized PD distributions of two or more active frequency bands. For situations in which the transmission power levels of the active frequency bands are different, the normalized PD distribution of each active frequency band may be scaled by the corresponding transmission power level before combining the normalized PD distributions of the active frequency bands. In this example, the combined PD distribution may also be calculated using equation (6a), where i is the index of the active frequency band and PD is the index of the active frequency band. norm_i is the normalized PD distribution of the ith activity band, Tx i is the transmission power level of the ith active frequency band, Tx PDi is the transmission power level of the normalized PD distribution for the ith active band.

[0099] Example method for distinguishing covering objects from human grasps

[0100] As mentioned above, in wireless communications, there are maximum permissible exposure (MPE) limits from international regulatory bodies, including the International Committee on Non-Ionizing Radiation Protection (ICNIRP) and the Federal Communications Commission (FCC) in the United States, which specify the highest power or energy density (in W / cm2) of an electromagnetic source that is considered safe. 2 or J / cm 2 In some cases, the MPE limit(s) may be converted into constraints related to the maximum transmit power of one or more devices (e.g., depending on the implementation of each device), and thus, uplink (UL) signals transmitted by the devices may be limited due to MPE compliance.

[0101] Some UEs may include sensors (e.g., millimeter wave (mmW) sensors) that allow higher UL transmission power levels if the sensor output shows that no objects blocking the UE antenna(s) are detected, potentially improving the UL throughput of transmissions at such higher power levels. For example, Figure 4A 1 shows mmW sensing performed by UE 120 using such an object detection sensor. Figure 4A In the embodiment, UE 120 includes at least one antenna array 400 having a plurality of antennas 402a-d (collectively referred to herein as “antennas 402”). In order to detect an object 404 ( Figure 4B and Figure 4CIn an open space (OS) condition, the UE 120 may output a signal (e.g., a continuous wave (CW), out-of-band signal) from one of the antennas 402 in the array 400 (e.g., from antenna 402a) having a specific detection angle 406, and another antenna in the array (e.g., antenna 402d) may receive a signal reflected from a surface of a nearby object 404 (such as a protective cover or a human hand or finger). For the reflected signal, the UE 120 may utilize the following method: Figure 4B The cross-polarization (Xpol) shown determines the cross-polarization ratio (K = k V / k H ) and detects whether an object 404 exists, wherein two polarization receiving paths in the circuit diagram 420, one polarization receiving path is used for horizontal polarization components (labeled as "H-pol"), and the other polarization receiving path is used for vertical polarization components (labeled as "V-pol"). Additionally or alternatively, UE 120 may use a frequency modulated continuous wave (FMCW) radar for object detection, such as Figure 4C As shown, an example frequency sweep and circuit diagram 460 is shown. Figure 4A As shown, Xpol may have an object detection radius 408 ranging from 0 to approximately 4 cm from the UE 120, while the FMCW radar may have an object detection radius ranging from approximately 4 cm to approximately 60 cm from the UE.

[0102] As mentioned above, Figure 4B mmW sensing using cross polarization (Xpol) to detect objects 404 near a UE or to detect OS conditions in accordance with certain aspects of the present disclosure is shown. Figure 4B In the circuit diagram 420, the antenna array 400 includes four antennas 402, but any suitable number of antennas may be used. In the circuit diagram 420, the transmission path (e.g., the transmission path 302) includes a frequency synthesizer (e.g., the TX frequency synthesizer 318) and an amplifier 421. The frequency synthesizer is used to generate a frequency (f CW ) is a CW signal out of band (e.g., between the first component carrier frequency band (CC1) and the second component carrier frequency band (CC2)). In this example, f CW The amplifier 421 can amplify the CW signal and drive the antenna 402a to wirelessly transmit the signal (eg, at a specific detection angle 406).

