Radio frequency (RF) exposure compliance

Abstract

Certain aspects of this disclosure provide techniques and apparatus for determining transmit power based on transmission patterns and / or future conditions while maintaining radio frequency (RF) exposure compliance. Example methods typically include acquiring a pattern associated with one or more first transmissions, determining transmit power for one or more second transmissions based at least in part on that pattern and RF exposure limits, and transmitting one or more second transmissions at the determined transmit power.

Description

Technical Field

[0001] This patent application claims priority to U.S. Provisional Application No. 63 / 113,488, filed November 13, 2020; U.S. Provisional Application No. 63 / 141,834, filed January 26, 2021; U.S. Provisional Application No. 63 / 152,773, filed February 23, 2021; and U.S. Provisional Application No. 63 / 175,464, filed April 15, 2021, each of which is hereby expressly incorporated herein by reference in its entirety.

[0002] This disclosure relates to various aspects of wireless communications, and more specifically to determining transmit power while maintaining radio frequency (RF) exposure compliance. Prior Technology

[0003] Wireless communication systems are widely deployed to provide various telecommunications services, such as telephone, video, data, messaging, and broadcasting. Modern wireless communication equipment (e.g., cellular phones) typically needs to meet radio frequency (RF) exposure limits set by domestic and international standards and regulations. To ensure compliance, such equipment currently undergoes an extensive certification process before being released to the market. To ensure that wireless communication equipment complies with RF exposure limits, various technologies have been developed to enable wireless communication equipment to assess RF exposure from other devices and adjust the transmission power accordingly to meet these limits. Summary of the Invention

[0004] The systems, methods, and apparatuses of this disclosure each have several aspects, and no single aspect is solely responsible for its desired properties. Without limiting the scope of this disclosure as expressed in the appended claims, some features will now be briefly discussed. After considering this discussion, and especially after reading the section entitled "Detailed Description," one will understand how the features of this disclosure provide advantages, including desirable transmit power that complies with radio frequency (RF) exposure limits.

[0005] Certain aspects of the subject matter described in this disclosure can be implemented in a method of wireless communication performed by a user equipment (UE). The method generally includes acquiring a pattern associated with one or more first transmissions; determining a transmit power for one or more second transmissions based at least in part on the pattern and RF exposure limitations; and transmitting the one or more second transmissions at the determined transmit power.

[0006] Certain aspects of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication. The apparatus generally includes memory, a processor, and a transmitter. The processor is coupled to the memory such that the processor and memory are configured to acquire a mode associated with one or more first transmissions and determine a transmit power for one or more second transmissions based at least in part on the mode and RF exposure limits; and the transmitter is configured to transmit one or more second transmissions at the determined transmit power.

[0007] Certain aspects of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication. The apparatus generally includes components for acquiring a pattern associated with one or more first transmissions; components for determining a transmit power for one or more second transmissions based at least in part on the pattern and RF exposure limits; and components for transmitting one or more second transmissions at the determined transmit power.

[0008] Certain aspects of the subject matter described in this disclosure may be implemented in a computer-readable medium having instructions stored thereon for: acquiring a pattern associated with one or more first transmissions; determining a transmit power for one or more second transmissions based at least in part on the pattern and RF exposure limits; and transmitting one or more second transmissions at the determined transmit power.

[0009] Certain aspects of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication. The apparatus generally includes a memory and a processor coupled to the memory. The processor and memory are configured to: acquire a mode associated with one or more first transmissions, determine a transmit power for one or more second transmissions based at least in part on the mode and radio frequency (RF) exposure limits, and transmit the one or more second transmissions at the determined transmit power.

[0010] Certain aspects of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication. The apparatus generally includes a memory and a processor coupled to the memory. The processor and memory are configured to: acquire data for transmission to a receiving entity and radio conditions associated with the transmission; determine a transmission time associated with the data based at least in part on the radio conditions; and transmit a signal indicating the data to the receiving entity at a transmission power limited by radio frequency (RF) exposure, based at least in part on the determined transmission time.

[0011] Certain aspects of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication. The apparatus generally includes a memory and a processor coupled to the memory. The processor and memory are configured to: select a transmission mode from a plurality of transmission modes based on data for transmission from the apparatus to a receiving entity and one or more radio conditions associated with the transmission; and transmit a signal indicating the data to the receiving entity at a transmit power at least in part based on the selected transmission mode and radio frequency (RF) exposure limits.

[0012] Certain aspects of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication. The apparatus generally includes: acquiring data for transmission to a receiving entity and radio conditions associated with the transmission; determining a transmission time associated with the data based at least in part on the radio conditions; and transmitting a signal indicating the data to the receiving entity at a transmission power limited by radio frequency (RF) exposure, based at least in part on the determined transmission time.

[0013] Certain aspects of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication. The apparatus generally includes: selecting a transmission mode from a plurality of transmission modes based on data for transmission from a wireless device to a receiving entity and one or more radio conditions associated with the transmission; and transmitting a signal indicating data to the receiving entity at a transmit power at least in part based on the selected transmission mode and radio frequency (RF) exposure limits.

[0014] Certain aspects of the subject matter described in this disclosure can be implemented in a computer-readable medium having instructions stored thereon for: acquiring data for transmission to a receiving entity and radio conditions associated with the transmission; determining a transmission time associated with the data based at least in part on the radio conditions; and transmitting a signal indicating the data to the receiving entity at a transmission power based at least in part on the determined transmission time and a radio frequency (RF) exposure limit.

[0015] Certain aspects of the subject matter described in this disclosure may be implemented in a computer-readable medium having instructions stored thereon for: selecting a transmission mode from a plurality of transmission modes based on data transmitted from a wireless device to a receiving entity and one or more radio conditions associated with the transmission; and transmitting a signal indicating data to the receiving entity at a transmit power at least in part based on the selected transmission mode and radio frequency (RF) exposure limits.

[0016] Certain aspects of the subject matter described in this disclosure can be implemented in a method of wireless communication by a wireless device. The method generally includes: acquiring data for transmission to a receiving entity and radio conditions associated with the transmission; determining a transmission time associated with the data based at least in part on the radio conditions; and transmitting a signal indicating the data to the receiving entity at a transmission power limited by radio frequency (RF) exposure, based at least in part on the determined transmission time.

[0017] Certain aspects of the subject matter described in this disclosure can be implemented in a method of wireless communication by a wireless device. The method generally includes: selecting a transmission mode from a plurality of transmission modes based on data transmitted from the wireless device to a receiving entity and one or more radio conditions associated with the transmission; and transmitting a signal indicating data to the receiving entity at a transmit power at least in part based on the selected transmission mode and radio frequency (RF) exposure limits.

[0018] To achieve the foregoing and related objectives, one or more aspects include features fully described below and specifically pointed out in the claims. The following description and drawings illustrate certain illustrative features of one or more aspects in detail. However, these features indicate only a few of the various ways in which the principles of each aspect can be employed. Simple Explanation of the Diagram

[0019] To gain a more detailed understanding of the foregoing features of this disclosure, reference can be made to a more specific description of the aspects briefly summarized above, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only certain typical aspects of this disclosure and should therefore not be considered as limiting its scope, as the description may allow for other equally valid aspects.

[0020] Figure 1 is a block diagram conceptually illustrating an example wireless communication network according to certain aspects of this disclosure.

[0021] Figure 2 is a block diagram conceptually illustrating the design of an example base station (BS) and user equipment (UE) according to certain aspects of this disclosure.

[0022] Figure 3 is a block diagram of an example radio frequency (RF) transceiver according to certain aspects of this disclosure.

[0023] Figure 4 is a diagram illustrating an example of a combination of normalized specific absorptivity (SAR) distribution and normalized power density (PD) distribution according to certain aspects of this disclosure.

[0024] Figures 5A, 5B, and 5C are diagrams illustrating examples of transmit power over time that conforms to certain aspects of this disclosure and meets RF exposure limits.

[0025] Figure 6 is a flowchart illustrating an example operation for wireless communication according to certain aspects of this disclosure.

[0026] Figures 7A, 7B, 8A, 8B and 9A are diagrams illustrating example modes for determining one or more transmit powers over time according to certain aspects of this disclosure.

[0027] Figure 9B is a diagram illustrating the application of the transmit power limit based on the pattern depicted in Figure 9A according to certain aspects of this disclosure.

[0028] Figures 10A and 10B are flowcharts illustrating example operations for wireless communication according to certain aspects of this disclosure.

[0029] Figures 11A to 11C are figures 1100A to 1100C of transmit power (P(t)) over time according to certain aspects of this disclosure, showing the time-averaged mode using dynamic reserve power.

[0030] Figure 12 illustrates a communication device (e.g., UE) according to certain aspects of this disclosure, which may include various elements configured to perform operations using the techniques disclosed herein.

[0031] For ease of understanding, the same reference numerals are used where possible to denote common elements shared by the figures. It is anticipated that elements disclosed in one aspect may be usefully applied to other aspects without specific description. Implementation

[0032] Various aspects of this disclosure provide apparatus, methods, processing systems, and computer-readable media for ensuring radio frequency (RF) exposure compliance based on one or more modes and / or future conditions.

[0033] In some cases, time averaging of RF exposure can be performed to comply with RF exposure limits within a specified time window. A multi-mode / multi-band wireless communication device has multiple transmit antennas that can be configured to transmit simultaneously in one or more sub-6 GHz bands and / or one or more bands above 6 GHz (such as mmWave (e.g., FR2) or FR3 bands). As described herein, RF exposure in sub-6 GHz bands can be evaluated in terms of specific absorption rate (SAR), while RF exposure in bands above 6 GHz can be evaluated in terms of power density (PD). Due to regulations regarding simultaneous exposure, the wireless communication device may limit the maximum transmit power for sub-6 GHz bands and / or bands above 6 GHz.

[0034] Aspects of the present disclosure provide enhanced techniques for ensuring RF exposure compliance, for example, based on one or more modes and / or future conditions. The mode can include a transmit power mode (e.g., transient transmit power as a function of time) associated with past transmissions over various time periods (such as the past few minutes, hours, or days) and / or an application mode indicating periodic traffic bursts that an application (such as a voice or video call application) can generate. In some aspects, the mode can be used to identify when an upcoming transmission will occur, and the mode can be related to various characteristics associated with the upcoming transmission, such as transmit time, transmit power over time, antenna switching, network conditions, sensor information, etc. <000​​​​​In some aspects, the UE can consider future conditions (such as transmission time and / or radio conditions) when determining the transmit power for RF exposure compliance. Various aspects of this disclosure provide techniques and apparatus for switching between various transmission modes (e.g., as described herein) based on the transmission time associated with data and / or radio conditions while ensuring RF exposure compliance. In some aspects, the transmission time can be derived from the size associated with the data (e.g., data buffer size) and the current data rate. For example, if the data buffer size is large (e.g., the transmission time is greater than the time window associated with the RF exposure limit), the transmitter can operate in peak mode to achieve continuous transmission at the maximum average power level (e.g., P limit). If the data buffer size is small (e.g., the transmission time is less than the time window associated with the RF exposure limit), the transmitter can operate in time-averaged mode and can transmit at maximum power to complete the transmission if there is sufficient reserve power margin for high-power transmission. The transmission time can be determined based on the data buffer size and radio conditions. For example, the signal or communication environment can limit or indicate the amount of transmission or data that can be transmitted in a transient time or within an upcoming time period. In some respects, the determined transmission time can be based on actual or measured values. For example, radio conditions can be determined based on measured RSRP. In other respects, the determined transmission time can be based on predicted values, such as those based on one or more patterns. For example, radio conditions can be determined based on path loss that a user might experience at a certain time of day or at a specific location indicated by a pattern.

[0037] The various techniques described in this paper for ensuring RF exposure compliance can achieve the desired transmit power for data transmission. Ideal transmit power can provide ideal uplink / sidelink performance, such as ideal data rates, carrier aggregation, and / or connectivity at the community edge.

[0038] The following description provides examples of RF exposure compliance in communication systems and does not limit the scope, applicability, or examples set forth in the claims. Changes may be made to the function and arrangement of the elements discussed without departing from the scope of this disclosure. Various processes or elements may be omitted, substituted, or added as appropriate in various examples. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Furthermore, features described with respect to some examples may be combined in some other examples. For example, an apparatus may be implemented using any number of aspects set forth herein, or a method may be practiced using any number of aspects set forth herein. Furthermore, the scope of this disclosure is intended to cover apparatus or methods that may be practiced using structures, functions, or structures and functions other than those set forth herein. It should be understood that any aspect of this disclosure disclosed herein may be embodied by one or more elements of the claims. 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 preferential or superior to other aspects.

[0039] Generally, any number of wireless networks can be deployed in a given geographical area. Each wireless network can support a specific Radio Access Technology (RAT) and can operate on one or more frequencies. RAT can also be referred to as radio technology, air interface, etc. Frequency can also be referred to as carrier, subcarrier, frequency channel, tone, subband, etc. Each frequency can support a single RAT in a given geographical area to avoid interference between wireless networks using different RATs, or it can support multiple RATs.

[0040] The techniques described herein can be used in a variety of wireless networks and radio technologies. While terms commonly associated with 3G, 4G, and / or newer radio technologies (e.g., 5G NR) may be used to describe aspects herein, aspects of this disclosure can be applied to other generation-based communication systems and / or wireless technologies such as 802.11, 802.15, etc.

[0041] NR access can support a variety of wireless communication services, such as enhanced mobile broadband (eMBB) for wide bandwidths (e.g., 80 MHz or above), millimeter wave (mmWave) for high carrier frequencies (e.g., 24 GHz to 53 GHz or above), massive MTC (mMTC) for non-backward compatible machine-type communication MTC technologies, and / or mission-critical ultra-reliable low-latency communication (URLLC). These services may have specific latency and reliability settings. They may also have different transmission time intervals (TTIs) to meet corresponding quality of service (QoS) settings. Furthermore, these services may coexist in the same subframe. NR supports beamforming, and the beam direction can be dynamically configured. It can also support pre-coded multiple-input multiple-output (MIMO) transmissions, such as multi-layer transmission. It can support aggregation of multiple communities.

[0042] Figure 1 illustrates an example wireless communication network 100 in which various aspects of this disclosure may be implemented. For example, the wireless communication network 100 may be an NR system (e.g., a 5G NR network), an evolved Universal Terrestrial Radio Access (E-UTRA) system (e.g., a 4G network), a Universal Mobile Telecommunications System (UMTS) (e.g., a 2G / 3G network), or a Code Division Multiple Access (CDMA) system (e.g., a 2G / 3G network), or may be configured to communicate according to IEEE standards (e.g., one or more of the 802.11 standards), etc.

[0043] As shown in Figure 1, the wireless communication network 100 may include multiple BSs 110a-z (each also individually referred to herein as BS 110 or collectively as BS 110) and other network entities. BS 110 may provide communication coverage for a specific geographic area, sometimes referred to as a "community," which may be stationary or mobile depending on the location of the moving BS 110. In some examples, BS 110 may interconnect with each other and / or interconnect to one or more other BSs or network nodes (not shown) in the wireless communication network 100 using any suitable transport network through various types of backhaul interfaces (e.g., direct physical connection, wireless connection, virtual network, etc.). In the example shown in Figure 1, BS 110a, 110b, and 110c may be macro BSs for macro communities 102a, 102b, and 102c, respectively. BS 110x may be a pico BS for pico community 102x. BS 110y and 110z may be femto BSs for femto communities 102y and 102z, respectively. A single business unit (BS) can support one or more communities.

[0044] BS 110 communicates with UEs 120a-y (each also individually referred to herein as UE 120 or collectively as UE 120) in the wireless communication network 100. As shown in FIG1, according to various aspects of this disclosure, UE 120a includes an RF exposure manager 122, which determines the transmit power for transmission to a receiving entity (such as BS 110a or another UE 120) based on various modes and / or future conditions. UEs 120 (e.g., 120x, 120y, etc.) may be distributed throughout the wireless communication network 100, and each UE 120 may be fixed or mobile. The wireless communication network 100 may also include a relay station (e.g., relay station 110r), also referred to as a relay, which receives data and / or other information transmissions from an upstream station (e.g., BS 110a or UE 120r) and sends data and / or other information transmissions to a downstream station (e.g., UE 120 or BS 110), or relays transmissions between UEs 120 to facilitate communication between devices.

[0045] Network controller 130 can communicate with a group of BSs 110 and provide coordination and control for these BSs 110 (e.g., via backhaul). In some cases, network controller 130 may include centralized units (CUs) and / or distributed units (DUs), for example, in a 5G NR system. In some aspects, network controller 130 can communicate with core network 132 (e.g., a 5G core network (5GC)) which provides various network functions such as access and mobility management, session management, user plane functions, policy control functions, authentication server functions, unified data management, application functions, network exposure functions, network repository functions, network slice selection functions, etc.

[0046] Another wireless device in the wireless communication network 100 may alternatively or additionally include an RF exposure manager. For example, one or more BS 110s may be configured as customer premises equipment (CPE), and the RF exposure manager configured as described herein may be implemented in the BS or CPE.

[0047] Figure 2 shows example elements of BS 110a and UE 120a that can be used to implement various aspects of this disclosure (e.g., the wireless communication network 100 of Figure 1).

[0048] At BS 110a, the transmit processor 220 can receive data from the data source 212 and control information from the controller / processor 240. The control information can be used for the Entity Broadcast Channel (PBCH), Entity Control Format Indicator Channel (PCFICH), Entity Hybrid ARQ Indicator Channel (PHICH), Entity Downlink Control Channel (PDCCH), Group Common PDCCH (GC PDCCH), etc. The data can be used for the Entity Downlink Shared Channel (PDSCH), etc. The Media Access Control (MAC) control element (MAC-CE) is a MAC layer communication structure that can be used for exchanging control commands between wireless nodes. The MAC-CE can be carried in a shared channel, such as the Entity Downlink Shared Channel (PDSCH), Entity Uplink Shared Channel (PUSCH), or Entity Sidelink Shared Channel (PSSCH).

[0049] Processor 220 can process (e.g., encode and symbol map) data and control information to acquire data symbols and control symbols, respectively. Transmit processor 220 can also generate reference symbols, such as those for the primary synchronization signal (PSS), secondary synchronization signal (SSS), PBCH demodulation reference signal (DMRS), and channel status information reference signal (CSI-RS). Transmit (TX) multiple-input multiple-output (MIMO) processor 230 can perform spatial processing (e.g., precoding) on ​​data symbols, control symbols, and / or reference symbols (if applicable) and can provide output symbol streams to modulators (MODs) in transceivers 232a-232t. Each modulator in transceivers 232a-232t can process the corresponding output symbol stream (e.g., for OFDM, etc.) to acquire an output sample stream. Each of transceivers 232a-232t can further process (e.g., convert to analog, amplify, filter, and up-convert) the output sample stream to acquire a downlink signal. Downlink signals from transceivers 232a-232t can be transmitted via antennas 234a-234t respectively.

[0050] At UE 120a, antennas 252a-252r can receive downlink signals from BS 110a and can provide the received signals to demodulators (DEMODs) in transceivers 254a-254r respectively. Each transceiver in transceivers 254a-254r can modulate (e.g., filter, amplify, downconvert, and digitize) the corresponding received signal to obtain input samples. Each demodulator in transceivers 254a-254r can further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. MIMO detector 256 can obtain received symbols from all demodulators in transceivers 254a-254r, perform MIMO detection on the received symbols (if applicable), and provide the detected symbols. Receiver processor 258 can process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for UE 120a to data slot 260, and provide decoding control information to controller / processor 280.

[0051] On the uplink, at UE 120a, transmit processor 264 can receive and process data from data source 262 (e.g., for the Physical Uplink Common Channel (PUSCH)) and control information from controller / processor 280 (e.g., for the Physical Uplink Control Channel (PUCCH)). Transmit processor 264 can also generate reference symbols for reference signals (e.g., for a sounding reference signal (SRS)). If applicable, symbols from transmit processor 264 can be pre-encoded by TX MIMO processor 266 for further processing by modulators (MODs) and other components in transceivers 254a-254r (e.g., for SC-FDM, etc.) and transmitted to BS 110a. At BS 110a, the uplink signal from UE 120a can be received by antenna 234, processed by modulators and other components in transceivers 232a-232t, detected by MIMO detector 236 (if applicable), and further processed by receiver processor 238 to obtain decoded data and control information transmitted by UE 120a. Receiver processor 238 can provide the decoded data to data slot 239 and the decoded control information to controller / processor 240.

[0052] Memory modules 242 and 282 can store data and code for BS 110a and UE 120a, respectively. Scheduler 244 can schedule UEs for data transmission on downlink and / or uplink.

[0053] Antenna 252, processors 266, 258, 264 and / or controller / processor 280 of UE 120a, and / or antenna 234, processors 220, 230, 238 and / or controller / processor 240 of BS 110a can be used to perform the various techniques and methods described herein. As shown in Figure 2, according to the aspects described herein, controller / processor 280 of UE 120a has an RF exposure manager 281, which determines the transmit power for transmission to a receiving entity (such as BS 110a) based on various modes and / or future conditions. Although shown at the controller / processor, other components of UE 120a and BS 110a can be used to perform the operations described herein.

