Patent Description:
In a fifth-generation (<NUM>) New Radio (NR) access network, communication between the network and user equipment (UE) may utilize frequency-division duplex (FDD) or time-division duplex (TDD). In TDD, transmissions in different traffic directions on a given channel are separated from one another using time-division multiplexing. That is, at some times the channel is dedicated for transmissions in one direction (e.g., from device A to device B), while at other times the channel is dedicated for transmissions in the other direction (e.g., from device B to device A). In FDD, the transmitter and receiver at each endpoint can operate at different carrier frequencies or bands (i.e., frequency division multiplexing) for wireless communication.

FDD can be used for full-duplex communication or half-duplex communication, whereas TDD can be used for half-duplex communication. Full-duplex (FD) means both endpoints (e.g., transmitter and receiver) can communicate with one another in both transmit and receive directions simultaneously. Half-duplex (HD) means only one endpoint can send information to the other at a time. An NR network may support devices with various capabilities, cost, and performance requirements, for example, peak throughput, latency, reliability, power efficiency, etc..

<CIT> discloses dynamically changing between a full-duplex frequency division duplex operation and a half-duplex frequency division duplex operation in order to take advantage of operational aspects of both modes. In one example, the switch from one mode of operation to another mode of operation is in response to the detection of a trigger event, which may be a pre-defined event that is indicative of an opportunity to optimize or simply modify the current transceiver operation. The switch may be triggered within the radio resource control.

<CIT> discloses the use of a controller to monitor downlink signal quality of a user equipment and to compare this to a threshold, and based on this comparison to switch between a full-duplex frequency division duplex operation and a half-duplex frequency division duplex operation. The result of the switch is to increase user equipment receiver sensitivity.

<CIT> also discloses deciding to switch from full-duplex frequency division duplex operation to half-duplex frequency division duplex operation in response to detecting a trigger condition where multiple radio stacks are activated in the apparatus simultaneously.

The following presents a summary of one or more aspects of the present disclosure, in order to provide a basic understanding of such aspects. Its sole purpose is to present some concepts of one or more aspects of the disclosure in a form as a prelude to the more detailed description that is presented later.

The scope of the present invention is defined by the scope of the appended claims. Any embodiments that do not fall under the scope of the claims are examples which are useful for understanding the invention, but do not form a part of the invention.

Aspects of the present disclosure provide wireless devices and methods that can flexibly and dynamically switch between different frequency-division duplex (FDD) modes including a half-duplex (HD) FDD mode and a full-duplex (FD) FDD mode in wireless communication. A wireless device can intelligently switch between a HD FDD mode and a FD FDD mode to meet different power consumption and performance need in various scenarios. In one example, the wireless device can use the HD FDD mode to achieve power saving in a radio resource control (RRC) connected state. In another example, the wireless device can intelligently switch to the FD FDD mode for mission critical traffic, performance, and/or coverage enhancement.

Other aspects, features, and embodiments will become apparent to those of ordinary skill in the art, upon reviewing the following description of specific, exemplary embodiments in conjunction with the accompanying figures. While features may be discussed relative to certain embodiments and figures below, all embodiments can include one or more of the advantageous features discussed herein. In other words, while one or more embodiments may be discussed as having certain advantageous features, one or more of such features may also be used in accordance with the various embodiments discussed herein. The scope of the present invention is defined by the scope of the appended claims.

While aspects and embodiments are described in this application by illustration to some examples, those skilled in the art will understand that additional implementations and use cases may come about in many different arrangements and scenarios. Innovations described herein may be implemented across many differing platform types, devices, systems, shapes, sizes, and packaging arrangements. For example, embodiments and/or uses may come about via integrated chip embodiments and other non-module-component based devices (e.g., end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail/purchasing devices, medical devices, AI-enabled devices, etc.). While some examples may or may not be specifically directed to use cases or applications, a wide assortment of applicability of described innovations may occur. Implementations may range a spectrum from chip-level or modular components to nonmodular, non-chip-level implementations and further to aggregate, distributed, or OEM devices or systems incorporating one or more aspects of the described innovations. In some practical settings, devices incorporating described aspects and features may also necessarily include additional components and features for implementation and practice of claimed and described embodiments. For example, transmission and reception of wireless signals necessarily includes a number of components for analog and digital purposes (e.g., hardware components including antenna, RF-chains, power amplifiers, modulators, buffer, processor(s), interleaver, adders/summers, etc.). It is intended that innovations described herein may be practiced in a wide variety of devices, chip-level components, systems, distributed arrangements, end-user devices, etc. of varying sizes, shapes and constitution.

Aspects of the present disclosure provide methods and apparatus for flexibly switching between different frequency-division duplex (FDD) modes in wireless communication. Examples of FDD modes include half-duplex (HD) FDD and full-duplex (FD) FDD. A FDD mode can use different carrier frequencies or bands for wireless communication in different directions. For example, a first wireless device can use a first carrier frequency or band to transmit communication signals to a second wireless device and use a second carrier frequency or band to receive communication signals from the second wireless device. In some aspects, a wireless device can flexibly switch between a FD FDD mode and a HD FDD mode in consideration of power consumption, desired performance, and other consideration.

In different technologies, standards, or contexts, a base station may variously be referred to by those skilled in the art as a base transceiver station (BTS), a radio base station, a radio transceiver, a transceiver function, a basic service set (BSS), an extended service set (ESS), an access point (AP), a Node B (NB), an eNode B (eNB), a gNode B (gNB), a transmission and reception point (TRP), or some other suitable terminology. In some examples, a base station may include two or more TRPs that may be collocated or non-collocated. Each TRP may communicate on the same or different carrier frequency within the same or different frequency band.

The radio access network <NUM> is further illustrated supporting wireless communication for multiple mobile apparatuses. A mobile apparatus may be referred to as user equipment (UE) in 3GPP standards, but may also be referred to by those skilled in the art as a mobile station (MS), a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal (AT), a mobile terminal, a wireless terminal, a remote terminal, a handset, a terminal, a user agent, a mobile client, a client, or some other suitable terminology. A UE may be an apparatus (e.g., a mobile apparatus) that provides a user with access to network services.

Within the present document, a "mobile" apparatus need not necessarily have a capability to move, and may be stationary. The term mobile apparatus or mobile device broadly refers to a diverse array of devices and technologies. UEs may include a number of hardware structural components sized, shaped, and arranged to help in communication; such components can include antennas, antenna arrays, RF chains, amplifiers, one or more processors, etc. electrically coupled to each other. For example, some non-limiting examples of a mobile apparatus include a mobile, a cellular (cell) phone, a smart phone, a session initiation protocol (SIP) phone, a laptop, a personal computer (PC), a notebook, a netbook, a smartbook, a tablet, a personal digital assistant (PDA), and a broad array of embedded systems, e.g., corresponding to an "Internet of things" (IoT). A mobile apparatus may additionally be an automotive or other transportation vehicle, a remote sensor or actuator, a robot or robotics device, a satellite radio, a global positioning system (GPS) device, an object tracking device, a drone, a multi-copter, a quad-copter, a remote control device, a consumer and/or wearable device, such as eyewear, a wearable camera, a virtual reality device, a smart watch, a health or fitness tracker, a digital audio player (e.g., MP3 player), a camera, a game console, etc. A mobile apparatus may additionally be a digital home or smart home device such as a home audio, video, and/or multimedia device, an appliance, a vending machine, intelligent lighting, a home security system, a smart meter, etc. A mobile apparatus may additionally be a smart energy device, a security device, a solar panel or solar array, a municipal infrastructure device controlling electric power (e.g., a smart grid), lighting, water, etc.; an industrial automation and enterprise device; a logistics controller; agricultural equipment, etc. Still further, a mobile apparatus may provide for connected medicine or telemedicine support, e.g., health care at a distance. Telehealth devices may include telehealth monitoring devices and telehealth administration devices, whose communication may be given preferential treatment or prioritized access over other types of information, e.g., in terms of prioritized access for transport of critical service data, and/or relevant quality of service (QoS) for transport of critical service data.

In addition, the uplink and/or downlink control information and/or traffic information may be transmitted on a waveform that may be time-divided into frames, subframes, slots, and/or symbols. As used herein, a symbol may refer to a unit of time that, in an orthogonal frequency division multiplexed (OFDM) waveform, carries one resource element (RE) per sub-carrier. A slot may carry <NUM> or <NUM> OFDM symbols. A subframe may refer to a duration of <NUM>. Multiple subframes or slots may be grouped together to form a single frame or radio frame. Within the present disclosure, a frame may refer to a predetermined duration (e.g., <NUM>) for wireless transmissions, with each frame consisting of, for example, <NUM> subframes of <NUM> each. Of course, these definitions are not required, and any suitable scheme for organizing waveforms may be utilized, and various time divisions of the waveform may have any suitable duration.