[0103] If there is an object 404 near the UE, the surface of the object may reflect the transmission signal, and another antenna in the antenna array 400 (e.g., antenna 402d) may receive the signal reflected from the surface of the object. For Xpol detection, the receiving path (e.g., receiving path 304) may include two polarization receiving paths, one for the horizontal polarization component (labeled as "H-pol") and the other for the vertical polarization component (labeled as "V-pol") in the circuit diagram 420. The H-pol receiving path includes an amplifier (e.g., a low noise amplifier 332 H ), mixer 324 H , filters (eg, baseband filter 326 H ) and ADC 328 H Similarly, the V-pol receive path includes an amplifier (e.g., a low noise amplifier 332 V ), mixer 324 V , filters (eg, baseband filter 326 V ) and ADC 328 V A frequency synthesizer (eg, RX frequency synthesizer 330) may generate a local oscillator (LO) signal (eg, having a frequency of 28.001 GHz, offset 100 MHz from the transmit signal) as a signal for the H-pol mixer 324. H and V-pol mixer 324 V The input for each of . Figure 4B These receive chain components in can be as described above with respect to Figure 3 The RF amplifier functions as described to amplify a received RF signal, mix the amplified RF signal with an LO signal to down-convert the signal, filter the mixed signal to focus on a baseband signal, and digitize the baseband signal.

[0104] The H-pol digitized signal and the V-pol digitized signal from the ADC may be sent to a processor 422, which may be implemented by a digital signal processor (DSP) or any other suitable processing system. The processor 422 may include a fast Fourier transform (FFT) module 424 and a frequency domain in-phase / quadrature (FD-IQ) module 426. The FFT module 424 may be used to convert the time domain digitized signal into frequency domain data, which may produce a maximum H-pol FFT value (kH) and a maximum V-pol FFT value (kV), as described below with respect to Figure 5 Using the frequency domain data, the FD-IQ module 426 can be used to plot the cross-polarization ratio (K = k V / k H), as shown in diagram 430. The location of open space (ie, no objects nearby) in the I / Q plane can be different from that of various objects, and in this way, Xpol can be used to determine whether an object is present.

[0105] As mentioned above, Figure 4C mmW sensing using FMCW radar to detect objects 404 near a UE or detect OS conditions in accordance with certain aspects of the present disclosure is shown. Figure 4C , antenna array 400 includes four antennas 402, but any suitable number of antennas may be used. In circuit diagram 460, a transmission path (e.g., transmission path 302) includes DAC 308, baseband filter 310, mixer 312, and amplifier 421, which may represent DA 314 and / or PA 316. Frequency synthesizer 462 may be used to generate an LO signal for input to mixer 312. Frequency synthesizer 462, in conjunction with other components of the transmission path, may be used to generate a frequency sweep (e.g., from 25 to 29 GHz), which may include CC1 and CC2 bands in a wireless transmission signal output from antenna 402a, as shown.

[0106] If there is an object 404 near the UE, the surface of the object may reflect the transmission signal, and another antenna (e.g., antenna 402d) in the antenna array 400 may receive the signal reflected from the surface of the object. For FMCW radar detection, the receiving path (e.g., receiving path 304) may include a low noise amplifier 332, a mixer 324, a baseband filter 326), and an ADC 328. Figure 4C These receive path components in the circuit diagram 460 may be as described above with respect to Figure 3 The ADC 328 functions as described above to amplify the received RF signal, mix the amplified RF signal with the LO signal from the frequency synthesizer 462 to down-convert the signal, filter the mixed signal to focus on the baseband signal, and digitize the baseband signal. The FMCW digitized signal from the ADC 328 can be sent to the processor 464, which can be implemented by a DSP or any other suitable processing system. The processor 464 can process the FMCW digitized signal to detect an object or an open space condition.

[0107] Figure 5 5 shows example FFT symbol values ​​from Xpol detection according to certain aspects of the present disclosure. The FFT symbol values ​​include horizontal polarization FFT values ​​510 based on the digitized signal from the H-pol receive path and vertical polarization FFT values ​​520 based on the digitized signal from the V-pol receive path. The maximum value of the horizontal polarization FFT value 610 indicates k H , and the maximum value of the vertical polarization FFT value 620 indicates kV The cross-polarization ratio (K) is given by K = k V / k H Sure.

[0108] The complex value of K(I+jQ) provides an indication of the presence of an object in front of the antenna. V / k H Partition (which can be implemented as k V k H *) It is possible to eliminate the calibration of the transmission gain / phase randomness during each measurement. Figure 6 is an example graph 600 of multiple samples of K in the in-phase / quadrature (IQ) plane for two different scenarios: open space and finger grasp (or protective case).

