Method and apparatus for user equipment to distinguish human grasp and protective cover

Abstract

Methods and apparatuses for distinguishing whether an antenna of a user equipment (UE) is blocked by a cover or by human tissue. Uplink signal transmission power can be adjusted accordingly, with higher transmission power for open space (OS) or cover, and lower transmission power for human tissue. One example method for wireless communication by a UE generally includes receiving a plurality of cross-polarization captures from a plurality of antenna arrays of the UE, detecting that the cross-polarization captures correspond to a first OS circle in an in-phase / quadrature (IQ) plane outside of a set of possible OS circles of the UE, assigning the first OS circle as an active OS circle of the UE based on the detecting, and deactivating other possible OS circles in the set, determining an environmental scenario corresponding to the active OS circle, and transmitting a signal using a transmission power based on the determined environmental scenario.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Application 17 / 166,501, filed February 3, 2021, which claims the benefit and priority to U.S. Provisional Application 62 / 986,528, filed March 6, 2020, both of which are incorporated herein by reference in their entirety for all applicable purposes. Technical Field

[0003] Certain aspects of this disclosure generally relate to wireless devices, and more specifically, to distinguishing between a human grip and a protective cover on a wireless device. Background Technology

[0004] Modern wireless devices, such as cellular phones, typically need to meet radio frequency (RF) exposure limits set by national and international standards and regulations. To ensure compliance, such devices must undergo an extensive certification process before being shipped to the market. To ensure compliance with RF exposure limits, technologies have been developed to enable wireless devices to assess RF exposure in real time and adjust their transmit power accordingly to meet these limits. Summary of the Invention

[0005] The systems, methods, and apparatuses of this disclosure each have several aspects, none of which is solely responsible for their desired properties. Without limiting the scope of this disclosure as set forth by the appended claims, some features will now be briefly discussed. Upon consideration of this discussion, and especially after reading the section entitled "Detailed Description," it will become apparent how the features of this disclosure provide advantages including improved systems and methods for assessing RF exposure from wireless devices.

[0006] Certain aspects of this disclosure provide a method for wireless communication by a user equipment (UE). The method typically includes: receiving multiple signals at the UE; determining values ​​for at least two different types of parameters based on the received multiple signals; determining an environmental scenario for the UE based on the values ​​of the at least two different types of parameters; and transmitting signals using a transmission power based on the determined environmental scenario.

[0007] Certain aspects of this disclosure provide a method for wireless communication by a UE. The method typically includes: receiving a plurality of signals at the UE; determining a value for each of one or more parameters based on the received plurality of signals; determining a type of cover 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 cover; and transmitting signals according to the selected antenna array codebook.

[0008] Certain aspects of the present disclosure provide a method of wireless communication by a UE. The method generally includes receiving a plurality of cross-polarization captures from a plurality of antenna arrays of the UE, detecting that the plurality of cross-polarization captures from the plurality of antenna arrays correspond to a first open space (OS) circle in an in-phase / quadrature (IQ) plane in a set of possible OS circles of the UE, assigning the first OS circle as an active OS circle of the UE and deactivating other possible OS circles in the set based on the detection, determining an environmental scenario corresponding to the active OS circle, and transmitting a signal using a transmission power based on the determined environmental scenario.

[0009] Certain aspects of the present disclosure provide an apparatus for wireless communication. The apparatus generally includes a receiver, a transmitter, a memory, and a processor. The receiver is configured to receive a plurality of cross-polarization captures from a plurality of antenna arrays. The processor is coupled to the memory, and the processor and the memory are configured to detect that the plurality of cross-polarization captures from the plurality of antenna arrays correspond to a first open space (OS) circle in an in-phase / quadrature (IQ) plane in a set of possible OS circles of the apparatus, assign the first OS circle as an active OS circle of the apparatus and deactivate other possible OS circles in the set based on the detection, and determine an environmental scenario corresponding to the active OS circle. The transmitter is configured to transmit a signal using a transmission power based on the determined environmental scenario.

[0010] Certain aspects of the present disclosure provide an apparatus for wireless communication. The apparatus generally includes means for receiving a plurality of cross-polarization captures from a plurality of antenna arrays of the apparatus, means for detecting that the plurality of cross-polarization captures from the plurality of antenna arrays correspond to a first open space (OS) circle in an in-phase / quadrature (IQ) plane in a set of possible OS circles of the apparatus, means for assigning the first OS circle as an active OS circle of the apparatus and deactivating other possible OS circles in the set based on the detection, means for determining an environmental scenario corresponding to the active OS circle, and means for transmitting a signal using a transmission power based on the determined environmental scenario.

[0011] Certain aspects of the present disclosure provide a computer readable medium having instructions stored thereon for receiving a plurality of cross-polarization captures from a plurality of antenna arrays of a UE, detecting that the plurality of cross-polarization captures from the plurality of antenna arrays correspond to a first open space (OS) circle in an in-phase / quadrature (IQ) plane in a set of possible OS circles of the UE, assigning the first OS circle as an active OS circle of the UE and deactivating other possible OS circles in the set based on the detection, determining an environmental scenario corresponding to the active OS circle, and transmitting a signal using a transmission power based on the determined environmental scenario.

[0012] To the accomplishment of the foregoing and related ends, one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative aspects of the one or more aspects. These aspects are indicative, however, of but a few of the various ways in which the principles of various aspects can be employed and the description is intended to include all such aspects and their equivalents. BRIEF DESCRIPTION OF DRAWINGS

[0013] In order to enable a detailed understanding of the above-described features of the disclosure, a more particular description will be rendered by reference to specific aspects, some of which are illustrated in the drawings. It is appreciated that these drawings depict only a few aspects and are therefore not to be considered limiting of its scope, as the description can admit to other equally effective aspects.

[0014] Figure 1 FIG. 1 is a block diagram conceptually illustrating an example telecommunications system, in accordance with certain aspects of the present disclosure.

[0015] Figure 2 FIG. 2 is a block diagram conceptually illustrating a design of an example base station (BS) and an example user equipment (UE), in accordance with certain aspects of the present disclosure.

[0016] Figure 3 FIG. 3 is a block diagram showing an example transceiver front-end, in accordance with certain aspects of the present disclosure.

[0017] Figure 4A FIG. 4 illustrates millimeter wave (mmW) sensing by a UE, in accordance with certain aspects of the present disclosure.

[0018] Figure 4B FIG. 5 illustrates mmW sensing using cross-polarization (Xpol), in accordance with certain aspects of the present disclosure.

[0019] Figure 4C FIG. 6 illustrates mmW sensing using frequency-modulated continuous wave (FMCW) radar, in accordance with certain aspects of the present disclosure.

[0020] Figure 5 FIG. 7 illustrates an example fast Fourier transform (FFT) symbol value from Xpol detection, in accordance with certain aspects of the present disclosure.

[0021] Figure 6 FIG. 8 is an example plot of a cross-polarization ratio (K) in an in-phase / quadrature (IQ) plane for detecting objects in front of an antenna, in accordance with certain aspects of the present disclosure.

[0022] Figure 7 FIG. 9 is a flow diagram of an example operation of wireless communication, in accordance with certain aspects of the present disclosure.

[0023] Figure 8is an example plot of signal-to-noise ratio (SNR) in decibels (dB) for different scenarios with vertical and horizontal polarization components according to certain aspects of the present disclosure.

[0024] Figure 9 shows an example correlation between the standard deviation (σ K ) of K values and the average signal-to-noise ratio (SNR m ) of vertical and horizontal polarization components for different scenarios according to certain aspects of the present disclosure.

[0025] Figure 10 shows an example linear relationship between σ K and SNR m for different scenarios according to certain aspects of the present disclosure, where the line represents the boundary between open space (OS) and object detection region.

[0026] Figure 11 is a flowchart of determining parameters for OS based on σ K and SNR m according to certain aspects of the present disclosure.

[0027] Figure 12 is a flowchart of example operations of wireless communication based on antenna array codebook selection according to certain aspects of the present disclosure.

[0028] Figure 13 is a flowchart of example operations of wireless communication according to certain aspects of the present disclosure.

[0029] For ease of understanding, the same reference numbers have been used in the drawings to designate the same elements. Elements disclosed in one aspect are expected to be beneficially used in other aspects without specific recitation. DETAILED DESCRIPTION

[0030] Certain aspects of the present disclosure provide techniques and apparatuses for distinguishing whether an antenna of a user equipment (UE) is blocked by a cover (e.g., a protective cover of rubber or plastic) or by human tissue (e.g., a finger or a palm). The transmission power of uplink (UL) signals can be adjusted accordingly, with relatively higher transmission power for open space or a cover, and relatively lower transmission power for human tissue.

[0031] The following description provides examples, and is not limited to the scope, applicability or examples set forth in the claims. Changes can be made in the function and arrangement of elements discussed without departing from the scope of the disclosure. Various examples can omit, substitute, or add various procedures or components as appropriate. For instance, the methods described can be performed in an order different from that described, and various steps can be added, omitted, or combined. Also, features described with respect to some examples can be combined in some other examples. For example, any number of the aspects set forth herein can be implemented by, for example, an apparatus or a method. Also, the scope of the disclosure is intended to cover devices or methods that use other structures, functionality, or structures and functionality other than those explicitly set forth herein. It is to be understood that any aspect of the disclosure disclosed herein can be embodied by one or more elements of a claim. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects.

[0032] 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 a radio technology 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 a radio technology such as Global System for Mobile Communications (GSM). An OFDMA network can implement a radio technology 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 Universal Mobile Telecommunication System (UMTS).