[0054] NR can utilize Orthogonal Frequency Division Multiplexing (OFDM) with a loop start code (CP) on both the uplink and downlink. NR can support half-duplex operation using Time Division Duplex (TDD). OFDM and Single Carrier Frequency Division Multiplexing (SC-FDM) divide the system bandwidth into multiple orthogonal subcarriers, which are often referred to as tones, bins, etc. Each subcarrier can be modulated using data. Modulated symbols can be transmitted in the frequency domain using OFDM and in the time domain using SC-FDM. The spacing between adjacent subcarriers can be fixed, and the total number of subcarriers can depend on the system bandwidth. The system bandwidth can also be divided into subbands. For example, a subband can cover multiple resource blocks (RBs).

[0055] Although UE 120a is described with respect to Figures 1 and 2 as communicating with a BS and / or within a network, UE 120a can be configured to communicate directly with / transmit directly to another UE 120, or to communicate directly with / transmit directly to another wireless device, without network relay communication. In some respects, BS 110a shown in Figure 2 and described above is an example of another UE 120. [, Example RF transceiver , ] [, , ]

[0056] Figure 3 is a block diagram of an example RF transceiver circuit 300 according to certain aspects of this disclosure, which can be used in any of the aforementioned wireless devices. The RF transceiver circuit 300 includes at least one transmit (TX) path 302 (also referred to as a transmit chain) for transmitting signals via one or more antennas 306 and at least one receive (RX) path 304 (also referred to as a receive chain) for receiving signals via antenna 306. When the TX path 302 and RX path 304 share antenna 306, the paths can be connected to the antennas via an interface 308, which can include any of a variety of suitable RF devices, such as switches, duplexers, co-direction duplexers, multiplexers, etc.

[0057] When receiving an in-phase (I) or quadrature (Q) baseband analog signal from a digital-to-analog converter (DAC) 310, the TX path 302 may include a baseband filter (BBF) 312, a mixer 314, a driver amplifier (DA) 316, and a power amplifier (PA) 318. The BBF 312, mixer 314, and DA 316 may be included in one or more radio frequency integrated circuits (RFICs). In some implementations, the PA 318 may be external to the RFIC(s).

[0058] BBF 312 filters the baseband signal received from DAC 310, and mixer 314 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., upconverting from baseband to RF). This frequency conversion process produces a sum and difference frequency between the LO frequency and the frequency of the baseband signal of interest. The sum and difference frequencies are called beat frequencies. Beat frequencies are typically in the RF range, such that the signal output from mixer 314 is typically an RF signal, which can be amplified by DA 316 and / or PA 318 before being transmitted by antenna 306. Although one mixer 314 is shown, several mixers can be used to upconvert the filtered baseband signal to one or more intermediate frequencies, and then upconvert the intermediate frequency signal to the frequency used for transmission.

[0059] The RX path 304 may include a low-noise amplifier (LNA) 324, a mixer 326, and a baseband filter (BBF) 328. The LNA 324, mixer 326, and BBF 328 may be included in one or more RFICs, which may or may not be the same RFIC including the TX path elements. The RF signal received via antenna 306 may be amplified by the LNA 324, and the mixer 326 mixes the amplified RF signal with a received local oscillator (LO) signal to convert the RF signal of interest to a different baseband frequency (e.g., down-conversion). The baseband signal output from the mixer 326 may be filtered by the BBF 328 before being converted into a digital I or Q signal for digital signal processing by an analog-to-digital converter (ADC) 330.

[0060] Some systems can employ a frequency synthesizer with a voltage-controlled oscillator (VCO) to generate a stable, tunable LO with a specific tuning range. Therefore, the transmit LO can be generated by the TX frequency synthesizer 320, and the transmit LO can be buffered or amplified by amplifier 322 before being mixed with the baseband signal in mixer 314. Similarly, the receive LO can be generated by the RX frequency synthesizer 332, and the receive LO can be buffered or amplified by amplifier 334 before being mixed with the RF signal in mixer 326.

[0061] Controller 336 can direct the operation of RF transceiver circuitry 300, such as transmitting signals via TX path 302 and / or receiving signals via RX path 304. Controller 336 can be a processor, digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA) or other programmable logic device (PLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof. Memory 338 can store data and code used to operate RF transceiver circuitry 300. Controller 336 and / or memory 338 can include control logic. In some cases, controller 336 can determine time-averaged RF exposure measurements based on the transmit power level applied to TX path 302 (e.g., certain gain levels at PA 318) to set transmit power levels that comply with RF exposure limits set by domestic / foreign regulations and / or international standards, as further described herein. Example RF exposure compliance

[0062] RF exposure can be expressed using specific absorption rate (SAR), which measures the energy absorbed per unit mass of human tissue and is measured in watts per kilogram (W / kg). RF exposure can also be expressed using power density (PD), which measures the energy absorbed per unit area and is measured in mW / cm². In some cases, maximum permissible exposure (MPE) limits in terms of PD can be imposed on wireless communication equipment using transmission frequencies above 6 GHz. MPE limits are area-based exposure regulatory indicators, such as an energy density limit defined as watts per square meter x (W / m²), which is averaged over a defined area and time-averaged over a frequency-dependent time window to prevent human exposure hazards represented by tissue temperature variations.

[0063] SAR (Radio Exposure Detection) can be used to assess RF exposure at transmission frequencies below 6 GHz, covering wireless communication technologies such as 2G / 3G (e.g., CDMA), 4G (e.g., LTE), 5G (e.g., NR in the 6 GHz band), and IEEE 802.11ac. PD (Radio Exposure Detection) can be used to assess RF exposure at transmission frequencies above 10 GHz, covering wireless communication technologies such as 5G in the mmWave band, IEEE 802.11ad, and 802.11ay. Therefore, different metrics can be used to assess the RF exposure of different wireless communication technologies.

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

[0065] To assess RF exposure from transmissions using a first technology (e.g., 3G, 4G, 5G, IEEE 802.11ac, etc. in the sub-6 GHz band), a wireless communication device may include multiple SAR distributions for the first technology stored in memory (e.g., memory 282 of FIG. 2 or memory 338 of FIG. 3). Each SAR distribution may correspond to a specific transmission scenario among multiple transmission scenarios supported by the wireless communication device for the first technology. Transmission scenarios may correspond to various combinations of antennas (e.g., antennas 252a to 252r of FIG. 2 or antenna 306 of FIG. 3), frequency bands, channels, and / or body locations, as further discussed below. In some examples, one or more SAR distributions in the SAR distribution include a single value (e.g., a peak value, or a sum of peak values, determined based on the following description).

[0066] The SAR distribution (also known as the SAR map) for each transmission scenario can be generated based on measurements (e.g., electric field measurements) performed using a human model in a test laboratory. After the SAR distribution is generated, it is stored in memory so that a processor (e.g., processor 280 in Figure 2 or controller 336 in Figure 3) can evaluate the RF exposure on an ad-hoc basis, as discussed further below. Each SAR distribution may include a set of SAR values, where each SAR value may correspond to a different location (e.g., on a human model). Each SAR value may include the SAR value averaged at a quality of 1g or 10g at the corresponding location.

[0067] The SAR values ​​in each SAR distribution correspond to a specific transmission power level (e.g., the transmission power level at which SAR values ​​are measured in a test laboratory). Since SAR is scaled using transmission power levels, the processor can scale a SAR distribution for any transmission power level by multiplying each SAR value in the SAR distribution by the following transmission power scaling factor: (1) Where Tx c is the current transmission power level for the corresponding transmission scenario, and Tx SAR is the transmission power level corresponding to the SAR value in the stored SAR distribution (e.g., the transmission power level when measuring SAR values ​​in a test laboratory).

[0068] As described above, wireless communication devices can support multiple transmission scenarios for the first technology. In some aspects, a transmission scenario can be specified by a set of parameters. This set of parameters may include one or more of the following: antenna parameters indicating one or more antennas (i.e., active antennas) used for transmission; frequency band parameters indicating one or more frequency bands (i.e., active frequency bands) used for transmission; channel parameters indicating one or more channels (i.e., active channels) used for transmission; body position parameters indicating the position of the wireless communication device relative to the user's body position (head, torso, away from the body, etc.); and / or other parameters. When a wireless communication device supports a large number of transmission scenarios, performing measurements for each transmission scenario in a test setup (e.g., a test laboratory) can be very time-consuming and expensive. To reduce test time, measurements can be performed for a subset of transmission scenarios to generate SAR distributions for that subset of transmission scenarios. In this example, as discussed further below, SAR distributions for each of the remaining transmission scenarios can be generated by combining two or more SAR distributions from the SAR distributions for the subset of transmission scenarios.

[0069] For example, SAR measurements can be performed for each antenna in the antenna array to generate a SAR distribution for each antenna in the antenna array. In this example, a SAR distribution for a transmission scenario in which two or more antennas are active can be generated by combining the SAR distributions for two or more active antennas.

[0070] In another example, SAR measurements can be performed for each of multiple frequency bands to generate a SAR distribution for each of the multiple frequency bands. In this example, a SAR distribution for a transmission scenario in which two or more frequency bands are active can be generated by combining the SAR distributions for two or more active frequency bands.

[0071] In some respects, the SAR distribution can be normalized relative to the SAR limit by dividing each SAR value in the SAR distribution by the SAR limit. In this case, when the normalized SAR value is greater than 1, the normalized SAR value exceeds the SAR limit, and when the normalized SAR value is less than 1, the normalized SAR value is below the SAR limit. In these respects, each SAR distribution in the SAR distribution stored in memory can be normalized relative to the SAR limit.

[0072] In some respects, a normalized SAR distribution for a transmission scenario can be generated by combining two or more normalized SAR distributions. For example, a normalized SAR distribution for a transmission scenario where two or more antennas are active can be generated by combining normalized SAR distributions for two or more active antennas. Where different transmission power levels are used for the active antennas, the normalized SAR distribution for each active antenna can be scaled to the corresponding 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 the following formula: (2) Where SAR lim is the SAR constraint, SAR norm_combined is the combined normalized SAR distribution for simultaneous transmission from active antennas, i is the index for the active antenna, 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 for the i-th active antenna, and K is the number of active antennas.

[0073] Equation (2) can be rewritten as follows: (3a) Where SAR norm_i is the normalized SAR distribution for the i-th active antenna. When using multiple active antennas to transmit simultaneously at the same transmission frequency (e.g., Multiple-Input Multiple-Output (MIMO)), the combined normalized SAR distribution is obtained by summing the square roots of the individual normalized SAR distributions and calculating the square of the sum, as shown below: (3b).

[0074] In another example, normalized SAR distributions for different frequency bands can be stored in memory. In this example, a normalized SAR distribution for a transmission scenario where two or more frequency bands are active can be generated by combining normalized SAR distributions for two or more active frequency bands. For cases where the transmission power levels for the active frequency bands differ, the normalized SAR distribution for each active frequency band can be scaled to the corresponding transmission power level before combining the normalized SAR distributions for the active frequency bands. In this example, the combined SAR distribution can also be calculated using equation (3a), where i is the index for the 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 for the i-th active frequency band.

[0075] To assess RF exposure from transmissions using a second technology (e.g., 5G, IEEE 802.11ad, 802.11ay, etc. in the 24 to 60 GHz band), the wireless communication device may include multiple PD distributions for the second technology stored in memory (e.g., memory 282 of FIG. 2 or memory 338 of FIG. 3). Each PD distribution may correspond to a specific transmission scenario among multiple transmission scenarios supported by the wireless communication device for the second technology. Transmission scenarios may correspond to various combinations of antennas (e.g., antennas 252a to 252r of FIG. 2 or antenna 306 of FIG. 3), frequency bands, channels, and / or body locations, as further discussed below. In some examples, one or more PD distributions may include a single value (e.g., a peak value, or a sum of peak values, determined based on the following description).

[0076] The PD distribution (also known as the PD map) for each transmission scenario can be generated based on measurements (e.g., electric field measurements) performed using a human model in a test laboratory. After the PD distribution is generated, it is stored in memory so that a processor (e.g., processor 280 in Figure 2 or controller 336 in Figure 3) can evaluate the RF exposure on the fly, as discussed further below. Each PD distribution may include a set of PD values, where each PD value may correspond to a different location (e.g., on a human model).

[0077] The PD values ​​in each PD distribution correspond to a specific transmission power level (e.g., the transmission power level at which PD values ​​are measured in a test lab). Since PDs are scaled using transmission power levels, 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 scaling factor: (4) Where Tx c is the current transmission power level for the corresponding transmission scenario, and Tx PD is the transmission power level corresponding to the PD value in the PD distribution (e.g., the transmission power level when the PD value is measured in a test laboratory).

[0078] As described above, wireless communication devices can support multiple transmission scenarios for the second technology. In some aspects, a transmission scenario can be specified by a set of parameters. This set of parameters may include one or more of the following: antenna parameters indicating one or more antennas (i.e., active antennas) used for transmission; frequency band parameters indicating one or more frequency bands (i.e., active frequency bands) used for transmission; channel parameters indicating one or more channels (i.e., active channels) used for transmission; body position parameters indicating the position of the wireless communication device relative to the user's body position (head, torso, away from the body, etc.); and / or other parameters. When a wireless communication device supports a large number of transmission scenarios, performing measurements for each transmission scenario in a test setup (e.g., a test laboratory) can be very time-consuming and expensive. To reduce test time, measurements can be performed for a subset of transmission scenarios to generate a PD distribution for that subset of transmission scenarios. In this example, as discussed further below, a PD distribution for each of the remaining transmission scenarios can be generated by combining two or more PD distributions from the PD distributions of the subset of transmission scenarios.

[0079] For example, PD measurements can be performed for each antenna in the antenna array to generate a PD distribution for each antenna in the antenna array. In this example, a PD distribution for a transmission scenario in which two or more antennas are active can be generated by combining the PD distributions for two or more active antennas.

[0080] In another example, PD measurements can be performed for each of multiple frequency bands to generate a PD distribution for each of the multiple frequency bands. In this example, a PD distribution for a transmission scenario in which two or more active frequency bands are active can be generated by combining the PD distributions for two or more active frequency bands.

[0081] In some respects, the PD distribution can be normalized relative to the PD limit by dividing each PD value in the PD distribution by the PD limit. In this case, when the normalized PD value is greater than 1, the normalized PD value exceeds the PD limit, and when the normalized PD value is less than 1, the normalized PD value is below the PD limit. In these respects, each PD distribution in the PD distribution stored in memory can be normalized relative to the PD limit.

[0082] In some respects, a normalized PD distribution for a transmission scenario can be generated by combining two or more normalized PD distributions. For example, a normalized PD distribution for a transmission scenario where two or more antennas are active can be generated by combining normalized PD distributions for two or more active antennas. Where different transmission power levels are used for the active antennas, the normalized PD distribution for each active antenna can be scaled to the corresponding 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 the following formula: (5) Where PD lim is the PD limit, PD norm_combined is the combined normalized PD distribution for simultaneous transmission from active antennas, i is the 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, Tx PDi is the transmission power level for the PD distribution for the i-th active antenna, and L is the number of active antennas.

[0083] Equation (5) can be rewritten as follows: (6a) Where PD norm_i is the normalized PD distribution for the i-th active antenna. When using multiple active antennas to transmit simultaneously at the same transmission frequency (e.g., MIMO), the combined normalized PD distribution is obtained by summing the square roots of the individual normalized PD distributions and calculating the square of the sum, as shown below: (6b)

[0084] 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 where two or more frequency bands are active can be generated by combining normalized PD distributions for two or more active frequency bands. For cases where the transmission power levels for the active frequency bands differ, the normalized PD distribution for each active frequency band can be scaled to the corresponding transmission power level before combining the normalized PD distributions for the active frequency bands. In this example, the combined PD distribution can also be calculated using equation (6a), where i is the index of the 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 Tx PDi is the transmission power level for the normalized PD distribution for the i-th active frequency band.

[0085] As described above, UE 120 can simultaneously transmit signals using a first technology (e.g., 3G, 4G, IEEE 802.11ac, etc.) and a second technology (e.g., 5G, IEEE 802.11ad, etc.), wherein RF exposure is measured using different metrics for the first and second technologies (e.g., SAR for the first technology and PD for the second technology). In this case, processor 280 can determine a first maximum allowable power level for the first technology and a second maximum allowable power level for the second technology for transmissions that comply with RF exposure limits in future time slots. During future time slots, the transmission power levels for the first and second technologies are respectively constrained (i.e., bounded) by the determined first and second maximum allowable power levels to ensure compliance with RF exposure limits, as further described below. In this disclosure, unless otherwise stated, the term "maximum allowable power level" refers to the "maximum allowable power level" imposed by RF exposure limits. It should be understood that the "maximum permissible power level" is not necessarily equal to the absolute maximum power level that complies with RF exposure limits, and may be less than the absolute maximum power level that complies with RF exposure limits (e.g., to provide a safety margin). The "maximum permissible power level" can be used to set power level limits for transmissions at the transmitter, such that the power level of the transmission is not allowed to exceed the "maximum permissible power level" to ensure RF exposure compliance.

[0086] Processor 280 can determine a first maximum permissible power level and a second maximum permissible power level as follows. The processor can determine a normalized SAR distribution for a first technique at the first transmit power level, and a normalized PD distribution for a second technique at the second transmit power level. The processor then combines the normalized SAR distribution and the normalized PD distribution to generate a combined normalized RF exposure distribution (hereinafter referred to as the combined normalized distribution). The value at each location in the combined normalized distribution can be determined by combining the normalized SAR value at that location with the normalized PD value at that location, or by other techniques.

[0087] Processor 280 can then determine whether the first and second transmission power levels comply with RF exposure limits by comparing the peak value in the combined normalized distribution with 1. If the peak value is equal to or less than 1 (i.e., condition <= 1 is met), processor 280 can determine that the first and second transmission power levels comply with RF exposure limits (e.g., SAR and PD limits) and use the first and second transmission power levels as the first and second maximum permissible power levels, respectively, during future time slots. If the peak value is greater than 1, processor 280 can determine that the first and second transmission power levels do not comply with RF exposure limits. The conditions for RF exposure compliance for simultaneous transmission using the first and second technologies can be given by the following formula: (7).

[0088] Figure 4 is a plot illustrating normalized SAR distribution 410 and normalized PD distribution 420, wherein normalized SAR distribution 410 and normalized PD distribution 420 are combined to generate combined normalized distribution 430. Figure 4 also illustrates the condition that the peak value in the combined normalized distribution 430 used for RF exposure compliance is equal to or less than 1. Although each of the distributions 410, 420, and 430 is depicted as a two-dimensional distribution in Figure 4, it should be understood that this disclosure is not limited to this example.

[0089] The normalized SAR distribution in Equation (7) can be generated by combining two or more normalized SAR distributions as described above (e.g., for a transmission scenario using multiple active antennas). Similarly, the normalized PD distribution in Equation (7) can be generated by combining two or more normalized PD distributions as described above (e.g., for a transmission scenario using multiple active antennas). In this case, the conditions for RF exposure compliance in Equation (7) can be rewritten using Equations (3a) and (6a) as follows: (8). For the MIMO case, instead, equations (3b) and (6b) can be combined. As shown in equation (8), the combined normalized distribution can be a function of the transmission power level for the first technology and the transmission power level for the second technology. All points in the combined normalized distribution can satisfy the normalization constraint of 1 in equation (8). Furthermore, when the SAR and PD distributions are combined, they can be spatially aligned or aligned with their peak positions, such that the combined distribution given by equation (8) represents the combined RF exposure for a given location of the human body.

[0090] In some cases, the transmitter can ensure RF exposure compliance by operating under one of the following example scenarios: (a) "no reservation time averaging mode", which has no reservation margin that allows disconnection during the time window, (b) "peak mode", as described herein with respect to Figure 5B, or (c) "time averaging mode", as described herein with respect to Figure 5C.

[0091] In some cases, time averaging of RF exposure can be performed to comply with RF exposure limits within a specified time window (T) associated with RF exposure limits (e.g., 2 seconds for the 60 GHz band, 100 or 360 seconds for bands ≤ 6 GHz, etc.). For example, Figure 5A is Figure 500A of transmit power (P(t)) over time within a time window (T) associated with RF exposure limits according to certain aspects of this disclosure. As an example, in some transmission scenarios within the time window (T), transient transmit power may exceed the maximum time-averaged transmit power level P limit. That is, the transmit power may be greater than the maximum time-averaged transmit power level P limit. In some cases, the UE may transmit at P max, where P max is the maximum transmit power supported by the UE. In some cases, the UE may transmit at a transmit power less than or equal to the maximum time-averaged transmit power level P limit in certain transmission scenarios. The maximum time-averaged transmit power level P limit represents a time-averaged threshold for RF exposure limits in terms of transmit power, and in some cases, P limit may be referred to as the maximum time-averaged power level or limit, or the maximum average transmit power level. Figure 500A also shows the gaps between transmission bursts, where the gaps represent periods during which no transmissions are sent from the device.

[0092] In some cases, the transmit power can be maintained at the maximum average transmit power level allowed by RF exposure compliance to achieve continuous transmission during a time window (e.g., P limit). For example, Figure 5B is Figure 500B of transmit power (P(t)) over time according to certain aspects of this disclosure, showing an example where the transmit power is limited to the P limit. As shown, the UE can transmit continuously at the P limit in accordance with RF exposure restrictions.