[0109] The standard deviation of K consecutive measurements over time (σ K ) provides a measure of the stability of the object in front of the antenna. In other words, a relatively large σ K indicates less object stability (i.e., more object motion), while a relatively small σ K = indicates greater stability (i.e., less object motion). Open space (i.e., no reflectors) provides a relatively small σ K Human fingers or hands not grasping the UE in front of the antenna provide a relatively large σ K , but finger gripping UE provides a relatively small σ K , because in a partial grip, the finger does not move that much. Similar to the gripping finger, the protective shell (e.g., made of plastic and / or glass) also provides a smaller σ K , so it is difficult to use only σ K to distinguish between a protective cover and a human grasp. Figure 6 As shown in the example graph 600, the σ of the open space K Can be similar to the σ of a protective case (or finger grip) K .

[0110] When the antenna is blocked by a protective cover, the UE can use a higher transmission power, but when the antenna is blocked by a finger or other human tissue, a lower transmission power should be used due to the limitation of MPE, as described above. Therefore, techniques and devices are needed that can distinguish between a protective cover and a human grasp by the UE's object detection sensor.

[0111] Furthermore, different protective shells may provide different cross-polarization ratio centers {mean (K)} in the IQ plane. The algorithm used to determine the transmit power may periodically adjust the open space parameters of the UE, which, when combined with the different K centers of different protective shells, may also make it more difficult to distinguish between protective shells and finger grips.

[0112] Certain aspects of the present disclosure provide techniques and apparatus for distinguishing whether an antenna of a UE is blocked by a covering (e.g., a protective rubber or plastic housing) or by human tissue (e.g., a finger or palm) using at least two different types of parameters, as described in more detail below.

[0113] Figure 7 700 is a flow diagram illustrating example operations 700 for wireless communications in accordance with certain aspects of the present disclosure. Operations 700 may be performed, for example, by a wireless device (e.g., Figure 1 UE 120) and more specifically executed by a receiver, a processor and a transmitter of the wireless device.

[0114] Operations 700 may begin at block 701 with the wireless device transmitting a first signal (e.g., using the TX front end circuitry 254-254r or the transmit path 302 of the UE 120), and at block 702, receiving a plurality of signals (e.g., using the RX front end circuitry 254-254r or the receive path 304 of the UE 120) based on the transmitted first signal (e.g., reflections of the transmitted first signal). At block 704, the wireless device determines values ​​of at least two different types of parameters based on the received plurality of signals (e.g., using the receive processor 258, the control / processor 280, and / or the transmit processor 264 or using the processor 422 of the UE 120). At block 706, the wireless device determines an environmental scenario of the device based on the values ​​of the at least two different types of parameters (e.g., using the receive processor 258, the control / processor 280, and / or the transmit processor 264 or using the processor 422 of the UE 120). At block 708, the wireless device transmits a second signal (eg, using the TX front end circuitry 254-254r or the transmit path 302 of the UE 120) using a transmit power based on the determined environmental scenario. Operations 700 are described in greater detail below and illustrated in the various figures.

[0115] As mentioned above, σ K may not be sufficient to distinguish between a protective cover and a human grasp. Therefore, certain aspects of the present disclosure provide a method other than σ K For certain aspects, the additional information may be determined based on the FFT data already provided by the two polarization receive paths.

[0116] For example, empirical studies have shown that the signal-to-noise ratio (SNR) from the FFT of H-pol and V-pol fluctuates with different types of objects. V ) can be expressed as SNR V =10*log 10 (k V / σ 2FFTV ), where σ 2 FFTV is the variance of the vertical polarization FFT value (e.g., FFT value 520). The horizontal polarization component (SNR H ) can be expressed as SNR H =10*log 10 (k H / σ 2 FFTH ), where σ 2 FFTH is the variance of the horizontal polarization FFT value (e.g., FFT value 510). The mean SNR of these two SNRs (SNR m ) can be expressed as SNR m =SNR V -(SNR H -SNR V ). A processor (e.g., processor 422) that calculates FFT values ​​may calculate the value corresponding to k H or k V The noise power of a number of bins adjacent to the peak (eg, 20 adjacent bins, with 10 bins on either side of the peak). For certain aspects, the processor may remove or otherwise effectively ignore bins with spurs.