[0033] New Radio (NR) is an emerging wireless communications technology under development for 5G Technology Forum (5GTF). 3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A) are releases of UMTS that use EUTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A and GSM are described in documents from the organization named “3rd Generation Partnership Project” (3GPP). cdma2000 and UMB are described in documents from an organization named “3rd Generation Partnership Project 2” (3GPP2). The techniques described herein can be used for the wireless networks and radio technologies mentioned above as well as other wireless networks and radio technologies. For clarity, while aspects can be described herein using terminology commonly associated with 3G and / or 4G wireless technologies, aspects of the present disclosure can be applied in other generation-based communication systems, such as 5G and later, including NR technologies.

[0034] NR access (e.g., 5G technology) can support various wireless communication services, such as Enhanced Mobile Broadband (eMBB) targeting wide bandwidth (e.g., 80 MHz or beyond), millimeter wave (mmW) targeting high carrier frequency (e.g., 25 GHz or beyond), massive machine type communications MTC (mMTC) targeting non-backward compatible MTC techniques, and / or mission critical communications targeting ultra-reliable low-latency communications (URLLC). These services can include latency and reliability requirements. These services can also have different transmission time intervals (TTI) to meet respective quality of service (QoS) requirements. In addition, these services can co-exist in the same subframe.

[0035] Example wireless communications system

[0036] Figure 1 An example wireless communication network 100 is shown in which various aspects of the present disclosure can be implemented. Wireless devices in the wireless network 100 can perform methods described further herein for determining an environmental scenario of an antenna (or antenna array) of a wireless device. 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 covering or a human grip) or is not blocked by an object (this case is referred to as “open space”).

[0037] As Figure 1As shown, the wireless network 100 can include a number of base stations (BSs) 110 and other network entities. A BS can be a station that communicates with user equipment (UEs). Each BS 110 can serve a particular geographical area and can be referred to as an eNodeB (eNB), a gNodeB (gNB), or another similar terminology, depending on the technology standard. In the example of FIG. 1, the BSs 110a, 110b and 110c can be macro BSs for the macro cells 102a, 102b and 102c, respectively. The BS 110x can be a pico BS for the pico cell 102x. The BSs 110y and 110z can be femto BSs for the femto cells 102y and 102z, respectively. A BS can support one or multiple (e.g., three) cells. The BSs 110 communicate with the UEs 120a, 120b, 120c and 120d over the communication links 132, 134 and 136 and can perform receive

[0038] In general, any number of wireless networks can be deployed in a given geographic area. Each wireless network can support a particular radio access technology (RAT) and can operate on one or more frequencies. A RAT can also be referred to as a radio technology, an air interface, etc. A frequency can also be referred to as a carrier, a subcarrier, a frequency channel, a tone, a subband, etc. Each frequency can support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks can be deployed.

[0039] A base station (BS) can be a station that communicates with user equipment (UEs). Each BS can serve a particular geographic area and can be referred to as an eNodeB (eNB), a gNodeB (gNB), or another similar terminology, depending on the technology standard. In the example of FIG. 1, the BSs 110a, 110b and 110c can be macro BSs for the macro cells 102a, 102b and 102c, respectively. The BS 110x can be a pico BS for the pico cell 102x. The BSs 110y and 110z can be femto BSs for the femto cells 102y and 102z, respectively. A BS can support one or multiple (e.g., three) cells. The BSs 110 communicate with the UEs 120a, 120b, 120c and 120d over the communication links 132, 134 and 136 and can perform receive Figure 1 In the example shown, the BSs 110a, 110b and 110c can be macro BSs for the macro cells 102a, 102b and 102c, respectively. The BS 110x can be a pico BS for the pico cell 102x. The BSs 110y and 110z can be femto BSs for the femto cells 102y and 102z, respectively. A BS can support one or multiple (e.g., three) cells.

[0040] Wireless communication network 100 can also include relay stations. A relay station is a station that receives a transmission of data and / or other information from an upstream station (e.g., a BS or a UE) and sends a transmission of the data and / or other information to a downstream station (e.g., a UE or a BS). A relay station can also be a UE that relays transmissions for other UEs. Figure 1 In the example shown, a relay station l lOr can communicate with BS 110a and a UE 120r in order to facilitate communication between BS 110a and UE 120r. A relay station can also be referred to as a relay BS, a relay station, etc.

[0041] Wireless network 100 can be a heterogeneous network that includes BSs of different types, e.g., macro BSs, pico BSs, femto BSs, relay stations, etc. These different types of BSs can have different transmit power levels, different coverage areas, and different impacts on interference in wireless network 100. For example, macro BSs can have a high transmit power level (e.g., 20 Watts) whereas pico BSs, femto BSs, and relay stations can have a lower transmit power level (e.g., 1 Watt).

[0042] Wireless communication network 100 can support synchronous or asynchronous operation. For synchronous operation, the BSs can have similar frame timing, and transmissions from different BSs can be approximately aligned in time. For asynchronous operation, the BSs can have different frame timing, and transmissions from different BSs can not be aligned in time. The techniques described herein can be used for both synchronous and asynchronous operation.

[0043] Network controller 130 can couple to a set of BSs and provide coordination and control for these BSs. Network controller 130 can be in communication with the BSs 110 via a backhaul. The BSs 110 can also communicate with one another (e.g., directly or indirectly) via wireless or wireline backhaul.

[0044] The UEs 120 (e.g., 120x, 120y, etc.) can be dispersed throughout the wireless network 100, and each UE can be stationary or mobile. A UE can also be referred to as a mobile station (MS), a terminal, an access terminal, a subscriber unit, a station, a client, 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, a camera, a gaming device, a netbook, a smartbook, an ultrabook, an electric

[0045] Certain wireless networks (e.g., LTE) utilize orthogonal frequency division multiplexing (OFDM) on the downlink and single-carrier frequency division multiplexing (SC-FDM) on the uplink. OFDM and SC-FDM partition 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. In general, modulation symbols are sent in the frequency domain with OFDM and in the time domain with SC-FDM. The spacing of the adjacent subcarriers can be fixed, and the total number of subcarriers (K) can be dependent on the system bandwidth. For example, the spacing of the subcarriers can be 15 kHz and the minimum resource allocation (called a “resource block” (RB)) can be 12 subcarriers (or 180 kHz). Consequently, the nominal fast fourier transform (FFT) size can be equal to 128, 256, 512, 1024 or 2048 for system bandwidth of 1.25, 2.5, 5, 10, or 20 megahertz (MHz), respectively. The system bandwidth can also be partitioned into subbands. For example, a subband can cover 1.08 MHz (i.e., 6 resource blocks), and there can be 1, 2, 4, 8, or 16 subbands for system bandwidth of 1.25, 2.5, 5, 10, or 20 MHz, respectively.

[0046] While aspects of the examples described herein can be associated with LTE technologies, aspects of the present disclosure can be applicable with other wireless communications systems, such as NR. NR can utilize OFDM with a cyclic prefix (CP) on the uplink and downlink and include support for half-duplex operation using time division duplex (TDD). Beamforming can be supported and beam direction can be dynamically configured. Multiple Input Multiple Output (MIMO) transmissions with precoding can also be supported. A MIMO configuration in the downlink (DL) can support up to 8 transmit antennas with multi-layer downlink transmission up to 8 streams and up to 2 streams per UE. Aggregation of multiple cells can be supported with up to 8 serving cells.

[0047] In some examples, access to an air interface can be scheduled, where a scheduling entity (e.g., a base station) allocates resources for communication among some or all devices and equipment 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 to use. That is, for scheduled communication, subordinate entities utilize resources allocated by the scheduling entity. A base station is not the only component that can function as a scheduling entity. In some examples, a UE can function as a scheduling entity and can schedule resources for one or more subordinate entities, such as one or more other UEs, and the other UEs can utilize the resources scheduled by the UE. In some examples, a UE can act as a scheduling entity in a peer-to-peer (P2P) network and / or in a mesh network. In a mesh network example, UEs can communicate directly with one another in addition to communicating with a scheduling entity.

[0048] exist Figure 1 In the diagram, a solid line with a double arrow indicates a desired transmission between the UE and the serving BS, which is the BS designated to serve the UE on the downlink and / or uplink. A dashed line with a double arrow indicates interference transmission between the UE and the BS.

[0049] Figure 2 The BS110 and UE 120 are shown (e.g.) Figure 1 The example components shown can be used to implement various aspects of this disclosure. For example, the antenna 252, transceiver (TX / RX) front-end circuitry 254, processors 258, 264, and / or controller / processor 280 of UE 120 can be used to perform the various techniques and methods described herein (e.g., Figure 7 Operation 700 Figure 12 Operation 1200 or Figure 13 Operation 1300).

[0050] At BS110, the transmit processor 220 can receive data from data source 212 and control information from controller / processor 240. The control information can be used for the Physical Broadcast Channel (PBCH), Physical Control Format Indicator Channel (PCFICH), Physical Hybrid ARQ Indicator Channel (PHICH), Physical Downlink Control Channel (PDCCH), Group Common PDCCH (GCPDCCH), etc. This data can also be used for the Physical Downlink Shared Channel (PDSCH), etc. The processor 220 can process (e.g., encode and symbol map) the data and control information to obtain data symbols and control symbols, respectively. The processor 220 can also generate reference symbols, for example, for the Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS), and Cell-Specific Reference Signal (CRS). The transmit (TX) multiple-input multiple-output (MIMO) processor 230 can perform spatial processing (e.g., precoding) on ​​the data symbols, control symbols, and / or reference symbols (if applicable) and can provide an output symbol stream to the transmit (TX) front-end circuits 232a to 232t. Each TX front-end circuit 232 can process its own output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each TX front-end circuit 232 can also process (e.g., convert to analog, amplify, filter, and up-convert) the output sample stream to obtain a downlink signal. The downlink signals from TX front-end circuits 232a to 232t can be transmitted via antennas 234a to 234t, respectively.

