Method and apparatus for wireless communication

Abstract

A user equipment (UE) selects or reselects a target cell of a non-terrestrial network or resumes a connection with a target cell after a satellite handover for a permanently fixed low earth orbit (LEO) cell. The target cell is a serving cell or a non-serving cell. The UE determines a cell type of the target cell. The cell type can be a LEO cell type, a geostationary earth orbit (GEO) cell type, a moving cell type, a fixed cell type, a temporarily fixed LEO cell type, or a permanently fixed LEO cell type. The UE completes the selection or reselection of the target cell or completes the connection with the target cell based on the cell type.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Patent Application No. 17 / 475,140, ​​filed September 14, 2021, entitled “CELL TYPE SELECTION FOR NON-TERRESTRIAL NETWORKS,” which claims the benefit of U.S. Provisional Patent Application No. 63 / 078,872, filed September 15, 2020, entitled “CELL TYPE SELECTION FOR NON-TERRESTRIAL NETWORKS,” the disclosure of which is expressly incorporated herein by reference in its entirety. Technical Field

[0003] Various aspects of this disclosure generally relate to wireless communications, and more specifically, various aspects of this disclosure relate to techniques and apparatus for selecting between a first cell type (such as a low Earth orbit (LEO) cell type) and a second cell type (such as a geostationary orbit (GEO) cell type) in a non-terrestrial network (NTN). Background Technology

[0004] Wireless communication systems are widely deployed to provide a variety of telecommunications services such as telephone, video, data, messaging, and broadcasting. Typical wireless communication systems employ multiple access technologies that can support communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc.). Examples of such multiple access technologies include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, Single Carrier Frequency Division Multiple Access (SC-FDMA) systems, Time Division Synchronous Code Division Multiple Access (TD-SCDMA) systems, and Long Term Evolution (LTE). LTE / improved LTE is a collection of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard issued by the 3rd Generation Partnership Project (3GPP).

[0005] A wireless communication network may include multiple base stations (BSs) capable of supporting communication for multiple user equipments (UEs). UEs can communicate with base stations (BSs) via downlinks and uplinks. A downlink (or forward link) refers to the communication link from the BS to the UE, and an uplink (or reverse link) refers to the communication link from the UE to the BS. As will be described in more detail, a BS may be referred to as a Node B, Evolved Node B (eNB), gNB, Access Point (AP), Radio Headend, Transmit and Receive Point (TRP), New Radio (NR) BS, 5G Node B, etc.

[0006] The multiple access technologies mentioned above have been adopted by various telecommunications standards to provide a common protocol that enables different user equipment to communicate at the city, national, regional, and even global levels. New Radio (NR) (also known as 5G) is a collection of enhancements to the LTE mobile standard issued by the 3rd Generation Partnership Project (3GPP). NR is designed to better integrate with other open standards by improving spectrum efficiency, reducing costs, improving service, utilizing new spectrum, and using Orthogonal Frequency Division Multiplexing (OFDM) with a Cyclic Prefix (CP) on the downlink (DL) and CP-OFDM and / or SC-FDM (e.g., also known as Discrete Fourier Transform Extended OFDM (DFT-s-OFDM)) on the uplink (UL), and to better support mobile broadband network access by supporting beamforming, multiple-input multiple-output (MIMO) antenna technologies, and carrier aggregation. Summary of the Invention

[0007] According to various aspects of this disclosure, a wireless communication method selects or reselects a target cell of a non-terrestrial network or restores a connection with the target cell. The target cell is a serving cell or a non-serving cell. The UE determines the cell type of the target cell. The cell type may be a low Earth orbit (LEO) cell type, a geostationary orbit (GEO) cell type, a mobile cell type, a fixed cell type, a temporarily fixed LEO cell type, or a permanently fixed LEO cell type. The UE further performs the selection or reselection of the target cell or the restoration of the connection with the target cell based on the cell type.

[0008] In other aspects of this disclosure, an apparatus for wireless communication at a user equipment (UE) includes a processor and a memory coupled to the processor. Instructions stored in the memory, when executed by the processor, are operable to cause the apparatus to select or reselect a target cell of a non-terrestrial network or to restore a connection with the target cell. The target cell is a serving cell or a non-serving cell. The apparatus can determine the cell type of the target cell. The cell type can be a low Earth orbit (LEO) cell type, a geostationary orbit (GEO) cell type, a mobile cell type, a fixed cell type, a temporarily fixed LEO cell type, or a permanently fixed LEO cell type. The apparatus can also perform the selection or reselection of the target cell or the restoration of the connection with the target cell based on the cell type.

[0009] In other aspects of this disclosure, a user equipment (UE) for wireless communication includes: a unit for selecting or reselecting a target cell of a non-terrestrial network or restoring a connection with the target cell, the target cell being either a serving cell or a non-serving cell. The UE includes: a unit for determining the cell type of the target cell. The cell type may be a low Earth orbit (LEO) cell type, a geostationary orbit (GEO) cell type, a mobile cell type, a fixed cell type, a temporarily fixed LEO cell type, or a permanently fixed LEO cell type. The UE further includes: a unit for selecting or reselecting the target cell or restoring the connection with the target cell based on the cell type.

[0010] In other aspects of this disclosure, a non-transitory computer-readable medium having program code recorded thereon is disclosed. The program code is executed by a user equipment (UE) and includes program code for selecting or reselecting a target cell of a non-terrestrial network or restoring a connection to the target cell, the target cell being either a serving cell or a non-serving cell. The UE includes program code for determining the cell type of the target cell. The cell type includes low Earth orbit (LEO) cell type, geostationary orbit (GEO) cell type, mobile cell type, fixed cell type, temporarily fixed LEO cell type, or permanently fixed LEO cell type. The UE also includes program code for performing the selection or reselection of the target cell or restoring the connection to the target cell based on the cell type.

[0011] The aspects generally include, as described substantially with reference to the accompanying drawings and description, and as shown by reference to the accompanying drawings and description, methods, apparatus, systems, computer program products, non-transitory computer-readable media, user equipment, base stations, wireless communication equipment, and processing systems.

[0012] The features and technical advantages of the examples have been outlined rather broadly above in accordance with this disclosure to facilitate a better understanding of the specific embodiments described thereafter. Further features and advantages will be described. For the same purposes of this disclosure, the disclosed concepts and specific examples can be readily utilized as a basis for modifications or the design of other structures. Such equivalent constructions do not depart from the scope of the appended claims. The characteristics of the disclosed concepts (both in their organization and operation) and their associated advantages will be better understood, together with the following description, when considered in conjunction with the accompanying drawings. Each drawing in the drawings is provided for illustrative and descriptive purposes and is not intended to limit the scope of the claims. Attached Figure Description

[0013] To gain a detailed understanding of the features of this disclosure, reference can be made to various aspects, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only certain aspects of this disclosure and are therefore not intended to limit its scope, as the specification may acknowledge other equally valid aspects. The same reference numerals in different drawings may identify the same or similar elements.

[0014] Figure 1 This is a block diagram that conceptually illustrates an example of a wireless communication network according to various aspects of this disclosure.

[0015] Figure 2 This is a block diagram conceptually illustrating an example of a base station communicating with a user equipment (UE) in a wireless communication network according to various aspects of this disclosure.

[0016] Figure 3 This is a schematic diagram illustrating an example of a wireless communication system that supports cell type selection for non-terrestrial networks according to various aspects of this disclosure.

[0017] Figure 4 This is a schematic diagram illustrating alternative network configurations for wireless communication systems supporting cell type selection for non-terrestrial networks, based on various aspects of this disclosure.

[0018] Figure 5 This is a schematic diagram illustrating a network configuration of a wireless communication system that supports cell type selection for non-terrestrial networks, according to various aspects of this disclosure.

[0019] Figure 6 This is a call flow diagram illustrating the selection of cell type for non-terrestrial networks according to various aspects of this disclosure.

[0020] Figure 7 This is a flowchart illustrating an example process performed by a user equipment (UE) according to various aspects of this disclosure. Detailed Implementation

[0021] Wireless communication systems can include non-terrestrial networks with base stations that use satellites to relay communications to user equipment (UEs). In other scenarios, satellites can operate as base stations. For example, satellites can be low Earth orbit (LEO) satellites, geostationary orbit (GEO) satellites, high altitude platform stations (HAPS) or medium Earth orbit (MEO) satellites. Other cell types include mobile cells or fixed cells, as well as terrestrial network cells. UEs may have preferences or restrictions regarding which cell type to select. The described techniques relate to UE cell selection for specific cell types in non-terrestrial networks.