[0117] Electromagnetic (EM) simulations show that the near-field coupled electric field varies with the dielectric that simulates a human finger. The observed SNR fluctuations assume that the coupled signal power fluctuates relative to a fixed receiver noise floor (e.g., according to kTBFG, where k is the Boltzmann constant, T is absolute temperature, F is the noise figure, B is the receive bandwidth, and G is the gain) and is material type dependent due to the material's reflection coefficient.

[0118] Figure 8 is an example graph 800 of SNR in decibels (dB) for the vertical polarization component and the horizontal polarization component for different scenarios, including open space (OS), grip, and protective case. Thus, with this additional information, the same σ K Different environmental scenarios can also be viewed by viewing the SNR m to distinguish.

[0119] Fig. 9 An example graph 900 of K for different scenarios in the IQ plane is shown. In IQ graph 900, an orthogonal human finger pressing on the UE has a relatively very large σ K , as shown in the distribution of K values. In contrast, the open space and the human palm pressing on the UE have similar relatively small σ K , the rubber case and a vertical human finger pressing on the UE have similar but significantly larger σ KTherefore, only considering σ K It may be difficult to distinguish between open space, protective shell, or human tissue conditions.

[0120] Fig. 9 Also shown is a graph 950 showing the σ of the same scenario presented in IQ graph 900 in accordance with certain aspects of the present disclosure. K With SNR m 950 . An example correlation between . Using regression or any other various suitable techniques, a linear equation can be found to distinguish between scenes that can be classified as OS (e.g., OS or protective cover) and scenes that can be classified as object detection (e.g., presence of human tissue) for use in determining transmit power. Line 952 represented by the linear equation in graph 950 can be considered to be the boundary separating the two regions (OS region and object detection region). The threshold standard deviation (σ) of the OS / detection boundary line 952 is TH ) can be expressed as σ TH =m*SNR m +c, where m is the slope of the line and c is σ K Offset.

[0121] Fig.10 is a diagram showing different scenarios (eg, different materials) according to certain aspects of the present disclosure. K With SNR m Graph 1000 of an example linear relationship between , with equation σ TH =m*SNR m The line 1002 of +c represents the boundary between open space (OS) and the object detection area. Note how the air, rubber protective shell and plastic phone back shell are in the OS area, while the horizontal human finger pressed, the human palm pressed, the orthogonal human finger pressed and the vertical human finger pressed are in the detection area. The linear equation can be frequency or frequency band dependent. Additionally or alternatively, the linear equation can depend on the specific UE and vary between types, brands and models.

[0122] Fig.11 is a method for using σ based on certain aspects of the present disclosure. K and SNR m Flowchart 1100 for determining parameters of an OS. The parameters of an OS may include a radius (R OS ) and center (C OS ). As shown in flowchart 1100, if σ K <σ TH (indicating the OS region), the OS parameters can be updated, where R OS =3*σ K And among them C OS= mean(K). Otherwise, the OS parameters are not updated and more samples are captured. More specifically, samples (e.g., Xpol samples) are captured at block 1102, and an FFT is performed on the captured samples at block 1104 to convert the sampled data from the time domain to the frequency domain. As described above, based on the FFT, σ can be determined at block 1106. K , and the SNR may be determined at block 1108 m At block 1110, variables (e.g., m and c) of a linear equation for a boundary between open space and an object detection region (e.g., line 952 or line 1002) may be determined (e.g., read from a memory, such as memory 282). At block 1112, the variables of the linear equation and the SNR may be used to calculate the boundary between the open space and the object detection region (e.g., line 952 or line 1002). m To calculate σ TH If it is determined at block 1114 that σ K <σ TH (indicating the OS region), then update the OS parameters at block 1116, where ROS = 3*σ K And among them C OS = mean(K). Otherwise, if σ is determined at block 1114 K ≥σ TH , the OS parameters are not updated and more samples are captured at box 1102.