[0051] At the UE 120, the antennas 252a through 252r can receive the downlink signals from the BS 110 and can provide received signals to the receive (RX) front end circuitry 254a through 254r, respectively. Each RX front end circuitry 254 can condition (e.g., filter, amplify, downconvert, and digitize) a respective received signal to obtain input samples. Each RX front end circuitry 254 can further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. A MIMO detector 256 can obtain received symbols from all the RX front end circuitries 254a through 254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 258 can process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for the UE 120 to a data sink 260, and provide decoded control information to a controller / processor 280. A memory 282 can store data and program codes for the UE 120 and can interface with the controller / processor 280.

[0052] On the uplink, at the UE 120, a transmit processor 264 can receive and process data (e.g., for the physical uplink shared channel (PUSCH)) from a data source 262 and control information (e.g., for the physical uplink control channel (PUCCH)) from the controller / processor 280. The transmit processor 264 can also generate reference symbols for a reference signal (e.g., for the sounding reference signal (SRS)). The symbols from the transmit processor 264 can be precoded by a TX MIMO processor 266 if applicable, further processed by the RX front end circuitries 254a through 254r (e.g., for SC-FDM, etc.), and transmitted to the BS 110. At the BS 110, the uplink signals from the UE 120 can be received by the antennas 234, processed by the TX front end circuitries 232, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information transmitted by the UE 120. The receive processor 238 can provide the decoded data to a data sink 239 and the decoded control information to a controller / processor 240. A memory 242 can store data and program codes for the BS 110 and can interface with the controller / processor 240.

[0053] Controllers / processors 240 and 280 can direct the operation at BS 110 and UE 120, respectively. Processor 240 and / or other processors and modules at the BS 110 can perform or direct the execution of processes for the techniques described herein. Memories 242 and 282 can store data and program codes for BS 110 and UE 120, respectively. A scheduler 244 can schedule UEs for data transmission on the downlink and / or uplink.

[0054] Figure 3 is a block diagram of an example transceiver front-end 300 in accordance with certain aspects of the present disclosure, such as the TX / RX front-end circuitry 232, 254 in Figure 2 The transceiver front-end 300 includes at least one transmit (TX) path 302 (also referred to as a transmit chain) to transmit signals via one or more antennas and at least one receive (RX) path 304 (also referred to as a receive chain) to receive signals via an antenna. When the TX path 302 and the RX path 304 share an antenna 303, these paths can interface with the antenna via an RF interface 306, which can include any of a variety of suitable RF devices, such as duplexers, switches, duplexers, etc.

[0055] From a digital-to-analog converter (DAC) 308, which receives in-phase (I) or quadrature (Q) baseband analog signals, the TX path 302 can 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 can be included in a radio-frequency integrated circuit (RFIC), while the PA 316 can be included in the RFIC or external to 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 transmit local oscillator (LO) signal to convert the baseband signal of interest to a different frequency (e.g., up from baseband to RF). This frequency conversion process produces sum and difference frequencies between the LO frequency and the baseband signal frequency of interest. The sum and difference frequencies are referred to as beat frequencies. The beat frequencies are typically in the RF range, such that the signal output by the mixer 312 is typically an RF signal, which can be amplified by the DA 314 and / or the PA 316 before transmission by the antenna 303.

[0056] The RX path 304 can include a low noise amplifier (LNA) 322, a mixer 324, and a baseband filter (BBF) 326. The LNA 322, mixer 324, and BBF 326 can be included in a radio frequency integrated circuit (RFIC), which can or can not be the same RFIC that includes the TX path components. An RF signal received via the antenna 303 can be amplified by the LNA 322, and the mixer 324 mixes the amplified RF signal with a receive local oscillator (LO) signal to convert the RF signal of interest to a different baseband frequency (i.e., downconvert). The baseband signal output by the mixer 324 can be filtered by the BBF 326 before being converted to a digital I or Q signal for digital signal processing by an analog-to-digital converter (ADC) 328.

[0057] Some systems can employ a frequency synthesizer with a voltage controlled oscillator (VCO) to generate a stable, tunable LO with a particular tuning range. Thus, a transmit LO can be generated by the TX frequency synthesizer 318, which can be buffered or amplified by the amplifier 320 before being mixed with a baseband signal in the mixer 312. Similarly, a receive LO can be generated by the RX frequency synthesizer 330, which can be buffered or amplified by the amplifier 332 before being mixed with an RF signal in the mixer 324.

[0058] Example RF Exposure Assessment

[0059] RF exposure can be expressed in specific absorption rate (SAR), which measures the energy absorption per mass of human tissue, and the unit can be watts per kilogram (W / kg). Alternatively, RF exposure can be expressed in power density (PD), which measures the energy absorption per unit area, and the unit can be mW / cm2. SAR and PD can be used to assess RF exposure for different wireless communication technologies. 2 .

[0060] SAR can be used to assess RF exposure for transmission frequencies less than 6 GHz, which encompasses 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 for transmission frequencies higher than 10 GHz, which encompasses wireless communication technologies such as IEEE 802.11ad, 802.11ay, 5G, etc. Thus, different metrics can be used to assess RF exposure for different wireless communication technologies.

[0061] A wireless device (e.g., UE 120) can simultaneously transmit signals using multiple wireless communication technologies. For example, the wireless device can simultaneously transmit signals using a first wireless communication technology (e.g., 3G, 4G, 5G, etc.) that operates at or below 6 GHz and a second wireless communication technology (e.g., 5G in the 24-60 GHz band, IEEE 802.11 ad or 802.11 ay) that operates above 6 GHz. In certain aspects, the wireless device can simultaneously transmit signals using a first wireless communication technology (e.g., 3G, 4G, 5G, IEEE 802.11 ac in the 6 GHz band, etc.) in which RF exposure is measured according to SAR and a second wireless communication technology (e.g., 5G in the 24-60 GHz band, IEEE 802.11 ad, 802.11 ay, etc.) in which RF exposure is measured according to PD.

[0062] To evaluate RF exposure from transmissions using a first technology (e.g., 3G, 4G, 5G, IEEE 802.11 ac in the 6 GHz band, etc.), the wireless device can include a plurality of SAR profiles for the first technology stored in memory (e.g., Figure 2 memory 282 of the apparatus 200). Each of the SAR profiles can correspond to a respective one of a plurality of transmission scenarios supported by the wireless device for the first technology. The transmission scenarios can correspond to various combinations of antennas (e.g., Figure 2 antennas 252a-252r of the apparatus 200 or Figure 3 antennas 303 of the apparatus 300), frequency bands, channels, and / or body positions, as discussed further below.

[0063] The SAR profile (also referred to as a SAR map) for each transmission scenario can be generated based on measurements (e.g., E-field measurements) performed in a test laboratory using a human body model. After the SAR profiles are generated, the SAR profiles can be stored in memory to enable a processor (e.g., Figure 2 processor 266 of the apparatus 200) to evaluate RF exposure in real-time. Each SAR profile includes a set of SAR values, where each SAR value can correspond to a different location (e.g., on the human body model). Each SAR value can include an average SAR value over a 1 g or 10 g mass at the respective location.

[0064] The SAR values in each SAR profile correspond to a particular transmission power level (e.g., the transmission power level at which the SAR values were measured in the test laboratory). Since SAR scales with the transmission power level, the processor can scale the SAR profile for any transmission power level by multiplying each SAR value in the SAR profile by a transmission power scaler:

[0065]

[0066] where Tx c is the current transmission power level for the respective transmission scenario, and Tx SAR is the transmission power level corresponding to the SAR value in the stored SAR profile (e.g., the transmission power level at which the SAR value was measured in the test lab).

[0067] As described above, a wireless device can support multiple transmission scenarios for a first technology. In certain aspects, a transmission scenario can be specified by a set of parameters. The set of parameters can include one or more of an antenna parameter indicating one or more antennas (i.e., active antennas) used for transmission, a frequency band parameter indicating one or more frequency bands (i.e., active frequency bands) used for transmission, a channel parameter indicating one or more channels (i.e., active channels) used for transmission, a body position parameter indicating a position of the wireless device relative to a body position of a user (head, torso, away from the body, etc.), and / or other parameters. In cases where a wireless device supports a large number of transmission scenarios, performing measurements in a test environment (e.g., a test lab) for each transmission scenario can be very time consuming and expensive. To reduce test time, measurements can be performed for a subset of the transmission scenarios to generate SAR profiles for the subset of transmission scenarios. In this example, a SAR profile for each of the remaining transmission scenarios can be generated by combining two or more SAR profiles for the subset of transmission scenarios, as discussed further below.

[0068] For example, SAR measurements can be performed for each of the antennas to generate a SAR profile for each of the antennas. In this example, a SAR profile for a transmission scenario in which two or more antennas are active can be generated by combining SAR profiles for the two or more active antennas.

[0069] In another example, SAR measurements can be performed for each of a plurality of frequency bands to generate a SAR profile for each of the plurality of frequency bands. In this example, a SAR profile for a transmission scenario in which two or more frequency bands are active can be generated by combining SAR profiles for the two or more active frequency bands.