[0093] Figure 5C is a diagram 500C of transmit power (P(t)) over time according to certain aspects of this disclosure, illustrating a time-averaged pattern that provides a reserve power margin to achieve continuous transmission within a time window (T). As shown, the transmit power can fall back from the maximum transient power (Pmax) to the reserve power (Preserve) before shutting down the transmitter to reserve sufficient transmit power margin (e.g., the difference between Plimit and Preserve), allowing the UE to continue transmitting at a lower power (reserve) to maintain continuous transmission during the time window (e.g., maintaining a radio connection with the receiving entity). In some aspects, Preserve is set as the minimum power used to maintain the connection, or as such a minimum power plus the margin. The transmit duration at Pmax can be referred to as the burst transmit time (or high-power duration). When more margin becomes available in the future (after T seconds), the transmitter can be allowed to transmit again at a higher power (e.g., with a short burst at Pmax).

[0094] In time-averaging mode, the durations of Pmax and Preserve can be controlled by the processor or control logic to ensure that the time-averaged power does not exceed Plimit within the time window. In some respects, the UE can transmit at a power higher than the average power level but lower than Pmax in the time-averaging mode shown in Figure 5C. Although a single transmit burst is shown in Figure 5C, it should be understood that the UE can alternatively utilize multiple transmit bursts within a time window (T), for example, as described herein with respect to Figure 5A, where the transmit burst is separated by periods during which the transmit power is maintained at or below Preserve. Furthermore, it should be understood that the transmit power of each transmit burst can vary (within the burst and / or compared to other bursts), and at least a portion of the burst can be transmitted at a power higher than the maximum average power level (e.g., Plimit).

[0095] Although Figures 5A to 5C illustrate continuous transmission over windows, occasions, bursts, etc., it should be understood that duty cycles for transmission can be implemented. In such an implementation, the transmit power can be periodically zero and maintained at a higher level during other parts of the duty cycle (e.g., the levels shown in Figures 5A to 5C).

[0096] In some respects, the burst transmission time of P(t) at Pmax, calculated for a given Pmax, Plimit, Preserve, and T, can be scaled according to the duty cycle of the transmission to the receiving entity. For example, the burst transmission time can be adjusted by a factor associated with the duty cycle (1 / duty_cycle), where duty_cycle is between [0,1]. As used herein, the duty cycle of a transmission can refer to a portion of a specific period in which transmission is scheduled or allocated. In some respects, the period associated with the burst transmission time can be independent of the time window (T) used for RF exposure compliance. In some cases, the duty cycle can be normalized (e.g., predetermined) and / or varied over time using a specific RAT, for example, due to changes in radio conditions, mobility, and / or user behavior. In some examples, the duty cycle is determined by the base station (e.g., gNB) and transmitted to the UE. In the case of a 100% duty cycle, it can be assumed that the UE is scheduled for continuous transmission, which can result in the transmit power depicted in Figure 5B. In another example, assume that the duration of the burst transmission time is less than the time window and the period of the burst transmission time is greater than the time window, such that a single pulse of the burst transmission time is active (or occurs) within the time window. Since there is no transmission during a portion of the time window (e.g., P(t) can become zero for a portion of the time window), the transmitter can increase the burst transmission time at Pmax. Exemplary RF Exposure Compliance Based on Transmission Mode

[0097] Multi-mode / multi-band UEs have multiple transmit antennas that can be configured to transmit simultaneously in one or more sub-6 GHz bands and / or one or more bands above 6 GHz (such as mmWave bands). As described herein, RF exposure in the sub-6 GHz bands can be assessed based on SAR, while RF exposure in the bands above 6 GHz can be assessed based on PD. Due to regulations regarding simultaneous exposure, wireless communication devices may limit the maximum transmit power in the sub-6 GHz bands and / or the bands above 6 GHz.

[0098] Aspects of the present disclosure provide techniques for ensuring RF exposure compliance based on one or more patterns. The patterns can include transmit power patterns associated with past transmissions over various time periods (such as the past few minutes, hours, or days) and / or application patterns indicating periodic traffic bursts, which can be generated by an application (e.g., a voice or video call application) and / or indicate a particular application or application type being transmitted. In some aspects, the patterns can be used to identify when an upcoming transmission will occur, and the patterns can be related to various characteristics associated with the upcoming transmission, such as transmit time, transmit power over time, antenna switching, network conditions, sensor information, etc.

[0099] As an example, if the pattern indicates that the transmit time of an upcoming transmission is likely to be relatively long (e.g., the transmit time is greater than a time window associated with RF exposure limits) and / or a consistent uplink transmission can be maintained over the time window, the transmitter can allocate a lower power level to the upcoming transmission (e.g., P_limit, where P_limit < P_max). If the pattern indicates that the transmit time of an upcoming transmission is likely to be relatively short (e.g., the transmit time is less than a time window associated with RF exposure limits) and / or the transmission is likely to be discontinuous (e.g., bursts and / or gaps are possible), the transmitter can allocate a high transient power to the upcoming transmission (e.g., higher than P_limit and / or lower than or equal to P_max), but still comply with RF exposure limits.

[0100] The various techniques described herein for ensuring RF exposure compliance can achieve a desired transmit power for data transmission. The desired transmit power can provide desired uplink / sidelink performance, such as desired data rate, carrier aggregation, and / or connection at the community edge.

[0101] FIG. 6 is a flowchart illustrating an example operation 600 for wireless communication in accordance with some aspects of the present disclosure. Operation 600 can be performed, for example, by a UE (e.g., UE 120a in wireless communication network 100). Operation 600 can be implemented as software elements executed and run on one or more processors (e.g., controller / processor 280 of FIG. 2). Additionally, the transmission of signals by the UE in operation 600 can be implemented, for example, via one or more antennas (e.g., antenna 252 of FIG. 2). In some aspects, the transmission and / or reception of signals by the UE can be implemented via a bus interface of one or more processors (e.g., controller / processor 280) that acquire and / or output the signals.

[0102] Operation 600 may begin at box 602, where the UE may acquire a pattern associated with one or more first transmissions. For example, the UE may acquire a transmit power pattern indicating transmit power over time (e.g., past minutes, hours, or days) associated with past transmissions sent by the UE. As used herein, "pattern" generally refers to a characteristic of the first transmission, which may be a past transmission or a sample thereof, and / or a characteristic of the transmitter in the absence of a first transmission (e.g., when the pattern represents no uplink or sidelink traffic). That is, the pattern may be associated with the transmitter in addition to or in lieu of the first transmission. For example, the characteristic may include an indication of transmit power over time, network conditions over time, user behavior over time, application type over time, application behavior over time, whether voice and / or data is being transmitted over time, the type of data being transmitted over time, the priority or category of transmissions over time, antenna usage over time, sensor information over time, etc. In some aspects, the pattern may include periodic characteristics of the characteristics over time, such as a periodic indication of past transmissions. In some respects, certain patterns can be interpreted as "fingerprints," which indicate the specific environment in which the UE is located or the specific scenario / user conditions for the UE.

[0103] In box 604, the UE can determine the transmit power for one or more second transmissions based at least in part on a pattern and RF exposure limits. As further described herein, the UE can associate a pattern with an upcoming transmission, a transmission time associated with the upcoming transmission, the transmit power for the upcoming transmission, and / or a transmit power limit associated with RF exposure limits. For example, a transmit power pattern can instruct the UE to transmit in periodic bursts during certain time periods of the day. When an upcoming transmission aligns with the periodicity of past bursts, the UE can determine the transmit power for the upcoming transmission based on the pattern associated with the past bursts. In some respects, the UE can periodically store patterns (e.g., in memory 282, or in memory tightly coupled to processor 280 or data machine) as characteristics in memory and retrieve the pattern used to determine the transmit power in box 604.

[0104] In some respects, the determined transmit power is at or near the P limit unless it is determined, based on the pattern obtained in box 602, that additional RF exposure margin may be available. If the UE determines that additional margin may be available, the UE may determine a transmit power higher than the P limit (e.g., up to P max). The determination to transmit at a higher transmit power may also be based on one or more other factors or patterns. For example, a higher transmit power may be used when margin may be available, and it may be further determined that the UE is at the edge of a community or may be traveling into that area, or that margin may be available and information with a higher priority is being transmitted. In some respects, defaulting to a transmit power at or near the P limit and selectively increasing the transmit power may increase the likelihood of transmitting at the P limit (which may, for example, increase throughput and / or reliability) and / or reduce the amount of time spent transmitting at lower or backoff power (e.g., to comply with exposure limits). In box 604, the UE may determine a transmission mode (e.g., as described with respect to Figures 5A-5C), and based on and / or in accordance with the determined transmission mode, the transmit power may be determined to be at or near (e.g., below) the P limit or above the P limit (e.g., increased to above the P limit).

[0105] In box 606, the UE may transmit one or more second transmissions at a determined transmit power. For example, the UE may transmit a transmission to a base station (e.g., BS 110a) at a determined transmit power. In some cases, the UE may transmit to another UE via a sidelink channel.

[0106] The modes at boxes 602 and 604 may include one or more modes associated with the first transmission. In some aspects, the modes may include at least one of transmit power mode, user behavior mode, antenna usage mode, application type, application mode, wireless network mode, transmission type or priority mode, or sensor information and other types of information and / or modes. The transmit power mode may include transmit power over time (e.g., transient transmit power as a function of time), for example, over a time window or over a set of time windows. In some cases, if the average power from the transmit power mode is greater than or equal to a determined threshold (e.g., the threshold is less than or equal to P limit), the UE may consistently limit the power to a lower power level (e.g., P limit or lower). Otherwise, the UE may allow higher transient transmit power (> P limit) within a time window. That is, the average power from the transmit power mode may indicate how to determine the transmit power used for the second transmission. As an example, assume that the average power from the transmit power mode is less than half of the average transmit power level (e.g., P limit). This can indicate that the UE is likely to transmit very little uplink or sidelink traffic currently and / or in the near future, and that transmit power can be safely increased to comply with RF exposure limits. In some cases, transmit power patterns can indicate the duration of a transmission, and the duration can be used to determine transmit power. For example, if the transmit power pattern indicates that the transmission time of an upcoming transmission may be relatively long (e.g., the transmission time may be longer than the time window associated with RF exposure limits) and / or consistent uplink transmissions may persist over the time window, the transmitter can allocate a lower power level to the upcoming transmission (e.g., P limit, where P limit...). <P max)。

[0107] In some respects, the time window used to determine the pattern can be separate from another time window associated with RF exposure restrictions (e.g., time window (T) in Figures 5A and 5B). For example, the time window used for the pattern may include information about transmissions prior to the time window used to calculate the current RF exposure. In some respects, such prior information may be seconds, minutes, hours, days, or more prior to the window used to calculate the current RF exposure. In some respects, the time window used for the transmit power pattern may have the same or different duration as the time window associated with the current RF exposure restriction. The transmit power pattern may include one or more transmit powers over one or more time windows associated with the RF exposure restriction. As an example, the time window used for the transmit power pattern may have a duration of one or more seconds, one or more minutes, one or more hours, or one or more days. The UE can use the transmit power pattern associated with past transmissions to identify when an upcoming (future) transmission will occur, and the UE can determine the transmit power for the upcoming transmission based on the transmit power pattern (and RF exposure compliance).

[0108] In some respects, transmit power patterns can indicate rolling or moving average transmit power over time intervals, which can be separated from a time window associated with RF exposure limits. The average transmit power can be used to select an upper limit (cap) for transmit power. For example, a UE can use a specific algorithm associated with RF exposure limits to determine potential transient transmit power, and the UE can limit the determined potential transient transmit power to a level that is the reciprocal of past transmit power used (e.g., rolling average transmit power over the past X seconds), where "X" can be less than the time window associated with RF exposure limits. This reciprocal can be effective in adjusting transmit power in scenarios of transmission bursts (e.g., as depicted in Figure 5A) or continuous transmissions (e.g., as depicted in Figure 5B). In some respects, an upper limit for transmit power based on average transmit power, as described herein, can indicate changes in network duty cycle over time, low or high transmit power, and / or user behavior. The upper limit for transmit power as described herein can be applied to frequency division duplex (FDD) and / or time division duplex (TDD) schemes. The upper limit of transmit power as described herein may take into account near, medium and / or far community power levels and / or user behavior (e.g., burst use vs. continuous use).

[0109] An example formula for determining the upper limit of transmit power in a single transmission scenario is as follows: (9) in MTPL is the upper limit level of transmit power for a single transmission; MTPL is the potential transient maximum transmit power level determined according to a specific algorithm for an RF exposure time window; prev.usage can be the minimum of the normalized average transmit power over X seconds (e.g., average transmit power over X seconds / P limit) and unit 1 (i.e., 1, normalized for P limit / P limit) (e.g., the lowest value therein); and P limit can be the maximum average transmit power corresponding to the RF exposure limit averaged over time window T. Under equation (9), if the average transmit power for the most recent history over X seconds is zero, for example in a burst traffic scenario, MTPL' can be equal to MTPL and has no upper limit, because This will be very high. Therefore, MTPL' can initially be equal to P max. In continuous transmission scenarios, MTPL' can also be equal to MTPL at the start of transmission and has no upper limit because there is a lack of previous transmission history in transmit power mode. As the UE continues to transmit, the upper limit increases. (And therefore the transient transmit power) will begin to decrease and stabilize at the P limit, because If the term is less than or equal to the MTPL term, and the transmit power can be less than the P limit near the end of the time window, because the MTPL term is less than... item.

[0110] The following is an example formula for determining the upper limit of transmit power in a dual-transmission scenario: Where "pri" represents the parameters used for the primary transmitting radio, "sec" represents the parameters used for the secondary transmitting radio, and num_Tx represents the total number of active transmitting radios, which is 2 in this example. Active transmitting radios can refer to (multiple) transmitting antennas and / or (multiple) antenna modules, including antenna arrays, which will transmit simultaneously during the second transmission.

[0111] The following is an example formula for determining the upper limit of transmit power in a multi-transmission scenario: Where i is the index of a specific radio among multiple radios.

[0112] Regarding operation 600, the determination of the transmit power at box 604 may include determining a second transmit power (e.g., based at least in part on a normalized average transmit power over a time interval (e.g., prev.usage), which may be less than a time window associated with RF exposure limits. The UE can select a third transmit power as the minimum of the first and second transmit powers, for example, as described herein with respect to equation (9). The UE can determine the transmit power for one or more second transmissions such that the transmit power is less than or equal to the third transmit power. The second transmit power can be based at least in part on the reciprocal of the normalized average transmit power over past time intervals (e.g., The second transmit power can be the product of the maximum average power corresponding to the RF exposure limit (e.g., P limit) and the reciprocal of the minimum value of the normalized average transmit power in units (e.g., ...). ).

[0113] In a multi-transmission scenario, determining the transmit power at block 604 may include determining a first transmit power for each of the multiple radios and determining a second transmit power for each of the multiple radios, wherein the second transmit power may be based at least in part on the normalized average transmit power for the respective radio over a time interval. The UE may select a third transmit power for each of the multiple radios as the minimum of the first and second transmit powers for the respective radios. The UE may determine the transmit power for one or more second transmissions such that the transmit power for each of the multiple radios is less than or equal to the third transmit power for the respective radio.

[0114] The determination of the second transmit power may include, at least in part, determining the fourth transmit power based on the product of the maximum average power corresponding to the RF exposure limit for the respective radio and the reciprocal of the sum of the normalized average transmit power for multiple radios and the minimum value in units. The fourth transmit power can also be based on the ratio between the normalized average transmit power used for the corresponding radio and the total normalized average transmit power used for multiple radios. The UE can determine the fifth transmit power, the fifth transmit power (e.g., The maximum average power corresponding to the RF exposure limit is divided by the number of radios. The UE can base it on the maximum of the fourth and fifth transmit powers (e.g., (For example, the maximum value) to select the second transmit power.

[0115] In some respects, the time interval for the average transmit power used to select the transmit power ceiling can be dynamically updated (e.g., based on time-averaged exposure (or average transmit power) and / or network conditions). The time interval can be determined based on the following formula: (12) Where m can be the minimum value of X in seconds, n can be the maximum value of X in seconds, and average_exposure(t) can be the total average normalized exposure of all transmitting radios over a past time window (T) associated with the RF exposure limit (or the sum of the average transmit power / P limit from all radios for all past transmissions). In some cases, n can be smaller than the time window associated with the RF exposure limit. Different X values ​​can be applied to short burst transmissions and long transmissions. Equation (12) allows the UE to adjust the time interval as uplink and / or sidelink traffic changes over time. Furthermore, m and / or n can also vary from one transmitting radio to another based on the time averaging window associated with the radio. For example, if two transmitting radios are averaged over two different time averaging windows (e.g., a time window for sub-6 GHz radios and a separate time window for mmWave radios), the value of X (and in some cases, the value of m and / or n) can differ between the two radios.

[0116] Regarding operation 600, the determination of transmit power at box 604 may include adjusting the time interval of the normalized average transmit power based at least in part on the average power over a time window (T) corresponding to the RF exposure limit. In some aspects, the average power may be a rolling or moving average of the transmit power over the time window. The time interval adjustment may include selecting the maximum value of a first time interval (m) and a second time interval (n) that varies (e.g., is proportional to) the average power over the past time window, for example, as described herein with respect to equation (12). In some cases, the first time interval and the second time interval depend on the transmission frequency of one or more second transmissions. That is, the value of the first time interval and / or the value of the second time interval may vary depending on the transmission frequency. For example, the second time interval for sub-6 GHz transmissions may be higher than the corresponding second time interval for mmWave transmissions.

[0117] In some respects, the time interval can be adjusted based on one or more network conditions. For example, under poor network conditions (such as when the UE is at the edge of a community and / or in a mobile scenario), the time interval can be adjusted to a longer duration, such as n in equation (12), for example, because greater redundancy and longer transmissions are encountered under poor network conditions. Under ideal network conditions (such as when the UE is stationary and very close to the base station), the time interval can be adjusted to a shorter duration, such as m in equation (12), for example, because reduced redundancy and shorter transmissions are encountered under ideal network conditions. Regarding operation 600, the transmit power determination at block 604 may include adjusting the time interval of the normalized average transmit power based at least in part on one or more current network conditions, such as one or more of the parameters further described herein with respect to network modes.

[0118] In some respects, the upper limit on the maximum transmit power described herein can be implemented without altering the underlying algorithm or process for determining the MTPL, thus guaranteeing RF exposure compliance. In other words, since the original algorithm or process for the MTPL remains unchanged, the upper limit can be applied to any algorithm or process that generates the MTPL. In some respects, the algorithm or process for determining the MTPL operates separately or independently from the algorithm or process for determining the upper limit. For example, a first process can be performed to determine the transmit power that complies with RF exposure limits, and a second process can be performed independently to determine whether an upper limit is set for the determined transmit power. In some respects, the second process operates at a different layer (e.g., the application layer or other layers, such as in the Open Systems Interconnection (OSI) model) compared to the first process.

[0119] Determining the transmit power at block 604 may include determining a first transmit power (e.g., MTPL) and applying an upper limit to the first transmit power to determine a second transmit power (e.g., MTPL'), for example, as per equation (9) herein. The UE may determine the transmit power for one or more second transmissions such that the transmit power is less than or equal to the second transmit power.

[0120] In some respects, the UE can determine the transmit power in box 604 by selecting one of the following three options: (1) a transient transmit power determined for RF exposure compliance according to a specific algorithm (e.g., MTPL); (2) a transient transmit power and a transmit power based on a normalized average transmit power used for the radio over a time interval (e.g., ...). (3) the minimum of the transient transmit power and the minimum of the maximum average power (e.g., P limit) corresponding to the RF exposure limit, wherein the minimum operation ensures compliance with the RF exposure limit; and (4) the minimum of the transient transmit power and the maximum average power (e.g., P limit) corresponding to the RF exposure limit, wherein the minimum operation again ensures compliance with the RF exposure limit.

[0121] Regarding the determination of transmit power at operation 600, box 604, it may further include determining a first transmit power (e.g., MTPL) for one or more second transmissions based at least in part on time-averaged RF exposure over a past time window; and determining a second transmit power (e.g., based at least in part on normalized average transmit power for radio over a time interval). The UE determines a third transmit power (e.g., P limit), which is the maximum average power corresponding to the RF exposure limit. The UE can select a fourth transmit power as the minimum of the first and second transmit powers for radio, and a fifth transmit power as the minimum of the first and third transmit powers for radio. For example, depending on the mode described herein, the UE can select a sixth transmit power from the first, fourth, and fifth transmit powers. The UE can determine the transmit power for one or more second transmissions such that the transmit power is less than or equal to the sixth transmit power for radio.