[0022] The various aspects of this disclosure are first described in the context of a wireless communication system. The various aspects of this disclosure are also illustrated and described with reference to process flows. Furthermore, the various aspects of this disclosure are illustrated and described with reference to apparatus diagrams, system diagrams, and flowcharts relating to cell type selection for non-terrestrial networks.

[0023] Figure 1 Examples of a non-terrestrial wireless communication system 100 supporting cell type selection according to various aspects of this disclosure are shown. The wireless communication system 100 includes a base station 105, a user equipment (UE) 115, a satellite 140, and a core network 130. In some examples, the wireless communication system 100 may be a Long Term Evolution (LTE) network, an improved LTE (LTE-A) network, an LTE-A Pro network, or a New Radio (NR) network. In some cases, the wireless communication system 100 may support enhanced broadband communication, ultra-reliable (e.g., mission-critical) communication, low-latency communication, or communication with low-cost and low-complexity devices.

[0024] Base station 105 can wirelessly communicate with UE 115 via one or more base station antennas. Base station 105 may include, or may be referred to by those skilled in the art as, a base transceiver, wireless base station, access point, wireless transceiver, Node B, eNode B (eNB), next-generation Node B or giga-Node B (any of which may be referred to as gNB), home Node B, home eNode B, or some other suitable term. Wireless communication system 100 may include different types of base stations 105 (e.g., macro base stations or small cell base stations). The described UE 115 may be able to communicate with various types of base stations 105 and network equipment including macro eNBs, small cell eNBs, gNBs, relay base stations, etc.

[0025] Each base station 105 may be associated with a specific geographic coverage area 110, within which communication with each UE 115 is supported. Each base station 105 may provide communication coverage to its respective geographic coverage area 110 via a communication link 125, and the communication link 125 between the base station 105 and the UE 115 may utilize one or more carriers. The communication link 125 shown in the wireless communication system 100 may include uplink streaming from the UE 115 to the base station 105 or downlink streaming from the base station 105 to the UE 115. Downlink streaming may also be referred to as downlink streaming or forward link streaming, while uplink streaming may also be referred to as uplink streaming or reverse link streaming.

[0026] The geographic coverage area 110 for base station 105 can be divided into sectors that constitute a part of the geographic coverage area 110, and each sector can be associated with a cell. For example, each base station 105 can provide communication coverage for macro cells, small cells, hotspots, or other types of cells, or various combinations thereof. In some examples, base station 105 can be mobile and thus provide communication coverage for mobile geographic coverage areas 110. In some examples, different geographic coverage areas 110 associated with different technologies can overlap, and overlapping geographic coverage areas 110 associated with different technologies can be supported by the same base station 105 or by different base stations 105. For example, wireless communication system 100 can include heterogeneous LTE / LTE-A / LTE-A Pro or NR networks, in which different types of base stations 105 provide coverage for various geographic coverage areas 110.

[0027] The term "cell" refers to a logical communication entity used for communication with base station 105 or a satellite beam (e.g., via a carrier), and can be associated with an identifier (e.g., a Physical Cell Identifier (PCID) or Virtual Cell Identifier (VCID)) used to distinguish neighboring cells operating via the same or different carriers. A cell can be, for example, a mobile cell relative to a satellite beam, a temporarily fixed cell, or a permanently fixed cell. In some examples, a carrier can support multiple cells, and different cells can be configured according to different protocol types that can provide access for different types of devices (e.g., Machine-Type Communication (MTC), Narrowband Internet of Things (NB-IoT), Enhanced Mobile Broadband (eMBB), etc.). In some cases, the term "cell" can refer to a portion of a geographic coverage area 110 (e.g., a sector) over which the logical entity operates.

[0028] UE 115 may be distributed throughout the wireless communication system 100, and each UE 115 may be stationary or mobile. UE 115 may also be referred to as a mobile device, wireless device, remote device, handheld device, or user equipment, or any other suitable term, wherein "device" may also be referred to as a unit, station, terminal, or client. UE 115 may also be a personal electronic device, such as a cellular phone, personal digital assistant (PDA), tablet computer, laptop computer, or personal computer. In some examples, UE 115 may also refer to a wireless local loop (WLL) station, Internet of Things (IoT) device, Internet of Everything (IoE) device, or MTC device, which may be implemented in various items such as home appliances, vehicles, and meters.

[0029] For example, some UEs 115 for MTC or IoT devices can be low-cost or low-complexity devices, and can provide automated communication between machines (e.g., via machine-to-machine (M2M) communication). M2M communication or MTC can refer to data communication technologies that allow devices to communicate with each other or with base station 105 without human intervention. In some examples, M2M communication or MTC may include communication from devices integrating sensors or meters to measure or capture information and relay that information to a central server or application, which can then utilize the information or present it to personnel interacting with the program or application. Some UEs 115 can be designed to collect information or automate machine behavior. Examples of applications for MTC devices include: smart metering, inventory monitoring, water level monitoring, equipment monitoring, healthcare monitoring, wildlife monitoring, weather and geological event monitoring, fleet management and tracking, remote security sensing, physical access control, and transaction-based billing.

[0030] Some UEs 115 can be configured to operate in a power-saving mode, such as half-duplex communication (e.g., a mode that supports unidirectional communication via transmit or receive but not simultaneous transmit and receive). In some examples, half-duplex communication can be performed at a reduced peak rate. Other power-saving techniques for UE 115 include entering a power-saving "deep sleep" mode when not engaged in active communication, or (e.g., operating on limited bandwidth, depending on narrowband communication). In some cases, UE 115 can be designed to support critical functions (e.g., mission-critical functions), and the wireless communication system 100 can be configured to provide highly reliable communication for these functions.

[0031] In some cases, UE 115 may also be able to communicate directly with other UE 115 (e.g., using peer-to-peer (P2P) or device-to-device (D2D) protocols). One or more UEs in a group of UEs 115 utilizing D2D communication may be within the geographic coverage area 110 of base station 105. Other UEs 115 in such a group may be outside the geographic coverage area 110 of base station 105, or may not be able to receive transmissions from base station 105 in other ways. In some cases, several groups of UEs 115 communicating via D2D communication may utilize a one-to-many (1:M) system, in which each UE 115 sends to each other UE 115 in the group. In some cases, base station 105 facilitates the scheduling of resources for D2D communication. In other cases, D2D communication is performed between UEs 115 without involving base station 105.

[0032] Base station 105 can communicate with core network 130 and communicate with each other. For example, base station 105 can be connected to core network 130 via backhaul link 132 (e.g., via S1, N2, N3 or other interfaces). Base station 105 can communicate with each other directly (e.g., directly between base stations 105) or indirectly (e.g., via core network 130) via backhaul link 134 (e.g., via X2, Xn or other interfaces).

[0033] Core network 130 can provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. Core network 130 can be an evolved packet core (EPC), which may include at least one mobility management entity (MME), at least one serving gateway (S-GW), and at least one packet data network (PDN) gateway (P-GW). The MME can manage non-access stratum (e.g., control plane) functions, such as mobility, authentication, and bearer management for UE 115 served by base station 105 associated with the EPC. User IP packets may be transmitted via the S-GW, which itself may be connected to the P-GW. The P-GW can provide IP address allocation and other functions. The P-GW may be connected to the network operator's IP services. The operator's IP services may include access to the Internet, intranets, IP Multimedia Subsystem (IMS), or packet-switched (PS) streaming services.

[0034] At least some of the network devices (such as base station 105) may include sub-components of, for example, access network entities, which may be examples of access node controllers (ANCs). Each access network entity may communicate with UE 115 through multiple other access network transport entities (which may be referred to as radio headends, smart radio headends, or transmit / receive points (TRPs)). In some configurations, the various functions of each access network entity or base station 105 may be distributed across various network devices (e.g., radio headends and access network controllers) or incorporated into a single network device (e.g., base station 105).