[0070] In certain aspects, a SAR profile can be normalized with respect to a SAR limit by dividing each SAR value in the SAR profile by the SAR limit. In this case, when a normalized SAR value is greater than 1, the normalized SAR value exceeds the SAR limit, and when a normalized SAR value is less than 1, the normalized SAR value is below the SAR limit. In these aspects, each of the SAR profiles stored in the memory can be normalized with respect to the SAR limit.

[0071] In certain aspects, the normalized SAR distribution for a transmission scenario can be generated by combining two or more normalized SAR distributions. For example, the normalized SAR distribution for a transmission scenario in which two or more antennas are active can be generated by combining the normalized SAR distributions for the two or more active antennas. For cases in which different transmission power levels are used for the active antennas, the normalized SAR distribution for each active antenna can be scaled by the respective transmission power level before combining the normalized SAR distributions for the active antennas. The normalized SAR distribution for simultaneous transmission from multiple active antennas can be given by:

[0072]

[0073] where SAR lim is the SAR limit, SAR norm_combined is the combined normalized SAR distribution for simultaneous transmission from active antennas, i is an index for the active antennas, SAR i is the SAR distribution for the i-th active antenna, Tx i is the transmission power level for the i-th active antenna, Tx SARi is the transmission power level for the SAR distribution of the i-th active antenna, and K is the number of active antennas.

[0074] Equation (2) can be rewritten as follows:

[0075]

[0076] where SAR norm_i is the normalized SAR distribution for the i-th active antenna. In the case of simultaneous transmission using multiple active antennas 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 computing the square of the sum, as shown by the following equation:

[0077]

[0078] In another example, normalized SAR distributions for different frequency bands can be stored in the memory. In this example, a normalized SAR distribution for a transmission scenario in which two or more frequency bands are active can be generated by combining normalized SAR distributions for the two or more active frequency bands. For cases in which the transmission power level is different for the active frequency bands, the normalized SAR distribution for each of the active frequency bands can be scaled by the respective transmission power level before combining the normalized SAR distributions for the active frequency bands. In this example, the combined SAR distribution can also be computed using equation (3a), in which i is an index of an active frequency band, SAR norm_i is the normalized SAR distribution for the i-th active frequency band, Tx i is the transmission power level for the i-th active frequency band, and Tx SARi is the transmission power level for the normalized SAR distribution of the i-th active frequency band.

[0079] To evaluate RF exposure from transmissions using a second technology (e.g., 5G in the 24-60 GHz band, IEEE 802.11ad, 802.11ay, etc.), the wireless device can include a plurality of PD distributions for the second technology stored in the memory (e.g., Figure 2 memory 282) of the wireless device 100. Each of the PD distributions can correspond to a respective one of a plurality of transmission scenarios supported by the wireless device for the second technology. The transmission scenarios can correspond to various combinations of antennas (e.g., Figure 2 antennas 252a-252r of the wireless device 100 or Figure 3 antennas 303 of the wireless device 100), frequency bands, channels, and / or body positions.

[0080] The PD distribution (also referred to as a PD map) for each transmission scenario can be generated based on measurements (e.g., E-field measurements) performed in a test laboratory using a human body model. After the PD distributions are generated, the PD distributions can be stored in the memory to enable the processor (e.g., Figure 2 processor 266) of the wireless device 100 to evaluate 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 the human body model).

[0081] The PD values in each PD distribution correspond to a particular transmission power level (e.g., the transmission power level at which the PD values were measured in the test laboratory). Since the PD scales with the transmission power level, the processor can scale the PD distribution for any transmission power level by multiplying each PD value in the PD distribution by the following transmission power scaler:

[0082]

[0083] where T c is the current transmission power level for the corresponding transmission scenario, and T XPD is the transmission power level corresponding to the PD value in the PD distribution (e.g., the transmission power level at which the PD value was measured in the test lab).

[0084] As described above, the wireless device can support multiple transmission scenarios for the second technology. In certain aspects, a transmission scenario can be specified by a set of parameters. The set of parameters can include one or more of an antenna parameter indicating one or more antennas (i.e., active antennas) used for transmission, a frequency band parameter indicating one or more frequency bands (i.e., active frequency bands) used for transmission, a channel parameter indicating one or more channels (i.e., active channels) used for transmission, a body position parameter indicating a position of the wireless device relative to a body position of a user (head, torso, away from the body, etc.), and / or other parameters. In cases where the wireless device supports a large number of transmission scenarios, it can be very time consuming and expensive to perform measurements in a test setting (e.g., a test lab) for each transmission scenario. To reduce testing time, measurements can be performed for a subset of the transmission scenarios to generate PD distributions for the subset of transmission scenarios. In this example, a PD distribution for each of the remaining transmission scenarios can be generated by combining two or more PD distributions for the subset of transmission scenarios, as discussed further below.

[0085] For example, PD measurements can be performed for each antenna to generate a PD distribution for each of the antennas. In this example, a PD distribution for a transmission scenario in which two or more antennas are active can be generated by combining PD distributions for the two or more active antennas.

[0086] In another example, PD measurements can be performed for each of a 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 frequency bands are active can be generated by combining PD distributions for the two or more active frequency bands.

[0087] In certain aspects, a PD distribution can be normalized with respect to a PD limit by dividing each PD value in the PD distribution by the PD limit. In this case, when a normalized PD value is greater than 1, the normalized PD value exceeds the PD limit, and when a normalized PD value is less than 1, the normalized PD value is below the PD limit. In these aspects, each of the PD distributions stored in the memory can be normalized with respect to the PD limit.

[0088] In certain aspects, the normalized PD distribution for a transmission scenario can be generated by combining two or more normalized PD distributions. For example, the normalized PD distribution for a transmission scenario in which two or more antennas are active can be generated by combining the normalized PD distributions for the two or more active antennas. For cases in which different transmission power levels are used for active antennas, the normalized PD distribution for each active antenna can be scaled by the respective transmission power level before combining the normalized PD distributions for the active antennas. The normalized PD distribution for simultaneous transmission from multiple active antennas can be given by:

[0089]

[0090] where PD lim is the PD limit, PD norm_combined is the combined normalized PD distribution for simultaneous transmission from active antennas, i is an index for active antennas, PD i is the PD distribution for the i-th active antenna, Tx i is the transmission power level for the i-th active antenna, T XPDi is the transmission power level for the PD distribution of the i-th active antenna, and L is the number of active antennas.

[0091] Equation (5) can be rewritten as follows:

[0092]

[0093] where PD norm_i is the normalized PD distribution for the i-th active antenna. In the case of simultaneous transmission using multiple active antennas 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 computing the square of the sum, as shown by the following equation:

[0094]

[0095] In another example, normalized PD distributions for different frequency bands can be stored in memory. In this example, a normalized PD distribution for a transmission scenario in which two or more frequency bands are active can be generated by combining normalized PD distributions for the two or more active frequency bands. For cases in which the transmission power level is different for the active frequency bands, the normalized SAR distribution for each of the active frequency bands can be scaled by the respective transmission power level before combining the normalized PD distributions for the active frequency bands. In this example, the combined PD distribution can also be computed using Equation (6a), in which i is an index of an active frequency band, PD norm i is the normalized PD distribution for the i-th active frequency band, Tx i is the transmission power level for the i-th active frequency band, and T XPDi is the normalized PD distribution for the i-th active frequency band scaled by the transmission power level for the i-th active frequency band.

[0096] Example method for distinguishing between a cover and a human grasp

[0097] As noted above, in wireless communications, there are maximum permissible exposure (MPE) limits from international regulatory bodies including the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and the Federal Communications Commission (FCC) that specify the maximum power or energy density (in W / cm 2 or J / cm 2 ) of an electromagnetic source that is considered safe. In some cases, the MPE limit can be translated into a constraint related to the maximum transmission power of one or more devices (e.g., depending on the implementation of each of the devices), and thus uplink (UL) signals transmitted by the devices can be limited due to MPE compliance.

[0098] Some UEs can include a sensor (e.g., a millimeter wave (mmW) sensor) that allows for a higher UL transmission power level if the sensor output shows that no object blocking the UE’s antenna is detected, thus potentially boosting the UL throughput for transmissions at such higher power level. For example, Figure 4A mmW sensing by a UE 120 using such an object detection sensor is shown. In Figure 4A , the UE 120 includes at least one antenna array 400 with multiple antennas 402a-d (collectively referred to herein as “antennas 402”). To detect an object 404 (in Figure 4B and Figure 4C ​In either a near-field (NF) or open space (OS) case, UE 120 can output a signal (e.g., a continuous wave (CW), an out-of-band signal) with a particular detection angle 406 from one of the antennas 402 in the array 400 (e.g., from antenna 402a), and another antenna in the array (e.g., antenna 402d) can receive a signal reflected off the surface of a nearby object 404 (such as a protective covering or a human hand or finger). With the reflected signal, UE 120 can utilize a cross-polarization (Xpol) with two polarized receive paths (one for a horizontally polarized component (labeled “H-pol”) and the other for a vertically polarized component (labeled “V-pol”)) as shown in Figure 4B circuit 420) to determine a cross-polarization ratio (K = k V / k H ) and detect whether the object 404 is present. Additionally or alternatively, UE 120 can use frequency-modulated continuous wave (FMCW) radar for object detection as shown in Figure 4C an example sweep and circuit 460. As shown in Figure 4A Xpol can have an object detection radius 408 of from 0 to about 4 cm from UE 120, while FMCW radar can have an object detection radius of from about 4 cm to about 60 cm from the UE.