[0122] In a multi-transmission scenario, the transmit power determination at box 604 may further include determining a first transmit power (e.g., MTPL i) for each of the multiple radios, wherein the first transmit power is based at least in part on the time-averaged RF exposure in a past time window; and determining a second transmit power (e.g., ...) for each of the multiple radios. The second transmit power is based at least in part on the normalized average transmit power of the corresponding radio over the time interval; and a third transmit power is determined for each of the plurality of radios (e.g., The third transmit power is the maximum average power (e.g., P limit) corresponding to the RF exposure limit divided by the number of radios. The UE can select a fourth transmit power for each of the radios as the minimum of the first and second transmit powers for that radio, and a fifth transmit power for each of the radios as the minimum of the first and third transmit powers for that radio. For example, depending on the mode as described herein, the UE can select a sixth transmit power for each of the radios among the first, fourth, and fifth transmit powers. The UE can determine that the transmit power for one or more second transmissions is such that the transmit power for each of the radios is less than or equal to the sixth transmit power for that radio.

[0123] Antenna usage patterns can indicate when a UE switches to a different transmission antenna and the duration over which a UE uses a particular antenna for transmission. For example, a UE can identify when to switch to a different transmission antenna based on antenna usage patterns, and the UE can perform such a switch for a second transmission to obtain more RF exposure margin (e.g., if the target antenna for the antenna change is not near human tissue) or determine that another antenna with more RF exposure margin may be available for use at a later time, so additional power can be allocated to the current transmission where the risk of exceeding RF exposure limits in the future is relatively low.

[0124] Certain aspects of this disclosure may provide an apparatus and / or technique for setting a transmit power ceiling for a particular radio, for example, based on antenna usage associated with other radios, wherein the transmit power ceiling is separate from the average power limit associated with RF exposure restrictions and the maximum transmit power supported by the radio. That is, in a multi-radio transmission scenario, antenna usage over time for one or more radios (e.g., sub-6 GHz radios) can be used to determine the transmit power for another radio (e.g., mmWave radio). In ensuring RF exposure compliance, the total available RF exposure margin based on the past usage of all radios can be further divided into individual margins for each radio based on radio priority and / or desired margin. As further described herein, the margin for a particular radio can be adjusted over time, for example, based on the usage rate of other radios. If a radio is expected to maintain consistent performance over time, the RF margin can be ceilinged based on the past average usage rate of other radios. For example, it is assumed that the past usage rate of a frequency range 1 (FR1) (below 6 GHz) radio indicates that the FR1 radio is using a relatively small portion of the total RF exposure margin. In this scenario, the UE can allocate a transmit power cap for the frequency range 2 (FR2) (mmWave) radio to provide consistent performance based on the past usage of the FR1 radio. As an example, the UE could allocate a transmit power cap that dedicates a significant portion of its RF exposure margin (e.g., 90%) to the FR2 radio.

[0125] In multi-transmission (e.g., when multiple radios are used for concurrent transmission) and / or multi-radio scenarios (e.g., when a wireless communication device is equipped with multiple radios), the total available RF exposure margin can be determined according to the following formula: A = 100% - (radio 1 + ... + radio i) Past average usage rate (13) Where A is the total available RF exposure margin, and the past time average utilization can be the sum of the time average transmit power of each radio over a specific time interval, such as a portion of a time window associated with RF exposure limits, the entire time window, or a time interval longer than a time window (e.g., multiple time windows, one hour or more hours, or one day or more days).

[0126] The individual RF exposure margin allocated to each radio can be determined using the following formula: Balance 1 = x 1 * A (for radio 1), Remainder 2 = x 2 * A (for radio 2), ..., Balance i = xi * A (for radio i), (14) Where x1 to xi are factors used to allocate a portion of the total available RF exposure margin to the respective radio, x1 + x2 + ... + xi = 1. In some respects, the UE can adjust the values ​​of x1 to xi for one or more radios among the radios according to one or more criteria. For example, the x value for a particular radio can be determined based on the likelihood of that radio being used for transmission (such as based on the application associated with the radio, data buffer, traffic model, or pattern). In some cases, the x value for a particular radio can be determined based on priority, such as the priority of a particular channel and / or RAT (e.g., LTE vs. 5G) relative to another channel and / or RAT, where a radio can be associated with a particular channel. Channel priority can be based on the transmission duty cycle associated with the channel. In the context of an application or service, suppose one radio is transmitting content for an instant video call, while another radio is transmitting data. In this case, for example, the UE can assign priority to the radio serving the video call, which may result in a larger portion of the RF margin (i.e., a larger value of x) being allocated to that radio.

[0127] The upper limit of transmit power for a specific radio (e.g., radio k) can be determined according to the following formula: cap_radio k = 100% - average usage of remaining radios over past time (radio 1 + radio 2 + ... + radio k-1 + radio K+1) (15)

[0128] The RF margin allocated to radio k can be determined according to the following formula: minimum(xk*A,cap_radio k) (16)

[0129] Operation 600 may also involve the UE determining a transmit power cap for a particular radio, as described herein. In some aspects, antenna usage patterns may include usage patterns for each of a plurality of radios (such as transceivers 254a-254r of Figure 2). In block 604, the UE may determine an overall available RF exposure margin based on the usage patterns for each of the plurality of radios, for example according to equation (13). In some aspects, the UE may determine the difference between the maximum available utilization (e.g., 100%) and the sum of usage patterns for the radios (e.g., the sum of average transmit power). In certain cases, such as single-transmission scenarios (e.g., when only a single radio is used for transmission) and / or single-radio scenarios (e.g., when a wireless communication device is equipped with a single radio), the UE may determine a transmit power cap for the radio based on the usage patterns for the radio, and the UE may determine the transmit power for one or more second transmissions based at least in part on the transmit power cap. In this case, the transmit power cap may be less than the maximum transmit power (P max) supported by the UE and greater than the average power limit (P limit) associated with the RF exposure limit (P limit ≤ P cap ≤ P max).

[0130] The UE can, for example, allocate RF exposure margin to each radio based on the total available RF exposure margin according to equation (14). In some aspects, the UE can allocate a portion of the total available RF exposure margin to each radio as the RF exposure margin of the respective radio. In some cases, the UE can apply a priority order to a specific radio when allocating RF exposure margin to a particular radio. That is, the UE can allocate a proportion of the total available RF exposure margin to each radio based at least in part on a priority order associated with at least one of the radios. The priority order and / or proportion can be associated with at least one of the frequency band, application, service, network conditions, or exposure scenario (e.g., head exposure, body exposure, limb exposure, or hotspot exposure) associated with the respective radio. That is, the UE can control the allocation of available RF exposure margin among multiple radios on an ad hoc basis by changing the values ​​of factors x1 to xi. In some aspects, the UE can adjust factors x1 to xi in conjunction with radio priority orders, which can change over time with application, network conditions, and / or usage scenarios (e.g., hotspot mode). In other words, priorities and proportions can be adjusted over time in response to changes in applications, services, network conditions, etc. For example, a UE can allocate a larger proportion of the total available RF exposure margin to a specific radio, such as an mmWave radio, based on the operating frequency band of that radio. For example, suppose the UE has a total of four radios. In this example, the UE can adjust the factor xk of the mmWave radio to 0.5 and distribute the remaining RF exposure margin evenly among the remaining radios (e.g., 0.16).

[0131] The UE can, for example, determine the upper limit of transmit power (e.g., cap_radio k) for one of the radios based on the usage patterns for each of the other radios according to equation (15). In some respects, the UE can determine the upper limit of transmit power as the difference between the maximum available utilization (e.g., 100%) and the sum of the usage patterns for each of the other radios (e.g., the sum of the average transmit power for the other radios).

[0132] The UE may determine the transmit power for the second transmission based at least in part on the transmit power cap and the RF exposure margin allocated to one of the radios. For example, the UE may determine the transmit power to be less than or equal to the RF margin allocated in equation (16). In some cases, the UE may adjust the transmit power cap in response to changes in usage patterns for the radios (in a multi-radio scenario) and / or changes in the radios (in a single-radio scenario). For example, suppose the usage pattern for the sub-6 GHz radio indicates that more transmit power can be allocated to the mmWave radio, for example, due to reduced usage of the sub-6 GHz radio. In response to the updated usage pattern, the UE may increase the transmit power cap allocated to the mmWave radio based on the usage pattern for the other radios.

[0133] In some respects, the UE can adjust its transmit power cap in response to changes in the transmission scenario associated with the radio. For example, the transmission scenario can be associated with certain radios being used simultaneously, exposure scenarios (head exposure, body exposure, limb exposure, etc.), and / or the area where the UE is located.

[0134] In some respects, the UE can adjust the transmit power cap based at least in part on a traffic model. The UE can develop a traffic model associated with a radio, where the traffic model indicates when to adjust the transmit power cap. For example, the traffic model could specify that a higher transmit power cap can be allocated to a particular radio during a certain time of day.

[0135] In several aspects, the usage pattern for each of the multiple radios can include the average transmit power over past time intervals associated with the respective radio. For example, the UE can determine the average transmit power for each of the radios over a past time window associated with RF exposure limits.

[0136] In box 606, the UE may transmit a second transmission at the transmit power limit for a first portion of a time window associated with RF exposure restrictions, and transmit a second transmission at a different transmit power less than the transmit power limit for a second portion of the time window, for example, as described herein with respect to Figure 9B.

[0137] User behavior patterns can indicate when a user uses or does not use the UE for wireless communication. User behavior patterns can include one or more times associated with when and / or how a user uses or does not use the UE for wireless communication. For example, if a user is likely to generate transmissions in periodic / aperiodic bursts or continuously (e.g., over long durations), the user behavior pattern can indicate when the user typically avoids using the UE, such as during sleep, exercise, or other activities. During such periods, based on the assumption that additional transmissions are unlikely to be initiated by the user, the UE can allow transmit power to exceed the average power level (e.g., P limit) within the time window used for RF exposure compliance. That is, during such periods of potentially low or no usage indicated by the user behavior pattern, the UE can determine that continuous transmissions are unlikely (e.g., since the user is unlikely to initiate such transmissions) and therefore allow transmissions at transient power levels above the P limit (e.g., at P max). In contrast, during periods when the user typically uses the UE (e.g., when the user wakes up in the morning, during lunch, or in the evening), the UE can limit transmissions to transient power levels above the P limit, for example, based on the assumption that additional transmissions are likely to be initiated by the user and therefore most of the transmission window is likely to be occupied by transmissions at or near the P limit. That is, during periods when uplink activity is more likely, as indicated by the user behavior pattern, the UE can set its transmit power to be less than or equal to the maximum average transmit power level P limit. Regarding operation 600, the transmit power determined in block 604 can be adjusted for the second transmission based on the user behavior pattern.

[0138] Application patterns can indicate various characteristics associated with an application (e.g., a mobile software application) that generates data for transmission. In some aspects, an application pattern can include the behavior of the application, which can indicate at least one of one or more transmission times or one or more transmission powers over time associated with the application. For example, if the application pattern indicates that the application generates data for transmission in periodic bursts, the UE can associate the periodic bursts with a time window associated with RF exposure limits and determine the transmission power available for application transmission based on the duration of the periodic bursts. In some cases, the pattern can indicate the type of application associated with the application pattern. That is, the application type can indicate the kind of application that generates data for transmission. For example, the application type can be an indication of whether the application is a social media application, a messaging application, an email application, a video calling application, a video conferencing application, a video game, a video streaming application, a navigation application, etc. In some aspects, the UE can prioritize the transmission power for one or more applications based on the application type. The UE can identify the application type for a second transmission, for example, based on the application type pattern and / or an explicit indication from the application processor (e.g., controller 280) adopted by the UE, and the UE can determine the transmission power for the second transmission based on the application type that takes precedence over other application types. For example, compared to other applications, the UE can allocate more transmit power to data streaming audio and / or video applications (such as video calling applications or video conferencing applications). In some scenarios, when the UE has determined that another higher priority application will transmit data within the same exposure time window, the UE can prohibit the lower priority application from transmitting at a transient power level higher than the maximum average power level (e.g., P limit).

[0139] A radio network mode can indicate various aspects of radio network conditions. A radio network mode can include at least one of the following: channel quality between the UE and a receiving entity (e.g., one or more base stations or other UEs); modulation coding scheme (MCS) associated with one or more first transmissions; coding rate (e.g., proportion of non-redundant data flow) associated with one or more first transmissions; period associated with one or more first transmissions; duty cycle associated with one or more first transmissions; or mobility scenario, such as an indication of the UE's mobility during one or more first transmissions. In some cases, a radio network mode can indicate past radio conditions (such as channel quality, MCS, coding rate, etc.) encountered by the UE over a period of time. The UE can use past radio conditions to predict future radio conditions and allocate transmit power accordingly for such radio conditions. For example, suppose the UE identifies a mobility scenario (such as commuting to or from work) during certain times of the day. In this case, the UE can allocate specific transmit power to suit the mobility scenario. For example, when the UE identifies a community edge (e.g., poor radio conditions) based on the mobility scenario indicated by the radio network mode, the UE can allow transmit power equal to or higher than the maximum average transmit power limit (P limit). In contrast, when the UE identifies that it is actually stationary, the UE can allocate a transmit power less than or equal to the maximum average transmit power limit (P limit) for the second transmission based on the first transmission, since it is assumed that the radio conditions will not change adversely (e.g., in a mobile scenario).

[0140] Other parameters associated with wireless network conditions may also be included in the wireless network mode, such as community identifier, number of aggregated component carriers, number of MIMO layers, bandwidth, subcarrier spacing, frequency range (e.g., FR1 or FR2 under 5G NR), etc. In some aspects, channel quality may include path loss, channel quality indicator, signal-to-noise ratio (SNR), signal-to-interference-to-noise ratio (SINR), signal-to-noise plus-distortion ratio (SNDR), reference signal received power (RSRP), and / or received signal strength indicator (RSSI).

[0141] Transmission type or priority mode can indicate what types of transmissions have been sent and / or their relative priority. For example, the mode may include information about whether a voice call or data has been transmitted and its mode. This mode can distinguish whether voice and data are being transmitted simultaneously and / or whether a certain type of communication (e.g., voice) might be initiated while another type of communication (e.g., data) is being transmitted. The mode may include relative transmission priorities, such as voice having a higher priority than data, or certain data types (e.g., Voice over Internet Protocol (VoIP), video conferencing, certain types of streaming) having a higher priority than other types of data (e.g., email or file upload). In some such cases, when the mode indicates that another transmission with a higher priority may be required, or when the type of information that may be transmitted typically involves a long transmission time (e.g., greater than the exposure time window) and / or a relatively consistent amount of power over time, the UE will not allocate or is unlikely to allocate transient transmit power above the maximum average power level (P limit). In some respects, one or more of the above modes (e.g., antenna usage mode, application mode, and / or transmission type mode) can be used to determine whether to use 4G service or 5G service and / or to transmit in the sub-6GHz band or mmWave band.

[0142] Sensor information may include various sensor data or information generated by the UE. Sensor information may include RF exposure sensor information over time, such as the distance of the UE from various human body parts over time, or when the UE is placed away from human tissue (e.g., in a hotspot scenario, or while being charged). The UE can use the RF exposure sensor information to adjust the maximum average transmit power level (e.g., P limit) associated with RF exposure limits. For example, if sensor information indicates that the UE will approach human tissue (e.g., when the UE is typically placed in a user's pocket), the UE may adjust (e.g., decrease) the maximum average transmit power level (P limit) to conform to that RF exposure scenario. Conversely, if sensor information indicates that the UE will not approach human tissue, the UE may adjust (e.g., increase) the maximum average transmit power level (P limit) to conform to that other RF exposure scenario. Sensor information may include at least one of the following: indication of the UE approaching a non-human object, indication of the UE being in free space, indication of the user's usage scenario, indication of the UE's usage state, or indication of when an antenna switch occurs at the UE. In some respects, user usage scenario can indicate which part of the user's body the UE is near (e.g., hand, head, or body). Usage status can indicate whether the UE is being used near human tissue, for example, the UE is being used as a hotspot rather than near human tissue.

[0143] In some aspects, at box 606, the UE can use various models to determine transmit power based on patterns. The UE can use machine learning to predict / learn future transmissions based on patterns. For example, the UE can use machine learning to predict / learn future network / radio conditions (e.g., a route from home to work) based on past network conditions and / or user behavior, represented, for example, by wireless network patterns and / or user behavior patterns. That is, the UE can use machine learning to map upcoming user behavior (e.g., data bursts or large data packets) to current network conditions (e.g., stationary), or to map current user behavior to upcoming network conditions (e.g., in a mobile scenario), or both. In some aspects, the UE can use machine learning to predict other characteristics associated with upcoming transmissions based on patterns (e.g., antenna switching, sensor information, application type, and / or behavior, etc.). In some aspects, the characteristics predicted using patterns can be generated using various models or estimations, such as machine learning, artificial intelligence, neural networks, regression analysis, etc.

[0144] In some aspects, in box 606, the UE may determine the transmit power at least partially based on patterns using machine learning. In some cases, the UE may use machine learning to generate upcoming user behavior based on patterns (e.g., user behavior patterns) and determine the transmit power based on the upcoming user behavior and current network conditions. In some aspects, the UE may use machine learning to generate upcoming network conditions based on patterns (e.g., wireless network patterns) and determine the transmit power based on current user behavior and upcoming network conditions. In some cases, the UE may use machine learning to generate upcoming network conditions and upcoming user behavior based on patterns (e.g., both wireless network patterns and user behavior patterns) and determine the transmit power based on the upcoming network conditions and upcoming user behavior.

[0145] In some respects, the UE can correlate a pattern with a transmit time associated with one or more second transmissions and compare the transmit time with a time window associated with an RF exposure limit. The UE can determine the transmit power based on the comparison. For example, assuming the pattern is associated with a short transmit time of an upcoming transmission that is less than the time window associated with the RF exposure limit, the UE can allocate a transmit power greater than the maximum average transmit power level (P limit) and / or less than the maximum supported transmit power (P max) for such transmissions.

[0146] In some respects, RF exposure limits may comply with limits set by regulatory / standards bodies (e.g., the U.S. Federal Communications Commission (FCC); Innovation, Science and Economic Development Canada (ISED); or the International Commission on Non-Ionizing Radiation Protection (ICNIRP) standards of the European Union). RF exposure limits may include SAR limits and / or PD limits for various frequency ranges. In some respects, the UE may determine in box 604 that the transmit power complies with the RF exposure limits. For example, when communicating via multiple wireless technologies, the UE may compare a normalized distribution of a combination as described herein with respect to Figure 4 with RF exposure compliance thresholds for multiple technologies. RF exposure limits may be averaged over time within a specified time window, such as 4 seconds for transmit frequencies between 24 GHz and 42 GHz, 100 seconds for transmit frequencies less than 3 GHz, or 360 seconds for transmit frequencies less than 6 GHz.

[0147] Figure 7A is a diagram 700A illustrating an example mode 702 for determining one or more transmit powers over time according to certain aspects of this disclosure. In this example, mode 702 has two periodic first transmissions 704, each of which has a duration 706, which is less than a time window (T) associated with an RF exposure limit. The UE can determine from mode 702 that second transmissions 708, 710 are likely to be transmitted in an upcoming time window. Based on mode 702, the UE can determine the transmit power for the second transmissions 708, 710. For example, the UE can identify that the first transmission 704 has a transmission time (i.e., duration 706) that is less than the time window (T). Thus, for example, based on the mode also indicating that the UE may be experiencing a mobility scenario, the UE can allocate transmit power greater than the P limit (such as P max) to the second transmission 708. For example, based on the mode also indicating that the UE may be stationary, the UE can allocate transmit power to the second transmission 710 at a transmit power closer to the P limit. The UE can determine whether to allocate a transmit power less than, equal to, or greater than the maximum average transmit power level (P limit) based on patterns such as past network conditions, user behavior, and application type. In various respects, mode 702 can be (or derived from) one or more different modes, such as transmit power mode, user behavior mode, application mode, wireless network mode, and / or sensor information mode. Although two time windows are used to determine the mode in Figure 700A, it should be understood that more or fewer time windows (or other durations not based on exposure time windows) can be used as the basis for the mode.

[0148] Figure 7B is a diagram 700B illustrating another example mode 722 for determining one or more transmit powers over time according to certain aspects of this disclosure. In this example, mode 722 has a periodic transmission 724, the duration of which is 726, which is greater than the time window (T) of RF exposure. The UE can determine, based on mode 722, that an additional transmission that will consume most of the available power in the upcoming time window is likely to be transmitted in the upcoming time window. Based on mode 722, the UE can determine the transmit power for a second transmission 728. For example, the UE can identify that the first transmission 724 has a transmission time greater than the time window (T) (i.e., duration 726). Thus, the UE can allocate transmit power to the second transmission 728 that is equal to or less than the maximum average transmit power level (P limit). In some cases, the UE can identify that an upcoming transmission may only overlap with a portion of one or more time windows (T), such that additional transmit power 730 can be allocated to the second transmission in one of the time windows (T).

[0149] Figure 8A is Figure 800A illustrating an example mode 802 according to certain aspects of this disclosure, which is used to determine one or more transmit powers over time for short transmissions (e.g., transmissions with a duration less than the RF exposure time window, also referred to as "burst transmissions"). In this example, mode 802 may indicate the average transmit power over time interval 804. In some cases, mode 802 may include a rolling or moving average of the transmit power. The UE may, for example, use equation (9) to select a new upper limit for the transmit power based on mode 802. Since the average transmit power within mode 802 is less than P limit, the UE may revert to using MTPL as the maximum transmit power available for transmission (e.g., P max). The UE may allocate transmit power equal to or less than MTPL for transmission 806, where MTPL may be equal to P max.