[0035] Wireless communication system 100 can operate using one or more frequency bands (typically in the range of 300 MHz to 300 GHz). The region from 300 MHz to 3 GHz is generally referred to as the ultra-high frequency (UHF) region or decimeter band because the wavelength range is approximately one decimeter to one meter in length. UHF waves may be blocked or deflected by buildings and environmental features. However, these waves can penetrate structures designed for macrocells sufficiently to provide service to UE 115 located indoors. Transmission of UHF waves can be associated with smaller antennas and shorter distances (e.g., less than 100 km) compared to transmission using smaller frequencies and longer wavelengths in the high frequency (HF) or very high frequency (VHF) portions of the spectrum below 300 MHz.

[0036] The wireless communication system 100 can also operate in the ultra-high frequency (SHF) region using a frequency band from 3 GHz to 30 GHz (also known as the centimeter band). The SHF region includes frequency bands such as the 5 GHz Industrial, Scientific and Medical (ISM) band, which can be used as needed by devices that can tolerate interference from other users.

[0037] The wireless communication system 100 can also operate in the extremely high frequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz) (also referred to as the millimeter band). In some examples, the wireless communication system 100 can support millimeter-wave (mmWave) communication between the UE 115 and the base station 105, and the EHF antennas of the respective devices may be even smaller and more compact than UHF antennas. In some cases, this can facilitate the use of antenna arrays within the UE 115. However, propagation of EHF transmissions may suffer from even greater atmospheric attenuation and shorter distances than SHF or UHF transmissions. The disclosed techniques can be employed across transmissions using one or more different frequency regions, and the designated use of frequency bands across these frequency regions may vary due to national or regulatory factors.

[0038] In some cases, wireless communication system 100 may utilize both licensed and unlicensed radio frequency spectrum bands. For example, wireless communication system 100 may employ licensed assisted access (LAA), unlicensed LTE (LTE-U) radio access technology, or NR technology in an unlicensed band, such as the 5 GHz ISM band. When operating in an unlicensed radio frequency spectrum band, wireless devices such as base station 105 and UE 115 may employ a listen-before-talk (LBT) procedure to ensure that the frequency channel is idle before transmitting data. In some cases, operation in an unlicensed band may be based on a CA configuration that cooperates with CC operations in a licensed band (e.g., LAA). Operation in the unlicensed spectrum may include downlink streaming, uplink streaming, peer-to-peer transmission, or a combination thereof. Duplexing in the unlicensed spectrum may be based on frequency division duplex (FDD), time division duplex (TDD), or a combination of both.

[0039] In some examples, base station 105 or UE 115 may be equipped with multiple antennas, which can be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communication, or beamforming. For example, wireless communication system 100 may use a transmission scheme between a transmitting device (e.g., base station 105) and a receiving device (e.g., UE 115), wherein the transmitting device is equipped with multiple antennas, and the receiving device is equipped with one or more antennas. MIMO communication can employ multipath signal propagation to increase spectral efficiency by transmitting or receiving multiple signals via different spatial layers, which can be referred to as spatial multiplexing. For example, multiple signals may be transmitted by the transmitting device via different antennas or different combinations of antennas. Similarly, the multiple signals may be received by the receiving device via different antennas or different combinations of antennas. Each of the multiple signals may be referred to as a separate spatial stream and may carry bits associated with the same data stream (e.g., the same codeword) or different data streams. Different spatial layers may be associated with different antenna ports used for channel measurement and reporting. MIMO technology includes single-user MIMO (SU-MIMO) and multi-user MIMO (MU-MIMO). In SU-MIMO, multiple spatial streams are sent to the same receiving device, while in MU-MIMO, multiple spatial streams are sent to multiple devices.

[0040] Beamforming (also known as spatial filtering, directional transmission, or directional reception) is a signal processing technique that can be used at a transmitting or receiving device (e.g., base station 105 or UE 115) to shape or guide an antenna beam (e.g., a transmit beam or a receive beam) along a spatial path between the transmitting and receiving devices. Beamforming can be achieved by combining signals transmitted via antenna elements of an antenna array, such that signals propagating in a specific direction relative to the antenna array experience constructive interference, while other signals experience destructive interference. Adjustments to the signals transmitted via the antenna elements can include the transmitting or receiving device applying a certain amplitude and phase shift to the signal carried by each of the antenna elements associated with that device. The adjustments associated with each antenna element can be specified by a beamforming weight set associated with a specific direction (e.g., relative to the antenna array of the transmitting or receiving device, or relative to some other orientation).

[0041] In one example, base station 105 may use multiple antennas or antenna arrays to perform beamforming operations for directional communication with UE 115. For example, some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) may be transmitted multiple times by base station 105 in different directions, which may include transmitting signals according to different beamforming weight sets associated with different transmission directions. (e.g., by base station 105 or a receiving device such as UE 115) the transmission in different beam directions can be used to identify the beam direction for subsequent transmissions and / or receptions by base station 105. Some signals (e.g., data signals associated with a particular receiving device) may be transmitted by base station 105 in a single beam direction (e.g., the direction associated with, for example, the receiving device of UE 115). In some examples, the beam direction associated with transmission along a single beam direction may be determined at least in part based on the signals transmitted in different beam directions. For example, UE 115 may receive one or more signals transmitted by base station 105 in different directions, and UE 115 may report to base station 105 an indication of the signal it received with the highest signal quality, or also report an acceptable signal quality. Although these techniques are described with reference to signals transmitted by base station 105 in one or more directions, UE 115 may employ similar techniques to transmit signals multiple times in different directions (e.g., to identify the beam direction for subsequent transmissions or receptions by UE 115), or to transmit signals in a single direction (e.g., to transmit data to a receiving device).

[0042] When a receiving device (e.g., UE 115, which may be an example of a millimeter-wave receiving device) receives various signals (such as synchronization signals, reference signals, beam selection signals, or other control signals) from base station 105, it may attempt multiple receiving beams. For example, the receiving device may attempt multiple receiving directions by: receiving via different antenna subarrays; processing signals received according to different antenna subarrays; receiving according to different sets of receiving beamforming weights applied to signals received at multiple antenna elements of the antenna array; or processing received signals according to different sets of receiving beamforming weights applied to signals received at multiple antenna elements of the antenna array, any of which may be referred to as "listening" according to different receiving beams or receiving directions. In some examples, the receiving device may use a single receiving beam to receive along a single beam direction (e.g., when receiving data signals). This single receiving beam may be aligned at least partially based on beam directions determined by listening to different receiving beam directions (e.g., determining the beam direction with the highest signal strength, highest signal-to-noise ratio, or other acceptable signal quality based at least partially based on listening to multiple beam directions).

[0043] In some cases, the antennas of base station 105 or UE 115 may be located within one or more antenna arrays that support MIMO operation or transmit / receive beamforming. For example, one or more base station antennas or antenna arrays may coexist on antenna components, such as those of an antenna tower. In some cases, the antennas or antenna arrays associated with base station 105 may be located in different geographical locations. Base station 105 may have an antenna array containing multiple rows and columns of antenna ports that base station 105 can use to support beamforming for communications with UE 115. Similarly, UE 115 may have one or more antenna arrays that can support various MIMO or beamforming operations.

[0044] In some cases, the wireless communication system 100 may be a packet-based network operating according to a layered protocol stack. In the user plane, communication at the bearer or Packet Data Convergence Protocol (PDCP) layer may be IP-based. In some cases, the Radio Link Control (RLC) layer may perform packet segmentation and reassembly for communication over logical channels. The Media Access Control (MAC) layer may perform priority processing and multiplexing of logical channels to transport channels. The MAC layer may also use Hybrid Automatic Repeat Request (HARQ) to provide retransmissions at the MAC layer to improve link efficiency. In the control plane, the Radio Resource Control (RRC) protocol layer may provide the establishment, configuration, and maintenance of RRC connections between the UE 115 and the base station 105 or the core network 130 supporting radio bearers for user plane data. At the physical (PHY) layer, transport channels may be mapped to physical channels.

[0045] In some cases, UE 115 and base station 105 may support data retransmission to increase the likelihood of successfully receiving data. HARQ feedback is a technique to increase the likelihood of correctly receiving data through communication link 125. HARQ may include a combination of error correction (e.g., using Cyclic Redundancy Check (CRC)), forward error correction (FEC), and retransmission (e.g., Automatic Repeat Request (ARQ)). HARQ can improve throughput at the MAC layer under poor radio conditions (e.g., signal-to-noise ratio conditions). In some cases, the radio device may support same-slot HARQ feedback, where the device can provide HARQ feedback in a specific time slot for data received in a previous symbol within the time slot. In other cases, the device can provide HARQ feedback in subsequent time slots or according to some other time interval.