[0099] As described above, Figure 4B shows mmW sensing using cross-polarization (Xpol) to detect an object 404 near a UE or to detect an OS condition in accordance with certain aspects of the present disclosure. In Figure 4B antenna array 400 includes four antennas 402, although any suitable number of antennas can be used. In circuit 420, a transmit path (e.g., transmit path 302) includes a frequency synthesizer (e.g., TX frequency synthesizer 318) and an amplifier 421. The frequency synthesizer is used to generate a CW signal with a frequency (f CW ) that is out-of-band, e.g., between a first component carrier frequency band (CCI) and a second component carrier frequency band (CC2). In this example, f CW is 28 GHz. Amplifier 421 can amplify the CW signal and drive antenna 402a to wirelessly transmit the signal (e.g., at a particular detection angle 406).

[0100] If an object 404 is present near the UE, the surface of the object can reflect the transmitted signal, and another antenna in the antenna array 400 (e.g., antenna 402d) can receive the signal reflected from the surface of the object. For Xpol detection, the receive path (e.g., receive path 304) can include two polarized receive paths (one for the horizontal polarization component (labeled “H-pol”) and the other for the vertical polarization component (labeled “V-pol”) in electrical diagram 420). The H-pol receive path includes an amplifier (e.g., low noise amplifier 332 H ), a mixer 324 H , a filter (e.g., baseband filter 326 H ), and an ADC 328 H . Similarly, the V-pol receive path includes an amplifier (e.g., low noise amplifier 332 V ), a mixer 324 V , a filter (e.g., baseband filter 326 V ), and an ADC 328 V . A frequency synthesizer (e.g., RX frequency synthesizer 330) can generate a local oscillator (LO) signal (e.g., with a frequency of 28.001 GHz, an offset of 100 MHz from the transmitted signal) as an input to each of the H-pol and V-pol mixers 324 H , 324 V .These receive chain components in Figure 4B may work as described above with reference to Figure 3 to amplify the received RF signal, mix the amplified RF signal with the LO signal to downconvert the signal, filter the mixed signal to focus on a baseband signal, and digitize the baseband signal.

[0101] The H-pol and V-pol digitized signals from the ADCs can be conveyed to a processor 422, which can be implemented by a digital signal processor (DSP) or any other suitable processing system. The processor 422 can include a fast Fourier transform (FFT) module 424 and a frequency domain in-phase / quadrature (FD-IQ) module 426. The FFT module 424 can be used to convert the time domain digitized signals into frequency domain data, which can yield a maximum H-pol FFT value (k H ) and a maximum V-pol FFT value (k V ), as explained below with reference to Figure 5 . Using the frequency domain data, the FD-IQ module 426 can be used to plot a cross-polarization ratio (K = k V / k H ​​), as shown by graph 430. Open space (i.e., no objects nearby) can have a different position in the I / Q plane than various objects, and in this way, Xpol can be used to determine whether an object is present or not.

[0102] As described above, Figure 4C mmW sensing using FMCW radar to detect objects 404 near a UE or to detect an OS case is shown in accordance with certain aspects of the present disclosure. In Figure 4C Antenna array 400 includes four antennas 402, although any suitable number of antennas can be used. In circuit diagram 460, a transmit path (e.g., transmit path 302) includes DAC 308, baseband filter 310, mixer 312, and amplifier 421, which can represent DA 314 and / or PA 316. Frequency synthesizer 462 can be used to generate an LO signal for input to mixer 312. Frequency synthesizer 462 in combination with other components of the transmit path can be used to generate a sweep (e.g., from 25 to 29 GHz) in a wireless transmit signal output from antenna 402a, which can include CC1 and CC2 bands as shown.

[0103] If an object 404 is present near the UE, the surface of the object can reflect the transmitted signal, and another antenna in antenna array 400 (e.g., antenna 402d) can receive the signal reflected from the surface of the object. For FMCW radar detection, a receive path (e.g., receive path 304) can include low noise amplifier 332, mixer 324, baseband filter 326, and ADC 328. Figure 4C These receive path components in circuit diagram 460 can operate as described above with respect to Figure 3 amplify the received RF signal, mix the amplified RF signal with an LO signal from frequency synthesizer 462 to downconvert the signal, filter the mixed signal to focus on a baseband signal, and digitize the baseband signal. The FMCW digitized signal from ADC 328 can be communicated to processor 464, which can be implemented by a DSP or any other suitable processing system. Processor 464 can process the FMCW digitized signal to detect an object or an open space case.

[0104] Figure 5 Example FFT symbol values from Xpol detection are shown in accordance with 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 values 610 indicates k H and the maximum value of the vertical polarization FFT values 620 indicates k VThe cross-polarization ratio (K) is given by K = k V / k H is determined.

[0105] The complex value of K(I + jQ) provides an indication of the presence of an object in front of the antenna. k V / k H The division (which can be implemented as k V k H * ) can eliminate calibration of transmit gain / phase randomness during each measurement. Figure 6 is an example plot 600 of multiple samples of K in the in-phase / quadrature (IQ) plane for two different scenarios: open space and finger grip (or protective cover).

[0106] The standard deviation (σ K ) of K over K consecutive measurements over a period of time provides a measure of the stability of an object in front of the antenna. In other words, a relatively large σ K implies lower object stability (i.e., more object motion), while a relatively small σ K indicates higher stability (i.e., less object motion). Open space (i.e., no reflector) provides a relatively small σ K . A human finger or hand in front of the antenna provides a relatively large σ K , but a finger gripping the UE provides a relatively small σ K , because the finger does not move much as part of the grip. Similarly to the finger and grip, a protective cover (e.g., made of plastic and / or glass) also provides a small σ K , making it difficult to distinguish between a protective cover and a human grip using σ K alone. For example, as shown in the example plot 600 of Figure 6 , the σ K for open space can be similar to the σ K for a protective cover (or finger grip).

[0107] When the antenna is blocked by a protective cover, the UE can use a higher transmission power, but, as noted above, due to MPE limitations, a lower transmission power should be used when the antenna is blocked by a finger or other human tissue. Thus, techniques and apparatuses are needed for distinguishing between a protective cover and a human grip by an object detection sensor of the UE.

[0108] In addition, different protective covers can provide different cross-polarization ratio mean values {mean(K)} in the IQ plane. Algorithms used to determine transmission power can periodically adjust the open space parameters for the UE, which can also make it more difficult to distinguish between protective covers and finger grips when combined with different K mean values for different protective covers.

[0109] Certain aspects of the present disclosure provide techniques and apparatus for using at least two different types of parameters to distinguish whether a UE's antenna is blocked by a cover (e.g., a protective rubber or plastic covering) or by human tissue (e.g., a finger or palm), as described in more detail below.

[0110] Figure 7 FIG. 7 is a flow chart illustrating example operations 700 for wireless communication, in accordance with certain aspects of the present disclosure. The operations 700 can be performed, for example, by a wireless device (e.g., a UE 120) as described herein, and more specifically by a receiver, a processor, and a transmitter of the wireless device. Figure 1

[0111] The operations 700 can begin, at block 701, with the wireless device transmitting a first signal (e.g., with the TX front-end circuitry 254a-254r or transmit path 302 of the UE 120), and at block 702, receiving a plurality of signals (e.g., reflections of the transmitted first signal) based on the transmitted first signal (e.g., with the RX front-end circuitry 254a-254r or receive path 304 of the UE 120). 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., with the receive processor 258, the control / processor 280, and / or the transmit processor 264 or with 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., with the receive processor 258, the control / processor 280, and / or the transmit processor 264 or with the processor 422 of the UE 120). At block 708, the wireless device transmits a second signal using a transmission power based on the determined environmental scenario (e.g., with the TX front-end circuitry 254a-254r or transmit path 302 of the UE 120). The operations 700 will be described in more detail below, and are illustrated in the various figures.

[0112] As described above, σ K may not be sufficient to distinguish between protective coverings and human grips. Accordingly, certain aspects of the present disclosure provide another dimension of information in addition to σ K For certain aspects, this additional information can be determined from the FFT data already provided by the two polarized receive paths.

[0113] ​For example, empirical studies show that the signal-to-noise ratio (SNR) of FFTs from H-pol and V-pol fluctuates with different object types. The SNR of the vertical polarization component (SNRV) can be expressed as SNR V =10*log 10 (k V / σ 2 FFTV ), where σ 2 FFTV This is the variance of the vertical polarization FFT value (e.g., FFT value 520). The SNR of the horizontal polarization component (SNR...) H This can be represented as SNR. H =10*log 10 (k H / σ 2 FFTH ), where σ 2 FFTH This is the variance of the horizontally polarized FFT values ​​(e.g., FFT value 510). The average SNR of these two SNRs (SNR... m This can be represented as SNR. m =SNR V -(SNR H -SNR V A processor that computes the FFT value (e.g., processor 422) can compute the value with respect to k. H or k V The noise power of multiple bins adjacent to the peak (e.g., 20 adjacent bins, 10 bins on each side of the peak). In some respects, the processor can remove or otherwise effectively ignore bins with spurs.

[0114] Electromagnetic (EM) simulations show that the near-field coupling electric field varies with the dielectric material simulating a human finger. The assumption for the observed SNR fluctuations is that the coupled signal power fluctuates relative to a fixed receiver noise substrate (e.g., according to kTBFG, where k is the Boltzmann constant, T is the absolute temperature, F is the noise figure, B is the receiver bandwidth, and G is the gain) and is material-type dependent due to the material's reflection coefficient.

[0115] Figure 8 Figure 800 shows example SNR in decibels (dB) of the vertical and horizontal polarization components for different scenarios, including open space (OS), grip, and protective cover. Therefore, with this additional information, the same σ is produced. K Different environmental scenarios can also be viewed by checking SNR. m To distinguish them.