Referring now to <FIG>, by way of example and without limitation, a schematic illustration of a radio access network (RAN) <NUM> is provided. In some examples, the RAN <NUM> may be the same as the RAN <NUM> described above and illustrated in <FIG>. The geographic area covered by the RAN <NUM> may be divided into cellular regions (cells) that can be uniquely identified by a user equipment (UE) based on an identification broadcasted from one access point or base station. <FIG> illustrates macrocells <NUM>, <NUM>, and <NUM>, and a small cell <NUM>, each of which may include one or more sectors (not shown). A sector is a sub-area of a cell. All sectors within one cell are served by the same base station. A radio link within a sector can be identified by a single logical identification belonging to that sector. In a cell that is divided into sectors, the multiple sectors within a cell can be formed by groups of antennas with each antenna responsible for communication with UEs in a portion of the cell.

Within the RAN <NUM>, the cells may include UEs that may be in communication with one or more sectors of each cell. Further, each base station <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> may be configured to provide an access point to a core network <NUM> (see <FIG>) for all the UEs in the respective cells. For example, UEs <NUM> and <NUM> may be in communication with base station <NUM>; UEs <NUM> and <NUM> may be in communication with base station <NUM>; UEs <NUM> and <NUM> may be in communication with base station <NUM> by way of RRH <NUM>; UE <NUM> may be in communication with base station <NUM>; and UE <NUM> may be in communication with mobile base station <NUM>. In some examples, the UEs <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and/or <NUM> may be the same as the UE/scheduled entity <NUM> described above and illustrated in <FIG>.

In a further aspect of the RAN <NUM>, sidelink signals may be used between UEs without necessarily relying on scheduling or control information from a base station. For example, two or more UEs (e.g., UEs <NUM>, <NUM>, and <NUM>) may communicate with each other using peer to peer (P2P) or sidelink signals <NUM> without relaying that communication through a base station. In some examples, the UEs <NUM>, <NUM>, and <NUM> may each function as a scheduling entity or transmitting sidelink device and/or a scheduled entity or a receiving sidelink device to schedule resources and communicate sidelink signals <NUM> therebetween without relying on scheduling or control information from a base station. In other examples, two or more UEs (e.g., UEs <NUM> and <NUM>) within the coverage area of a base station (e.g., base station <NUM>) may also communicate sidelink signals <NUM> over a direct link (sidelink) without conveying that communication through the base station <NUM>. In this example, the base station <NUM> may allocate resources to the UEs <NUM> and <NUM> for the sidelink communication. In either case, such sidelink signaling <NUM> and <NUM> may be implemented in a P2P network, a device-to-device (D2D) network, vehicle-to-vehicle (V2V) network, a vehicle-to-everything (V2X), a mesh network, or other suitable direct link network.

In the radio access network <NUM>, the ability for a UE to communicate while moving, independent of its location, is referred to as mobility. The various physical channels between the UE and the radio access network are generally set up, maintained, and released under the control of an access and mobility management function (AMF, not illustrated, part of the core network <NUM> in <FIG>), which may include a security context management function (SCMF) and a security anchor function (SEAF) that perform authentication. The SCMF can manage, in whole or in part, the security context for both the control plane and the user plane functionality.

In various aspects of the disclosure, a radio access network <NUM> may utilize DL-based mobility or UL-based mobility to enable mobility and handovers (i.e., the transfer of a UE's connection from one radio channel to another). In a network configured for DL-based mobility, during a call with a scheduling entity, or at any other time, a UE may monitor various parameters of the signal from its serving cell as well as various parameters of neighboring cells. Depending on the quality of these parameters, the UE may maintain communication with one or more of the neighboring cells. During this time, if the UE moves from one cell to another, or if signal quality from a neighboring cell exceeds that from the serving cell for a given amount of time, the UE may undertake a handoff or handover from the serving cell to the neighboring (target) cell. For example, UE <NUM> (illustrated as a vehicle, although any suitable form of UE may be used) may move from the geographic area corresponding to its serving cell <NUM> to the geographic area corresponding to a neighbor cell <NUM>. When the signal strength or quality from the neighbor cell <NUM> exceeds that of its serving cell <NUM> for a given amount of time, the UE <NUM> may transmit a reporting message to its serving base station <NUM> indicating this condition. In response, the UE <NUM> may receive a handover command, and the UE may undergo a handover to the cell <NUM>.

In a network configured for UL-based mobility, UL reference signals from each UE may be utilized by the network to select a serving cell for each UE. In some examples, the base stations <NUM>, <NUM>, and <NUM>/<NUM> may broadcast unified synchronization signals (e.g., unified Primary Synchronization Signals (PSSs), unified Secondary Synchronization Signals (SSSs) and unified Physical Broadcast Channels (PBCH)). The UEs <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> may receive the unified synchronization signals, derive the carrier frequency and slot timing from the synchronization signals, and in response to deriving timing, transmit an uplink pilot or reference signal. The uplink pilot signal transmitted by a UE (e.g., UE <NUM>) may be concurrently received by two or more cells (e.g., base stations <NUM> and <NUM>/<NUM>) within the radio access network <NUM>. Each of the cells may measure a strength of the pilot signal, and the radio access network (e.g., one or more of the base stations <NUM> and <NUM>/<NUM> and/or a central node within the core network) may determine a serving cell for the UE <NUM>. As the UE <NUM> moves through the radio access network <NUM>, the network may continue to monitor the uplink pilot signal transmitted by the UE <NUM>. When the signal strength or quality of the pilot signal measured by a neighboring cell exceeds that of the signal strength or quality measured by the serving cell, the network <NUM> may handover the UE <NUM> from the serving cell to the neighboring cell, with or without informing the UE <NUM>.

In various implementations, the air interface in the radio access network <NUM> may utilize licensed spectrum, unlicensed spectrum, or shared spectrum. Licensed spectrum provides for exclusive use of a portion of the spectrum, generally by virtue of a mobile network operator purchasing a license from a government regulatory body. Unlicensed spectrum provides for shared use of a portion of the spectrum without need for a government-granted license. While compliance with some technical rules is generally still required to access unlicensed spectrum, generally, any operator or device may gain access. Shared spectrum may fall between licensed and unlicensed spectrum, wherein technical rules or limitations may be required to access the spectrum, but the spectrum may still be shared by multiple operators and/or multiple RATs. For example, the holder of a license for a portion of licensed spectrum may provide licensed shared access (LSA) to share that spectrum with other parties, e.g., with suitable licensee-determined conditions to gain access.

The air interface in the radio access network <NUM> may utilize one or more duplexing algorithms. Duplex refers to a point-to-point communication link where both endpoints can communicate with one another in both directions. Full-duplex means both endpoints can simultaneously communicate with one another. Half-duplex means only one endpoint can send information to the other at a time. Half-duplex emulation is frequently implemented for wireless links utilizing time division duplex (TDD). In TDD, transmissions in different directions on a given channel (e.g., within the same carrier bandwidth) are separated from one another using time division multiplexing. That is, at some times (e.g., a first slot/symbol) the channel is dedicated for transmissions in one direction, while at other times (e.g., a second slot/symbol) the channel is dedicated for transmissions in the other direction, where the direction may change very rapidly, e.g., several times per slot. In a wireless link, a full-duplex channel generally relies on physical isolation of a transmitter and receiver, and suitable interference cancellation technologies. Full-duplex emulation is frequently implemented for wireless links by utilizing frequency division duplex (FDD) or spatial division duplex (SDD). In SDD, transmissions in different directions on a given channel are separated from one another using spatial division multiplexing (SDM). In one example of FDD, transmissions in different directions may operate at different carrier frequencies (e.g., within paired spectrum). In another example of FDD, full-duplex communication may be implemented within unpaired spectrum (e.g., within a single carrier bandwidth), where transmissions in different directions occur within different sub-bands of the carrier bandwidth. This type of full-duplex communication may also be referred to herein as sub-band full-duplex (SBFD) or flexible duplex. FDD may also be utilized in HD modes of operation, where transmissions in different directions are separated in both time and frequency.

Further, the air interface in the radio access network <NUM> may utilize one or more multiplexing and multiple access algorithms to enable simultaneous communication of the various devices. For example, <NUM> NR specifications provide multiple access for UL transmissions from UEs <NUM> and <NUM> to base station <NUM>, and for multiplexing for DL transmissions from base station <NUM> to one or more UEs <NUM> and <NUM>, utilizing orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP). In addition, for UL transmissions, <NUM> NR specifications provide support for discrete Fourier transform-spread-OFDM (DFT-s-OFDM) with a CP (also referred to as single-carrier FDMA (SC-FDMA)). However, within the scope of the present disclosure, multiplexing and multiple access are not limited to the above schemes, and may be provided utilizing time division multiple access (TDMA), code division multiple access (CDMA), frequency division multiple access (FDMA), sparse code multiple access (SCMA), resource spread multiple access (RSMA), or other suitable multiple access schemes. Further, multiplexing DL transmissions from the base station <NUM> to UEs <NUM> and <NUM> may be provided utilizing time division multiplexing (TDM), code division multiplexing (CDM), frequency division multiplexing (FDM), orthogonal frequency division multiplexing (OFDM), sparse code multiplexing (SCM), or other suitable multiplexing schemes.