[0046] The time interval in LTE or NR can be expressed as a multiple of the basic time unit (e.g., it could refer to T). s = 1 / 30,720,000 seconds of sampling period). The time interval of communication resources can be organized according to radio frames, each radio frame having a duration of 10 milliseconds (ms), where the frame period can be expressed as T. f =307,200T sThe radio frames can be identified by a System Frame Number (SFN) ranging from 0 to 1023. Each frame may include 10 subframes numbered from 0 to 9, and each subframe may have a duration of 1 ms. (For example, depending on the length of the cyclic prefix (CP) from the prefix to each symbol period) A subframe may be further divided into two time slots, each time slot having a duration of 0.5 ms, and each time slot may contain 6 or 7 modulation symbol periods. Excluding the cyclic prefix, each symbol period may contain 2048 sampling periods. In some cases, a subframe may be the minimum scheduling unit of the wireless communication system 100, and may be referred to as a Transmission Time Interval (TTI). In other cases, the minimum scheduling unit of the wireless communication system 100 may be shorter than a subframe, or may be dynamically selected (e.g., in a burst of shortened TTI (sTTI), or in a component carrier using a selected sTTI).

[0047] In some wireless communication systems, time slots can be further divided into multiple micro-time slots containing one or more symbols. In some instances, a symbol or micro-time slot can be the smallest unit of scheduling. For example, each symbol can vary in duration depending on the subcarrier spacing or the frequency band of operation. Furthermore, some wireless communication systems can implement time slot aggregation, in which multiple time slots or micro-time slots are aggregated together for communication between UE 115 and base station 105.

[0048] The term "carrier" refers to a set of radio frequency spectrum resources with a defined physical layer structure used to support communication over communication link 125. For example, a carrier of communication link 125 may include a portion of a radio frequency spectrum band operating according to a physical layer channel for a given radio access technology. Each physical layer channel may carry user data, control information, or other signaling. A carrier may be associated with a predefined frequency channel (e.g., an E-UTRA absolute radio frequency channel number (EARFCN)) and may be located according to a channel raster used for discovery by UE 115. A carrier may be a downlink or uplink stream (e.g., in FDD mode), or may be configured to carry both downlink and uplink communication (e.g., in TDD mode). In some examples, the signal waveform transmitted via a carrier may consist of multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques such as OFDM or DFT-s-OFDM).

[0049] The carrier organization structure can vary depending on the radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR, etc.). For example, communication over a carrier can be organized according to a Time Interval (TTI) or time slot, each of which may include user data and control information or signaling for supporting the decoding of that user data. A carrier may also include dedicated acquisition signaling (e.g., synchronization signals or system information) and control signaling coordinating operations on the carrier. In some examples (e.g., in a carrier aggregation configuration), a carrier may also have acquisition signaling or control signaling coordinating operations on other carriers.

[0050] Physical channels can be multiplexed on carriers using various techniques. For example, physical control channels and physical data channels can be multiplexed on downlink stream carriers using time division multiplexing (TDM), frequency division multiplexing (FDM), or a hybrid TDM-FDM technique. In some examples, control information transmitted in the physical control channel can be distributed in a cascaded manner between different control regions (e.g., between a common control region or common search space and one or more UE-specific control regions or UE-specific search spaces).

[0051] A carrier can be associated with a specific bandwidth of the radio frequency spectrum, and in some examples, the carrier bandwidth can be referred to as the carrier or the “system bandwidth” of the wireless communication system 100. For example, the carrier bandwidth can be one of a plurality of predetermined bandwidths for a particular wireless access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 MHz). In some examples, each serving UE 115 can be configured to operate over a portion or all of the carrier bandwidth. In other examples, some UEs 115 can be configured to operate using a narrowband protocol type associated with a predetermined portion or range within the carrier (e.g., a set of subcarriers or RBs) (e.g., an “in-band” deployment of the narrowband protocol type).

[0052] In a system employing MCM technology, a resource element may include a symbol period (e.g., the duration of a modulation symbol) and a subcarrier, wherein the symbol period and subcarrier spacing are inversely related. The number of bits carried by each resource element can depend on the modulation scheme (e.g., the order of the modulation scheme). Therefore, the more resource elements UE 115 receives and the higher the order of the modulation scheme, the higher the data rate that UE 115 can use. In a MIMO system, wireless communication resources can refer to a combination of radio frequency spectrum resources, temporal resources, and spatial resources (e.g., spatial layers), and the use of multiple spatial layers can further increase the data rate used for communication with UE 115.

[0053] The devices of the wireless communication system 100 (e.g., base station 105 or UE 115) may have a hardware configuration that supports communication over a specific carrier bandwidth, or may be configurable to support communication over one carrier bandwidth in a set of carrier bandwidths. In some examples, the wireless communication system 100 may include base station 105 and / or UE 115 that can support simultaneous communication via carriers associated with more than one different carrier bandwidth.

[0054] The wireless communication system 100 can support communication with the UE 115 on multiple cells or carriers, a feature that may be referred to as carrier aggregation (CA) or multi-carrier operation. Depending on the carrier aggregation configuration, the UE 115 can be configured to have multiple downlink flow CCs and one or more uplink flow CCs. Carrier aggregation can be used in conjunction with both FDD component carriers and TDD component carriers.

[0055] In some cases, the wireless communication system 100 may utilize enhanced component carrier (eCC). eCC can be characterized by one or more features including: a wider carrier or frequency channel bandwidth, a shorter symbol duration, a shorter TTI duration, or a modified control channel configuration. In some cases (e.g., when multiple serving cells have suboptimal or non-ideal backhaul links), eCC may be associated with carrier aggregation or dual connectivity configurations. eCC can also be configured for use in unlicensed or shared spectrum (e.g., where more than one operator is permitted to use the spectrum). eCC characterized by a wide carrier bandwidth may include one or more segments that can be utilized by a UE 115 that is unable to monitor the entire carrier bandwidth or is otherwise configured to use a limited carrier bandwidth (e.g., to save power).

[0056] In some cases, eCC can utilize a different symbol duration than other CCs, which may include the use of a reduced symbol duration compared to the symbol durations of other CCs. A shorter symbol duration can be associated with increased spacing between adjacent subcarriers. Devices utilizing eCC (such as UE 115 or base station 105) can transmit wideband signals with a reduced symbol duration (e.g., 16.67 microseconds), depending on the frequency channel or carrier bandwidth of 20MHz, 40MHz, 60MHz, 80MHz, etc. The TTI in eCC can include one or more symbol periods. In some cases, the TTI duration (i.e., the number of symbol periods in the TTI) can be variable.

[0057] For example, NR wireless communication systems can utilize licensed, shared, and unlicensed spectrum bands, as well as any combination of other spectrum bands. The flexibility in eCC symbol duration and subcarrier spacing allows for the use of eCC across multiple spectrums. In some examples, NR shared spectrum can increase spectrum utilization and spectral efficiency, particularly through dynamic vertical (e.g., across the frequency domain) and horizontal (e.g., across the time domain) sharing of resources.

[0058] In some examples, the wireless communication system 100 may be or be associated with a terrestrial network. Examples of terrestrial networks may include an NR system, for example, including base station 105 and UE 115. Within the NR system, uplink streaming (e.g., CP-OFDM or DFT-S-OFDM waveforms) can arrive at base station 105 from UE 115 within an interval (e.g., during the CP duration). For a subcarrier spacing of 120 kHz, the CP duration might be approximately 0.59 μs. Alternatively, the subcarrier spacing for mm-wave communication within the Ka band (such as downlink streaming between approximately 20 GHz and 30 GHz) can be larger compared to the uplink streaming. For example, a subcarrier spacing greater than 120 kHz can improve communication reliability due to frequency errors caused by Doppler. In this example, a subcarrier spacing greater than 120 kHz could result in a CP duration of 0.25 μs.

[0059] In some examples, additionally or alternatively, the wireless communication system 100 may be a non-terrestrial network or associated with it. For example, base station 105 may utilize satellite 140 to relay communications to UE 115. Due to the mobility of satellite 140 and the distance from satellite 140 to UE 115, communications may experience uplink timing errors (e.g., downlink timing tracking errors and / or variations in propagation delays). For example, satellite 140 may be a non-geostationary satellite that can orbit UE 115 from 600 km and travel at a speed of approximately 7.6 km / s. Therefore, the round-trip time (e.g., update rate) between satellite 140 and UE 115 can vary by up to 50 μs per second.