[0116] Figure 9An example plot 900 of K for different scenarios in the IQ plane is shown. In the IQ plot 900, a normal human finger pressed on the UE has a relatively very large σ K , as shown by the distribution of K values. In contrast, an open space and a human palm pressed on the UE have similar relatively small σ K , as shown by the distribution of K values. In contrast, an open space and a human palm pressed on the UE have similar relatively small σ K . Thus, considering only σ K , it can be difficult to distinguish between open space, protective cover, or human tissue cases.

[0117] According to Figure 9 Also shown is a plot 950 illustrating an example correlation between σ K and SNR m for the same scenarios presented in the IQ plot 900 for certain aspects of the present disclosure. Using regression or any of various other suitable techniques, a linear equation can be found to separate scenarios that can be classified as OS (e.g., OS or protective cover) and scenarios that can be classified as object detection (e.g., presence of human tissue) in order to determine transmission power. The line 952 represented by this linear equation in plot 950 can be considered a boundary that separates two regions: an OS region and an object detection region. The threshold standard deviation (σ TH ) of this OS / detection boundary line 952 can be represented as σ TH = m * SNR m + c, where m is the slope of the line and c is the σ K offset.

[0118] Figure 10 is a plot 1000 illustrating an example linear relationship between σ K and SNR m for different scenarios (e.g., different materials) according to certain aspects of the present disclosure, where a line 1002 with the equation σ TH = m * SNR m + c represents a boundary between an open space (OS) and an object detection region. Note how air, a rubber protective cover, and a plastic phone back shell are in the OS region, while a pressed horizontal human finger, a pressed human palm, a pressed normal human finger, and a pressed vertical human finger are in the detection region. The linear equation can be frequency or band dependent. Additionally or alternatively, the linear equation can be dependent on a particular UE, varying between types, brands, and models.

[0119] Figure 11 is a plot 1100 illustrating σ K and SNR mA flowchart 1100 determines parameters for an OS. The parameters for the OS can include a radius (R OS ) and a center (C OS ) of the OS. As shown in flowchart 1100, if σ K < σ TH (indicating an OS region), then the OS parameters can be updated, where R OS = 3 * σ K , and where C OS = mean(K). Otherwise, the OS parameters are not updated, and more samples are captured. More specifically, at block 1102, a sample (e.g., an Xpol sample) is captured, and at block 1104, an FFT is performed on the captured sample to convert the sampled data from the time domain to the frequency domain. As described above, from the FFT, σ K may be determined at block 1106, and SNR m may be determined at block 1108. At block 1110, the variables (e.g., m and c) of the linear equation for the boundary (e.g., line 952 or line 1002) between the open space and the object detection region can be determined (e.g., read from memory, such as from memory 282). At block 1112, σ m may be calculated using the variables of the linear equation and SNR TH . If it is determined at block 1114 that σ K < σ TH (indicating an OS region), then the OS parameters are updated at block 1116, where R OS = 3 * σ K , and where C OS = mean(K). Otherwise, if it is determined at block 1114 that σ K ≥ σ TH , then the OS parameters are not updated, and more samples are captured at block 1102.

[0120] As described above, certain aspects of the present disclosure are directed to a method of 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.

[0121] According to certain aspects, the received plurality of signals includes a vertically polarized component signal and a horizontally polarized component signal. For certain aspects, the at least two different types of parameters include a statistic of a cross-polarization ratio between the vertically polarized component signal and the horizontally polarized component signal. For example, the statistic of the cross-polarization ratio can be a standard deviation of the cross-polarization ratio. For certain aspects, the at least two different types of parameters also include a signal-to-noise ratio statistic based on the vertically polarized component signal and the horizontally polarized component signal. For example, the statistic of the signal-to-noise ratio can be a mean of the signal-to-noise ratio computed based on a variance of the vertically polarized component signal and a variance of the horizontally polarized component signal.

[0122] According to certain aspects, the at least two different types of parameters include a signal-to-noise ratio statistic based on the vertically polarized component signal and the horizontally polarized component signal.

[0123] According to certain aspects, receiving the plurality of 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.

[0124] 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.

[0125] According to certain aspects, determining the environmental scenario entails distinguishing whether the antenna of the UE is obstructed by a cover or by human tissue. For example, the cover can include a protective case for the UE.

[0126] According to certain aspects, determining the environmental scenario includes determining a center and a radius of an open space from the antenna of the UE.

[0127] 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 the 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, a relatively lower transmission power can be used to transmit a signal if one of the at least two types of parameters is above the line, and a relatively higher transmission power can be used to transmit a signal if one of the at least two types of parameters is not above the line. For certain aspects, parameters (e.g., a slope and an offset) of the line can be stored in a memory.

[0128] According to certain aspects, determining the environmental scenario includes determining a boundary based on a relationship between the 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, a relatively lower transmission power can be used to transmit the signal if one of the at least two types of parameters is on the first side of the boundary, and a relatively higher transmission power can be used to transmit the signal if one of the at least two types of parameters is on the second side of the boundary.

[0129] According to certain aspects, determining the environmental scenario includes determining a material of a protective cover covering the UE. For certain aspects, the received plurality of signals includes a vertically polarized component signal and a horizontally polarized component signal, and the at least two different types of parameters include a statistic 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 cover covering the UE can be based at least in part on the statistic of the cross-polarization ratio. For example, the statistic can be a standard deviation of the cross-polarization ratio.

[0130] Example automatic cover detection

[0131] As mentioned above, millimeter wave (mmWave) transmissions present a potential safety hazard because such transmissions can cause localized heating of the skin or the surface of the eye. To protect the public from such harm, government regulators set RF exposure limits (e.g., in terms of maximum power per square centimeter of area). For mmWave, this limit is referred to as the maximum permissible exposure (MPE) limit. For example, the United States Federal Communications Commission (FCC) has set an MPE limit for all transmissions at frequencies greater than 3 GHz. For example, for transmissions between 30 and 300 GHz, the FCC MPE limit is set to 1 mW / cm2. The MPE limit tightens the link budget for 5G mmWave uplink (UL) transmissions. 2 The MPE limit tightens the link budget for 5G mmWave uplink (UL) transmissions.

[0132] One solution is to use a proximity sensor that determines whether a human body is in the vicinity of the mmWave module. When the proximity sensor indicates an open space (OS), the UE can transmit at a higher power, but if the sensor indicates the presence of an object, the UE can back off its UL transmission power to remain compliant with the MPE limit. One drawback of many proximity sensors is that they cannot distinguish between a human body and other objects. Thus, when an end user installs a protective cover on the UE, the cover can trigger a persistent detection such that the proximity sensor is not available. Thus, a mechanism to sense through the protective cover is desired.

[0133] As described above, cross-polarization (Xpol) sensors can rely on near-field coupling characteristics between transmit and receive antenna elements within a mmWave antenna array to detect the presence of objects near the antenna array. With Xpol, a transmitter can transmit a single tone (e.g., at a mmWave frequency), and two receivers can receive the transmitted tone back. The two receivers can be attached to antenna ports with different polarizations (e.g., vertical and horizontal polarizations). The phase and magnitude of the ratio (K = k v / k H ) of the two received signals is used as a signature to identify an OS from an object.

[0134] With the Xpol algorithm, the OS signature can be defined as an OS circle, the center and radius of which are plotted on the in-phase / quadrature (IQ) plane, e.g., as described herein with reference to FIG. 3. The OS signature for each antenna array (at each frequency or each band) can be characterized or calibrated per device. Once this OS circle is established for a given antenna array, the Xpol algorithm can detect objects by classifying captures that lie outside the OS circle in the IQ plane as detections of objects and classifying captures that lie inside the OS circle as open space. The OS circle can be characterized or generated for various states of the antenna array and UE, such as a state when the UE is uncovered and multiple states corresponding to various cases or coverings. For example, an OS circle can be characterized for a given antenna array when the UE is uncovered, while another OS circle can be characterized for that antenna array when the UE is covered by a particular sleeve or covering. Figure 6

[0135] A single Xpol sensing can have difficulty distinguishing between body parts and other objects, as is often the case for most other sensors as well. Thus, when an end user installs a protective covering on a UE (e.g., a smartphone), the covering can trigger a persistent detection, which is problematic. One potential solution to this problem is to have multiple active OS circles. For example, one OS circle can be associated with the bare (i.e., uncovered) UE, while another OS circle can correspond to the characterized covering. In this case, the Xpol algorithm can classify a capture as an OS if the capture lies in either of these OS circles. A problem with this approach is that it is possible to find a particular finger touch location on top of the bare UE, which causes the capture to be incorrectly located in the OS circle of the covering. This finger touch location is likely to be misdetected on the bare UE because the capture will be interpreted as an OS on the covering.

[0136] ​Certain aspects of the present disclosure provide Xpol-based algorithms and sensors that support multiple OS circles, but only allow one of these OS circles to be active at a time. In this way, when the algorithm determines that the UE is bare, the algorithm deactivates the OS circles for all covers, and when the algorithm determines that a particular cover is installed, the algorithm deactivates the OS circles for the bare UE and any other covers (except for the OS circle for the installed cover). Thus, certain aspects of the present disclosure relate to Xpol algorithms that determine when a cover is installed and which cover is installed. This Xpol algorithm relies on the very low likelihood that a bare UE is held in such a way that the particular holding scenario looks like the OS for a cover across multiple antenna arrays. For certain aspects, the Xpol algorithm can determine that a cover is installed by observing Xpol captures across multiple antenna arrays. When an OS corresponding to a given cover is detected across multiple antenna arrays, the algorithm designates the OS circle for that given cover as the only active OS circle. Similarly, when a terminal user removes a cover, the algorithm can eventually observe an OS for the bare UE detected across multiple antenna arrays, and thus, the algorithm can reassign the OS circle for the bare UE as the only active OS circle.