Various aspects of the present disclosure will be described with reference to an OFDM waveform, schematically illustrated in <FIG>. It should be understood by those of ordinary skill in the art that the various aspects of the present disclosure may be applied to an SC-FDMA waveform in substantially the same way as described herein below. That is, while some examples of the present disclosure may focus on an OFDM link for clarity, it should be understood that the same principles may be applied as well to SC-FDMA waveforms.

Referring now to <FIG>, an expanded view of an exemplary subframe <NUM> is illustrated, showing an OFDM resource grid. However, as those skilled in the art will readily appreciate, the PHY transmission structure for any particular application may vary from the example described here, depending on any number of factors. Here, time is in the horizontal direction with units of OFDM symbols; and frequency is in the vertical direction with units of subcarriers of the carrier.

The resource grid <NUM> may be used to schematically represent time-frequency resources for a given antenna port. That is, in a multiple-input-multiple-output (MIMO) implementation with multiple antenna ports available, a corresponding multiple number of resource grids <NUM> may be available for communication. The resource grid <NUM> is divided into multiple resource elements (REs) <NUM>. An RE, which is <NUM> subcarrier × <NUM> symbol, is the smallest discrete part of the time-frequency grid, and contains a single complex value representing data from a physical channel or signal. Depending on the modulation utilized in a particular implementation, each RE may represent one or more bits of information. In some examples, a block of REs may be referred to as a physical resource block (PRB) or more simply a resource block (RB) <NUM>, which contains any suitable number of consecutive subcarriers in the frequency domain. In one example, an RB may include <NUM> subcarriers, a number independent of the numerology used. In some examples, depending on the numerology, an RB may include any suitable number of consecutive OFDM symbols in the time domain. Within the present disclosure, it is assumed that a single RB such as the RB <NUM> entirely corresponds to a single direction of communication (either transmission or reception for a given device).

A set of continuous or discontinuous resource blocks may be referred to herein as a Resource Block Group (RBG), sub-band, or bandwidth part (BWP). A set of sub-bands or BWPs may span the entire bandwidth. Scheduling of scheduled entities (e.g., UEs) for downlink, uplink, or sidelink transmissions typically involves scheduling one or more resource elements <NUM> within one or more sub-bands or bandwidth parts (BWPs). Thus, a UE generally utilizes only a subset of the resource grid <NUM>. In some examples, an RB may be the smallest unit of resources that can be allocated to a UE. Thus, the more RBs scheduled for a UE, and the higher the modulation scheme chosen for the air interface, the higher the data rate for the UE. The RBs may be scheduled by a scheduling entity, such as a base station (e.g., gNB, eNB, etc.), or may be self-scheduled by a UE implementing D2D sidelink communication.

Each <NUM> subframe <NUM> may consist of one or multiple adjacent slots. In the example shown in <FIG>, one subframe <NUM> includes four slots <NUM>, as an illustrative example. In some examples, a slot may be defined according to a specified number of OFDM symbols with a given cyclic prefix (CP) length. For example, a slot may include <NUM> or <NUM> OFDM symbols with a nominal CP. Additional examples may include mini-slots, sometimes referred to as shortened transmission time intervals (TTIs), having a shorter duration (e.g., one to three OFDM symbols). These mini-slots or shortened transmission time intervals (TTIs) may in some cases be transmitted occupying resources scheduled for ongoing slot transmissions for the same or for different UEs. Any number of resource blocks may be utilized within a subframe or slot.

An expanded view of one of the slots <NUM> illustrates the slot <NUM> including a control region <NUM> and a data region <NUM>. In general, the control region <NUM> may carry control channels, and the data region <NUM> may carry data channels. Of course, a slot may contain all DL, all UL, or at least one DL portion and at least one UL portion. The structure illustrated in <FIG> is merely exemplary in nature, and different slot structures may be utilized, and may include one or more of each of the control region(s) and data region(s).

Although not illustrated in <FIG>, the various REs <NUM> within a RB <NUM> may be scheduled to carry one or more physical channels, including control channels, shared channels, data channels, etc. Other REs <NUM> within the RB <NUM> may also carry pilots or reference signals. These pilots or reference signals may provide for a receiving device to perform channel estimation of the corresponding channel, which may enable coherent demodulation/detection of the control and/or data channels within the RB <NUM>.

In some examples, the slot <NUM> may be utilized for broadcast, multicast, groupcast, or unicast communication. For example, a broadcast, multicast, or groupcast communication may refer to a point-to-multipoint transmission by one device (e.g., a base station, UE, or other similar device) to other devices. Here, a broadcast communication is delivered to all devices, whereas a multicast or groupcast communication is delivered to multiple intended recipient devices. A unicast communication may refer to a point-to-point transmission by a one device to a single other device.

In an example of cellular communication over a cellular carrier via a Uu interface, for a DL transmission, the scheduling entity (e.g., a base station) may allocate one or more REs <NUM> (e.g., within the control region <NUM>) to carry DL control information including one or more DL control channels, such as a physical downlink control channel (PDCCH), to one or more scheduled entities (e.g., UEs). The PDCCH carries downlink control information (DCI) including but not limited to power control commands (e.g., one or more open loop power control parameters and/or one or more closed loop power control parameters), scheduling information, a grant, and/or an assignment of REs for DL and UL transmissions. The PDCCH may further carry HARQ feedback transmissions such as an acknowledgment (ACK) or negative acknowledgment (NACK). HARQ is a technique well-known to those of ordinary skill in the art, wherein the integrity of packet transmissions may be checked at the receiving side for accuracy, e.g., utilizing any suitable integrity checking mechanism, such as a checksum or a cyclic redundancy check (CRC). If the integrity of the transmission is confirmed, an ACK may be transmitted, whereas if not confirmed, a NACK may be transmitted. In response to a NACK, the transmitting device may send a HARQ retransmission, which may implement chase combining, incremental redundancy, etc..

The base station may further allocate one or more REs <NUM> (e.g., in the control region <NUM> or the data region <NUM>) to carry other DL signals, such as a demodulation reference signal (DMRS); a phase-tracking reference signal (PT-RS); a channel state information (CSI) reference signal (CSI-RS); and a synchronization signal block (SSB). SSBs may be broadcast at regular intervals based on a periodicity (e.g., <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM>). An SSB includes a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a physical broadcast control channel (PBCH). A UE may utilize the PSS and SSS to achieve radio frame, subframe, slot, and symbol synchronization in the time domain, identify the center of the channel (system) bandwidth in the frequency domain, and identify the physical cell identity (PCI) of the cell.

The PBCH in the SSB may further include a master information block (MIB) that includes various system information, along with parameters for decoding a system information block (SIB). The SIB may be, for example, a SystemInformationType <NUM> (SIB1) that may include various additional system information. The MIB and SIB1 together provide the minimum system information (SI) for initial access. Examples of system information transmitted in the MIB may include, but are not limited to, a subcarrier spacing (e.g., default downlink numerology), system frame number, a configuration of a PDCCH control resource set (CORESET) (e.g., PDCCH CORESET0), a cell barred indicator, a cell reselection indicator, a raster offset, and a search space for SIB1. Examples of remaining minimum system information (RMSI) transmitted in the SIB1 may include, but are not limited to, a random access search space, a paging search space, downlink configuration information, and uplink configuration information.

In an UL transmission, the scheduled entity (e.g., UE) may utilize one or more REs <NUM> to carry UL control information (UCI) including one or more UL control channels, such as a physical uplink control channel (PUCCH), to the scheduling entity. UCI may include a variety of packet types and categories, including pilots, reference signals, and information configured to enable or assist in decoding uplink data transmissions. Examples of uplink reference signals may include a sounding reference signal (SRS) and an uplink DMRS. In some examples, the UCI may include a scheduling request (SR), i.e., request for the scheduling entity to schedule uplink transmissions. Here, in response to the SR transmitted on the UCI, the scheduling entity may transmit downlink control information (DCI) that may schedule resources for uplink packet transmissions. UCI may also include HARQ feedback, channel state feedback (CSF), such as a CSI report, or any other suitable UCI.