[0060] For example, assuming the uplink timing is ideal at time t (e.g., no timing adjustment is applied to time t), after approximately 10 ms, the uplink timing error might be approximately 0.5 μs. Therefore, the round-trip time for satellite 140 might be approximately 30 ms, and the timing advance command calculated based on the uplink transmission at time t could be turned off by 1.5 μs when it reaches UE 115. To compensate for the uplink timing error, base station 105 (also referred to as a "gateway") can provide UE 115 with a timing command for uplink transmission. UE 115 can receive the timing command and use the timing adjustment indicated in the timing command to send the uplink transmission to base station 105.

[0061] UE 115 may include a cell type selection module 150. For simplicity, only one UE 115 is shown as including the cell type selection module 150. The cell type selection module 150 can select or reselect a target cell for a non-terrestrial network or restore connectivity to a target cell. The target cell may be a serving cell or a non-serving cell. The cell type selection module 150 can also determine the cell type of the target cell. The selection module can also perform the selection or reselection of the target cell based on the cell type.

[0062] Figure 2 Base station 105 and UE 115 are shown (which may be...) Figure 1 The block diagram of design 200 (a base station 105 and a UE 115) is shown. The base station 105 may be equipped with T antennas 234a to 234t, and the UE 115 may be equipped with R antennas 252a to 252r, wherein generally, T≥1 and R≥1.

[0063] At base station 105, transmit processor 220 can receive data for one or more UEs from data source 212, select one or more modulation and coding schemes (MCS) for each UE based at least in part on channel quality indicators (CQI) received from the UE, process (e.g., code and modulate) the data for each UE based at least in part on the MCS selected for the UE, and provide data symbols for all UEs. Transmit processor 220 can also process system information (e.g., resource allocation information for semi-static (SRPI) and other information) and control information (e.g., CQI requests, permission, upper-layer signaling, etc.), and provide overhead symbols and control symbols. Transmit processor 220 can also generate reference symbols for reference signals (e.g., cell-specific reference signals (CRS)) and synchronization signals (e.g., primary synchronization signal (PSS) and secondary synchronization signal (SSS)). Where applicable, the transmit (TX) multiple-input multiple-output (MIMO) processor 230 can perform spatial processing (e.g., precoding) on ​​data symbols, control symbols, overhead symbols, and / or reference symbols, and can provide T output symbol streams to T modulators (MODs) 232a to 232t. Each modulator 232 can process its own output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator 232 can further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. The T downlink signals from modulators 232a to 232t can be transmitted respectively via T antennas 234a to 234t. According to the aspects described in more detail below, the synchronization signal can be generated using position coding to convey additional information.

[0064] At UE 115, antennas 252a to 252r can receive downlink signals from base station 105 and / or other base stations, and can provide the received signals to demodulators (DEMODs) 254a to 254r respectively. Each demodulator 254 can adjust (e.g., filter, amplify, down-convert, and digitize) the received signal to obtain an input sample. Each demodulator 254 can further process the input sample (e.g., for OFDM, etc.) to obtain the received symbols. MIMO detector 256 can obtain the received symbols from all R demodulators 254a to 254r, perform MIMO detection on the received symbols (if applicable), and provide the detected symbols. Receiver processor 258 can process (e.g., demodulate and decode) the detected symbols, provide the decoded data for UE 115 to data sink 260, and provide the decoded control information and system information to controller / processor 280. The channel processor can determine the Received Reference Signal Power (RSRP), Received Signal Strength Indicator (RSSI), Received Reference Signal Quality (RSRQ), Channel Quality Indicator (CQI), etc. In some aspects, one or more components in UE 115 may be included in a housing.

[0065] On the uplink, at UE 115, transmit processor 264 can receive and process data from data source 262, as well as control information from controller / processor 280 (e.g., for reports including RSRP, RSSI, RSRQ, CQI, etc.). Transmit processor 264 can also generate reference symbols for one or more reference signals. Symbols from transmit processor 264 can be pre-encoded (if applicable) by TX MIMO processor 266, further processed by modulators 254a to 254r (e.g., for DFT-s-OFDM, CP-OFDM, etc.), and transmitted to base station 105. At base station 105, uplink signals from UE 115 and other UEs can be received by antenna 234, processed by demodulator 232, detected by MIMO detector 236 (if applicable), and further processed by receive processor 238 to obtain decoded data and control information transmitted by UE 115. The receiving processor 238 can provide decoded data to the data sink 239 and decoded control information to the controller / processor 240. The base station 105 may include a communication unit 244 and transmit data to the core network 130 via the communication unit 244. The core network 130 may include a communication unit 294, a controller / processor 290, and a memory 292.

[0066] UE 115 controller / processor 280 and / or Figure 2Any other components may perform one or more technologies associated with cell type selection, as described in more detail elsewhere herein. For example, the UE may be a smart UE or an NR UE capable of processing eMBB data and voice. The controller / processor 280 of UE 115 and / or Figure 2 Any other component can perform or direct, for example Figure 6 and Figure 7 The method and / or other processes as described. Memory 242 and memory 282 can store data and program code for base station 105 and UE 115, respectively. Scheduler 246 can schedule UE for data transmission on downlink and / or uplink.

[0067] In some aspects, UE 115 may include units for selection, reselection, or recovery; units for determination; units for completion; units for acquisition; units for reception; units for mapping; units for prohibition; units for tracking; units for communication; and / or units for reporting. Such units may include combinations of... Figure 2 One or more components of the UE 115 described.

[0068] As indicated above, Figure 2 This is provided merely as an example. Other examples may differ from those provided. Figure 2 The example described.

[0069] Figure 3 This is a schematic diagram illustrating an example of a wireless communication system 300 supporting a cell type selection process for a non-terrestrial network according to various aspects of this disclosure. In some examples, the wireless communication system 300 can implement... Figure 1 The wireless communication system 100 includes various aspects. The wireless communication system 300 may include a base station 105-a, a UE 115-a, and a satellite 140-a, which may be referenced... Figure 1 Examples of corresponding devices described. For example, wireless communication system 300 may be a non-terrestrial network that may include base station 105-a, UE 115-a, and satellite 140-a. Satellite 140-a may relay communications between the base station (e.g., base station 105-a) and the mobile terminal (e.g., UE 115-a). Base station 105-a may also be referred to as a gateway. The geographical area associated with the transmission beam of satellite 140-a may be referred to as beam coverage area 330, and UE 115-a may communicate with satellite 140-a when UE 115-a is located within beam coverage area 330.

[0070] Base station 105-a can perform communication procedures (e.g., Radio Resource Control (RRC) procedures, such as cell acquisition, random access, RRC connection, or RRC configuration) with UE 115-a. Base station 105-a can be configured with multiple antennas, which can be used for directional or beamformed transmission. As part of the communication procedure, base station 105-a can establish a bidirectional communication link 310 for communicating with UE 115-a. Alternatively or additionally, as part of the communication procedure, base station 105-a can configure UE 115-a with configuration 315 (e.g., time and frequency resources, reference signal periodicity, or indication of symbols for time slots used to transmit reference signals) via RRC signaling. Although direct communication is shown, this disclosure is primarily concerned with when UE 115-a communicates with base station 105-a via satellite 140-a.

[0071] Satellite 140-a can generate satellite information (e.g., ephemeris information) associated with communication between satellite 140-a, UE 115-a, and base station 105-a. For example, satellite 140-a can determine the propagation delay associated with transmission between satellite 140-a, UE 115-a, and base station 105-a. In some cases, the propagation delay can be based on the distance d from satellite 140-a to point 305 (e.g., the center) of beam coverage area 330. In other cases, the propagation delay can be a factor of distance d, which may correspond to the round-trip distance between base station 105-a and satellite 140-a. Alternatively or additionally, the propagation delay can be an estimated round-trip delay or round-trip time between UE 115-a and base station 105-a, which may be at least partially based on distance d and / or 2d. It should be noted that distance d may not reflect the precise distance from satellite 140-a to UE 115-a. For example, UE 115-a may be located at the edge of the beam coverage area 330, and its distance from satellite 140-a may differ from distance d. However, such a distance difference may be insignificant compared to distance d. Therefore, distance d can be a sufficient representation of the distance from satellite 140-a to UE 115-a.