[0150] Figure 8B is Figure 800B illustrating other example modes 822a-c according to certain aspects of this disclosure, example modes 822a-c being used to determine one or more transmit powers over time for long-duration transmissions (e.g., transmissions with a duration greater than an RF exposure time window). In this example, transmission 808 may span multiple time windows (T) associated with an RF exposure limit. At the beginning of transmission 808, the average transmit power over time interval 804 of the first mode 822a is zero, allowing the UE to select P max as the maximum transmit power, for example, under equation (9). Due to the reciprocal upper limit, the transmit power may decay at a rate that is a function of the reciprocal of the average transmit power, and the transmit power may stabilize at P limit as the average transmit power over the time interval approaches P limit. In subsequent transmissions (e.g., during the same time window T), the average transmit power may be equal to P limit over time interval 804 of the second mode 822b. In this case, the UE can effectively select P limit as MTPL and The minimum value in, for example, because MTPL is greater than In later transmission scenarios (e.g., during the same time window T), the average transmit power may still be equal to the P limit within the time interval 804 of the third mode 822c. However, the MTPL can be less than the P limit to ensure compliance with RF exposure limits, such that the UE selects the MTPL for the remainder of the time window (T) as the maximum transmit power available for transmission 808.

[0151] In some respects, the transmit power selected by the UE at the start of the subsequent time window (T) is less than the transmit power selected at the start of transmission 808. The average transmit power of the first mode 822a is zero in the example shown in Figure 8B, while the average transmit power between the end of interval 804 corresponding to mode 822c and the start of the subsequent time window (T) is shown as non-zero (e.g., between zero and P limit). Therefore, the transmit power selected by the UE at the start of this subsequent time window (T) (e.g., according to equation (9)) can be less than P max (but greater than P limit). Furthermore, the average transmit power selected at the end of this subsequent time window (T) can be closer to P limit than the average transmit power selected at the end of the first time window. This can cause the transmit power selected by the UE at the start of even later transmission windows (T) (e.g., represented by the rightmost peak in Figure 8B) to also be closer to P limit. Therefore, it can be observed that, in some respects, for continuous / long-duration (e.g., with a duration greater than the time window) transmissions, the transmit power selected by the UE will be closer to P limit.

[0152] While certain aspects of this disclosure are described herein to facilitate understanding regarding the use of patterns representing historical behavior or conditions to determine transmit power that meets RF exposure limits, the UE may also apply aspects of this disclosure using current conditions (e.g., current radio conditions and / or data buffers) to validate, adjust, or compensate for pattern-based transmit power determination. For example, the UE may determine possible or expected usage or transmit power in the current or future time window based on patterns from past information, and may subsequently compare the possible or expected usage or transmit power with data stored in a transmission buffer. In some such aspects, the UE may determine a first power for current or future transmission, and if the difference between the data in the transmission buffer and the expected usage is greater than a first threshold, or if it involves an amount of power to be transmitted that differs from the expected transmit power by more than a second threshold, the first power may be adjusted before setting the transient transmit power.

[0153] It should be understood that determining transmit power based on patterns (e.g., transmit power patterns, user behavior patterns, etc.) offers various advantages. In some cases, transmit power determination allows the UE to allocate transmit power according to patterns adapted to historical conditions and / or RF exposure limitations. Using this self-adjusting transmit power scheme, the UE can be able to provide the desired transmit power for specific user behaviors, network conditions, application types, etc.

[0154] Figure 9A is Figure 900A illustrating an example antenna usage mode 902 for a first radio according to certain aspects of this disclosure. In this example, antenna usage mode 902 for the first radio shows that a first transmission 904 can be transmitted in a burst less than the time window T0 associated with RF exposure limits. In this case, this can leave an additional RF exposure margin for another radio (e.g., a second radio).

[0155] Figure 9B is a figure 900B illustrating an example of setting a transmit power cap (P cap) for a second radio based on the antenna usage pattern shown in Figure 9A according to certain aspects of this disclosure. In this example, the UE can determine the transmit power cap (P cap) for the second radio according to equation (15) and / or equation (16). In some cases, after a certain time offset (t) from an instance of time window T0 in Figure 9A, the UE can transmit a second transmission 906 at the transmit power cap during the first portion 908 of time window T1, and transmit the second transmission 906 at a different transmit power less than the transmit power cap during the second portion 910 of time window T1, to keep the average transmit power within the P limit associated with the RF exposure limit. Since time window T0 can represent the time of a past usage pattern, T1 can be time-offset (t) from T0. In some aspects, the transmit power cap can promote a consistent performance level of the second radio during the time window associated with the RF exposure limit.

[0156] A transmit power cap can be applied to a single-radio transmission scenario (e.g., where a single radio is transmitting) or a multi-radio transmission scenario (e.g., where multiple radios are transmitting simultaneously). The cap P_max can extend a portion of the time window in which the wireless communication device is transmitting above P_limit. For a single radio, where P_cap is set to be less than P_max, the transmit power can be transmitted at the P_cap level for a longer period before encountering an exposure limit compared to transmission at the P_max level. Similarly, for a multi-radio scenario, a portion of the RF exposure margin (x_k*A) can be capped for radio k, and the P_cap for radio k can be determined based on (x_k*A*P_limit_radio_k), where P_limit is the average transmit power associated with the RF exposure limit. While maintaining RF exposure compliance, transmit energy based on examples of transmission times.

[0157] In some aspects, the UE can consider future conditions (such as transmission time and / or radio conditions) when determining the transmit power for RF exposure compliance. Various aspects of this disclosure provide techniques and apparatus for determining transmit power based on the transmit time associated with data and / or radio conditions and / or switching between various transmission modes described herein while ensuring RF exposure compliance. In some aspects, the transmit time can be derived from the size associated with the data (e.g., data buffer size) and the current (or predicted future) data rate. As an example, if the data buffer size is large (e.g., the transmit time is greater than the time window associated with the RF exposure limit), the transmitter can operate in peak mode (e.g., as described herein with respect to Figure 5B) to enable continuous transmission at an average power level (e.g., P limit). If the data buffer size is small (e.g., the transmit time is less than the time window associated with the RF exposure limit), the transmitter can operate in time-averaged mode (e.g., as described herein with respect to Figure 5C) and transmit at maximum power if necessary to complete the transmission, then transmit at a standby power.

[0158] The various techniques described in this paper for ensuring RF exposure compliance can achieve desired transmit power and / or desired power consumption for data transmission. Desired transmit power can provide desired uplink / sidelink performance, such as ideal data rates, carrier aggregation, and / or connectivity at the community edge.

[0159] Figure 10A is a flowchart illustrating an example operation 1000A for wireless communication according to certain aspects of this disclosure. Operation 1000A can be performed, for example, by a UE (e.g., UE 120a in wireless communication network 100). Operation 1000A can be implemented as a software element executed and running on one or more processors (e.g., controller / processor 280 of Figure 2). Furthermore, the transmission of signals by the UE in operation 1000 can be achieved, for example, via one or more antennas (e.g., antenna 252 of Figure 2). In some aspects, the transmission and / or reception of signals by the UE can be achieved via a bus interface of one or more processors (e.g., controller / processor 280) that acquires and / or outputs signals.

[0160] Operation 1000A may begin at box 1002, where the UE may acquire data for a transmission to a receiving entity (e.g., BS 110a or another UE) and the radio conditions associated with that transmission. In box 1004, the UE may determine the transmission time associated with the data based at least in part on the radio conditions. In box 1006, the UE may transmit a signal indicating the data to the receiving entity at a transmission power at least in part based on the determined transmission time and RF exposure limits. In some aspects, box 1004 may alternatively or additionally include selecting a mode from multiple transmission modes based on radio conditions (or one or more other conditions) and / or data, and box 1006 may alternatively include transmitting a signal indicating the data to the receiving entity at a transmission power at least in part based on the selected transmission mode and RF exposure limits. In some aspects, the transmission mode may be selected based on an application or service, such as video calling, voice calling, live video streaming, online gaming, etc. For example, in a video call, a transmission mode can be selected to transmit consistently regardless of radio conditions or other conditions (such as peak mode or similar peak mode described herein with respect to Figures 11A-11C).

[0161] In some respects, the UE can determine the amount of transmission time to be used to transmit data to the receiving entity in order to select a transmission mode (e.g., time-averaged mode or peak mode). The determination of the transmission time can be derived using various factors such as a given transmit power, data size or buffer size, and data rate, which can be derived using current radio conditions. The data rate can depend on various factors or conditions, such as the channel quality between the UE and the receiving entity, the path loss between the UE and the receiving entity, the period and / or duty cycle associated with the transmission to the receiving entity, the modulation coding scheme (MCS), the coding rate (e.g., the proportion of non-redundant data flows), the number of aggregated component carriers, the number of MIMO layers, bandwidth, subcarrier spacing, frequency range (e.g., FR1 or FR2 under 5G NR), etc. For example, a high MCS (e.g., 256QAM), high transmit power (e.g., P max), high duty cycle, low path loss, and small data size may result in a relatively short transmission time (e.g., less than the transmission time of the time window associated with RF exposure limits). In some respects, radio conditions can be obtained at box 1002 using a processor and / or data unit, such as controller 280 and / or data unit (modulator / demodulator) in transceiver 254.

[0162] Regarding Operation 1000A, radio conditions may include at least one of the following: channel quality between the UE and the receiving entity, MCS associated with transmission, coding rate associated with transmission, number of aggregated component carriers associated with transmission, number of MIMO layers associated with transmission, bandwidth, subcarrier spacing, frequency range associated with transmission, or period associated with transmission to the receiving entity. In some aspects, channel quality may include path loss, channel quality indicator, signal-to-noise ratio (SNR), signal-to-interference-to-noise ratio (SINR), signal-to-noise plus-distortion ratio (SNDR), reference signal received power (RSRP), and / or received signal strength indicator (RSSI). In some aspects, radio conditions may be determined corresponding to or based on the radio network mode described herein with respect to Figures 6-9B.

[0163] Radio conditions can be used to determine the data rate or throughput for transmitting data to a receiving entity. The data rate can be determined in megabits per second (Mbps). For example, a UE can determine the data rate associated with transmitting data to a receiving entity based on radio conditions, and the UE can determine the transmission time based on the data rate and the size associated with the data. In some respects, the UE can use formulas for approximate maximum uplink data rates specified in 3GPP standards (e.g., Specification 38.306, Section 4.1.2) to determine the data rate.

[0164] In some respects, the size associated with the data can be bytes, bits, or other units of computer / digital information. The size associated with the data can correspond to the size of a data buffer used for temporary storage of data for transmission. For example, the UE can determine the transmission time based at least in part on the buffer size associated with the data. In some respects, the UE can determine the transmission time based on the buffer size associated with the data (which may be referred to as the "upload data buffer size") and the data rate determined according to radio conditions. In some respects, instead of acquiring data in block 1002, the UE can acquire the size associated with the data, and the UE can determine the transmission time associated with the data based on the data rate and the data size.

[0165] In some respects, transmission time can be determined for various transmit powers, such as transient power limits (e.g., P max in Figure 5C) and average power (e.g., P limit in Figure 5B). As used herein, a transient power limit can refer to the maximum transmit power supported by the UE (e.g., P max) or other transmit powers above the average power. Average power can refer to the peak transmit power that can be maintained over the duration of a time window associated with an RF exposure limit (e.g., P limit) that conforms to the RF exposure limit. That is, average power can be an average power level corresponding to the RF exposure limit (e.g., consistent with regulatory requirements and / or device manufacturer settings, which are based on regulatory requirements but may be below them).

[0166] As an example, the transmission time can be selected from multiple transmission times associated with multiple transmission powers, where the multiple transmission powers can include the transmission power of the signal transmitted at box 1006. The multiple transmission times can include a first transmission time associated with a transient power limit supported by the UE (e.g., the maximum transmission power supported by the UE) and a second transmission time associated with an average power corresponding to an RF exposure limit. In some aspects, the first transmission time can be the duration spent by the UE transmitting data at a transient power limit (e.g., P max), regardless of any power reserve margin and RF exposure compliance, and the second transmission time can be the duration spent by the UE transmitting data at an average power (P limit).

[0167] Using the determined transmission time, the UE can select a transmission mode (e.g., time-averaged mode or peak mode) to ensure RF exposure complies with RF exposure limits. For example, time-averaged mode can be applied to shorter transmission times or bursts of traffic, allowing the UE to transmit at its maximum power (e.g., Pmax) while still maintaining RF exposure compliance and retaining a transmit power margin within the time window associated with RF exposure limits. Peak mode can be applied to transmissions with relatively long durations (e.g., transmissions with durations exceeding the time window). In some cases, the transmitter can intelligently switch between time-averaged and peak modes based on the transmission time determined according to radio conditions (and in some cases, the upload data buffer size). In some aspects, the transmission time is not explicitly calculated or determined, but rather the transmission mode is determined or otherwise selected based on one or more of the aforementioned (radio) conditions and the data transmitted using the concepts discussed herein.

[0168] In some respects, the UE can select the transmission mode for transmitting a signal at box 1006 based on various thresholds / conditions (or otherwise condition-based) associated with the transmission time determined at box 1004. For example, if the transmission time of Pmax determined at box 1004 is less than or equal to the burst transmission time, the UE can operate in time-averaged mode at box 1006 to transmit a signal, where the burst transmission time can refer to the maximum duration for which the UE can transmit at Pmax and has sufficient reserve power to continue transmitting at reduced transmission power within a time window associated with RF exposure limits. The reduced transmission power can be at a level sufficient to maintain a connection with the receiving entity. The burst transmission time can be the duration associated with Pmax (or a combined duration of multiple bursts) as shown in Figure 5C. Here, the transmission time at Pmax and the burst transmission time can be scaled based on an estimated (uplink) transmission duty cycle (as described herein) for comparison between the transmission time at Pmax and the burst transmission time and / or for comparison with a time window. For example, if the transmission duty cycle is low enough, the burst transmission time scaled by (1 / duty_cycle) can be greater than the time window. In this case, for such a low transmission duty cycle, the UE can continuously transmit at P max in time-averaged mode without exceeding the time-averaged exposure of P limit. Similarly, if P limit ≥ P max, the burst transmission time will be greater than the time window (e.g., 4, 100, or 360 seconds). In this case, UE operation in time-averaged or peak mode will allow the UE to continuously transmit at P max without exceeding the time-averaged transmit power of P limit.

[0169] The UE can determine the peak transmission for a given P max, P limit, and / or P reserve. If the transmit time at the P limit determined at box 1004 is greater than the time window associated with the RF exposure limit (e.g., 4, 100, or 360 seconds), the UE can operate in peak mode to transmit a signal at box 1006. If any transmit time determined at box 1004 is greater than the burst transmit time and less than the time window associated with the RF exposure limit, the UE can operate in time-averaged mode to transmit a signal at box 1006. In this case, the UE can transmit a signal at a power level between P max and P limit to provide a longer high-power duration at that power level, or transmit at P max and a lower P reserve to increase the high-power duration at the P max level. In other words, while transmitting a signal, the transmit power at box 1006 can be adjusted (e.g., increased or decreased) to ensure compliance with the RF exposure limit.

[0170] Regarding Operation 1000A, if the first transmit time determined at box 1004 is less than or equal to the burst transmit time associated with the transient power limit conforming to the RF exposure limit, then the transmit power at box 1006 may be limited by a transient power limit (e.g., P max), where the burst transmit time is less than the time window associated with the RF exposure limit. In some aspects, if the second transmit time determined at box 1004 is greater than or equal to the time window associated with the RF exposure limit, then the transmit power may be limited by an average power limit. If the transmit time associated with any of the plurality of transmit powers determined at box 1004 is less than or equal to the time window and greater than or equal to the burst transmit time, then the transmit power at box 1006 may be less than or equal to the transient power limit and greater than the average power during a first portion of the transmit time, and the transmit power at box 1006 may be less than the average power during a second portion of the transmit time.

[0171] As an example, regarding operation 1000A, if the transmit time determined at box 1004 is less than or equal to the burst transmit time, the transmit power at box 1006 can be set according to a time averaging mode (such as the time averaging mode described herein with respect to Figure 5C). If the transmit time determined at box 1004 is greater than or equal to the time window associated with the RF exposure limit, the transmit power at box 1006 can be set according to a peak mode (such as the peak mode described herein with respect to Figure 5B). If the transmit time associated with any of the plurality of transmit powers determined at box 1004 is less than or equal to the time window and greater than or equal to the burst transmit time, the transmit power at box 1006 can be set according to a time averaging mode such that the transmit power is less than or equal to the transient power limit and greater than the average power during the first part of the transmit time, and the transmit power of box 1006 may be less than the average power during the second part of the transmit time.

[0172] In some respects, the transmission time can be determined under the assumption that the current network conditions remain the same throughout the transmission to the receiving entity. Under mobility conditions (e.g., when the UE moves within a radio network and transmits to one or more receiving entities), the UE can use various models to estimate the transmission time. For example, the UE can use machine learning to predict / learn future network / radio conditions (e.g., a route from home to work), and the UE can use the predicted network / radio conditions at box 1004 to calculate the transmission time and / or select a transmission mode, for example, to decide whether to select a time-averaged mode, a peak mode, a combination thereof, or one or more other modes. Regarding operation 1000A, the UE can determine the transmission time under mobility conditions associated with the UE based at least in part on future predicted radio conditions. In some respects, future predicted radio conditions can be generated using machine learning, artificial intelligence, neural networks, regression analysis, etc. In some respects, a transmission mode is selected for the entire data transmission. In other respects, a transmission mode can be selected for each time window in which data will be transmitted. For example, when data is transmitted over two time windows, the UE can select a peak mode and transmit a portion of the data using the peak mode during the first time window of the two time windows, and can select a time-averaged mode and transmit the remaining portion of the data using the time-averaged mode during the second time window of the two time windows. Those skilled in the art will understand that these are merely examples, and the UE can make other choices or combinations of choices based on the concepts described herein.

[0173] In some aspects, future / current radio conditions, mobility conditions, buffer sizes, or other conditions described herein with respect to Operations 1000A and / or 1000B can be generated based on patterns such as those described above with respect to Figures 6-9B. These conditions may include parameters associated with past network conditions, user behavior, etc. In some aspects, data or buffer size, data rate, transmission time, etc., can be predicted, or determined values ​​related to one of these aspects can be modified or revised based on patterns. Therefore, determining the transmission time or any other operation described herein in box 1004 can be based on current values ​​or measurements (e.g., data currently in the buffer, measured SNR, etc.) and / or on predicted future values ​​(e.g., additional data that may be received in the buffer within a time window, changing network conditions, etc.), for example, based on machine learning, artificial intelligence, and (multiple) known or determined patterns.

[0174] In some respects, RF exposure limits may comply with limits set by regulatory / standards bodies (e.g., the U.S. Federal Communications Commission (FCC); Innovation, Science and Economic Development Canada (ISED); or the International Commission on Non-Ionizing Radiation Protection (ICNIRP) of the European Union). RF exposure limits may include SAR limits and / or PD limits for various frequency ranges. RF exposure limits may be averaged over a specified time window, such as 4 seconds for transmission frequencies between 24 GHz and 42 GHz, 100 seconds for transmission frequencies below 3 GHz, or 360 seconds for transmission frequencies below 6 GHz.

[0175] Figure 10B is a flowchart illustrating an example operation 1000B for wireless communication according to certain aspects of this disclosure. Operation 1000B can be performed, for example, by a UE (e.g., UE 120a in wireless communication network 100).

[0176] Operation 1000B may begin at box 1008, where the UE may select a transmission mode from multiple transmission modes (e.g., time-averaged mode and peak mode) based on data for transmission from the UE to a receiving entity (e.g., BS 110 and / or another UE 120) and one or more radio conditions associated with the transmission. The data and / or radio conditions may be current and / or measured, and / or future and / or predicted, for example, using machine learning, artificial intelligence, and / or parameters associated with past behavior and / or patterns. At box 1010, the UE may transmit a signal indicating the data to the receiving entity at a transmit power at least in part based on the selected transmission mode and RF exposure limits.

[0177] In block 1010 (or 1006), the UE may transmit at least a portion of the data at a power level higher than the average power of the RF exposure limit. In block 1010 (or 1006), the UE may transmit at a reserved power level (e.g., reserved power P reserve) lower than the average power level for at least a portion of a time window in which a portion of the data is transmitted. In some aspects, such as as further described herein, the reserve power level may be adjusted.

[0178] Multiple transmission modes may include at least a first mode and a second mode, wherein the first mode includes transmission at an average power level above and below the RF exposure limit, and the second mode includes transmission at a power level equal to or below the average power level. In other words, the first mode may correspond to the time-averaged mode described herein with respect to Figure 5C, and the second mode may correspond to the peak mode described herein with respect to Figure 5B.