[0137] As shown in Table 1, the nominal values for the OS circles can not be the same for a given environmental situation (e.g., a particular cover) observed by different antenna arrays. In Table 1, the rows correspond to antenna arrays in the UE, and the columns correspond to environmental situations. The algorithms disclosed herein can select a single column in Table 1 at a time, rather than selecting a single OS at a time.

[0138] Environmental Case 1 Environmental Case 2 Environmental Case 3 Environmental Case 4 Antenna Array 1 OS 11 OS 12 OS 13 OS 14 Antenna Array 2 OS 21 OS 22 OS 23 OS 24 Antenna Array 3 OS 31 OS 32 OS 33 OS 34 Antenna Array 4 OS 41 OS 42 OS 43 OS 44

[0139] Table 1

[0140] Figure 13 is a flowchart of example operations 1300 for wireless communication in accordance with certain aspects of the present disclosure. The operations 1300 can be performed, for example, by a wireless device (e.g., the UE 120) and more specifically by a receiver, a processor, and a transmitter of the wireless device. Figure 1

[0141] ​Operations 1300 can begin, at block 1301, with a wireless device transmitting at least one test signal (e.g., with TX front-end circuitry 254a-254r or transmit path 302 of UE 120) and, at block 1302, receiving a plurality of cross-polarization captures from a plurality of antenna arrays (e.g., with RX front-end circuitry 254a-254r or receive path 304 of UE 120). In some aspects, the received plurality of cross-polarization captures can be indicative of reflections of the transmitted test signal. At block 1304, the wireless device can detect that the plurality of cross-polarization captures from the plurality of antenna arrays correspond to a first open space (OS) circle in an in-phase / quadrature (IQ) plane of a set of possible OS circles for the wireless device. Based on the detection at block 1304, the wireless device can assign, at block 1306, the first OS circle as an active OS circle for the wireless device. Based on the detection at block 1304, the wireless device can also deactivate (e.g., ignore) other possible OS circles in the set. At block 1308, the wireless device can determine an environmental scenario corresponding to the active OS circle. At block 1310, the wireless device can transmit a signal using a transmission power based on the determined environmental scenario (e.g., with TX front-end circuitry 254a-254r or transmit path 302 of UE 120).

[0142] In certain aspects, as the first OS circle can be associated with a particular state of the wireless device (e.g., covered by a particular cover / sleeve or uncovered), the wireless device can update the active OS circle to a second OS circle in the set of possible OS circles and associated with another state of the wireless device, e.g., as the wireless device is covered by a different cover / sleeve or a change in coverage. With respect to operations 1300, the wireless device can transmit another test signal and receive another plurality of cross-polarization captures from the plurality of antenna arrays of the wireless device. The wireless device can detect that the other plurality of cross-polarization captures from the plurality of antenna arrays correspond to a second OS circle in the IQ plane of the set of possible OS circles, the second OS circle being different from the first OS circle. The wireless device can assign the second OS circle as the active OS circle for the wireless device and deactivate other possible OS circles in the set, including the first OS circle, based on detecting the correspondence to the second OS circle. As an example, the first OS circle can correspond to when the wireless device is uncovered and the second OS circle can correspond to when the wireless device is covered by a particular sleeve or cover.

[0143] In aspects, the set of possible OS circles can correspond to or be associated with various states of the wireless device. For example, the set of possible OS circles can correspond to when the wireless device is uncovered and / or when the wireless device is covered by one or more different types of covers or sleeves.

[0144] In certain aspects, the transmission of the test signal at block 1302 can include using one of the antennas in one of the antenna arrays of the wireless device. The test signal can include a continuous wave signal or an FMCW radar signal. The test signal can be transmitted from the antenna in one of the multiple antenna arrays of the wireless device, and the vertically polarized component signal and the horizontally polarized component signal can be received by another antenna in the same array of the multiple antenna arrays.

[0145] In some aspects, the determination of the environmental scenario at block 1308 can entail identifying whether human tissue is in the vicinity of the wireless device. For example, the determination of the environmental scenario can include the wireless device distinguishing whether the antenna of the wireless device is blocked by a covering or by human tissue.

[0146] According to certain aspects, the covering can include a protective case for the wireless device. For example, the covering can be a case for a mobile phone or a smartphone. The covering can include various materials, such as plastic, rubber, or leather.

[0147] In certain aspects, the cross-polarization captures can be indicative of the cross-polarization component signals received at block 1302. For example, each of the multiple cross-polarization captures can be based on a cross-polarization ratio between the vertically polarized component signal and the horizontally polarized component signal.

[0148] According to certain aspects, the cross-polarization captures associated with the multiple antenna arrays can be used to detect the OS circles associated with the current covered / uncovered state of the wireless device. For example, the detection at block 1304 can include the wireless device detecting that the first cross-polarization capture from the first antenna array corresponds to the first OS circle and the second OS circle, and detecting that the second cross-polarization capture from the second antenna array corresponds to the first OS circle, but not to the second OS circle. Based on the first OS circle corresponding to the first antenna array and the second antenna array, the wireless device can identify that the first OS circle is the OS circle corresponding to the current covered / uncovered state of the wireless device.

[0149] While various examples are described herein with respect to OS circles for identifying an environmental scenario or corresponding to an uncovered or covered state of a wireless device for ease of understanding, aspects of the present disclosure can also be applied to other suitable regions (e.g., polygons) in the IQ plane. For example, a particular polygon in the IQ plane can be indicative of an OS state of the wireless device.

[0150] The various operations of methods described above can be performed by any suitable means depending on the implementation. The means can include various hardware and / or software component(s) and / or module(s), including, but not limited to a circuit, an application-specific integrated circuit (ASIC), or processor. Generally, where there are operations illustrated in figures, those operations can have corresponding counterpart means-plus-function. For example, means for receiving can include Figure 2 the RX front end circuitry 254a-254r and / or antennas 252a-252r of the Figure 3 the reception path 304 and / or antennas 303 of the Figure 2 the TX front end circuitry 254a-254r and / or antennas 252a-252r of the Figure 3 the transmission path 302 and / or antennas 303 of the Figure 2 the reception processor 258, the controller / processor 280, and / or the transmission processor 264 of the Figure 4B the processor 422 of the

[0151] Example Aspects

[0152] In addition to the various aspects described above, specific combinations of aspects are within the scope of the present disclosure, some of which are described in detail below:

[0153] A first aspect. A method for wireless communications by a user equipment (UE), comprising: receiving a plurality of cross-polarization captures from a plurality of antenna arrays of the UE; detecting that the plurality of cross-polarization captures from the plurality of antenna arrays correspond to a first open space (OS) circle in an in-phase / quadrature (IQ) plane of a set of possible OS circles of the UE; based on the detecting, assigning the first OS circle as an active OS circle of the UE and deactivating other possible OS circles in the set; determining an environmental scenario corresponding to the active OS circle; and transmitting a signal using a transmission power based on the determined environmental scenario.

[0154] A second aspect. The method of the first aspect, further comprising: receiving a further plurality of cross-polarization captures from the plurality of antenna arrays of the UE; detecting that the further plurality of cross-polarization captures from the plurality of antenna arrays correspond to a second OS circle in the IQ plane of the set of possible OS circles, the second OS circle being different from the first OS circle; and based on the detecting the correspondence to the second OS circle, assigning the second OS circle as the active OS circle of the UE and deactivating other possible OS circles in the set, including the first OS circle.

[0155] Third aspect. The method of the first aspect or the second aspect, wherein the set of possible OS circles corresponds to the UE being uncovered and to one or more different types of coverings of the UE.

[0156] Fourth aspect. The method of the first aspect through the third aspect, further comprising transmitting at least one test signal from the UE.

[0157] Fifth aspect. The method of the fourth aspect, wherein the at least one test signal comprises a continuous wave signal or a frequency modulated continuous wave (FMCW) radar signal.

[0158] Sixth aspect. The method of the fourth aspect, wherein the at least one test signal is transmitted from an antenna in one of a plurality of antenna arrays of the UE, and wherein the vertically polarized component signal and the horizontally polarized component signal are received by another antenna in a same array of the plurality of antenna arrays.

[0159] Seventh aspect. The method of any one of the first aspect through the sixth aspect, wherein determining the environmental scenario comprises distinguishing whether an antenna of the UE is obstructed by a covering or by human tissue.

[0160] Eighth aspect. The method of the seventh aspect, wherein the covering comprises a protective sleeve for the UE.

[0161] Ninth aspect. The method of any one of the first aspect through the eighth aspect, wherein each of the plurality of cross-polarization captures is based on a cross-polarization ratio between the vertically polarized component signal and the horizontally polarized component signal.

[0162] Tenth aspect. The method of any one of the first aspect through the ninth aspect, wherein the detecting comprises detecting that a first cross-polarization capture from a first antenna array corresponds to a first OS circle and a second OS circle, and detecting that a second cross-polarization capture from a second antenna array corresponds to the first OS circle but does not correspond to the second OS circle.