[0072] Satellite 140-a can transmit satellite information to base station 105-a and / or UE 115-a via wireless communication link 335, where base station 105-a and / or UE 115-a can be located within beam coverage area 330. In some cases, satellite 140-a can update satellite information and transmit it to base station 105-a and / or UE 115-a according to a pre-configured schedule (e.g., update rate). The pre-configured schedule can be based on the speed of satellite 140-a. For example, the speed of satellite 140-a may result in a maximum round-trip time variation rate of 50 μs per second. That is, for every second of movement of satellite 140-a, the round-trip time of communication between satellite 140-a and UE 115-a can vary by, for example, 50 μs. The round-trip time variation rate can also vary based on the satellite's motion (e.g., orbit). In such cases, satellite 140-a can update satellite information multiple times per second. Alternatively or concurrently, for example, as part of configuration 315, base station 105-a may transmit satellite information to UE 115-a via bidirectional communication link 310. In some cases, base station 105-a may transmit satellite information to UE 115-a based on a pre-configured schedule (e.g., the update rate of satellite 140-a).

[0073] Satellite information may also include the velocity of satellite 140-a. In some cases, the velocity of satellite 140-a may be defined or associated with the following expression: v × cos(α), where α is the angle between the velocity vector v and the range vector d. UE 115-a may use the velocity of satellite 140-a to determine the round-trip time variation rate. In some cases, UE 115-a may use the velocity of satellite 140-a to determine the round-trip time variation rate, at least in part, based on the positioning of UE 115-a relative to point 305 of beam coverage area 330. In some examples, using the velocity of satellite 140-a, the round-trip time variation rate can be defined by the following expression: -2v × cos(α) / c, where α is the angle between the velocity vector v and the range vector d, and c is the speed of light. Accordingly, if the uplink streaming is scheduled to be adjusted at time t0 with timing t... a If the transmission is initiated, the actual transmission time of UE 115-a can be t0+t. a For those scheduled at time t a For subsequent uplink stream transmissions at +Δt without new timing adjustments provided by base station 105-a, the actual transmission time of UE 115-a can be t. a +Δt×(-2v×cos(α) / c).

[0074] When UE 115-a is in Discontinuous Receive (DRX) mode and in RRC_IDLE or RRC_CONNECTED state, base station 105-a may transmit downlink control information in certain time and frequency resources (e.g., fixed symbols). Between these time and frequency resources, UE 115-a may enter a low-power state (also known as "sleep mode") to reduce power consumption and increase battery life. In RRC_IDLE or RRC_CONNECTED state, UE 115-a may wake up once every few symbols to receive downlink streaming transmissions from base station 105-a and / or satellite 140-a. The gaps allocated before and after reference signal transmissions can benefit base station 105-a by reducing or eliminating interference between UE 115-a transmissions and transmissions from another adjacent UE.

[0075] Figure 4 This is a schematic diagram illustrating an alternative network configuration of a wireless communication system 400 supporting cell type selection for non-terrestrial networks, according to various aspects of this disclosure. In this configuration, base station 105-b is located on satellite 140-b. Base station 105-b communicates with core network 130-b via wireless communication link 335. UE 115-b communicates with non-terrestrial base station 105-b via wireless communication link 335.

[0076] Figure 5 This is a schematic diagram illustrating the network configuration of a wireless communication system 500 supporting cell type selection for non-terrestrial networks, according to various aspects of this disclosure. Figure 5 The diagram illustrates two distinct satellites, 140-b and 140-c. For ease of explanation, the base station and core network are not depicted. The first satellite 140-b may be a GEO satellite with a first beam coverage area 330-b. The second satellite 140-c may be an LEO satellite with a second beam coverage area 330-c. The UE 115-b communicates with satellites 140-b and 140-c via wireless communication links 335-b and 335-c, respectively. In some aspects, the UE 115-b may have a preference for its desired cell type (e.g., LEO or GEO). In other aspects, the UE 115-b may have restrictions regarding the cell types it can choose. For example, certain cell types may have different requirements. Aspects of this disclosure relate to how a UE selects a cell type (e.g., LEO vs. GEO, or mobile vs. fixed) during a cell selection or cell reselection process in a non-terrestrial network, or how to restore connectivity when operating in a permanently fixed LEO cell type.

[0077] like Figure 5As shown, in a non-terrestrial network (NTN), a UE can be covered by multiple cells with different cell types. Although Figure 5 This description pertains to LEO and GEO cell types, but other cell types also exist. For example, cell type selection can be between terrestrial network cell types and non-terrestrial network cell types. The UE can also consider other satellite cell types, such as High Altitude Platform Station (HAPS) cell types and Medium Earth Orbit (MEO) cell types. Furthermore, the UE can select between mobile cells and fixed cells, or between temporarily fixed cells and permanently fixed cells.

[0078] In order to select between different cell types, the UE should be able to distinguish one cell from another. LEO and GEO satellites can operate in the same frequency band. Therefore, by acquiring the synchronization signal block (SSB), the UE may not be able to distinguish whether the cell type is an LEO cell or a GEO cell.

[0079] Various aspects of this disclosure relate to techniques for detecting cell types during cell selection or cell reselection. In one configuration, to detect cell types (e.g., LEO cells vs. GEO cells), LEO and GEO cells are configured to use different demodulation reference signals (DMRS) to decode the Master Information Block (MIB). In another configuration, each of the LEO and GEO cells is configured to use different scrambling codes for the Physical Broadcast Channel (PBCH). In yet another configuration, the Physical Cell ID (PCID) or System Information Block (SIB) (e.g., System Information Block, Type 1 (SIB1)) is defined to be LEO or GEO specific. In some cases, the UE can be configured to select only specific cell types, such as LEO or GEO cells. Alternatively or concurrently, the UE can be configured with different priorities for different cell types. For example, the UE may prioritize LEO cells over GEO cells, or the UE may prioritize mobile cells over fixed cells. Therefore, it may be desirable for the UE to distinguish between cell types.

[0080] Due to operational requirements in specific cell types, cell type priority may be desired. For example, because LEO satellites are at lower altitudes than GEO satellites, the UE should track the time and frequency compensation parameters (e.g., timing advance (TA) and Doppler shift parameters) of LEO satellites more closely. More frequent tracking is appropriate because LEO satellites are more likely to exhibit Doppler shift and timing advance errors.

[0081] Examples of UE requirements for operation in LEO or GEO cells may include, for example, tracking for frequency compensation and uplink (UL) timing pre-compensation to address the Doppler effect. Additionally, UE support for large cell sizes may be specified, for example, in the case of GEO cells. Therefore, UE support for new Physical Random Access Channel (PRACH) formats for GEO cells may be specified. Otherwise, the UE should select an LEO cell. Other UE requirements include, for example, support for a larger number of Hybrid Automatic Repeat Request (HARQ) processes to maintain throughput or enabling and disabling HARQ processes or different Quality of Service (QoS) requirements (e.g., support for different Service Data Adaptation Protocol (SDAP) / Packet Data Convergence Protocol (PDCP) configurations, larger PDCP drop timers, and / or larger sequence number (SN) lengths).

[0082] According to various aspects of this disclosure, a cell may broadcast information regarding UE requirements for operation in a specific cell type (such as an LEO cell or a GEO cell). For example, if a UE wants to operate in an LEO cell, the UE should support timing advance and Doppler compensation. If the UE does not meet these requirements, the UE should select another cell type.

[0083] Alternatively, a UE profile can be defined to indicate different requirements for operation in different cell types. In this example, the base station does not broadcast a list of requirements. Instead, the base station can broadcast an index representing the set of requirements. Upon reading the index, the UE identifies the requirements for operation in the cell. The UE can be pre-configured or provided with details of the requirement profile (e.g., configuration). In this option, a separate indication of the cell type (e.g., whether the cell is LEO or GEO) may not be necessary.

[0084] According to various aspects of this disclosure, a UE can determine operational requirements for a specific cell type (e.g., LEO or GEO cell) by reading the cell's SIB1 (or another SIB). In other aspects, the UE can be configured with information indicating operational requirements based on per-PCID or per-frequency. For example, PCID and / or frequency can be mapped to profile IDs or indexes. In this example, the UE can determine whether it can meet the requirements based on the PCID. If the UE cannot meet the requirements, it can block the cell and exclude it from cell reselection. Although SIB1 broadcasting is described, other SIBs (such as non-terrestrial network-specific SIBs) can carry operational requirements or profile IDs.