[0179] For certain aspects, such as when performing Operation 600, Operation 1000A, and / or Operation 1000B, the operations described herein for determining transmit power may take into account or consider the transmission duty cycle. For example, the burst transmission time of P(t) at Pmax can be scaled by the transmission duty cycle. For short duty cycles, transmit power can be determined based on the duty cycle independently of Operation 600, Operation 1000A, and / or Operation 1000B, while for long duty cycles, transmit power 1000A can be determined based on Operation 600, Operation 1000B, and / or Operation 1000B. For example, if the duty cycle ensures that maximum exposure will not be reached regardless of the power used during transmission (e.g., because the amount of time with zero transmit power will result in an average power less than P limit), the UE can set the power to Pmax during transmission (e.g., a time-averaged mode can be selected) even when the burst transmission time is greater than the time window.

[0180] In some respects, as a supplement to or alternative to Operations 600, 1000A, and / or 1000B, the UE may adjust its reserve power (P reserve) based on one or more criteria. For example, after determining whether to execute a time-averaged or peak mode in Operations 1000A and / or 1000B, a certain transmit power behavior can be achieved by adjusting the reserve power, such as increasing or decreasing the reserve power to a specific level. The criteria used to adjust the reserve power may include machine learning or artificial intelligence used to predict certain future conditions (e.g., radio conditions, user behavior, mobility conditions, etc.) and / or estimate current conditions (e.g., the modes described herein). The criteria may include transmit times associated with transmission, such as those described herein with respect to Operations 1000A and / or 1000B. The criteria may include preferred transmit power behaviors or transmission modes, such as the peak mode depicted in Figure 5B. The criteria may include the conditions and / or modes described herein.

[0181] If the reserve power (P reserve) is set to the P limit, the transmission will behave similarly to peak mode, as shown in Figure 5B, for example, in a single-transmission scenario. If the reserve power is increased, the duration of P max decreases, and the duration of the reserve power increases, which can provide consistent transmit power over time. Alternatively, instead of setting the reserve power to the P limit, it can be set close to the P limit (e.g., 95% of the P limit), allowing 5% of the energy to be used for high-power bursts of P max, for example. In some cases, any unused reserve power from the radio can be allocated as part of the high-power burst margin or as additional margin for use by other radios in a multi-transmission scenario. In some respects, the reserve power can be defined and selected based on certain states, such as high (e.g., 95% of the P limit), normal (e.g., 80% of the P limit), and low (e.g., 10% of the P limit).

[0182] In some respects, reserve power can be adjusted in multi-transmission scenarios, for example, as described herein with respect to Figure 6. For instance, suppose a first radio requests a first reserve power and a second radio requests a second reserve power. If there is available reserve power after considering the first and second reserve powers, the total reserve power shared between the first and second radios can be increased. For example, the remaining reserve power (P delta) can be determined according to the following formula: (17) Where P reserve_high can be set to a specific power level less than or equal to P limit (e.g., 95% of P limit), and P reserve_radios is equal to the sum of the reserve power selected for each radio (e.g., the sum of the first reserve power of the first radio and the second reserve power of the second radio). Since the P limit values ​​may differ between radios in a multi-transmission scenario, the operation (17) can be performed by normalizing all quantities associated with the P limit for each radio. For example, P reserve_high will be replaced with the normalized reserve_high (e.g., = 0.95), P reserve_radios will be replaced with the normalized reserve_radios (e.g., the sum of the reserve power selected for each active radio, e.g., 0.90 = P reserve1 / P limit1 + P reserve2 / P limit2 + ... + P reserveN / P limitN), and P delta will be replaced with the normalized delta (e.g., 0.05). The remaining reserve power (P delta) can be distributed among the radios to increase the reserve power of the respective radios. For example, a first reserve power for a first radio can increase a portion of P delta, and a second reserve power can increase the remainder of P delta. The division of P delta can be determined using factors, such as 1 / (N radios). In some respects, such as based on the application or service used for the radio, the reserve power can be divided differently across radios.

[0183] Figures 11A-1100C are diagrams 1100A-1100C of the transmit power (P(t)) over time according to certain aspects of this disclosure, illustrating a time-averaged mode using dynamic reserve power. Referring to Figure 11A, the reserve power (P reserve) can be set to zero or none, allowing the longest duration of P max to be acquired within a time window (T). Referring to Figure 11B, the reserve power (P reserve) can be set to a power level less than a specific value of the reserve power (e.g., P reserve_reg). Referring to Figure 11C, the reserve power (P reserve) can be set to a power level greater than a specific value of the reserve power (e.g., P reserve_reg).

[0184] Various aspects of Operation 1000B can be applied to Operation 1000A, and vice versa. For example, the UE can perform the selection at block 1008 based on a transmission time(s) derived from radio conditions, data size, data rate, and / or a specific transmit power, as described herein with respect to block 1004. In block 1006 (or 1010), the UE can transmit a signal based on the selected transmission mode associated with block 1008. In some aspects, the transmit power used for Operation 1000A and / or Operation 1000B can be set in conjunction with another algorithm, such as the operation described herein with respect to Figures 7A-9B, or can be performed independently of other algorithms. In some such examples, due to the application of the algorithms described with respect to Figures 7A-9B, the transmit power can be set to a power lower than that determined in Operation 1000A or 1000B.

[0185] While aspects of this disclosure are described herein to facilitate understanding regarding the selection between a time-averaged mode and a peak mode based on estimated transmission times, these aspects can also be applied to selecting other transmission modes based on estimated transmission times and / or one or more (radio) conditions, such as a simple time-averaged mode or a combination of a time-averaged mode and a peak mode. In some examples, a mode and / or transmission power (e.g., in boxes 604, 1004, 1008) can be selected or determined to maximize the amount of time (or the amount of power transmitted at or above the P limit) by the transmitting device (e.g., UE) at or above the P limit. For example, if one or more bursts within a time window are sufficient to transmit data, the UE can determine to transmit (multiple) bursts above the P limit because there will inevitably be a period of time during which the transmission power will be zero (e.g., when the UE has finished transmitting all data), and transmitting above the P limit would increase or maximize the transmission power at or above the P limit. As another example, if a transmission burst causes the UE to later reduce its transmit power below the P limit (e.g., to the P reserve), the UE can determine to transmit all data at the P limit instead, so that it does not need to spend time transmitting below the P limit later.

[0186] While this document describes various methods for a UE to perform the examples depicted in Figure 1-11C to facilitate understanding in order to provide RF exposure compliance, aspects of this disclosure can also be applied to other wireless communication devices (wireless devices), such as base stations and / or CPEs, to perform the RF exposure compliance described herein. Furthermore, although examples of communication between a UE (or other wireless device) and a network entity are described, a UE or other wireless device can communicate with devices outside the network entity, such as another UE or another device in the user's home that is not a network entity.

[0187] Figure 12 illustrates a communication device 1200 (e.g., UE 120), which may include various elements (e.g., corresponding device plus functional elements) configured to perform operations using the techniques disclosed herein (e.g., operations shown in Figures 6, 10A, and / or 10B). The communication device 1200 includes a processing system 1202 coupled to a transceiver 1208 (e.g., a transmitter and / or receiver). The transceiver 1208 is configured to transmit and receive signals for the communication device 1200 via an antenna 1210, such as the various signals described herein. The processing system 1202 may be configured to perform processing functions for the communication device 1200, including processing signals received by and / or to be transmitted by the communication device 1200.

[0188] Processing system 1202 includes a processor 1204 coupled to computer-readable media / memory 1212 via bus 1206. In some aspects, computer-readable media / memory 1212 is configured to store instructions (e.g., computer-executable code) that, when executed by processor 1204, cause processor 1204 to perform the operations shown in Figures 6, 10A, and / or 10B, or other operations for performing the various techniques discussed herein to provide RF exposure compliance. In some aspects, computer-readable media / memory 1212 stores code 1214 for acquisition, code 1216 for determination or selection (or allocation or generation), code 1218 for transmission, code 1220 for selection, code 1222 for adjustment, code 1224 for allocation, and / or code 1226 for generation. In some aspects, processing system 1202 has a circuit system 1228 configured to implement the code stored in computer-readable media / memory 1212. In some respects, circuit system 1228 is coupled to processor 1204 and / or computer-readable media / memory 1212 via bus 1206. For example, circuit system 1228 includes circuit system 1230 for acquisition, circuit system 1232 for determination or selection (or allocation or generation), circuit system 1234 for transmission, circuit system 1236 for selection, circuit system 1238 for adjustment, circuit system 1240 for allocation, and / or circuit system 1242 for generation.

[0189] Various components of the communication device 1200 may provide parts for performing the methods described herein, including those relating to Figures 6-10B.

[0190] In some examples, the components for transmission or sending (or for outputting for transmission) may include transceiver 254 and / or antenna(s) 252 of UE 120 shown in FIG. 2 and / or transceiver 1208 and antenna 1210 of communication device 1200 in FIG. 12.

[0191] In some examples, the receiving component (or the acquiring component) may include the transceiver 254 and / or antenna(s) 252 of the UE 120 shown in FIG. 2 and / or the transceiver 1208 and antenna 1210 of the communication device 1200 in FIG. 12.

[0192] In some examples, the components for acquisition, determination, selection, adjustment, and / or generation may include various processing system elements, such as one or more processors 1204 in FIG. 12 or aspects of the UE 120 depicted in FIG. 2, including receive processor 258, transmit processor 264, TX MIMO processor 266, and / or controller / processor 280 (including RF exposure manager 281). Example

[0193] In addition to the aspects mentioned above, specific combinations of these aspects are also within the scope of this disclosure, some of which are detailed below:

[0194] Aspect 1. A method of wireless communication by a user equipment (UE), comprising: acquiring a pattern associated with one or more first transmissions; determining a transmit power for one or more second transmissions based at least in part on the pattern and radio frequency (RF) exposure limitations; and transmitting one or more second transmissions at the determined transmit power.

[0195] Aspect 2. The method according to aspect 1, wherein the mode includes at least one of the following: transmit power mode; antenna usage mode; user behavior mode; transmission type; priority mode; application mode; application type; wireless network mode; or sensor information.

[0196] Aspect 3. The method according to Aspect 2, wherein the transmit power mode includes one or more transmit powers on one or more time windows associated with RF exposure limits.

[0197] Aspect 4. According to the method of aspect 2 or 3, wherein the antenna usage mode includes an indication of time when the UE switches to a different transmission antenna.

[0198] Aspect 5. The method according to aspect 2, wherein the antenna usage mode includes usage modes for each of the plurality of radios.

[0199] Aspect 6. The method according to Aspect 2, wherein determining the transmit power comprises: determining a total available RF exposure margin based on the usage patterns for each of the plurality of radios; allocating an RF exposure margin to each of the radios based on the total available RF exposure margin; determining a transmit power cap for one of the radios based on the usage patterns for each of the other radios; and determining the transmit power for one or more second transmissions based at least in part on the transmit power cap and the RF exposure margin allocated to that one of the radios.

[0200] Aspect 7. The method according to Aspect 2, wherein determining the transmission power includes: determining an upper limit for the transmission power for the radio based on the usage pattern of the radio; and determining the transmission power for one or more second transmissions based at least in part on the upper limit for the transmission power.

[0201] Aspect 8. According to the method of aspect 7, wherein the upper limit of transmit power is less than the maximum transmit power supported by the UE and greater than the average power limit associated with RF exposure limit.

[0202] Aspect 9. The method according to aspect 6, wherein the usage pattern for each of the plurality of radios includes the average transmit power over past time intervals associated with the respective radio.

[0203] Aspect 10. According to the method of aspect 6, wherein determining the total available RF exposure margin includes: determining the difference between the maximum available utilization rate and the sum of usage patterns for radios.

[0204] Aspect 11. The method of aspect 10, wherein allocating RF exposure margin includes: allocating a certain proportion of the total available RF exposure margin to each of the radios as RF exposure margin for the respective radio.

[0205] Aspect 12. The method of aspect 11, wherein allocating a proportion of the total available RF exposure margin comprises allocating a proportion of the total available RF exposure margin to each of the radios based at least in part on a priority order associated with at least one of the radios.

[0206] Aspect 13. The method according to aspect 12, wherein at least one of the priority order or proportion of the total available RF exposure margin is associated with at least one of the frequency band, application, service, network conditions or exposure scenario associated with at least one of the radios.

[0207] Aspect 14. The method according to aspect 10, wherein determining the upper limit of transmit power includes: determining the difference between the maximum available utilization rate and the sum of the utilization patterns for each of the other radios.

[0208] Aspect 15. The method according to Aspect 6, wherein determining the transmit power comprises: determining the transmit power such that the transmit power is less than or equal to the minimum of the transmit power upper limit and the RF exposure margin allocated to one of the radios.

[0209] Aspect 16. The method according to aspect 6, wherein determining the transmission power includes: adjusting the upper limit of the transmission power in response to changes in the usage patterns of the radio.

[0210] Aspect 17. The method according to aspect 7, wherein determining the transmission power includes: adjusting the upper limit of the transmission power in response to changes in the usage patterns of the radio.

[0211] Aspect 18. The method according to aspect 16, wherein adjusting the upper limit of transmit power includes: adjusting the upper limit of transmit power in response to changes in the transmission scenario associated with radio.

[0212] Aspect 19. According to the method of aspect 16, wherein adjusting the upper limit of transmit power includes: adjusting the upper limit of transmit power at least in part based on the flow model.

[0213] Aspect 20. The method of aspect 6 or 7, wherein transmitting one or more second transmissions comprises: transmitting one or more second transmissions at a transmission power limit for a first portion of a time window associated with an RF exposure limit, and transmitting one or more second transmissions at a further transmission power less than the transmission power limit for a second portion of the time window.

[0214] Aspect 16. The method according to any one of Aspects 2 to 15, wherein the user behavior pattern includes one or more times associated with when the user uses the UE for wireless communication.

[0215] Aspect 17. The method according to any one of Aspects 2 to 16, wherein the application mode includes at least one of one or more transmission times or one or more transmission powers associated with one or more applications.

[0216] Aspect 18. The method according to any one of Aspects 2 to 17, wherein the application type indicates the type of application for generating the data for transmission.

[0217] Aspect 19. The method according to aspect 18, wherein determining the transmit power includes: determining the application type for one or more second transmissions; and determining the transmit power based on the application type taking precedence over other application types.

[0218] Aspect 20. The method according to any one of Aspects 2 to 19, wherein the wireless network mode includes at least one of the following: channel quality between the UE and the receiving entity; modulation coding scheme (MCS) associated with one or more first transmissions; coding rate associated with one or more first transmissions; period associated with one or more first transmissions; duty cycle associated with one or more first transmissions; or indication of UE mobility during one or more first transmissions.

[0219] Aspect 21. The method according to any one of Aspects 2 to 20, wherein the sensor information mode includes at least one of the following: indication of the proximity of the UE to a non-human object, indication of the UE being in free space, indication of the user's usage scenario, indication of the UE's usage status, or indication of the time when an antenna switch occurs at the UE.

[0220] Aspect 22. According to the method of aspect 21, wherein the user usage scenario indicates which part of the user's body the UE is close to.

[0221] Aspect 23. The method of any one of Aspects 1 to 22, wherein determining the transmit power includes at least in part using machine learning based on patterns to determine the transmit power.

[0222] Aspect 24. According to the method of aspect 23, wherein determining the transmit power includes: generating upcoming user behavior using machine learning; and determining the transmit power based on the upcoming user behavior and current network conditions.

[0223] Aspect 25. According to the method of aspect 23, wherein determining the transmit power includes: generating upcoming network conditions using machine learning; and determining the transmit power based on current user behavior and the upcoming network conditions.

[0224] Aspect 26. According to the method of aspect 23, wherein determining the transmit power includes: using machine learning to generate upcoming network conditions and upcoming user behavior; and determining the transmit power based on the upcoming network conditions and upcoming user behavior.

[0225] Aspect 27. The method of any one of Aspects 1 to 26, wherein determining the transmit power comprises: associating a mode with a transmit time associated with one or more second transmissions; comparing the transmit time with a time window associated with RF exposure limits; and determining the transmit power based on the comparison.

[0226] Aspect 28. The method according to any one of Aspects 1 to 27, wherein the RF exposure limitation includes specific absorption rate (SAR) limitation, power density (PD) limitation, or a combination thereof.

[0227] Aspect 29. The method of any one of Aspects 1 to 28, wherein at least one of the first transmissions occurs before the current time window used to determine the transmit power based on RF exposure limits.

[0228] Aspect 30. The method according to any one of Aspects 1 to 29, wherein determining includes determining the transmit power as a power above the average power level when the mode indicates that RF exposure margin may be available, and otherwise determining the transmit power as the average power level.

[0229] Aspect 31. According to the method of aspect 30, determining the transmit power as a power above the average power level also includes determining that network conditions indicate that higher transmission power would be beneficial or determining that high priority information is being transmitted.

[0230] Aspect 32. The method according to any one of Aspects 1 to 31, wherein determining includes comparing data stored in a transmission buffer with a usage predicted based on a pattern, or comparing the transmission power of data used to transmit data in a data buffer with a transmission power predicted based on a pattern.

[0231] Aspect 34. An apparatus for wireless communication, comprising: a memory; a processor coupled to the memory, the processor and the memory being configured to: acquire a mode associated with one or more first transmissions, and determine a transmit power for one or more second transmissions based at least in part on the mode and RF exposure limitations; and a transmitter configured to transmit one or more second transmissions at the determined transmit power.

[0232] Aspect 35. The apparatus according to aspect 34 is configured to perform any one of aspects 1 to 32.

[0233] Aspect 36. An apparatus for wireless communication, comprising: means for acquiring a pattern associated with one or more first transmissions; means for determining a transmit power for one or more second transmissions based at least in part on the pattern and RF exposure limitations; and means for transmitting one or more second transmissions at the determined transmit power.

[0234] Aspect 37. The apparatus according to aspect 36, the apparatus comprising a component for performing any one of aspects 1 to 32.

[0235] Aspect 38. A computer-readable medium having instructions stored thereon for: acquiring a mode associated with one or more first transmissions; determining a transmit power for one or more second transmissions based at least in part on the mode and RF exposure limits; and transmitting one or more second transmissions at the determined transmit power.

[0236] Aspect 39. The computer-readable medium according to aspect 38, wherein the computer-readable medium stores instructions for performing any one of aspects 1 to 32.

[0237] In addition to the aspects mentioned above, specific combinations of these aspects are also within the scope of this disclosure, some of which are detailed below:

[0238] Aspect 1: An apparatus for wireless communication, comprising: a memory; and a processor coupled to the memory, the processor and the memory being configured to: acquire a mode associated with one or more first transmissions, determine a transmit power for one or more second transmissions based at least in part on the mode and radio frequency (RF) exposure limitations, and transmit one or more second transmissions at the determined transmit power.

[0239] Aspect 2: The device according to aspect 1, wherein the mode includes at least one of the following: transmit power mode; antenna usage mode; user behavior mode; transmission type; priority mode; application mode; application type; wireless network mode; or sensor information.

[0240] Aspect 3: The apparatus according to aspect 1 or 2, wherein the processor and memory are further configured to: determine a first transmit power; determine a second transmit power based at least in part on the average transmit power over a time interval; select a third transmit power as the minimum of the first transmit power and the second transmit power; and determine a transmit power for one or more second transmissions such that the transmit power is less than or equal to the third transmit power.

[0241] Aspect 4: According to the apparatus of aspect 3, the second transmit power is based at least in part on the reciprocal of the normalized average transmit power over past time intervals.

[0242] Aspect 5: An apparatus according to any one of Aspects 1 to 4, wherein the processor and memory are further configured to: determine a first transmit power for each of a plurality of radios; determine a second transmit power for each of the plurality of radios, wherein the second transmit power is at least partially based on a normalized average transmit power for the respective radio over a time interval; select a third transmit power for each of the plurality of radios as the minimum of the first and second transmit powers for the respective radios; and determine a transmit power for one or more second transmissions such that the transmit power for each of the plurality of radios is less than or equal to the third transmit power for the respective radios.

[0243] Aspect 6: According to the apparatus of aspect 5, wherein the processor and memory are further configured to: determine a fourth transmit power based at least in part on the product of the maximum average power corresponding to the RF exposure limit of the respective radio and the reciprocal of the sum of the minimum of the normalized average transmit power for the plurality of radios, wherein the fourth transmit power is also based on the ratio between the normalized average transmit power for the respective radio and the total of the normalized average transmit power for the plurality of radios; determine a fifth transmit power, which is the maximum average power corresponding to the RF exposure limit divided by the number of the plurality of radios; and select a second transmit power based on the maximum of the fourth transmit power and the fifth transmit power.

[0244] Aspect 7: The apparatus according to aspect 5 or 6, wherein the processor and memory are further configured to: adjust the time interval of the normalized average transmit power based at least in part on the average power over a time window corresponding to the RF exposure limit; and select the maximum value of a first time interval and a second time interval that varies with the average transmit power over a past time window as the time interval, wherein the first time interval and the second time interval depend on the transmission frequency of one or more second transmissions.

[0245] Aspect 8: The apparatus according to any one of Aspects 5 to 7, wherein the processor and memory are further configured to adjust the time interval of the normalized average transmit power based at least in part on one or more current network conditions.