[0123] As described above, certain aspects of the present disclosure relate to a method for wireless communication by a UE. The method generally includes receiving a plurality of signals at the UE, determining values ​​of at least two different types of parameters based on the received plurality of signals, determining an environmental scenario of the UE based on the values ​​of the at least two different types of parameters, and transmitting a signal using a transmission power based on the determined environmental scenario.

[0124] According to certain aspects, the received multiple signals include a vertical polarization component signal and a horizontal polarization component signal. For certain aspects, at least two different types of parameters include statistics of a cross-polarization ratio between the vertical polarization component signal and the horizontal polarization component signal. For example, the statistics of the cross-polarization ratio may be a standard deviation of the cross-polarization ratio. For certain aspects, at least two different types of parameters also include statistics of a signal-to-noise ratio based on the vertical polarization component signal and the horizontal polarization component signal. For example, the statistics of the signal-to-noise ratio may be a mean of the signal-to-noise ratio calculated based on the variance of the vertical polarization component signal and the variance of the horizontal polarization component signal.

[0125] According to certain aspects, the at least two different types of parameters include statistics based on signal-to-noise ratios of the vertically polarized component signal and the horizontally polarized component signal.

[0126] According to certain aspects, receiving the multiple signals entails receiving a vertically polarized component signal via a vertically polarized receive path of the UE and receiving a horizontally polarized component signal via a horizontally polarized receive path of the UE.

[0127] According to certain aspects, the method further includes transmitting a test signal from the UE. In some cases, the test signal can be a continuous wave (CW) signal or a frequency modulated continuous wave (FMCW) radar signal. For certain aspects, the test signal is transmitted from an antenna in an antenna array of the UE, and the plurality of signals is received by another antenna in the antenna array.

[0128] According to certain aspects, determining the environmental scene requires distinguishing whether the UE's antenna is blocked by a covering or by human tissue. For example, the covering may include a protective case for the UE.

[0129] According to certain aspects, determining the environmental scene involves determining a center and a radius of an open space from an antenna of the UE.

[0130] According to certain aspects, determining the environmental scenario includes determining a line (e.g., a line such as line 952 or line 1002) based on a linear relationship between at least two types of parameters and determining whether one of the at least two types of parameters is above the line. In this case, if one of the at least two types of parameters is above the line, a relatively low transmission power may be used to transmit a signal, and if one of the at least two types of parameters is not above the line, a relatively high transmission power may be used to transmit a signal. For certain aspects, the parameters of the line (e.g., slope and offset) may be stored in a memory.

[0131] According to certain aspects, determining the environmental scenario includes determining a boundary based on a relationship between at least two types of parameters, and determining whether one of the at least two types of parameters is on a first side of the boundary or on a second side of the boundary. In this case, if one of the at least two types of parameters is on the first side of the boundary, a relatively low transmission power may be used to transmit the signal, and if one of the at least two types of parameters is on the second side of the boundary, a relatively high transmission power may be used to transmit the signal.

[0132] According to certain aspects, determining the environmental scenario includes determining a material of a protective shell covering the UE. For certain aspects, the received multiple signals include a vertically polarized component signal and a horizontally polarized component signal, and the at least two different types of parameters include statistics of a cross-polarization ratio between the vertically polarized component signal and the horizontally polarized component signal. In this case, determining the material of the protective shell covering the UE can be based at least in part on the statistics of the cross-polarization ratio. For example, the statistics can be a standard deviation of the cross-polarization ratio.

[0133] Example Cover Detection

[0134] As described above, the demodulated signal in the complex IQ domain has unique values ​​for open space (no objects), human objects, or coverings (e.g., protective shells). Both human objects and coverings can be interpreted as objects that trigger detection relative to the factory calibrated or characterized open space. However, if the original equipment manufacturer (OEM) knows the complex IQ domain value of the covering, this value can be input into the UE detection algorithm to further distinguish human objects from coverings.

[0135] In the case where the unique value of the covering is not known, detection techniques can be used. For example, as described above, each material exhibits a complex IQ domain value (e.g., σ K ) and the SNR difference between the horizontal and vertical polarization components (e.g. Figure 6 and Fig. 9 For certain aspects, open spaces classified as having a cover and detected objects classified as having a cover can also be distinguished by a detection algorithm that queries a database of characterized materials and scenes (e.g., as shown in FIG. Fig. 9 and Fig.10 shown).