[0085] According to various aspects of this disclosure, the UE may also report its capabilities regarding the requirements for operation in a specific cell type. Based on the reported capabilities, the network may redirect the UE to an appropriate cell. For example, if the UE selects a GEO cell but reports that it does not meet the operational requirements for a GEO cell, the base station may redirect the UE to an LEO cell (assuming the UE has capabilities that match the operational requirements of an LEO cell).

[0086] In other aspects, for frequencies within and / or between neighboring cells (e.g., in a list of neighboring cells) or within an inter-frequency list, a cell can broadcast a requirement for operation in a specific cell type (or supported profile). Therefore, the UE is aware not only of the requirements of the serving cell but also of the operational requirements for each neighboring cell, facilitating cell reselection. The broadcast may include a mapping of cell IDs (e.g., PCIDs) or frequencies to UE requirements for operation in a specific cell. This mapping can assist the UE in cell reselection. The base station may broadcast this mapping in an SIB message.

[0087] In addition to requirements for operation in LEO and GEO cells, base stations can also indicate whether the cell type is a mobile cell, a temporarily fixed cell, or a permanently fixed cell. In some aspects, this indication can be implicitly obtained from the beam pattern configuration in the SIB message.

[0088] LEO-fixed cells can be further differentiated into LEO temporarily fixed cells or LEO permanently fixed cells. For permanently fixed cells, in the RRC_connected state, the UE may experience service interruption during satellite handover. That is, the cell ID, System Information Block (SIB) configuration, and Radio Resource Control (RRC) configuration remain unchanged, while the cell's operation switches from one satellite to another. In this case, the RRC connection may be suspended during the interruption and resumed afterward. This may be a special case of satellite handover, while the gateway and / or base station serving the UE remains unchanged. In the RRC_idle state, the UE may experience signal interruption or loss during satellite handover. In this case, paging monitoring may be suspended during the interruption and resumed afterward.

[0089] According to various aspects of this disclosure, satellite communication gaps can be configured in the UE. During these gap periods, when a cell switches from a previous satellite to a new satellite, the UE suspends uplink / downlink (UL / DL) transmissions or paging monitoring. After the gap period, the UE resumes communication with the new satellite. If the UE does not support such an operational specification, the UE may not select a permanently fixed LEO cell.

[0090] Cell stop times can be broadcast in the SIB. The cell stop time broadcast in the SIB can be used as the start point of an interruption. It can also indicate the duration of the interruption.

[0091] Figure 6 This is a call flowchart illustrating cell type selection for a non-terrestrial network according to various aspects of this disclosure. At time t1, UE 610 receives an instruction from satellite 620 of a first cell type. In this example, the first cell type is an LEO cell type. UE 610 also receives a request for operation in the LEO cell type. At time t2, UE 610 receives an instruction from satellite 630 of a second cell type. In this example, the second cell type is a GEO cell type. UE 610 also receives a request for operation in the GEO cell type.

[0092] At time t3, UE 610 determines the cell type to select. In this example, the UE is configured with a priority list, where LEO is the first priority and GEO is the second priority. UE 610 also checks the operational requirements to confirm that the UE has the capability to support them. At time t4, UE 610 selects satellite 620 of the first cell type (e.g., LEO).

[0093] As indicated above, Figure 3-6 This is provided as an example. Other examples may differ from the one provided. Figure 3-5 The example described.

[0094] Figure 7 This is a flowchart illustrating a method 700 performed, for example, by a user equipment (UE) supporting a cell type selection process for a non-terrestrial network, according to various aspects of this disclosure. The operation of method 700 can be implemented by a network device or its components as described (e.g., UE 115).

[0095] like Figure 7 As shown, in some aspects, method 700 may include: selecting or reselecting a target cell of a non-terrestrial network or restoring connection to a target cell (block 702). For example, a user equipment (UE) (e.g., using antenna 252, DEMOD / MOD 254, MIMO detector 256, TX MIMO processor 266, receive processor 258, transmit processor 264, controller / processor 280, and / or memory 282) may select or reselect a target cell or restore connection. In some aspects, the target cell is a serving cell or a non-serving cell.

[0096] Method 700 may include determining the cell type of the target cell (block 704). For example, the UE (e.g., using antenna 252, DEMOD / MOD 254, MIMO detector 256, receive processor 258, controller / processor 280, and / or memory 282) may determine the cell type of the target cell. The cell type may be a low Earth orbit (LEO) cell type, a geostationary orbit (GEO) cell type, a mobile cell type, a fixed cell type, a temporarily fixed LEO cell type, or a permanently fixed LEO cell type. For example, the UE may determine the cell type based on the demodulation reference signal (DMRS) used for decoding the master information block (MIB), the scrambling code used for the physical broadcast channel (PBCH), and / or the physical cell identity (PCID). In other aspects, the UE determines the cell type based on the beam pattern configuration within the system information block (SIB) message.

[0097] Method 700 may further include: performing selection or reselection of a target cell based on cell type (block 706). For example, the UE (e.g., using antenna 252, DEMOD / MOD 254, MIMO detector 256, TX MIMO processor 266, receive processor 258, transmit processor 264, controller / processor 280, and / or memory 282) may perform selection or reselection of a target cell. In some aspects, selection or reselection or connectivity is performed only for one cell type. In other aspects, selection or reselection or connectivity is performed according to a priority set, where each priority corresponds to a different cell type.

[0098] Examples of various aspects

[0099] Aspect 1: A method for wireless communication by a user equipment (UE), comprising: selecting or reselecting a target cell of a non-terrestrial network or restoring a connection with the target cell, the target cell including a serving cell or a non-serving cell; determining a cell type of the target cell, the cell type including a low Earth orbit (LEO) cell type, a geostationary orbit (GEO) cell type, a mobile cell type, a fixed cell type, a temporarily fixed LEO cell type, or a permanently fixed LEO cell type; and performing the selection or reselection of the target cell or restoring the connection with the target cell based on the cell type.

[0100] Aspect 2: According to the method of aspect 1, wherein the cell type is determined based on the demodulation reference signal (DMRS) used for decoding the master information block (MIB), the scrambling code used for the physical broadcast channel (PBCH), and / or the physical cell identity (PCID).

[0101] Aspect 3: The method according to aspect 1 or aspect 2 further includes: performing the selection or reselection or connection only for one type of cell.

[0102] Aspect 4: The method according to any one of the preceding aspects further includes: performing the selection or the reselection or the connection according to a priority set, wherein each priority in the priority set corresponds to one of a plurality of different cell types.

[0103] Aspect 5: The method according to any one of the preceding aspects further includes: obtaining requirements for operation in the cell type, wherein the determination of the cell type is based on the requirements.

[0104] Aspect 6: The method according to aspect 5, wherein the requirement is obtained via broadcast information.

[0105] Aspect 7: The method according to aspect 6, wherein the broadcast information includes a profile identifier corresponding to the requirement for operation in the cell type.

[0106] Aspect 8: According to the method of aspect 6, wherein the broadcast information includes a physical cell identity (PCID) and / or frequency mapped to a profile identifier.

[0107] Aspect 9: According to the method of aspect 6, the broadcast information is obtained via a non-terrestrial network-specific System Information Block (SIB) message.

[0108] Aspect 10: The method according to aspect 6, wherein the requirement is associated with multiple neighboring cells in a neighboring cell list or frequencies in an inter-frequency list.

[0109] Aspect 11: The method according to aspect 6, wherein the broadcast information includes a mapping of cell ID or cell frequency to the requirement for operation in the cell type.

[0110] Aspect 12: The method according to aspect 5 further includes: disabling the target cell in response to the inability to meet the requirement for operating the cell type.

[0111] Aspect 13: According to the method of aspect 5, wherein the requirements for operation in the cell type are based on frequency compensation for addressing the Doppler effect, tracking of uplink timing pre-compensation, support for large cell sizes, support for the number of Hybrid Automatic Repeat Request (HARQ) processes exceeding a first threshold, the ability to enable and disable HARQ processes, or support for Quality of Service (QoS) specifications.