[0246] Aspect 9: An apparatus according to any one of Aspects 1 to 8, wherein the processor and memory are further configured to: determine a first transmit power; apply an upper limit to the first transmit power to determine a second transmit power; and determine a transmit power for one or more second transmissions such that the transmit power is less than or equal to the second transmit power.

[0247] Aspect 10: An apparatus according to any one of Aspects 1 to 9, wherein the processor and memory are further configured to: determine a first transmit power for one or more second transmissions based at least in part on time-averaged RF exposure in a past time window; determine a second transmit power based at least in part on normalized average transmit power for radio over a time interval; determine a third transmit power, the third transmit power being a maximum average power corresponding to an RF exposure limit; select a fourth transmit power as the minimum of the first and second transmit powers for radio; select a fifth transmit power as the minimum of the first and third transmit powers for radio; select a sixth transmit power from the first, fourth, and fifth transmit powers; and determine a transmit power for one or more second transmissions such that the transmit power is less than or equal to the sixth transmit power for radio.

[0248] Aspect 11: An apparatus according to any one of Aspects 1 to 10, wherein the processor and memory are further configured to: determine a first transmit power for each of a plurality of radios, wherein the first transmit power is at least partially based on a time-averaged RF exposure in a past time window; determine a second transmit power for each of the plurality of radios, wherein the second transmit power is at least partially based on a normalized average transmit power for the respective radio over a time interval; determine a third transmit power for each of the plurality of radios, wherein the third transmit power is a maximum average power corresponding to an RF exposure limit divided by the number of the plurality of radios; select a fourth transmit power for each of the plurality of radios as the minimum of the first and second transmit power for the respective radio; select a fifth transmit power for each of the plurality of radios as the minimum of the first and third transmit power for the respective radio; select a sixth transmit power for each of the plurality of radios among the first, fourth, and fifth transmit power for the respective radio; and determine a transmit power for one or more second transmissions such that the transmit power for each of the plurality of radios is less than or equal to the sixth transmit power for the respective radio.

[0249] Aspect 12: An apparatus according to any one of Aspects 2 to 11, wherein the processor and memory are further configured to: determine a total available RF exposure margin based on the usage pattern for each of the plurality of radios; allocate an RF exposure margin to each of the radios based on the total available RF exposure margin; determine a transmit power limit for one of the radios based on the usage pattern for each of the other radios; and determine a transmit power for one or more second transmissions based at least in part on the transmit power limit and the RF exposure margin allocated to one of the radios.

[0250] Aspect 13: An apparatus according to any one of Aspects 2 to 12, wherein the processor and memory are further configured to: determine a transmit power limit for the radio based on the usage pattern for the radio; and determine a transmit power for one or more second transmissions based at least in part on the transmit power limit, wherein the transmit power limit is less than the maximum transmit power supported by the apparatus and greater than the average power limit associated with RF exposure limits.

[0251] Aspect 14: The apparatus according to aspect 12 or 13, wherein the usage pattern for each of the plurality of radios includes the average transmit power over past time intervals associated with the respective radio.

[0252] Aspect 15: An apparatus according to any one of Aspects 12 to 14, wherein the processor and memory are further configured to determine the difference between the maximum available utilization rate and the sum of the radio usage patterns as the total available RF exposure margin.

[0253] Aspect 16: The apparatus according to aspect 15, wherein the processor and memory are further configured to: allocate a proportion of the total available RF exposure margin to each of the radios as an RF exposure margin for the respective radio; allocate the proportion of the total available RF exposure margin to each of the radios based at least in part on a priority order associated with at least one of the radios; and determine the difference between the maximum available utilization rate and the sum of the usage patterns for each of the other radios as a transmit power limit.

[0254] Aspect 17: The apparatus according to aspect 16, wherein at least one of the priority order or proportion of the total available RF exposure margin is associated with at least one of the frequency band, application, service, network conditions or exposure scenario associated with at least one of the radios.

[0255] Aspect 18: An apparatus according to any one of Aspects 12 to 17, wherein the processor and memory are further configured to: determine a transmit power such that the transmit power is less than or equal to the minimum of the transmit power upper limit and the RF exposure margin allocated to one of the radios.

[0256] Aspect 19: The apparatus according to any one of Aspects 12 to 18, wherein the processor and memory are further configured to: adjust the upper limit of the transmission power in response to changes in the mode of use of the radio.

[0257] Aspect 20: The apparatus according to any one of Aspects 2 to 19, wherein the processor and memory are further configured to: determine an application type for one or more second transmissions; and determine the transmission power based on the application type taking precedence over other application types.

[0258] Aspect 21: An apparatus according to any one of aspects 1 to 20, wherein the processor and memory are further configured to determine the transmit power using machine learning at least in part based on a pattern.

[0259] Aspect 22: The apparatus according to aspect 21, wherein the processor and memory are further configured to: generate at least one of upcoming user behavior or upcoming network conditions using machine learning; and determine the transmit power based on at least one of upcoming user behavior, current user behavior, upcoming network conditions, or current network conditions.

[0260] Aspect 23: An apparatus according to any one of Aspects 1 to 22, wherein the processor and memory are further configured to: associate a mode with a transmission time associated with one or more second transmissions; compare the transmission time with a time window associated with RF exposure limits; and determine the transmission power based on the comparison.

[0261] Aspect 24: A device according to any one of Aspects 2 to 23, wherein: the transmit power mode includes one or more transmit powers on one or more time windows associated with RF exposure limits; the antenna usage mode includes usage modes for each of a plurality of radios; the user behavior mode includes one or more times associated with when a user uses the device for wireless communication; the application mode includes at least one of one or more transmission times or one or more transmit powers associated with one or more applications; the application type indicates the type of application that generates data for transmission; the wireless network mode includes at least one of the following: channel quality between the device and a receiving entity; modulation coding scheme (MCS) associated with one or more first transmissions; coding rate associated with one or more first transmissions; period associated with one or more first transmissions; duty cycle associated with one or more first transmissions; or indication of device mobility during one or more first transmissions; sensor information includes at least one of the following: indication of proximity of the device to a non-human object; indication of the device being in free space; indication of user usage scenario; indication of device usage status; or indication of the time of antenna switching at the device; and the user usage scenario indicates which part of the user's body the device is close to.

[0262] Aspect 25: An apparatus according to any one of Aspects 1 to 24, wherein the RF exposure limitation includes specific absorption rate (SAR) limitation, power density (PD) limitation, or a combination thereof.

[0263] Aspect 26: A method of wireless communication by a wireless device, comprising: acquiring a pattern associated with one or more first transmissions; determining a transmit power for one or more second transmissions based at least in part on the pattern and radio frequency (RF) exposure limitations; and transmitting one or more second transmissions at the determined transmit power.

[0264] Aspect 27: According to the method of aspect 26, the mode includes at least one of the following: transmit power mode; antenna usage mode; user behavior mode; transmission type; priority mode; application mode; application type; wireless network mode; or sensor information.

[0265] Aspect 28: The method according to aspect 26 or 27, wherein determining the transmit power comprises: determining a first transmit power for each of a plurality of radios; determining a second transmit power for each of the plurality of radios, wherein the second transmit power is based at least in part on a normalized average transmit power for the respective radio over a time interval; selecting a third transmit power for each of the plurality of radios as the minimum of the first and second transmit powers for the respective radios; and determining a transmit power for one or more second transmissions such that the transmit power for each of the plurality of radios is less than or equal to the third transmit power for the respective radios.

[0266] Aspect 29: The method according to Aspect 27 or 28, wherein determining the transmit power comprises: determining a total available RF exposure margin based on the usage patterns for each of the plurality of radios; allocating an RF exposure margin to each of the radios based on the total available RF exposure margin; determining a transmit power cap for one of the radios based on the usage patterns for each of the other radios; and determining the transmit power for one or more second transmissions based at least in part on the transmit power cap and the RF exposure margin allocated to that one of the radios.

[0267] Aspect 30: The method of any one of Aspects 27 to 29, wherein determining the transmit power comprises: determining an upper limit of transmit power for the radio based on the usage pattern for the radio; and determining the transmit power for one or more second transmissions based at least in part on the upper limit of transmit power, wherein the upper limit of transmit power is less than the maximum transmit power supported by the wireless device and greater than the average power limit associated with RF exposure limits.

[0268] Aspect 31: An apparatus for wireless communication, comprising: a memory; and a processor coupled to the memory, the processor and the memory being configured to: acquire data for transmission to a receiving entity and radio conditions associated with the transmission, determine a transmission time associated with the data based at least in part on the radio conditions, and transmit a signal indicating the data to the receiving entity at a transmission power limited by radio frequency (RF) exposure based at least in part on the determined transmission time.

[0269] Aspect 32: The apparatus according to aspect 31, wherein: the transmission time is selected from a plurality of transmission times associated with a plurality of transmission powers; and the plurality of transmission powers include the transmission power of the transmitted signal.

[0270] Aspect 33: The apparatus according to aspect 32, wherein the plurality of transmission times include a first transmission time associated with a transient power limit supported by the apparatus and a second transmission time associated with an average power corresponding to an RF exposure limit.

[0271] Aspect 34: The apparatus according to aspect 33, wherein: if a first transmission time is less than or equal to a burst transmission time associated with a transient power limit that complies with an RF exposure limit, the transmission power is limited by a transient power limit, wherein the burst transmission time is less than a time window associated with an RF exposure limit; if a second transmission time is greater than or equal to a time window associated with an RF exposure limit, the transmission power is limited by an average power limit; and if a transmission time associated with any one of a plurality of transmission powers is less than or equal to a time window and greater than or equal to a burst transmission time, the transmission power is less than or equal to a transient power limit and greater than the average power for a first portion of the transmission time, and the transmission power is less than the average power for a second portion of the transmission time.

[0272] Aspect 35: The apparatus according to Aspect 33 or 34, wherein: if the transmission time is less than or equal to the burst transmission time associated with a transient power limit conforming to the RF exposure limit, the transmission power is set according to a time averaging mode, wherein the burst transmission time is less than a time window associated with the RF exposure limit; if the transmission time is greater than or equal to the time window associated with the RF exposure limit, the transmission power is set according to a peak mode; and if the transmission time associated with any one of the plurality of transmission powers is less than or equal to the time window and greater than or equal to the burst transmission time, the transmission power is set according to a time averaging mode such that the transmission power is less than or equal to the transient power limit and greater than the average power for a first portion of the transmission time, and the transmission power is less than the average power for a second portion of the transmission time.

[0273] Aspect 36: An apparatus according to any one of Aspects 31 to 35, wherein the radio conditions include at least one of the following: channel quality between the apparatus and the receiving entity; modulation coding scheme (MCS) associated with transmission; coding rate associated with transmission; or period associated with transmission to the receiving entity.

[0274] Aspect 37: An apparatus according to any one of aspects 31 to 36, wherein the processor and memory are further configured to: determine a data rate associated with transmitting data to a receiving entity based on radio conditions; and determine a transmission time based on the data rate and the size associated with the data.

[0275] Aspect 38: An apparatus according to any one of aspects 31 to 37, wherein the processor and memory are further configured to determine the transmission time based at least in part on future predicted radio conditions under mobility conditions associated with the apparatus.

[0276] Aspect 39: The apparatus according to aspect 38, wherein the processor and memory are further configured to generate future predictive radio conditions using machine learning.

[0277] Aspect 40: The apparatus according to any one of aspects 31 to 39, wherein the processor and memory are further configured to determine the transmission time based at least in part on the buffer size associated with the data.

[0278] Aspect 41: An apparatus according to any one of aspects 31 to 40, wherein the processor and memory are configured to: determine radio conditions based on a pattern associated with a first time window, wherein the first time window is separate from a second time window, and the second time window is associated with RF exposure limits.

[0279] Aspect 42: An apparatus for wireless communication, comprising: a memory; and a processor coupled to the memory, the processor and the memory further configured to: select a transmission mode from a plurality of transmission modes based on data for transmission from the apparatus to a receiving entity and one or more radio conditions associated with the transmission, and transmit a signal indicating data to the receiving entity at a transmit power at least in part based on the selected transmission mode and radio frequency (RF) exposure limits.

[0280] Aspect 43: The apparatus according to aspect 42, wherein the processor and memory are further configured to transmit at least a portion of the data at a power level higher than the average power level of the RF exposure limit.

[0281] Aspect 44: The apparatus according to aspect 43, wherein the processor and memory are configured to transmit at a power level higher than the average power level of the RF exposure limit during a time window associated with the RF exposure limit based on the duty cycle for transmission.

[0282] Aspect 45: The apparatus according to aspect 43 or 44, wherein the processor and memory are further configured to transmit at a standby power level below the average power level for at least a portion of a time window in which a portion of the data is transmitted.

[0283] Aspect 46: According to the device of aspect 45, the processor and memory are also configured to adjust the standby power level.

[0284] Aspect 47: An apparatus according to any one of Aspects 42 to 46, wherein: a plurality of transmission modes include at least a first mode and a second mode, the first mode including transmission at an average power level above an RF exposure limit and a power level below an average power level, and the second mode including transmission at a power level equal to or below an average power level; and one or more radio conditions including at least one of: channel quality between the apparatus and a receiving entity; modulation coding scheme (MCS) associated with the transmission; coding rate associated with the transmission; or period associated with the transmission to the receiving entity.

[0285] Aspect 48: A method of wireless communication by a wireless device, comprising: acquiring data for transmission to a receiving entity and radio conditions associated with the transmission; determining a transmission time associated with the data based at least in part on the radio conditions; and transmitting a signal indicating the data to the receiving entity at a transmission power limited by radio frequency (RF) exposure based at least in part on the determined transmission time.

[0286] Aspect 49: The method according to aspect 48, wherein: the transmission time is selected from a plurality of transmission times associated with a plurality of transmission powers; and the plurality of transmission powers include the transmission power of the transmitted signal, wherein the plurality of transmission times include a first transmission time associated with transient power limits supported by the wireless device and a second transmission time associated with an average power corresponding to RF exposure limits.

[0287] Aspect 50: According to the method of Aspect 49, wherein: if a first transmission time is less than or equal to a burst transmission time associated with a transient power limit that complies with an RF exposure limit, the transmission power is limited by a transient power limit, wherein the burst transmission time is less than a time window associated with an RF exposure limit; if a second transmission time is greater than or equal to a time window associated with an RF exposure limit, the transmission power is limited by an average power limit; and if the transmission time associated with any one of the plurality of transmission powers is less than or equal to a time window and greater than or equal to a burst transmission time, the transmission power is less than or equal to a transient power limit and greater than the average power for a first portion of the transmission time, and the transmission power is less than the average power for a second portion of the transmission time.

[0288] Aspect 51: According to the method of Aspect 49 or 50, wherein: if the transmission time is less than or equal to the burst transmission time associated with a transient power limit that complies with the RF exposure limit, the transmission power is set according to a time averaging mode, the burst transmission time being less than a time window associated with the RF exposure limit; if the transmission time is greater than or equal to the time window associated with the RF exposure limit, the transmission power is set according to a peak mode; and if the transmission time associated with any one of the multiple transmission powers is less than or equal to the time window and greater than or equal to the burst transmission time, the transmission power is set according to a time averaging mode such that the transmission power is less than or equal to the transient power limit and greater than the average power for a first portion of the transmission time, and the transmission power is less than the average power for a second portion of the transmission time.

[0289] Aspect 52: The method according to any one of Aspects 48 to 51, wherein the radio conditions include at least one of the following: channel quality between the radio device and the receiving entity; modulation coding scheme (MCS) associated with the transmission; coding rate associated with the transmission; or period associated with the transmission to the receiving entity.

[0290] Aspect 53: The method according to any one of Aspects 48 to 52, wherein determining the transmission time includes: determining the data rate associated with transmitting data to the receiving entity based on radio conditions; and determining the transmission time based on the data rate and the magnitude associated with the data.

[0291] Aspect 54: The method according to any one of Aspects 48 to 53, wherein determining the transmission time includes determining the transmission time based at least in part on future predicted radio conditions under mobility conditions associated with the device.

[0292] Aspect 55: The method according to any one of Aspects 48 to 54, wherein determining the transmission time includes determining the transmission time based at least in part on the buffer size associated with the data.

[0293] Aspect 56: A method of wireless communication by a wireless device, comprising: selecting a transmission mode from a plurality of transmission modes based on data for a transmission from the wireless device to a receiving entity and one or more radio conditions associated with the transmission; and transmitting a signal indicating data to the receiving entity at a transmit power at least in part based on the selected transmission mode and radio frequency (RF) exposure limits.

[0294] Aspect 57: According to the method of aspect 56, the transmission includes transmitting at least a portion of the data at a power level higher than the average power level of the RF exposure limit.

[0295] Aspect 58: According to the method of aspect 57, the transmission includes: transmitting at a standby power level below the average power level for at least a portion of a time window in which a portion of the transmitted data is transmitted.

[0296] Aspect 59: According to the method of aspect 58, the transmission includes adjusting the reserve power level.

[0297] Aspect 60: The method according to any one of Aspects 56 to 59, wherein: a plurality of transmission modes include at least a first mode and a second mode, the first mode including transmission at an average power level above and below the average power level, and the second mode including transmission at a power level equal to or below the average power level; and one or more radio conditions including at least one of: channel quality between the wireless device and the receiving entity; modulation coding scheme (MCS) associated with the transmission; coding rate associated with the transmission; or period associated with the transmission to the receiving entity.

[0298] Aspect 61: An apparatus comprising: a memory including executable instructions; one or more processors configured to execute the executable instructions and cause the apparatus to perform a method according to any one of aspects 26 to 30 or 48 to 60.

[0299] Aspect 62: An apparatus comprising components for performing the method according to any one of aspects 26 to 30 or 48 to 60.

[0300] Aspect 63: A computer-readable medium including executable instructions, which, when executed by one or more processors of the device, cause the device to perform a method according to any one of aspects 26 to 30 or 48 to 60.

[0301] Aspect 64: A computer program product embodied on a computer-readable storage medium, comprising code for performing a method according to any one of aspects 26 to 30 or 48 to 60.

[0302] The technologies described in this document can be used in various wireless communication technologies, such as NR (e.g., 5G NR), 3GPP Long Term Evolution (LTE), LTE-Advanced (LTE-A), Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC FDMA), Time Division Synchronous Code Division Multiple Access (TD-SCDMA), and other networks. The terms "network" and "system" are often used interchangeably. CDMA networks can implement radio technologies such as Universal Terrestrial Radio Access (UTRA) and cdma2000. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. cdma2000 covers the IS-2000, IS-95, and IS-856 standards. TDMA networks can implement radio technologies such as Global System for Mobile Communications (GSM). OFDMA networks can implement radio technologies such as NR (e.g., 5G RA), evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, and Flash-OFDMA. UTRA and E-UTRA are part of the Universal Mobile Telecommunications System (UMTS). LTE and LTE-A are versions of UMTS that use E UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents from an organization called the 3rd Generation Partnership Project (3GPP). cdma2000 and UMB are described in documents from an organization called the 3rd Generation Partnership Project 2 (3GPP2). NR is an emerging wireless communication technology under development.

[0303] In 3GPP, the term "community" can refer to the coverage area of ​​a Node B (NB) and / or the NB subsystem serving that coverage area, depending on the context in which the term is used. In NR systems, the term "community" is used interchangeably with BS, Next Generation Node B (gNB or gNodeB), Access Point (AP), Distributed Unit (DU), and Carrier or Transmitter Receiver Point (TRP). A BS can provide communication coverage for macro-communities, pico-communities, femto-communities, and / or other types of communities. A macro-community can cover a relatively large geographic area (e.g., a radius of several kilometers) and can allow unrestricted access for UEs with service subscriptions. A pico-community can cover a relatively small geographic area and can allow unrestricted access for UEs with service subscriptions. A femto-community can cover a relatively small geographic area (e.g., a home) and can allow restricted access for UEs associated with the femto-community (e.g., UEs in a Closed Subscriber Group (CSG), UEs of users in a home, etc.). A BS used for a macro-community can be called a macro BS. A BS used for a pico-community can be called a pico BS. A BS used for a femto-community can be called a femto-BS or a home BS.

[0304] A UE can also be referred to as a mobile station, terminal, access terminal, subscriber unit, station, customer premises equipment (CPE), cellular phone, smartphone, personal digital assistant (PDA), wireless modem, wireless communication device, handheld device, laptop, cordless phone, wireless local loop (WLL) station, tablet computer, camera, gaming device, netbook, smartbook, ultrabook, appliance, medical device or equipment, biometric sensor / device, wearable device (e.g., smartwatch, smart clothing, smart glasses, smart bracelet, smart jewelry (e.g., smart ring, smart bracelet, etc.)), entertainment device (e.g., music device, video device, satellite radio, etc.), vehicle component or sensor, smart instrument / sensor, industrial manufacturing equipment, Global Positioning System (GPS) device, or any other suitable device configured to communicate via wireless or wired media. Some UEs can be considered machine-type communication (MTC) devices or evolved MTC (eMTC) devices. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc., that can communicate with a BS, another device (e.g., a remote device), or some other entity. For example, wireless nodes can provide connectivity to networks (e.g., wide area networks such as the Internet or cellular networks) via wired or wireless communication links. Some UEs can be considered Internet of Things (IoT) devices; they can be narrowband IoT (NB-IoT) devices.