In addition to control information, one or more REs <NUM> (e.g., within the data region <NUM>) may be allocated for data traffic. Such data traffic may be carried on one or more traffic channels, such as, for a DL transmission, a physical downlink shared channel (PDSCH); or for an UL transmission, a physical uplink shared channel (PUSCH). In some examples, one or more REs <NUM> within the data region <NUM> may be configured to carry other signals, such as one or more SIBs and DMRSs.

In an example of sidelink communication over a sidelink carrier via a proximity service (ProSe) PC5 interface, the control region <NUM> of the slot <NUM> may include a physical sidelink control channel (PSCCH) including sidelink control information (SCI) transmitted by an initiating (transmitting) sidelink device (e.g., Tx V2X device or other Tx UE) towards a set of one or more other receiving sidelink devices (e.g., Rx V2X device or other Rx UE). The data region <NUM> of the slot <NUM> may include a physical sidelink shared channel (PSSCH) including sidelink data traffic transmitted by the initiating (transmitting) sidelink device within resources reserved over the sidelink carrier by the transmitting sidelink device via the SCI. Other information may further be transmitted over various REs <NUM> within slot <NUM>. For example, HARQ feedback information may be transmitted in a physical sidelink feedback channel (PSFCH) within the slot <NUM> from the receiving sidelink device to the transmitting sidelink device. In addition, one or more reference signals, such as a sidelink SSB, a sidelink CSI-RS, a sidelink SRS, and/or a sidelink positioning reference signal (PRS) may be transmitted within the slot <NUM>.

The channels or carriers illustrated in <FIG> are not necessarily all of the channels or carriers that may be utilized between devices, and those of ordinary skill in the art will recognize that other channels or carriers may be utilized in addition to those illustrated, such as other traffic, control, and feedback channels.

In OFDM, to maintain orthogonality of the subcarriers or tones, the subcarrier spacing may be equal to the inverse of the symbol period. A numerology of an OFDM waveform refers to its particular subcarrier spacing and cyclic prefix (CP) overhead. A scalable numerology refers to the capability of the network to select different subcarrier spacings, and accordingly, with each spacing, to select the corresponding symbol duration, including the CP length. With a scalable numerology, a nominal subcarrier spacing (SCS) may be scaled upward or downward by integer multiples. In this manner, regardless of CP overhead and the selected SCS, symbol boundaries may be aligned at certain common multiples of symbols (e.g., aligned at the boundaries of each <NUM> subframe). The range of SCS may include any suitable SCS. For example, a scalable numerology may support a SCS ranging from <NUM> to <NUM>.

To illustrate this concept of a scalable numerology, <FIG> shows a first RB <NUM> having a nominal numerology, and a second RB <NUM> having a scaled numerology relative to the nominal numerology. As one example, the first RB <NUM> may have a nominal subcarrier spacing (SCSn) of <NUM>, and a nominal symbol durationn of <NUM>. Here, in the second RB <NUM>, the scaled numerology includes a scaled SCS of double the nominal SCS, or <NUM> × SCSn = <NUM>. Because this provides twice the bandwidth per symbol, it results in a shortened symbol duration to carry the same information. Thus, in the second RB <NUM>, the scaled numerology includes a scaled symbol duration of half the nominal symbol duration, or (symbol durationn)÷<NUM> = <NUM>.

<FIG> is a diagram illustrating exemplary half-duplex TDD and sub-band full-duplex operations according to some aspects of the disclosure. TDD allows two endpoints to communicate with each other in different traffic directions on a given channel using time-division multiplexing. For example, a scheduling entity <NUM> (e.g., a base station or gNB) can communicate with a scheduled entity <NUM> (e.g., UE) using a fixed or predetermined uplink-to-downlink duration ratio in a TDD frequency band, channel, or bandwidth part (BWP). In one exemplary TDD frequency band <NUM>, one uplink (UL) slot <NUM> is time-multiplexed with three downlink (DL) slots <NUM>. In some cases, the uplink latency may be too long for certain latency-sensitive services or applications.

To improve the latency, the scheduled entity may communicate with the scheduling entity using a sub-band FD mode in which DL and UL transmissions can occur simultaneously using different frequencies, bands, sub-bands, or BWPs. In one example, a frequency band <NUM> (e.g., <NUM> band) may be divided into multiple sub-bands (e.g., sub-band <NUM>, sub-band <NUM>, and sub-band <NUM>), and each sub-band may be assigned for UL or DL to support FD communication using different sub-bands to enable simultaneous UL and DL transmissions. In some aspects, the frequency band <NUM> may be a TDD band. In some aspects, the sub-bands may have equal bandwidth. In some aspects, the sub-bands may have different bandwidths. This use of sub-bands for FD communication may be referred to herein as sub-band FDD, which is different from FD communication using separate FDD bands (paired spectrum). For example, paired FDD bands may be used for UL and DL transmissions, respectively, to support FD communication.

In some aspects, a UE can flexibly select different FDD modes due to different power and/or performance requirements. <FIG> is a diagram illustrating some examples of different FDD modes. In a first FDD example <NUM> (FD FDD), a DL transmission can use a first band F1, and a UL transmission can use a second band F2. In a second FDD example <NUM> (HD FDD), UL and DL transmissions are time-multiplexed and use different frequency bands for UL and DL transmissions, respectively. For example, a DL transmission can use F1, and a UL transmission can use F2. In one aspect, the frequency bands F1 and F2 may be paired FDD spectrum. In one aspect, the frequency bands F1 and F2 may be TDD sub-bands. In some aspects, HD FDD may be implemented with complementary user groupings <NUM> to improve bandwidth utilization. In one aspect, DL transmissions of group A UEs and group B UEs are time-multiplexed on F1, and UL transmissions of group A UEs and group B UEs are time-multiplexed on F2. Using complementary user groupings, a group A UE can transmit signals and a group B UE can receive signals in the same radio frame; or a group A UE can receive signals and a group B UE can transmit in the same radio frame. In some aspects, the FD FDD and HD FDD modes can be implemented using TDD sub-bands or paired FDD spectrum/bands. In some aspects, FD FDD may be implemented using other FDD schemes, for example, inter-band FDD and other sub-band FDD modes different from that illustrated in <FIG> and <FIG>.

For example, the UE can use the FD FDD mode to reduce latency and use the HD FDD mode to reduce power consumption, for example, in a radio resource control (RRC) connected state. In HD FDD, the UE only transmits or receives signals to/from the network in a time slot. In one aspect, the UE can use the HD FDD mode on paired spectrum. In one example, the paired spectrum may include different FDD bands. In one aspect, the UE can use the HD FDD mode on sub-bands of a TDD band. In the HD FDD mode, the UE can save power by not monitoring/decoding downlink channels and not measuring downlink signals when performing UL transmission. In one example, the downlink channels may include PDCCH and PDSCH. In one example, the downlink signals may include an SS block and CSI-RS. In some aspects, the UE can use the FD FDD mode to provide more bandwidth and/or lower latency for mission critical traffic (e.g., VOIP, V2V) and/or coverage enhancement. Therefore, a UE capable of switching between FD FDD and HD FDD modes can intelligently improve power saving and provide on-demand service to latency-sensitive service and/or coverage enhancement when needed, as compared to HD FDD mode only UEs.

In this disclosure, a UE that can support and flexibly switch among multiple FDD modes (e.g., FD FDD and HD FDD modes) is called a FD FDD capable UE. In some aspects, a FD FDD capable UE can use paired spectrum or sub-bands (e.g., TDD sub-bands) for simultaneous UL and DL communication. The UE can indicate its ability of using different FDD modes (e.g., HD FDD and FD FDD) and flexible switching between the FDD modes as a UE capability.

<FIG> is a diagram illustrating signaling between a scheduling entity <NUM> and a UE <NUM> for signaling support of FDD modes switching according to the invention. The scheduling entity <NUM> may be any of the scheduling entities, gNBs, or base stations described herein, for example in relation to <FIG> and <FIG>. The UE <NUM> may be any of the UEs or scheduled entities described herein, for example in relation to <FIG> and <FIG>. The scheduling entity <NUM> (e.g., gNB) is configured to transmit a UE capability inquiry <NUM> to the UE <NUM> that may have established an RRC connection (e.g., RRC connected mode) with the scheduling entity. The UE capability inquiry <NUM> (e.g., UECapabilityEnquiry message) can specify which information the scheduling entity wants to obtain from the UE. In response, the UE <NUM> is configured to report the requested capability information. After knowing the UE capability, the scheduling entity <NUM> can make the appropriate scheduling for the UE in various scenarios. In one example, the UE capability inquiry <NUM> may be included in an RRC message that requests the UE to report its capability of supporting various FDD modes, for example, one or more FD FDD modes and a HD FDD mode.