[0136] The material of the protective cover covering the mmW antenna array (e.g., array 400) can negatively impact the performance of the UE. For certain aspects, upon detection of a cover (or more specifically the material constituting the cover), a cover material specific antenna array codebook (rather than an array codebook intended for uncovered UEs) can be selected to improve performance. For example, the UE can be pre-programmed with a codebook associated with a specific complex IQ value for a known cover (e.g., a first-party cover). After detecting the material of the cover via a specific complex IQ value, a pre-programmed codebook can be selected, which can improve mmW performance.

[0137] According to certain aspects, as described above, a cover-specific detection scheme (e.g., based on a radio frequency identification (RFID) tag, etc.) can be used in conjunction with the detection algorithm. For example, if the cover includes some form of wireless ID contained in the tag, covers with similar material detection characteristics can be further verified (e.g., a first-party protective case and a third-party "knockoff" case made of the same material(s) with similar dimensions). For certain aspects, the tag can also be pre-programmed to include material characteristics of the cover, which can be verified by the detection algorithm described herein for selection of an appropriate array codebook. The added layer of verification can, for example, assist with security compliance and / or allow for further customization of the codebook (e.g., cover-specific versus cover-material-specific).

[0138] Fig.121 is a flow diagram of example operations 1200 for wireless communication based on antenna array codebook selection in accordance with certain aspects of the present disclosure. Operations 1200 may be performed, for example, by a wireless device (e.g., Figure 1 UE 120) and more specifically executed by a receiver, a processor and a transmitter of the wireless device.

[0139] Operations 1200 may begin at block 1201 with the wireless device transmitting a first signal (e.g., from an antenna array and using the TX front-end circuitry 254-254r or the transmit path 302 of the UE 120). At block 1202, the wireless device receives a plurality of signals based on the transmitted first signal (e.g., using the RX front-end circuitry 254-254r or the receive path 304 of the UE 120). At block 1204, the wireless device determines a value for each of one or more parameters based on the received plurality of signals (e.g., using the processor 422). At block 1206, the wireless device determines a type of coverage adjacent to the antenna array of the device based on the value of each of the one or more parameters (e.g., using the processor 422). At block 1208, the wireless device selects an antenna array codebook based on the determined type of coverage (e.g., using the processor 422). At block 1210, the wireless device transmits a second signal (from the antenna array) according to the selected antenna array codebook (eg, using the TX front end circuitry 254-254r or the transmit path 302 of the UE 120).

[0140] According to certain aspects, determining the type of covering requires determining the material of the covering at block 1206. For example, the material of the covering may include at least one of plastic or rubber.

[0141] According to certain aspects, the cover comprises a protective case for the UE.

[0142] According to certain aspects, the received multiple signals include a vertically polarized component signal and a horizontally polarized component signal. For certain aspects, one or more parameters include statistics of the cross-polarization ratio between the vertically polarized component signal and the horizontally polarized component signal. For example, the statistics of the cross-polarization ratio may be the standard deviation of the cross-polarization ratio. For certain aspects, the value of the cross-polarization ratio is plotted over time in an in-phase / quadrature (IQ) plane. For certain aspects, one or more parameters also include statistics of a signal-to-noise ratio based on the vertically polarized component signal and the horizontally polarized component signal. In this case, the statistics of the signal-to-noise ratio may be the mean of the signal-to-noise calculated based on the variance of the vertically polarized component signal and the variance of the horizontally polarized component signal. For certain aspects, receiving multiple signals involves receiving the vertically polarized component signal via the vertically polarized receiving path of the UE and receiving the horizontally polarized component signal via the horizontally polarized receiving path of the UE.

[0143] According to certain aspects, the first signal may be a test signal transmitted from the wireless device. In this case, the transmitted test signal may be reflected by the covering to generate multiple signals received at the device. The test signal may include, for example, a continuous wave signal or a frequency modulated continuous wave (FMCW) radar signal.