[0305] In some examples, access to the air interface can be scheduled. A scheduling entity (e.g., a BS) allocates resources for communication between some or all devices and equipment within its service area or community. The scheduling entity can be responsible for scheduling, allocating, reconfiguring, and releasing resources for one or more subordinate entities. That is, for scheduled communication, subordinate entities utilize resources allocated by the scheduling entity. A base station is not the only entity that can be used as a scheduling entity. In some examples, a UE can be used as a scheduling entity and can schedule resources for one or more subordinate entities (e.g., one or more other UEs), and other UEs can utilize the resources scheduled by that UE for radio communication. In some examples, a UE can be used as a scheduling entity in peer-to-peer (P2P) networks and / or mesh networks. In mesh network examples, in addition to communicating with scheduling entities, UEs can also communicate directly with each other.

[0306] The methods disclosed herein include one or more steps or actions for implementing these methods. Without departing from the scope of the claims, the steps and / or actions of the methods may be interchanged with each other. In other words, unless a specific order of steps or actions is specified, the order and / or use of a particular step and / or action may be modified without departing from the scope of the claims.

[0307] As used in this article, the phrase “at least one” in the list of items refers to any combination of these items, including a single member. For example, “at least one of a, b, or c” is intended to cover a, b, c, ab, ac, bc, and abc, as well as any combination with multiple identical elements (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbb, bbc, cc, and ccc, or any other order of a, b, and c).

[0308] As used herein, the term "determine" encompasses a variety of actions. For example, "determine" can include calculating, computing, processing, exporting, investigating, searching (e.g., looking in a table, database, or other data structure), confirming, etc. Furthermore, "determine" can include receiving (e.g., receiving information), accessing (e.g., accessing data in memory), etc. Additionally, "determine" can include parsing, selecting, picking, building, etc.

[0309] The preceding description is provided to enable those skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects. Therefore, the claims are not intended to be limited to the aspects shown herein, but rather to encompass the entire scope consistent with the language of the claims, wherein, unless otherwise specified, references to elements in the singular form are not intended to mean “one and only one”, but rather “one or more.” Unless otherwise specified, the term “some” means one or more. All structural and functional equivalents of elements of the various aspects described in this disclosure that are known to or subsequently known to those skilled in the art are expressly incorporated herein by reference and are intended to be covered by the claims. Furthermore, regardless of whether such disclosure is expressly referenced in the claims, nothing disclosed herein is intended for public use only. No element of the claims may be construed under 35:112(f) of the United States Code unless the element is construed using the phrase “means for” or, in the case of a method claims, using the phrase “step for”.

[0310] The various operations described above can be performed by any suitable component capable of performing the corresponding function. This component may include various hardware and / or software elements and / or parts, including but not limited to circuits, application-specific integrated circuits (ASICs), or processors. Typically, where operations as shown in the figures are present, these operations may include corresponding devices plus functional elements with similar numbering.

[0311] The various illustrative logic blocks, modules, and circuits described in connection with this disclosure may be implemented or executed using a general-purpose processor, digital signal processor (DSP), application-specific integrated circuit (ASIC), 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 may be a microprocessor, but alternatively, the processor may be any commercially available processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration.

[0312] If implemented in hardware, an example hardware setup may include a processing system in a wireless node. The processing system can be implemented using a bus architecture. Depending on the specific application and overall design constraints of the processing system, the bus may include any number of interconnecting buses and bridges. The bus can connect various circuitry, including processors, machine-readable media, and bus interfaces. The bus interface can be used to connect network interface cards (NICs) and the like to the processing system via the bus. The NIC can be used to implement signal processing functions at the physical (PHY) layer. In the case of a user equipment (UE) (see Figure 1), a user interface (e.g., keyboard, display, mouse, joystick, etc.) can also be connected to the bus. The bus can also connect various other circuitry well-known in the art and therefore will not be described further, such as timing sources, peripheral devices, voltage regulators, power management circuitry, etc. The processor can be implemented using one or more general-purpose and / or special-purpose processors. Examples include microprocessors, microcontrollers, DSP processors, and other circuitry systems capable of executing software. Those skilled in the art will recognize how best to implement the described functionality for the processing system, taking into account the specific application and the overall design constraints imposed on the system as a whole.

[0313] If implemented in software, these functions can be stored or transmitted as one or more instructions or code on a computer-readable medium. Software should be interpreted broadly as instructions, data, or any combination thereof, whether referring to software, firmware, middleware, microcode, hardware description languages, or others. Computer-readable media includes computer storage media and communication media, including any media that facilitates the transfer of computer programs from one place to another. The processor may be responsible for managing buses and general processing, including the execution of software modules stored on machine-readable storage media. Computer-readable storage media may be coupled to the processor, allowing the processor to read information from and write information to the storage media. Alternatively, the storage media may be integrated with the processor. For example, machine-readable media may include transmission lines, data-modulated carrier waves, and / or computer-readable storage media with instructions stored thereon, separate from the wireless node, all accessible to the processor via a bus interface. Alternatively or additionally, machine-readable media or any portion thereof may be integrated into the processor, for example, in cases where cache memory and / or general-purpose temporary registers may be present. Examples of machine-readable storage media may include, for example, RAM (Random Access Memory), flash memory, ROM (Read-Only Memory), PROM (Programmable Read-Only Memory), EPROM (Erasable Programmable Read-Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), registers, floppy disks, optical discs, hard disk drives, or any other suitable storage media, or any combination thereof. Machine-readable media may be embodied in computer program products.

[0314] Software modules may include single or multiple instructions and may be distributed across several different code segments, between different programs, and on multiple storage media. Computer-readable media may include multiple software modules. Software modules include instructions that, when executed by a device such as a processor, cause the processing system to perform various functions. Software modules may include transmission modules and reception modules. Each software module may reside in a single storage device or be distributed across multiple storage devices. For example, a software module may be loaded into RAM from a hard disk drive when a trigger event occurs. During the execution of a software module, the processor may load portions of the instructions into cache memory to improve access speed. One or more cache memory lines may then be loaded into a general-purpose temporary register for processor execution. When the functionality of a software module is mentioned below, it should be understood that this functionality is implemented by the processor when executing instructions from that software module.

[0315] Furthermore, any connection is properly referred to as computer-readable media. For example, if software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technology (e.g., infrared (IR), radio, and microwave), then coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technology (e.g., infrared, radio, and microwave) are all included in the definition of media. As used herein, magnetic discs and optical discs include compact discs (CDs), laser discs, optical discs, digital multifunction discs (DVDs), floppy discs, and Blu-ray® discs, wherein magnetic discs typically reproduce data magnetically, while optical discs reproduce data optically using lasers. Therefore, in some aspects, computer-readable media can include non-transitory computer-readable media (e.g., tangible media). Furthermore, in other aspects, computer-readable media can include transient computer-readable media (e.g., signals). Combinations of the above should also be included within the scope of computer-readable media.

[0316] Therefore, certain aspects may include computer program products for performing the operations presented herein. For example, such computer program products may include computer-readable media on which instructions are stored (and / or encoded) that are executable by one or more processors to perform the operations described herein, such as instructions for performing the operations described herein and shown in FIG. 6, FIG. 10A and / or FIG. 10B.

[0317] Furthermore, it should be understood that components and / or other suitable means for performing the methods and techniques described herein may be downloaded and / or otherwise acquired by the UE and / or base station where applicable. For example, such a device may be coupled to a server to facilitate the transfer of means for performing the methods described herein. Alternatively, the various methods described herein may be provided by storage devices (e.g., RAM, ROM, physical storage media such as optical discs (CDs) or floppy disks), such that the UE and / or base station can acquire the various methods by coupling or providing the storage device to the device. Furthermore, any other suitable techniques for providing the methods and techniques described herein to the device may be utilized.

[0318] It should be understood that the scope of the patent application is not limited to the precise configuration and components described above. Various modifications, alterations, and variations may be made to the arrangement, operation, and details of the above-described methods and apparatus without departing from the scope of the patent application.

[0319] 100: Wireless communication network 102a,102b,102c,102x,102y,102z: Community 110a,110b,110c,110x,110y,110z:BS 120,120a,120r,120x,120y:UE 130: Network Controller 132: Core Network 212: Source 220: Launch processor / processor 230: Transmit (TX) Multiple-Input Multiple-Output (MIMO) Processor / Processor 232a, 232t: Transceivers 234a, 234t: Antenna 236: MIMO detector 238: Receiver / Processor 239: Data Slot 240: Controller / Processor 242: Memory 244: Scheduler 252a, 252r: Antenna 254a, 254r: Transceivers 256: MIMO detector 258: Receiver / Processor 260: Data Slot 262: Source 264: Launch Processor / Processor 266:TX:MIMO processor / processor 280: Controller / Processor 281: RF Exposure Manager 282: Memory 300: RF transceiver circuit 302: Launch (TX) Path 304: Receive (RX) path 306: Antenna 308: Interface 310: Digital-to-Analog Converter (DAC) 312: Fundamental Frequency Filter (BBF) 314: Mixer 316: Driver Amplifier (DA) 318: Power Amplifier (PA) 320:TX Frequency Synthesizer 322: Amplifier 324: Low-noise amplifier (LNA) 326: Mixer 328: Baseband Filter (BBF) 330: Analog-to-Digital Converter (ADC) 332:RX Frequency Synthesizer 334: Amplifier 336: Controller 338: Memory 410: Normalized SAR distribution / distribution 420: Normalized PD distribution / distribution 430: Normalized distribution / distribution Graphs of transmit power (P(t)) for 500A, 500B, and 500C 600: Operation 602, 604, 606: Process 700A, 700B: Diagram 702: Sample Pattern / Pattern 704: First Transmission 706: Duration 708, 710: Second transmission 722: Mode 724: First Transmission 726: Duration 728: Second Transmission 730: Transmission Power 800A, 800B: Diagram 802: Mode 804: Time interval 806: Transmission 808: Transmission 822a, 822b, 822c: Mode 900A, 900B: Diagram 902: Mode 904: First Transmission 906: Second Transmission 908: Part One 910: Part Two 1000A, 1000B: Operation 1002, 1004, 1006: Process 1008, 1010: Process Graphs of transmit power (P(t)) for 1100A, 1100B, and 1100C 1200: Communication equipment 1202: Processing System 1204: Processor 1206: Busbar 1208: Transceiver 1210: Antenna 1212: Computer-readable media / memory 1214,1216,1218,1220,1222,1224,1226: Code 1228, 1230, 1232, 1234, 1236, 1238, 1240, 1242: Circuit System

Claims

1. An apparatus for wireless communication, the apparatus comprising: Memory; The device includes a processor coupled to the memory, the processor and the memory being configured to cause the device to: acquire a mode associated with one or more first transmissions; determine a first transmit power; determine a second transmit power based at least in part on an average transmit power over a time interval; select a third transmit power as the minimum of the first transmit power and the second transmit power; determine a transmit power for one or more second transmissions based at least in part on the mode and radio frequency (RF) exposure limits, such that the transmit power is less than or equal to the third transmit power; and transmit the one or more second transmissions at the determined transmit power.

2. The apparatus according to claim 1, wherein the mode includes at least one of the following: transmit power mode; antenna usage mode; user behavior mode; transmission type; priority mode; application mode; application type; wireless network mode; or sensor information.

3. The apparatus according to claim 1, wherein the second transmit power is based at least in part on the reciprocal of the normalized average transmit power over past time intervals.

4. The apparatus according to claim 1, wherein the processor and the memory are further configured to cause the apparatus to: determine a first transmit power for each of a plurality of radios; determine a second transmit power for each of the plurality of radios, wherein the second transmit power is based at least in part on a normalized value of the average transmit power for the respective radio over the time interval; select a third transmit power for each of the plurality of radios as the minimum of the first transmit power and the second transmit power for the respective radio; and determine the transmit power for the one or more second transmissions such that the transmit power for each of the plurality of radios is less than or equal to the third transmit power for the respective radio.

5. The apparatus of claim 4, wherein the processor and the memory are further configured to cause the apparatus to: determine a fourth transmit power based at least in part on the product of the maximum average power corresponding to the RF exposure limit for the respective radio and the reciprocal of the sum of the minimum of the normalized average transmit power and units for the plurality of radios, wherein the fourth transmit power is further based on a ratio between the normalized average transmit power for the respective radio and the sum of the normalized average transmit power for the plurality of radios; determine a fifth transmit power, the fifth transmit power being the maximum average power corresponding to the RF exposure limit divided by the number of the plurality of radios; and select a second transmit power based on the maximum of the fourth transmit power and the fifth transmit power.

6. The apparatus according to claim 4, wherein the processor and the memory are further configured to cause the apparatus to: adjust the time interval for the normalized average transmit power based at least in part on the average power over a time window corresponding to the RF exposure limit, wherein the adjustment includes: The time interval is selected as the maximum value of a first time interval and a second time interval that vary with the average transmit power over the past time window, wherein the first time interval and the second time interval depend on the transmission frequency of the one or more second transmissions.

7. The apparatus according to claim 4, wherein the processor and the memory are further configured to cause the apparatus to: adjust the time interval for the normalized average transmit power based at least in part on one or more current network conditions.

8. The apparatus according to claim 1, wherein the processor and the memory are further configured to cause the apparatus to: apply an upper limit to the first transmit power to determine the second transmit power; and determine the transmit power for the one or more second transmissions such that the transmit power is less than or equal to the second transmit power.

9. The apparatus of claim 1, wherein the processor and the memory are further configured to cause the apparatus to: determine a first transmit power for the one or more second transmissions based at least in part on time-averaged RF exposure over a past time window; determine a second transmit power based at least in part on a normalized value of the average transmit power for the radio over the time interval; determine a fourth transmit power, the fourth transmit power being a maximum average power corresponding to the RF exposure limit; select a third transmit power as the minimum of the first transmit power and the second transmit power for the radio; select a fifth transmit power as the minimum of the first transmit power and the fourth transmit power for the radio; select a sixth transmit power among the first transmit power, the third transmit power, and the fifth transmit power; and determine the transmit power for the one or more second transmissions such that the transmit power is less than or equal to the sixth transmit power for the radio.

10. The apparatus of claim 1, wherein the processor and the memory are further configured to cause the apparatus to: determine a first transmit power for each of a plurality of radios, wherein the first transmit power is at least partially based on a time-averaged RF exposure over a past time window; determine a second transmit power for each of the plurality of radios, wherein the second transmit power is at least partially based on a normalized value of the average transmit power for the respective radio over the time interval; determine a fourth transmit power for each of the plurality of radios, wherein the fourth transmit power is a maximum average power corresponding to the RF exposure limit divided by the number of the plurality of radios; select a third transmit power for each of the plurality of radios as the minimum of the first transmit power and the second transmit power for the respective radio; select a fifth transmit power for each of the plurality of radios as the minimum of the first transmit power and the fourth transmit power for the respective radio. A sixth transmit power is selected for each of the plurality of radios from the first, third, and fifth transmit power used for the respective radio; and the transmit power used for the one or more second transmissions is determined such that the transmit power used for each of the plurality of radios is less than or equal to the sixth transmit power used for the respective radio.

11. The apparatus of claim 2, wherein the processor and the memory are further configured to cause the apparatus to: determine the total available RF exposure margin based on the usage pattern for each of a plurality of radios; Based on the total available RF exposure margin, allocate an RF exposure margin to each of the radios; Based on the usage patterns for each of the other radios, determine the upper limit of the transmit power for one of the radios; The transmit power for the one or more second transmissions is determined based at least in part on the transmit power limit and the RF exposure margin allocated to one of the radios.

12. The apparatus of claim 2, wherein the processor and the memory are further configured to cause the apparatus to: determine a transmit power limit for the radio based on the usage pattern for the radio; and determine a transmit power for the one or more second transmissions based at least in part on the transmit power limit, wherein the transmit power limit is less than a maximum transmit power supported by the apparatus and greater than an average power limit associated with the RF exposure limit.

13. The apparatus of claim 11, wherein the usage pattern for each of the plurality of radios includes the average transmit power over past time intervals associated with the respective radio.

14. The apparatus of claim 11, wherein the processor and the memory are further configured to cause the apparatus to: determine the difference between the maximum available utilization rate and the sum of the usage patterns for the radio as the total available RF exposure margin.

15. The apparatus of claim 14, wherein the processor and the memory are further configured to cause the apparatus to: allocate a proportion of the total available RF exposure margin to each of the radios as the RF exposure margin for the respective radio; allocate the proportion of the total available RF exposure margin to each of the radios at least in part based on a priority order associated with at least one of the radios; and determine the transmit power cap as the difference between the maximum available utilization rate and the sum of the usage patterns for each of the other radios.

16. The apparatus of claim 15, wherein at least one of the priority order of the total available RF exposure margin or the proportion is associated with at least one of the frequency band, application, service, network conditions or exposure scenario associated with at least one of the radios.

17. The apparatus of claim 11, wherein the processor and the memory are further configured to cause the apparatus to: determine the transmit power such that the transmit power is less than or equal to the minimum of the transmit power upper limit and the RF exposure margin allocated to the one of the radios.

18. The apparatus of claim 11, wherein the processor and the memory are further configured to cause the apparatus to adjust the transmit power limit in response to changes in the usage mode of the radio.

19. The apparatus of claim 2, wherein the processor and the memory are further configured to cause the apparatus to: determine an application type for the one or more second transmissions; and determine the transmit power based on the application type being preferred over other application types.

20. The apparatus of claim 1, wherein the processor and the memory are further configured to cause the apparatus to: determine the transmit power using machine learning, at least in part based on the mode.

21. The apparatus of claim 20, wherein the processor and the memory are further configured to cause the apparatus to: generate at least one of an upcoming user behavior or an upcoming network condition using the machine learning; and determine the transmit power based on at least one of the upcoming user behavior, the current user behavior, the upcoming network condition, or the current network condition.

22. The apparatus of claim 1, wherein the processor and the memory are further configured to cause the apparatus to: associate the mode with a transmission time associated with the one or more second transmissions; compare the transmission time with a time window associated with the RF exposure limit; and determine the transmission power based on the comparison.

23. The apparatus according to claim 2, wherein: The transmit power mode includes one or more transmit powers over one or more time windows associated with the RF exposure limit; the antenna usage mode includes usage modes for each of the plurality of radios; the user behavior mode includes one or more times associated with when a user uses the device for wireless communication; the application mode includes at least one of one or more transmit times or one or more transmit powers associated with one or more applications; the application type indicates the type of application that generates the data for transmission; the wireless network mode includes at least one of the following: channel quality between the device and the receiving entity; modulation and coding scheme (MCS) associated with the one or more first transmissions; coding rate associated with the one or more first transmissions; period associated with the one or more first transmissions; duty cycle associated with the one or more first transmissions; or indication of mobility of the device during the one or more first transmissions. The sensor information includes at least one of the following: an indication of the proximity of the device to a non-human object, an indication of the device being in free space, an indication of the user's usage scenario, an indication of the usage status of the device, or an indication of when an antenna switch occurs at the device; and the user's usage scenario indicates which part of the user's body the device is close to.

24. The apparatus of claim 1, wherein the RF exposure limitation includes specific absorption rate (SAR) limitation, power density (PD) limitation, or a combination thereof.

25. A method for wireless communication by a wireless device, the method comprising: Obtain the mode associated with one or more first transmissions; Determine the first transmit power; A second transmit power is determined based at least in part on the average transmit power over a time interval; a third transmit power is selected as the minimum of the first transmit power and the second transmit power; a transmit power for one or more second transmissions is determined based at least in part on the mode and radio frequency (RF) exposure limits, such that the transmit power is less than or equal to the third transmit power; and the one or more second transmissions are transmitted at the determined transmit power.

26. The method according to claim 25, wherein the mode includes at least one of the following: transmit power mode; antenna usage mode; user behavior mode; transmission type; priority mode; application mode; application type; wireless network mode; or sensor information.

27. The method according to claim 25, wherein determining the transmit power includes: Determine the first transmit power for each of the multiple radios; Determine a second transmit power for each of the plurality of radios, wherein the second transmit power is at least partially based on a normalized value of the average transmit power for the respective radio over the time interval; select a third transmit power for each of the plurality of radios as the minimum of the first transmit power and the second transmit power for the respective radio; and determine the transmit power for the one or more second transmissions such that the transmit power for each of the plurality of radios is less than or equal to the third transmit power for the respective radio.

28. The method according to claim 26, wherein determining the transmit power includes: Determine the overall available RF exposure margin based on the usage patterns of each of the multiple radios; Based on the total available RF exposure margin, allocate an RF exposure margin to each of the radios; Based on the usage patterns for each of the other radios, determine the upper limit of the transmit power for one of the radios; The transmit power for the one or more second transmissions is determined based at least in part on the transmit power limit and the RF exposure margin allocated to one of the radios.

29. The method according to claim 26, wherein determining the transmit power includes: Determine the upper limit of the transmission power for radio based on the usage pattern of the radio. And at least in part based on the transmit power limit, the transmit power for the one or more second transmissions is determined, wherein the transmit power limit is less than the maximum transmit power supported by the wireless device and greater than the average power limit associated with the RF exposure limit.

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