In response to the UE capability inquiry <NUM>, the UE <NUM> is configured to transmit a UE capability report <NUM> to the scheduling entity <NUM>. For example, the UE can transmit an RRC message including the UE capability report <NUM> (e.g., a UECapabilityInformation message). In some aspects, the UE capability report <NUM> may indicate supported frequency bands and FDD modes (e.g., one or more FD FDD modes and a HD FDD mode) supported by the UE. The UE capability report <NUM> can also indicate the UE's capability of switching between the supported FDD modes, for example, between different FD FDD modes or between a FD FDD mode and a HD FDD mode.

In one aspect, the UE capability report <NUM> can indicate that the UE <NUM> can support various FDD modes that have different ratios of UL and DL duration per slot/symbol. In one aspect, the UE capability report <NUM> can indicate that the UE <NUM> can support various FDD modes that are different in DL bandwidth (e.g., BWP) and/or UL bandwidth (e.g., BWP). In one aspect, the UE capability report <NUM> can indicate that the UE <NUM> can support various FDD modes that are different in flexible slot/symbol support. In one aspect, the UE capability report <NUM> can indicate that the UE can support various FDD modes that are different in discontinuous reception (DRX) and/or discontinuous transmission (DTX) configurations. In one aspect, the UE capability report <NUM> can indicate that the UE can support various FDD modes that are different in DL and/or UL reference signal resources. Examples of DL reference signals include, but are not limited to, CSI-RS, DM-RS, tracking reference signal (TRS) and PT-RS. Examples of UL reference signals include, but are not limited to, SRS, DM-RS and PT-RS. In one aspect, the UE capability report <NUM> can indicate that the UE can support various FDD modes that have different configurations of CSI, radio link monitoring (RLM), and/or radio resource management (RRM).

Based on the UE capability report <NUM>, the scheduling entity <NUM> is configured to transmit FDD mode configuration information <NUM> to the UE. In one aspect, the FDD mode configuration information <NUM> can include the slot formats, BWP, scheduling offsets, application delay, etc., for one or more FDD modes. In one example, the scheduling entity <NUM> can transmit the FDD mode configuration information <NUM> in an RRC message. In some aspects, the FDD mode configuration information <NUM> can indicate the FDD mode (e.g., FD FDD and HD FDD) selected for communication between the scheduling entity and UE and related configuration information. In some aspects, the scheduling entity <NUM> can transmit timing or a timer configuration for switching between the FDD modes in at least one of system information (e.g., MIB, SIB) or an RRC message.

<FIG> is a diagram illustrating exemplary FDD modes switching according to some aspects of the disclosure. In some aspects, a scheduled entity <NUM> (e.g., UE) is capable of communicating with a network (e.g., one or more scheduling entities <NUM> or gNBs) using different FDD modes (e.g., a FD FDD mode <NUM> and one or more HD FDD modes <NUM> and <NUM>). In some aspects, the UE is configured to support two or more HD FDD modes that have different configurations. In some aspects, different HD FDD modes are different in terms of UL/DL slot/symbol ratio, numerology, UL/DL bandwidth (e.g., BWP), slot/symbol duration, DRX/DTX parameters, UL/DL reference signal resources, and/or measurement and reporting configuration. For example, a UE may use different measurement and reporting configurations for CSI, RLM, and/or RRM, in different HD FDD modes (e.g., HD FDD mode <NUM> and HD FDD mode <NUM>).

In one aspect, a UE is configured to switch from the FD FDD mode <NUM> to a first HD FDD mode <NUM> (e.g., the HD FDD mode <NUM>). In one aspect, the UE is configured to switch from the first HD FDD mode <NUM> to the FD FDD mode <NUM> or a second HD FDD mode <NUM> (e.g., HD FDD mode <NUM>). In one aspect, the UE is configured to switch from second HD FDD mode <NUM> to the first HD FDD mode <NUM> or the FD FDD mode <NUM>. The switching between the FDD modes can be initiated by the scheduling entity or requested by the UE. The switching between the FDD modes can be dynamic or semi-persistent. For example, dynamic switching between FDD modes allows the UE to change the FDD mode in use in each subframe. In some aspects, the scheduling entity can initiate dynamic switching between FDD modes using a media access control (MAC) control element (CE) (PDSCH) and/or DCI (PDCCH). In some aspects, the UE can request dynamic switching between FDD modes using a MAC CE (PUSCH) and/or UCI (PUCCH or PUSCH). In one aspect, the scheduling entity may configure the UE to switch between the FDD modes when certain conditions (e.g., latency or bandwidth requirements) are met. In one example, the scheduling entity can set a timer (e.g., timer <NUM>) that can trigger the UE to switch between the FD FDD mode and one or more HD FDD modes according to a predetermined pattern or periodicity. Using different FDD modes, the UE can achieve power saving and provide on-demand service to latency-sensitive service and/or coverage enhancement when needed. In one example, the UE can have a lower power consumption and/or higher latency in the first HD FDD mode <NUM>, but the UE can have higher power consumption and/or lower latency in the second HD FDD mode <NUM> or FD FDD mode <NUM>.

<FIG> is a diagram illustrating a first exemplary HD FDD mode radio frame <NUM> according to some aspects of the disclosure. The radio frame <NUM> can have various combinations of UL, DL, and flexible slots in different HD FDD modes (e.g., HD FDD mode <NUM> and HD FDD mode <NUM> in <FIG>). In one example, the radio frame <NUM> may include six DL slots <NUM> using a first band (F1), three UL slots <NUM> using a second band (F2), and one flexible (F) slot <NUM> using F1 or F2. The flexible slot can include one or more flexible symbols that can be configured as DL, UL, DRX, or DTX symbols.

<FIG> is a diagram illustrating a second exemplary HD FDD mode radio frame <NUM>. In this example, the radio frame <NUM> may include two DL slots <NUM> using a first band (F1), six UL slots <NUM> using a second band (F2), and two flexible slots <NUM> using F1 or F2. Each flexible (F) slot <NUM> includes one or more symbols that can be configured as DL, UL, DRX, or DTX symbols. In some aspects, a HD FDD radio frame may have more or less UL, DL, and/or flexible slots than those shown in <FIG> and <FIG>.

<FIG> is a diagram illustrating an example of gNB-initiated FDD mode switching according to some aspects of the disclosure. A gNB <NUM> can communicate with a UE <NUM> using a first FDD mode <NUM>. The gNB <NUM> can be any of the scheduling entities or base stations described above in relation to <FIG> and <FIG>. The UE <NUM> can be any of the scheduled entities or UEs described above in relation to <FIG> and <FIG>. In some aspects, the first FDD mode <NUM> may be a FD FDD mode or a HD FDD mode as described above in relation to <FIG>. The gNB <NUM> can dynamically initiate FDD mode switching <NUM>, for example, to change the power consumption and/or performance of the UE. To that end, the gNB <NUM> can transmit a FDD mode switching command <NUM> to the UE <NUM>. In one example, the gNB <NUM> can transmit the FDD mode switching command <NUM> in a MAC CE on a PDSCH to facilitate dynamic switching of FDD modes. In another example, the gNB <NUM> can transmit the FDD mode switching command <NUM> in a DCI on a PDCCH to facilitate dynamic switching of FDD modes.

After receiving the FDD mode switching command <NUM>, the UE <NUM> can switch to a second FDD mode <NUM> to communicate with the gNB <NUM>. The second FDD mode can be different from the first FDD mode in at least one of: an uplink-to-downlink time duration ratio; an uplink bandwidth and downlink bandwidth configuration; a time duration of a flexible slot of the HD FDD mode; a time duration for a flexible symbol of the HD FDD mode; a DRX configuration; a DTX configuration; a downlink reference signal configuration; an uplink reference signal configuration; a radio link management configuration; or a radio resource management configuration.

<FIG> is a diagram illustrating an example of UE initiated FDD mode dynamic switching according to some aspects of the disclosure. A gNB <NUM> can communicate with a UE <NUM> using a first FDD mode <NUM>. The gNB <NUM> can be any of the scheduling entities or base stations described above in relation to <FIG> and <FIG>. The UE <NUM> can be any of the scheduled entities or UEs described above in relation to <FIG> and <FIG>. In some aspects, the first FDD mode <NUM> may be a FD FDD mode or a HD FDD mode as described above in relation to <FIG>. The UE <NUM> can dynamically initiate FDD mode switching <NUM>, for example, to change the latency, power consumption, and/or performance of the UE. To that end, the UE <NUM> can transmit a FDD mode switching command <NUM> to the gNB <NUM>. In one example, the UE <NUM> can transmit the FDD mode switching command <NUM> in a MAC CE on a PUSCH. In another example, the UE <NUM> can transmit the FDD mode switching command <NUM> in a UCI on a PUCCH.