[0144] According to certain aspects, operation 1200 also involves wirelessly reading an identification tag associated with the cover. For example, the identification tag can be a radio frequency identification (RFID) tag. For certain aspects, determining the type of the cover at block 1206 requires comparing the type of the cover determined based on the value of each of the one or more parameters with the type of the cover based on the read identification tag. For certain aspects, the cover is a protective case for the UE, in which case the identification tag can indicate a specific model of the protective case.

[0145] in conclusion

[0146] Certain aspects of the present disclosure use a signal processing algorithm with statistics to distinguish whether an antenna of a user equipment (UE) is blocked by a covering (e.g., a protective rubber or plastic housing) or by human tissue (e.g., a finger or palm). This provides increased uplink (UL) throughput while meeting regulatory RF exposure limits when the object is not present. As described above, an antenna array can transmit a weak CW signal from one of the antennas therein. One of the adjacent antennas in the array can receive a near-field mmW electromagnetic (EM) field and monitor perturbations in the EM field by looking at the complex FFT values ​​of two polarization receivers (e.g., H-pol and V-pol receive paths). By analyzing the standard deviation and SNR ratio of the CW peak complex values ​​of the two polarization receivers, aspects of the present disclosure can determine what type of material or head grip is present at or near the surface of the antenna, or at least be able to distinguish between a covering and human tissue.

[0147] The various operations of the above methods may be performed by any suitable means capable of performing the corresponding functions. The means may include various hardware and / or software components and / or modules, including but not limited to circuits, application specific integrated circuits (ASICs), or processors. Generally, where there are operations shown in the figures, these operations may have corresponding means plus functions. For example, the components for receiving may include Figure 2 RX front-end circuit 254-254r or Figure 3 The receiving path 304. The components for transmitting may include Figure 2 TX front-end circuit 254-254r or Figure 3 The transmission path 302. The means for determining and / or the means for selecting may include at least one processor, such as Figure 2The receive processor 258, the controller / processor 280 and / or the transmit processor 264 or Figure 4B Processor 422.

[0148] As used herein, the term "determine" includes a variety of actions. For example, "determine" may include calculating, computing, processing, deriving, investigating, searching (e.g., searching in a table, a database, or another data structure), determining, etc. In addition, "determine" may include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory), etc. In addition, "determine" may include parsing, selecting, choosing, establishing, etc.

[0149] As used herein, a phrase referring to "at least one" of a list of items refers to any combination of those items, including single members. For example, "at least one of a, b, or c" is intended to cover: a, b, c, ab, ac, bc, and abc, as well as any combination with multiples of the same element (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, and ccc, or any other order of a, b, and c).

[0150] The various illustrative logical blocks, modules, and circuits described in conjunction with the present disclosure may be implemented or executed with a general purpose processor, a digital signal processor (DSP), an ASIC, a field programmable gate array (FPGA) or other programmable logic device (PLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof, designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in an alternative, the processor may be any commercially available processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0151] The method disclosed herein includes one or more steps or actions for implementing the described method. Without departing from the scope of the claims, the method steps and / or actions can be interchangeable with each other. In other words, unless a specific order of steps or actions is specified, the order and / or use of specific steps and / or actions can be modified without departing from the scope of the claims.

[0152] If implemented in hardware, an example hardware configuration may include a processing system in a wireless node. The processing system may be implemented using a bus architecture. Depending on the specific application and overall design constraints of the processing system, the bus may include any number of interconnected buses and bridges. The bus may link various circuits including a processor, a machine-readable medium, and a bus interface together. The bus interface may be used to connect a network adapter, etc., to the processing system via the bus. The network adapter may be used to implement signal processing functions at the physical (PHY) layer. In the case of a user terminal, a user interface (e.g., a keyboard, a display, a mouse, a joystick, etc.) may also be connected to the bus. The bus may also link various other circuits that are well known in the art and therefore will not be further described, such as timing sources, peripherals, voltage regulators, power management circuits, etc.

[0153] The processing system may be configured as a general purpose processing system having one or more microprocessors providing processor functionality and an external memory providing at least a portion of a machine-readable medium, all linked together with other supporting circuitry via an external bus architecture. Alternatively, the processing system may be implemented with an ASIC having a processor, a bus interface (a user interface in the case of an access terminal), supporting circuitry, and at least a portion of a machine-readable medium integrated into a single chip, or implemented with one or more FPGAs, PLDs, controllers, state machines, gating logic, discrete hardware components, or any combination of circuits that can perform the various functions described throughout this disclosure. Those skilled in the art will recognize how to best implement the described functions for the processing system depending on the specific application and the overall design constraints imposed on the entire system.