[0163] Eleventh aspect. An apparatus for wireless communication, comprising: a plurality of antenna arrays; a receiver configured to receive a plurality of cross-polarization captures from the plurality of antenna arrays; a memory; a processor coupled to the memory, the processor and the memory configured to: detect that the plurality of cross-polarization captures from the plurality of antenna arrays correspond to a first open space (OS) circle in an in-phase / quadrature (IQ) plane of a set of possible OS circles of the apparatus; based on the detecting, assign the first OS circle as an active OS circle of the apparatus and deactivate other possible OS circles in the set; and determine an environmental scenario corresponding to the active OS circle; and a transmitter configured to transmit a signal using a transmission power based on the determined environmental scenario.

[0164] Twelfth aspect. The apparatus of the eleventh aspect, wherein the receiver is configured to receive a further plurality of cross-polarization captures from a plurality of antenna arrays of the apparatus; and the processor and memory are further configured to detect that the further plurality of cross-polarization captures from the plurality of antenna arrays correspond to a second OS circle in the IQ plane in the set of possible OS circles, the second OS circle being different from the first OS circle; and based on detecting the correspondence to the second OS circle, assign the second OS circle as an active OS circle of the apparatus and deactivate other possible OS circles in the set, including the first OS circle.

[0165] Thirteenth aspect. The apparatus of the eleventh aspect or the twelfth aspect, wherein the set of possible OS circles correspond to the apparatus being uncovered, and to one or more different types of coverings of the apparatus.

[0166] Fourteenth aspect. The apparatus of any one of the eleventh aspect through the thirteenth aspect, wherein the transmitter is further configured to transmit at least one test signal.

[0167] Fifteenth aspect. The apparatus of the fourteenth aspect, wherein an antenna in one of the plurality of antenna arrays of the apparatus is configured to transmit the at least one test signal, and wherein another antenna in a same array of the plurality of antenna arrays is configured to receive the vertically polarized component signal and the horizontally polarized component signal.

[0168] Sixteenth aspect. The apparatus of any one of the eleventh aspect through the fifteenth aspect, wherein the processor and the memory are further configured to distinguish whether an antenna of the apparatus is blocked by a covering or by human tissue.

[0169] Seventeenth aspect. The apparatus of the sixteenth aspect, wherein the covering comprises a protective case for the UE.

[0170] Eighteenth aspect. The apparatus of any one of the eleventh aspect through the seventeenth aspect, wherein each of the plurality of cross-polarization captures is based on a cross-polarization ratio between the vertically polarized component signal and the horizontally polarized component signal.

[0171] Nineteenth aspect. The apparatus of any one of the eleventh aspect through the eighteenth aspect, wherein the processor and the memory are further configured to detect that the first cross-polarization capture from the first antenna array corresponds to the first OS circle and the second OS circle; and detect that the second cross-polarization capture from the second antenna array corresponds to the first OS circle but does not correspond to the second OS circle.

[0172] A twentieth aspect. An apparatus for wireless communication, comprising: means for receiving a plurality of cross-polarization captures from a plurality of antenna arrays of the apparatus; means for detecting that the plurality of cross-polarization captures from the plurality of antenna arrays correspond to a first open space (OS) circle in an in-phase / quadrature (IQ) plane of a set of possible OS circles of a device; means for assigning, based on the detecting, the first OS circle as an active OS circle of the apparatus and deactivating other possible OS circles in the set; means for determining an environmental scenario corresponding to the active OS circle; and means for transmitting a signal using a transmission power based on the determined environmental scenario.

[0173] As used herein, the term “determining” encompasses a wide variety of actions. For example, “determining” can include calculating, computing, processing, deriving, investigating, looking up (e.g., looking up in a table, a database or another data structure), ascertaining and the like. Also, “determining” can include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory) and the like. Also, “determining” can include resolving, selecting, choosing, establishing and the like.

[0174] As used herein, the term “determining” encompasses a wide variety of actions. For example, “determining” can include calculating, computing, processing, deriving, investigating, looking up (e.g., looking up in a table, a database or another data structure), ascertaining and the like. Also, “determining” can include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory) and the like. Also, “determining” can include resolving, selecting, choosing, establishing and the like.

[0175] The various illustrative logical blocks, modules, and circuits described in connection with the disclosure can be implemented or performed 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. The general purpose processor can be a microprocessor, but in the alternative, the processor can be any commercially available processor, controller, microcontroller, or state machine. A processor can 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.

[0176] The methods disclosed herein include one or more steps or actions for achieving the described method. The method steps and / or actions can be interchanged with one another without departing from the scope of the claims. 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.

[0177] The described functions can be carried out in hardware, software, firmware, or any combination thereof. If implemented in hardware, an example hardware configuration can include a processing system in a wireless node. The processing system can be implemented with a bus architecture, as described below. The bus can include any number of interconnecting buses and bridges depending on the specific application of the processing system and the overall design constraints. The bus can link together various circuits including processors, machine-readable media, and buses. Bus interfaces can be used to connect network adapters and the like to the processing system via the bus. Network adapters can be utilized to implement signal processing functions of the physical (PHY) layer. In the case of user terminals, user interfaces (e.g., keyboards, displays, mice, joysticks, etc.) can also be connected to the bus. The bus can also link various other circuits such as timing sources, peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further.

[0178] The processing system can be configured as a general-purpose processing system with one or more microprocessors and external memory providing processor functions and at least a portion of machine-readable media, all linked together with an external bus architecture. Alternatively, the processing system can be implemented with an ASIC, with the processor, the bus interface, the user interface in the case of an access terminal, supporting circuitry, and at least a portion of machine-readable media integrated into a single chip, or with one or more FPGAs, PLDs, controllers, state machines, gated logic, discrete hardware components, or any other suitable circuitry, or any combination of circuits designed to perform the various functionality described throughout this disclosure. One of ordinary skill in the art will recognize how best to implement the described functionality for the processing system, depending on the particular application and the overall design constraints imposed on the overall system.

[0179] It is to be understood that the claims are not limited to the precise configurations and components described above. Various modifications, changes, and variations apparent to those skilled in the art can be made in the arrangement, operation, and details of the methods and devices described without departing from the scope of the claims.

Claims

1. A method for wireless communications by a user equipment (UE), comprising: receiving a plurality of cross-polarization captures from a plurality of antenna arrays of the UE, the captures including information indicative of IQ plane data associated with co-orthogonal (IQ) planes of one or more signals received at the UE; and transmitting a signal using a transmission power based on an environmental scenario associated with the IQ plane data.

2. The method of claim 1, wherein, the IQ plane data includes a cross-polarization ratio between a vertical polarization component signal and a horizontal polarization component signal.

3. The method of claim 1, further comprising: receiving a further plurality of cross-polarization captures from the plurality of antenna arrays of the UE, the further plurality of cross-polarization captures including information indicative of second IQ plane data, the second IQ plane data being different than the IQ plane data; and transmitting the signal using a transmission power based on an environmental scenario associated with the second IQ plane data, while ignoring the IQ plane data.

4. The method of claim 1, wherein, the environmental scenario corresponds to one of: an antenna of the UE being obstructed by a cover or being obstructed by human tissue.

5. The method of claim 4, wherein, the cover includes a protective case for the UE.

6. The method of claim 2, wherein, a phase and amplitude of the cross-polarization ratio identifies an open space (OS), and wherein the transmission of the signal is based on the identified OS.

7. The method of claim 1, further comprising: detecting whether the plurality of cross-polarization captures from the plurality of antenna arrays correspond to a first open space (OS) circle in the IQ plane that is supported by the UE out of a set of OS circles; and assigning the first OS circle as an active OS circle for the UE and deactivating other supported OS circles in the set based on the detection.

8. The method of claim 7, wherein, the first OS circle is identified based on a cross-polarization ratio between a vertical polarization component signal and a horizontal polarization component signal.

9. An apparatus for wireless communications by a user equipment (UE), comprising: a memory; and one or more processors coupled with the memory, wherein the one or more processors are configured to cause the UE to: receive a plurality of cross-polarization captures from a plurality of antenna arrays of the UE, the captures including information indicative of IQ plane data associated with co-orthogonal (IQ) planes of one or more signals received at the UE; and transmit a signal using a transmission power based on an environmental scenario associated with the IQ plane data. the IQ plane data includes a cross-polarization ratio between a vertical polarization component signal and a horizontal polarization component signal.

10. The apparatus of claim 9, wherein, the one or more processors are further configured to cause the UE to:

11. The apparatus of claim 9, wherein, receive a further plurality of cross-polarization captures from the plurality of antenna arrays of the UE, the further plurality of cross-polarization captures including information indicative of second IQ plane data, the second IQ plane data being different than the IQ plane data; and transmit the signal using a transmission power based on an environmental scenario associated with the second IQ plane data, while ignoring the IQ plane data. the environmental scenario corresponds to one of: an antenna of the UE being obstructed by a cover or being obstructed by human tissue.

12. The apparatus of claim 9, wherein, the cover includes a protective case for the UE.

13. The apparatus of claim 12, wherein, ​ 14. The apparatus of claim 10, wherein, a phase and magnitude of the cross-polarization ratio identifies an open space OS, and wherein transmission of the signal is based on the identified OS.

15. The apparatus of claim 9, wherein, The one or more processors are further configured to cause the UE to: detect whether a plurality of cross-polarization captures from the plurality of antenna arrays correspond to a first open space (OS) circle in the IQ plane from a set of OS circles supported by the UE; and assign the first OS circle as an active OS circle for the UE and deactivate other supported OS circles in the set based on the detection.

16. The apparatus of claim 15, wherein, The first OS circle is identified based on a cross-polarization ratio between a vertical polarization component signal and a horizontal polarization component signal.

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