After receiving the FDD mode switching command <NUM>, the gNB <NUM> can switch to a second FDD mode <NUM> to communicate with the UE <NUM>. The second FDD mode can be different from the first FDD mode in at least one of: an uplink-to-downlink time duration ratio; an uplink bandwidth and downlink bandwidth configuration; a time duration of a flexible slot of the HD FDD mode; a time duration for a flexible symbol of the HD FDD mode; a DRX configuration; a DTX configuration; a downlink reference signal configuration; an uplink reference signal configuration; a radio link management configuration; or a radio resource management configuration.

<FIG> is a diagram illustrating a FDD mode switching timeline according to some aspects of the disclosure. When a scheduling entity (e.g., gNB) and a UE dynamically switch the FDD mode in use, for example, as described above in relation to <FIG> and <FIG>, a scheduling offset (e.g., a timing offset) may be used to account for the time needed to switch from a current FDD mode <NUM> (e.g., FD FDD or HD FDD) to a new FDD mode <NUM> (e.g., HD FDD or FD FDD). In one example, the scheduling entity can signal the scheduling offset <NUM> in a DCI in a PDCCH or a MAC CE in a PDSCH. In one example, the scheduling entity can signal the scheduling offset in a FDD mode switching command <NUM>. In one example, the UE can signal the scheduling offset in a FDD mode switching command <NUM>. In some aspects, the scheduling offset may be a predetermined time duration (e.g., k slots) between the FDD mode switching signaling and the start of the slot that uses the new FDD mode. A minimum scheduling offset kmin (e.g., in slots) can be used as the lower bound of the scheduling offset (k). In one aspect, kmin can be preconfigured, for example, specified in a communication standard that governs the communication between the scheduling entity and UE. In one aspect, the scheduling entity can configure kmin, for example, indicating kmin in system information (SI) and/or an RRC message. In one example, the scheduling entity can signal the slot index of the slot in which the new FDD mode <NUM> can start. For example, the scheduling entity can explicitly signal the slot index as a timing indicator k, where k ≥ kmin, and kmin can be determined by the minimum SCS of the active DL BWP for the current FDD mode and new FDD mode, respectively.

<FIG> is a block diagram illustrating an example of a hardware implementation for a scheduled entity <NUM> employing a processing system <NUM>. For example, the scheduled entity <NUM> may be a UE as illustrated in any one or more of <FIG>, <FIG>, <FIG>, <FIG>, and/or <NUM>.

The scheduled entity <NUM> may be implemented with a processing system <NUM> that includes one or more processors <NUM>. Examples of processors <NUM> include microprocessors, microcontrollers, digital signal processors (DSPs), field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionality described throughout this disclosure. In various examples, the scheduled entity <NUM> may be configured to perform any one or more of the functions described herein. That is, the processor <NUM>, as utilized in a scheduled entity <NUM>, may be used to implement any one or more of the processes and procedures described herein, for example, illustrated in <FIG>, <FIG>, <FIG>, and <FIG>.

The processor <NUM> may in some instances be implemented via a baseband or modem chip and in other implementations, the processor <NUM> may include a number of devices distinct and different from a baseband or modem chip (e.g., in such scenarios as may work in concert to achieve examples discussed herein). And as mentioned above, various hardware arrangements and components outside of a baseband modem processor can be used in implementations, including RF-chains, power amplifiers, modulators, buffers, interleavers, adders/summers, etc..

In this example, the processing system <NUM> may be implemented with a bus architecture, represented generally by the bus <NUM>. The bus <NUM> may include any number of interconnecting buses and bridges depending on the specific application of the processing system <NUM> and the overall design constraints. The bus <NUM> communicatively couples together various circuits including one or more processors (represented generally by the processor <NUM>), a memory <NUM>, and computer-readable media (represented generally by the computer-readable medium <NUM>). The bus <NUM> may also link various other circuits such as timing sources, peripherals, voltage regulators, and power management circuits, which are well known in the art, and therefore, will not be described any further. A bus interface <NUM> provides an interface between the bus <NUM> and a transceiver <NUM>. The transceiver <NUM> provides a communication interface or means for communicating with various other apparatus over a transmission medium. Depending upon the nature of the apparatus, a user interface <NUM> (e.g., keypad, display, speaker, microphone, joystick) may also be provided.

One or more processors <NUM> in the processing system may execute software. The software may reside on a computer-readable medium <NUM>. The computer-readable medium <NUM> may be a non-transitory computer-readable medium. A non-transitory computer-readable medium includes, by way of example, a magnetic storage device (e.g., hard disk, floppy disk, magnetic strip), an optical disk (e.g., a compact disc (CD) or a digital versatile disc (DVD)), a smart card, a flash memory device (e.g., a card, a stick, or a key drive), a random access memory (RAM), a read only memory (ROM), a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), a register, a removable disk, and any other suitable medium for storing software and/or instructions that may be accessed and read by a computer. The computer-readable medium <NUM> may reside in the processing system <NUM>, external to the processing system <NUM>, or distributed across multiple entities including the processing system <NUM>. The computer-readable medium <NUM> may be embodied in a computer program product. By way of example, a computer program product may include a computer-readable medium in packaging materials. Those skilled in the art will recognize how best to implement the described functionality presented throughout this disclosure depending on the particular application and the overall design constraints imposed on the overall system.

In some aspects of the disclosure, the processor <NUM> may include circuitry configured for various functions, including, for example, wireless communication using various FDD modes (e.g., one or more FD FDD and HD FDD modes) and FDD mode switching methods. For example, the circuitry may be configured to implement one or more of the functions and processes described in relation to <FIG>.

In some aspects of the disclosure, the processor <NUM> may include communication and processing circuitry <NUM> configured for various functions, including for example communicating with scheduling entities (e.g., gNB) or any other entity, such as, for example, local infrastructure via the scheduling entities. In some examples, the communication and processing circuitry <NUM> may include one or more hardware components that provide the physical structure that performs processes related to wireless communication (e.g., signal reception and/or signal transmission) and signal processing (e.g., processing a received signal and/or processing a signal for transmission). For example, the communication and processing circuitry <NUM> may include one or more transmit/receive chains. In addition, the communication and processing circuitry <NUM> may be configured to process and transmit uplink traffic and uplink control messages (e.g., similar to uplink traffic <NUM> and uplink control <NUM> of <FIG>), receive and process downlink traffic and downlink control messages (e.g., similar to downlink traffic <NUM> and downlink control <NUM>). The communication and processing circuitry <NUM> may further be configured to execute communication and processing instructions (software) <NUM> stored on the computer-readable medium <NUM> to implement one or more functions described herein. For example, the communication and processing circuitry <NUM> may be configured to use various FDD modes for wireless communications.

In some implementations where the communication involves receiving information, the communication and processing circuitry <NUM> may obtain information from a component of the wireless communication device <NUM> (e.g., from the transceiver <NUM> that receives the information via radio frequency signaling or some other type of signaling suitable for the applicable communication medium), process (e.g., decode) the information, and output the processed information. For example, the communication and processing circuitry <NUM> may output the information to another component of the processor <NUM>, to the memory <NUM>, or to the bus interface <NUM>. In some examples, the communication and processing circuitry <NUM> may receive one or more of signals, messages, other information, or any combination thereof. In some examples, the communication and processing circuitry <NUM> may receive information via one or more channels. In some examples, the communication and processing circuitry <NUM> may include functionality for a means for receiving. In some examples, the communication and processing circuitry <NUM> may include functionality for a means for processing, including a means for demodulating, a means for decoding, etc..

In some implementations where the communication involves sending (e.g., transmitting) information, the communication and processing circuitry <NUM> may obtain information (e.g., from another component of the processor <NUM>, the memory <NUM>, or the bus interface <NUM>), process (e.g., modulate, encode, etc.) the information, and output the processed information. For example, the communication and processing circuitry <NUM> may output the information to the transceiver <NUM> (e.g., that transmits the information via radio frequency signaling or some other type of signaling suitable for the applicable communication medium). In some examples, the communication and processing circuitry <NUM> may send one or more of signals, messages, other information, or any combination thereof. In some examples, the communication and processing circuitry <NUM> may send information via one or more channels. In some examples, the communication and processing circuitry <NUM> may include functionality for a means for sending (e.g., a means for transmitting). In some examples, the communication and processing circuitry <NUM> may include functionality for a means for generating, including a means for modulating, a means for encoding, etc..

In some aspects, the processor <NUM> may include FDD mode switching circuitry <NUM> that can be configured to perform various functions and processes used to switch between different FDD modes, for example, a FD FDD mode and one or more HD FDD modes that can be used for wireless communication between the scheduled entity <NUM> and a scheduling entity (e.g., gNB or base station). In one example, the FDD mode switching circuitry <NUM> may determine a triggering condition to switch between two FDD modes (e.g., an FD FDD mode and one or more HD FDD modes). In some examples, the FDD mode switching circuitry <NUM> may include one or more hardware components that provide the physical structure that performs processes related to FDD mode switching in wireless communication. In some aspects, the scheduled entity may maintain a timer <NUM> (e.g., in memory <NUM>) for determining timing for switching between different FDD modes. The FDD mode switching circuitry <NUM> may further be configured to execute FDD mode switching instructions (software) <NUM> stored on the computer-readable medium <NUM> to implement one or more functions described herein.