[0154] It is to be understood that the claims are not limited to the precise configuration and components described above. Various modifications, changes and variations may be made in the arrangement, operation and details of the methods and apparatus described above without departing from the scope of the claims.

Claims

1. A method for wireless communication by a wireless device, comprising: wirelessly reading an identification tag associated with a cover covering at least a portion of the wireless device; determining a type of the covering based on the identification tag associated with the covering; transmitting a signal based on the determined type of the covering; as well as Based on the determined type of the coverage, an antenna array codebook is selected from a plurality of predefined antenna array codebooks, wherein the transmitting comprises transmitting the signal according to the selected antenna array codebook.

2. The method of claim 1, wherein the covering is a protective case for the wireless device, and wherein the identification label indicates a specific model of the protective case.

3. The method of claim 1, wherein determining the type of the covering comprises comparing the type of the covering determined based on the identification tag with the type of the covering determined using a detection technique.

4. The method of claim 3, wherein the detection technique comprises: transmitting another signal from the wireless device; receiving a plurality of signals at the wireless device based on the transmitted another signal, wherein the received plurality of signals include a vertically polarized component signal and a horizontally polarized component signal; and The type of the covering is determined based on the vertical polarization component signal and the horizontal polarization component signal.

5. The method of claim 4, wherein in the detection technique, the type of the covering is determined based on at least one of: statistical data of a cross-polarization ratio between the vertically polarized component signal and the horizontally polarized component signal; or The method further comprises: determining a signal-to-noise ratio of the vertical polarization component signal and the horizontal polarization component signal based on the signal-to-noise ratio of the vertical polarization component signal and the horizontal polarization component signal. The method of claim 1 , wherein the identification tag indicates one or more properties of the covering.

7. The method of claim 1, wherein a transmission power of the signal is based on the determined type of the covering and a radio frequency (RF) exposure limit. The method of claim 1 , wherein the identification label indicates a material of the covering.

9. An apparatus for wireless communication, comprising: a receiver configured to wirelessly read an identification tag associated with a covering covering at least a portion of the apparatus; a processing system configured to determine a type of the covering based on the identification tag associated with the covering; a transmitter configured to transmit a signal from the device; as well as an antenna array coupled to the transmitter, wherein: The processing system is further configured to select an antenna array codebook from a plurality of predefined antenna array codebooks based on the determined type of the covering; as well as The transmitter is configured to transmit the signal via the antenna array according to the selected antenna array codebook.

10. The apparatus of claim 9, wherein to determine the type of the covering, the processing system is configured to compare the type of the covering determined based on the identification tag with the type of the covering determined using a detection technique.

11. The apparatus of claim 10, wherein the apparatus is configured to perform the detection technique, the configuration for performing the detection technique comprising: a transmitter configured to transmit another signal from the device; a receiver configured to receive a plurality of signals at the device based on the transmitted another signal, wherein the received plurality of signals include a vertically polarized component signal and a horizontally polarized component signal; and The processing system is configured to determine the type of the covering based on the vertical polarization component signal and the horizontal polarization component signal.

12. The apparatus of claim 11, the processor configured to use the detection technique to determine the type of the covering based on at least one of: statistical data of a cross-polarization ratio between the vertically polarized component signal and the horizontally polarized component signal; or The method further comprises: determining a signal-to-noise ratio of the vertical polarization component signal and the horizontal polarization component signal based on the signal-to-noise ratio of the vertical polarization component signal and the horizontal polarization component signal.

13. The apparatus of claim 9, wherein the identification tag indicates one or more attributes of the covering.

14. The device of claim 9, wherein the identification label indicates a material of the covering.

15. The apparatus of claim 9, wherein the covering is a protective case for the wireless device, and wherein the identification label indicates a specific model of the protective case.

16. The apparatus of claim 9, wherein a processing system is configured to determine a transmission power of the signal based on the determined type of the covering and a radio frequency (RF) exposure limit.

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