<FIG> is a flow chart illustrating an exemplary process <NUM> for wireless communication using dynamic FDD modes switching in accordance with some aspects of the present disclosure. As described below, some or all illustrated features may be omitted in a particular implementation within the scope of the present disclosure, and some illustrated features may not be required for implementation of all embodiments. In some examples, the process <NUM> may be carried out by the scheduled entity <NUM> (e.g., UE) illustrated in <FIG>. In some examples, the process <NUM> may be carried out by any suitable apparatus or means for carrying out the functions or algorithm described below.

At block <NUM>, a UE is configured to communicate with a scheduling entity (e.g., gNB or base station) in a first FDD mode among a plurality of FDD modes. The plurality of FDD modes includes at least one FD FDD mode and at least one HD FDD mode. In one example, the communication and processing circuitry <NUM> can provide a means for communicating with the scheduling entity in the first FDD mode (e.g., a FD FDD mode or a HD FDD mode). In some aspects, the first FDD mode can use a first frequency band for an uplink transmission and a second frequency band for a downlink transmission, in a first configuration. In one aspect, the first FDD mode can be a HD FDD mode in which UL and DL transmissions are time-multiplexed and use different bands or sub-bands (e.g., bands F1 and F2 described in relation to <FIG>). In one example, the first frequency band and the second frequency band may be paired FDD spectrum. In one example, the first frequency band and the second frequency band may be separated by a duplex distance to avoid interference. In one example, the first frequency band and second frequency band may be sub-bands of a TDD band. In one example, the first frequency band and second frequency band may correspond to different bandwidths or BWPs.

At block <NUM>, the UE is configured to switch from the first FDD mode to a second FDD mode of the plurality of FDD modes, in response to a first triggering condition corresponding to at least one of a power consumption or a performance level of the UE. In some aspects, the UE can dynamically switch between FDD modes between different subframes or slots without using RRC signaling. In one aspect, the FDD mode switching circuit <NUM> can provide a means for switching the UE from the first FDD mode (e.g., a first HD FDD mode) to the second FDD mode (e.g., a FD FDD mode or a second HD FDD mode). In some aspects, the triggering condition may relate to a communication latency between the UE and the scheduling entity, power efficiency of the UE, signal coverage, system loading information, traffic pattern, QoS requirements, etc. In one aspect, the UE may determine the triggering condition using a process <NUM> described below in relation to <FIG>.

In some aspects, the UE is configured to determine the triggering condition in coordination with the scheduling entity. In one aspect, the UE is configured to receive a MAC CE on a PDSCH that causes the UE to switch the FDD mode (e.g., from the HD FDD mode to the FD FDD mode). In one aspect, the UE is configured to receive a DCI on a PDCCH that causes the UE to switch the FDD mode (e.g., from the first FDD mode to the second FDD mode). In one aspect, a scheduling entity may signal the UE to switch between the first FDD mode and the second FDD mode based on a predetermined time duration or timer (e.g., timer <NUM>). For example, the UE may receive timer information in system information (SI) and/or RRC signaling transmitted by the scheduling entity. The timer may cause the UE to switch between FDD modes (e.g., the first FDD mode and the second FDD mode) according to a predetermined pattern or periodicity.

At block <NUM>, the UE is configured to communicate with the scheduling entity in the second FDD mode. In some aspects, the second FDD mode can use the first frequency band for the uplink transmission and the second frequency band for the downlink transmission, in a second configuration that is different from the first configuration. In one aspect, the communication and processing circuitry <NUM> can provide a means for communicating with the scheduling entity using the second FDD mode. In one aspect, the second FDD mode may be a FD FDD mode in which the UE can perform UL and DL communication simultaneously using different frequency bands, for example, paired FDD spectrum or TDD sub-bands (e.g., see <FIG>).

In some aspects, the UE may switch back to the first FDD mode (e.g., HD FDD mode) when a predetermined triggering condition is met. In one example, the UE can switch back to the HD FDD mode to reduce power consumption. In one example, the UE may switch to the HD FDD mode when the communication latency or coverage requirement is reduced.

<FIG> is a flow chart illustrating an exemplary process <NUM> for determining a triggering condition for switching between different FDD modes according to some aspects of the disclosure. In some aspects, the process <NUM> may be performed by any of the scheduling entities or UEs in <FIG>, <FIG>, <FIG>, <FIG>, and/or <NUM>. In some aspects, a UE may perform the process <NUM> to determine a triggering condition in coordination with a scheduling entity.

At block <NUM>, a scheduling entity and a UE may communicate with each other using a first FDD mode (e.g., HD FDD mode). At decision block <NUM>, if the scheduling entity or the UE determines to reduce communication latency between the scheduling entity and the UE, the scheduling entity or the UE can initiate a FDD mode switch. For example, at block <NUM>, the scheduling entity and the UE can switch to use a second FDD mode that is different from the first FDD mode. For example, the second FDD mode may be a FD FDD mode that has a lower latency.

At decision block <NUM>, if the scheduling entity or the UE determines to enhance, improve, or increase communication signal coverage, the scheduling entity or the UE can initiate a FDD mode switch. For example, at block <NUM>, the scheduling entity and the UE can switch to use a second FDD mode (e.g., FD FDD mode) that has better signal coverage.

At decision block <NUM>, the scheduling entity or the UE can determine to use a FDD mode for prioritizing or improving the power efficiency of the UE. In one aspect, at block <NUM>, the scheduling entity and the UE can initiate a FDD mode switch to a FD FDD mode when power efficiency is not prioritized. In one aspect, the scheduling entity and the UE can continue to use the HD FDD mode if power efficiency is prioritized. In other aspects, the process of <FIG> may be modified in various different ways to add, remove, and/or rearrange the conditions used to determine the switching between FDD modes (e.g., FD FDD and HD FDD modes). In one example, two triggering conditions for FDD mode switching can be different in at least one of: communication latency; power efficiency; traffic pattern and QoS requirements; system loading information; or signal coverage. In some aspects, the scheduling entity and the UE can use the process <NUM> to switch between different HD FDD modes (e.g., HD FDD mode <NUM> and HD FDD mode <NUM>) that are different, for example, in power efficiency, latency, and/or signal coverage.

<FIG> is a flow chart illustrating an exemplary process <NUM> for switching between different FDD modes according to a periodicity of the FDD modes. In some aspects, the process <NUM> is performed by any of the scheduling entities or UEs in <FIG>, <FIG>, <FIG>, <FIG>, and/or <NUM>. At block <NUM>, a UE is configured to receive a periodicity of a first FDD mode and a second FDD mode in at least one of system information or a radio resource control message. In some aspects, the periodicity may be a predetermined periodicity specified in a communication standard (e.g., <NUM> NR) that governs the communication between the scheduling entity and UE. In some aspects, a scheduling entity (e.g., gNB) can configure the periodicity of the FDD modes. At block <NUM>, the UE is configured to switch between the first FDD mode and the second FDD mode according to the periodicity of the first FDD mode and the second FDD mode. In one aspect, the FDD mode switching circuit <NUM> can provide a means for switching between the first FDD mode and the second FDD mode according to the periodicity of the first FDD mode and the second FDD mode. According to the periodicity, the UE and the scheduling entity can communicate using the first FDD mode in a first predetermined number of subframes/slots, and using the second FDD mode in a second predetermined number of subframes/slots.

<FIG> is a block diagram illustrating an example of a hardware implementation for a scheduling entity <NUM> employing a processing system <NUM>. For example, the scheduling entity <NUM> may be a scheduling entity (e.g., gNB) as illustrated in any one or more of <FIG>, <FIG>, <FIG>, <FIG>, and/or <NUM>.

The processing system <NUM> may be substantially the same as the processing system <NUM> illustrated in <FIG>, including a bus interface <NUM>, a bus <NUM>, memory <NUM>, a processor <NUM>, and a computer-readable medium <NUM>. Furthermore, the scheduling entity <NUM> may include an optional user interface <NUM> and a transceiver <NUM> substantially similar to those described above in <FIG>. That is, the processor <NUM>, as utilized in a scheduling entity <NUM>, may be used to implement any one or more of the processes and procedures described and illustrated in <FIG>, <FIG>, <FIG>, <FIG>, and <FIG>. In some aspects of the disclosure, the processor <NUM> may include circuitry configured for various functions, including, for example, wireless communication using various FDD modes (e.g., FD FDD and HD FDD modes) and FDD mode switching methods.

In some aspects of the disclosure, the processor <NUM> may include communication and processing circuitry <NUM> configured for various functions, including for example communicating with scheduled entities (e.g., UE). In some examples, the communication and processing circuitry <NUM> may include one or more hardware components that provide the physical structure that performs processes related to wireless communication (e.g., signal reception and/or signal transmission) and signal processing (e.g., processing a received signal and/or processing a signal for transmission). For example, the communication and processing circuitry <NUM> may include one or more transmit/receive chains. In addition, the communication and processing circuitry <NUM> may be configured to receive and process uplink traffic and uplink control messages (e.g., similar to uplink traffic <NUM> and uplink control <NUM> of <FIG>), transmit and process downlink traffic and downlink control messages (e.g., similar to downlink traffic <NUM> and downlink control <NUM>). The communication and processing circuitry <NUM> may further be configured to execute communication and processing instructions (software) <NUM> stored on the computer-readable medium <NUM> to implement one or more functions described herein. For example, the communication and processing circuitry <NUM> may be configured to use various FDD modes (e.g., FD FDD and HD FDD modes) for wireless communications.

In some aspects, the processor <NUM> may include a FDD mode switching circuitry <NUM> that can be configured to perform various functions and processes used to switch between different FDD modes, for example, a FD FDD mode and one or more HD FDD modes that can be used for wireless communication between the scheduling entity <NUM> and a scheduled entity (e.g., UE). In some examples, the FDD mode switching circuitry <NUM> may include one or more hardware components that provide the physical structure that performs processes related to dynamic FDD mode switching in wireless communication. In some examples, the scheduling entity can use the FDD mode switching circuitry <NUM> to cause the UE to dynamically switch between different FDD modes in different subframes. The FDD mode switching circuitry <NUM> may further be configured to execute FDD mode switching instructions (software) <NUM> stored on the computer-readable medium <NUM> to implement one or more functions described herein.

<FIG> is a flow chart illustrating an exemplary process <NUM> for wireless communication using multiple FDD modes in accordance with some aspects of the present disclosure. As described below, some or all illustrated features may be omitted in a particular implementation within the scope of the present disclosure, and some illustrated features may not be required for implementation of all embodiments. In some examples, the process <NUM> may be carried out by the scheduling entity <NUM> illustrated in <FIG>. In some examples, the process <NUM> may be carried out by any suitable apparatus or means for carrying out the functions or algorithm described below.

At block <NUM>, a scheduling entity (e.g., gNB) is configured to communicate with a UE in a first FDD mode among a plurality of FDD modes. The plurality of FDD modes includes at least one FD FDD mode and at least one HD FDD mode. In one example, the communication and processing circuitry <NUM> can provide a means for communicating with the UE in the first FDD mode (e.g., a FD FDD mode or a HD FDD mode). In some aspects, the first FDD mode can use a first frequency band for an uplink transmission and a second frequency band for a downlink transmission, in a first configuration. In one aspect, the first FDD mode can be a HD FDD mode in which UL and DL transmissions are time-multiplexed and use different bands or sub-bands (e.g., bands F1 and F2 described in relation to <FIG>). In one example, the first frequency band and second frequency band may be paired FDD spectrum. In one example, the first frequency band and second frequency band may be sub-bands of a TDD band. In one example, the first frequency band and the second frequency band may correspond to different bandwidths or BWPs.

At block <NUM>, the scheduling entity is configured to switch from the first FDD mode to a second FDD mode of the plurality of FDD modes, in response to a first triggering condition corresponding to at least one of a power consumption or a performance level of the UE. In one aspect, the FDD mode switching circuit <NUM> can provide a means for switching from the first FDD mode (e.g., a first HD FDD mode) to the second FDD mode (e.g., a FD FDD mode or a second HD FDD mode). For example, scheduling entity can use the FDD mode switching circuitry <NUM> to transmit a control message (e.g., DCI or MAC CE) to the UE to initiate FDD mode switching in response to the first triggering condition.

In some aspects, the triggering condition may relate to a communication latency between the UE and the scheduling entity, power efficiency of the UE, signal coverage, system loading information, traffic pattern, QoS requirements, etc. In one aspect, the scheduling entity may determine the triggering condition using the process <NUM> described above in relation to <FIG>. In some aspects, the scheduling entity may determine the triggering condition in coordination with the UE. In one aspect, the scheduling entity configured to transmit a MAC CE on a PDSCH that causes the UE to switch from the HD FDD mode to the FD FDD mode. In one aspect, the scheduling entity is configured to transmit a DCI on a PDCCH that causes the UE to switch from the first FDD mode to the second FDD mode. In one aspect, a scheduling entity may signal the UE to switch between the first FDD mode and the second FDD mode based on a predetermined time duration or timer (e.g., timer <NUM>). For example, the scheduling entity may transmit timer information in system information (SI) and/or RRC signaling. The timer may cause the UE to switch between the first FDD mode and the second FDD mode according to a predetermined pattern or periodicity.

At block <NUM>, the scheduling entity is configured to communicate with the UE in the second FDD mode. In one example, the communication and processing circuitry <NUM> can provide a means for communicating with the UE in the second FDD mode. In some aspects, the second FDD mode can use the first frequency band for the uplink transmission and the second frequency band for the downlink transmission, in a second configuration that is different from the first configuration. In one aspect, the second FDD mode may be a FD FDD mode in which the scheduling entity can perform UL and DL communication simultaneously using different frequency bands, for example, paired FDD spectrum or TDD sub-bands.

In some aspects, the scheduling entity is configured to switch back to the first FDD mode (e.g., HD FDD mode) when a predetermined triggering condition is met. In one example, the scheduling entity can switch back to the HD FDD mode to reduce power consumption of the UE. In one example, the scheduling entity may switch to the HD FDD mode when the communication latency or coverage requirement is reduced.

<FIG> is a flow chart illustrating an exemplary process <NUM> for switching between different FDD modes according to a periodicity of the FDD modes. In some aspects, the process <NUM> may be performed by any of the scheduling entities or UEs in <FIG>, <FIG>, <FIG>, <FIG>, and/or <NUM>. At block <NUM>, a scheduling entity can transmit a periodicity of a first FDD mode and a second FDD mode in at least one of system information or a radio resource control message. In some aspects, the periodicity may be a predetermined periodicity specified in a communication standard (e.g., <NUM> NR) that governs the communication between the scheduling entity and a UE. At block <NUM>, the scheduling entity can switch or cause the UE to switch between the first FDD mode and the second FDD mode according to the periodicity of the first FDD mode and the second FDD mode. In one aspect, the FDD mode switching circuit <NUM> can provide a means for switching between the first FDD mode and the second FDD mode according to the periodicity of the first FDD mode and the second FDD mode.

The scope of the present invention is defined by the scope of the appended claims. Reference to an element in the singular is not intended to mean "one and only one" unless specifically so stated, but rather "one or more. As an example, "at least one of: a, b, or c" is intended to cover: a; b; c; a and b; a and c; b and c; and a, b and c. Evolution-Data Optimized (EV-DO).

Claim 1:
A user equipment, UE (<NUM>), for wireless communication, comprising:
a transceiver configured to use a plurality of frequency-division duplexing, FDD, modes (<NUM>, <NUM>, <NUM>) for wireless communication, the plurality of FDD modes (<NUM>, <NUM>, <NUM>) comprising at least one full-duplex, FD, FDD mode (<NUM>) and at least one half-duplex, HD, FDD mode (<NUM>, <NUM>);
a memory; and
a processor connected with the transceiver and the memory,
wherein the processor and the memory are configured to:
communicate, using the transceiver, with a scheduling entity (<NUM>) in a first FDD mode (<NUM>, <NUM>, <NUM>) among the plurality of FDD modes (<NUM>, <NUM>, <NUM>);
receive, using the transceiver, from the scheduling entity (<NUM>), at least one of a media access control, MAC, control element, CE, or downlink control information, DCI, configured to trigger the UE (<NUM>) to switch from the first FDD mode (<NUM>, <NUM>, <NUM>) to the second FDD mode (<NUM>, <NUM>, <NUM>), in response to a first triggering condition corresponding to at least one of a power consumption or a performance level of the UE (<NUM>);
switch from the first FDD mode (<NUM>, <NUM>, <NUM>) to a second FDD mode (<NUM>, <NUM>, <NUM>) of the plurality of FDD modes (<NUM>, <NUM>, <NUM>), wherein the first FDD mode (<NUM>, <NUM>, <NUM>) is different from the second FDD mode (<NUM>, <NUM>, <NUM>); and
communicate, using the transceiver, with the scheduling entity (<NUM>) in the second FDD mode (<NUM>, <NUM>, <NUM>).