[0112] Aspect 14: The method according to aspect 13, wherein the QoS specification includes: support for a specific Service Data Adaptation Protocol (SDAP) configuration, support for a specific Packet Data Convergence Protocol (PDCP) configuration, support for PDCP drop timers exceeding a second threshold, and / or support for sequence numbers (SNs) having a length greater than a third threshold.

[0113] Aspect 15: The method according to any one of the preceding aspects further includes: reporting UE capabilities related to requirements for operation in the cell type.

[0114] Aspect 16: The method according to aspect 15 further includes: obtaining instructions for redirecting to different target cells based on the UE capabilities.

[0115] Aspect 17: The method according to any one of the preceding aspects, wherein the cell type is determined based on the beam pattern configuration within the System Information Block (SIB) message.

[0116] Aspect 18: The method according to any one of the preceding aspects further includes: obtaining a satellite communication gap configuration in response to the cell type being the permanent fixed LEO cell type.

[0117] Aspect 19: The method according to any one of the preceding aspects further includes: disabling the permanently fixed LEO cell type in response to the UE being unable to be configured with a satellite communication gap.

[0118] Aspect 20: The method according to any one of the preceding aspects, wherein the permanently fixed LEO cell type includes cells served by a first satellite and then by a second satellite after a satellite handover, wherein a satellite communication gap occurs during the satellite handover.

[0119] Aspect 21: According to the method of aspect 20, the cell identifier (ID) remains unchanged after the satellite handover.

[0120] Aspect 22: According to the method of aspect 20, the system information block (SIB) configuration and radio resource control (RRC) configuration remain unchanged after the satellite handover, and communication is resumed after the satellite communication gap.

[0121] Aspect 23: The method according to aspect 20 further includes: obtaining an indication of the duration of the satellite communication gap.

[0122] Aspect 24: The method according to aspect 20 further includes: obtaining a system information block (SIB), the SIB including a cell stop time serving as the starting point of the satellite communication gap.

[0123] Aspect 25: An apparatus for wireless communication by a user equipment (UE), comprising: at least one processor, a memory coupled to the at least one processor; and instructions stored in the memory and operable, when executed by the at least one processor, to cause the apparatus to: select or reselect a target cell of a non-terrestrial network or restore a connection with the target cell, the target cell including a serving cell or a non-serving cell; determine a cell type of the target cell, the cell type including a low Earth orbit (LEO) cell type, a geostationary orbit (GEO) cell type, a mobile cell type, a fixed cell type, a temporarily fixed LEO cell type, or a permanently fixed LEO cell type; and perform the selection or reselection of the target cell or the restoration of the connection with the target cell based on the cell type.

[0124] Aspect 26: The apparatus according to aspect 25, wherein the at least one processor causes the apparatus to perform the following operation: determining the cell type based on the demodulation reference signal (DMRS) for decoding the master information block (MIB), the scrambling code for the physical broadcast channel (PBCH), and / or the physical cell identity (PCID).

[0125] Aspect 27: The apparatus according to aspect 25 or aspect 26, wherein the permanently fixed LEO cell type includes cells served by a first satellite and then by a second satellite after a satellite handover, wherein a satellite communication gap occurs during the satellite handover.

[0126] Aspect 28: The apparatus according to any one of Aspects 25-27, wherein the cell identifier (ID) remains unchanged after the satellite handover.

[0127] Aspect 29: The apparatus according to any one of aspects 25-28, wherein the at least one processor is further configured to: obtain an indication of the duration of the satellite communication gap.

[0128] Aspect 30: A user equipment including a unit for performing operations according to one or more aspects 1-24.

[0129] Aspect 31: A user equipment including a transceiver, a memory, and at least one processor configured to perform operations of one or more aspects of aspects 1-24.

[0130] Aspect 32: A computer-readable medium for wireless communication by a user equipment (UE), comprising code executable by the UE to perform operations of one or more aspects of aspects 1-24.

[0131] The foregoing disclosure provides illustrations and descriptions, but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and changes may be made based on the foregoing disclosure, or may be derived from implementation of the aspects.

[0132] As used, the term "component" is intended to be interpreted broadly as hardware, firmware, and / or a combination of hardware and software. As used, a processor is implemented in a combination of hardware, firmware, and / or hardware and software.

[0133] Some aspects are described in conjunction with thresholds. As used, depending on the context, satisfying a threshold can refer to a value greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, etc.

[0134] It will be apparent that the described systems and / or methods can be implemented in various forms, including hardware, firmware, and / or combinations of hardware and software. The actual, specialized control hardware or software code used to implement these systems and / or methods is not a limitation in any respect. Therefore, the operation and behavior of the systems and / or methods are described without reference to specific software code—it is to be understood that the software and hardware can be designed to implement the systems and / or methods, at least in part, based on the description.

[0135] Even if a particular combination of features is recited in the claims and / or disclosed in the description, these combinations are not intended to limit the disclosure of the aspects. In fact, many of these features can be combined in ways not expressly recited in the claims and / or not disclosed in the description. While each dependent claim listed below may depend directly on only one claim, the disclosure of an aspect includes every dependent claim combined with every other claim in the claim set. The phrase “at least one of” in the list of entries refers to any combination of these entries, including single members. For example, “at least one of a, b, or c” is intended to cover: a, b, c, ab, ac, bc, and abc, as well as any combination of the same elements with multiples (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, and ccc, or any other ordering of a, b, and c).

[0136] Unless explicitly stated otherwise, the elements, actions, or instructions used should not be construed as definitive or essential. Furthermore, as used, the articles “a” and “an” are intended to include one or more entries and can be used interchangeably with “one or more.” Additionally, as used, the terms “set” and “group” are intended to include one or more entries (e.g., related entries, unrelated entries, combinations of related and unrelated entries, etc.) and can be used interchangeably with “one or more.” Where only one entry is intended, the phrase “only one” or similar language is used. Furthermore, as used, the terms “has,” “have,” “having,” etc., are intended to be open-ended terms. Further, unless explicitly stated otherwise, the phrase “based on” is intended to mean “at least partially based on.”

Claims

1. A method for wireless communication by a user equipment (UE), comprising: Restore connection to the target cell on the non-terrestrial network; as well as The connection to the target cell is completed based on cell type, which includes a permanently fixed LEO cell type, wherein the permanently fixed LEO cell type is associated with a cell served by a first satellite and then by a second satellite after a satellite handover, wherein a satellite communication gap occurs during the satellite handover, and the first and second satellites have the same cell identifier.

2. The method according to claim 1, wherein, The first satellite and the second satellite have the same System Information Block (SIB) configuration.

3. The method according to claim 1, wherein, The UE communicates using a Radio Resource Control (RRC) configuration that remains unchanged after the satellite handover and resumes communication after the satellite communication gap.

4. The method according to claim 1, further comprising: Receive an indication of the duration of the satellite communication gap; as well as Suspend communication during the satellite communication gap based on the duration stated.

5. The method according to claim 1, wherein, The satellite communication gaps include suspended Radio Resource Control (RRC) connections.

6. The method according to claim 1, further comprising: Since the cell type is the permanently fixed LEO cell type, the satellite communication gap configuration is applied.

7. The method according to claim 1, further comprising: Receive System Information Block (SIB), the SIB including the time as the start point of the satellite communication gap.

8. The method according to claim 1, further comprising: Receive System Information Block (SIB), the SIB including the time as the end point of the satellite communication gap.

9. A user equipment (UE), comprising: At least one transceiver; At least one memory, comprising instructions; and At least one processor is configured to execute the instructions to cause the UE to perform the following operations: Reconnection to the target cell on a non-terrestrial network is restored via the at least one transceiver; as well as The connection to the target cell is established via the at least one transceiver based on a cell type, the cell type including a permanently fixed LEO cell type, wherein the permanently fixed LEO cell type is associated with a cell served by a first satellite and then by a second satellite after a satellite handover, wherein a satellite communication gap occurs during the satellite handover, and the first and second satellites have the same cell identifier.

10. The UE according to claim 9, wherein, The at least one processor also enables the UE to: communicate via the at least one transceiver using a Radio Resource Control (RRC) configuration that remains unchanged after the satellite handover, and to resume communication via the at least one transceiver after the satellite communication gap.

11. The UE according to claim 9, wherein, The first satellite and the second satellite have the same System Information Block (SIB) configuration.

12. The UE according to claim 9, wherein, The at least one processor also enables the UE to receive an indication of the duration of the satellite communication gap via the at least one transceiver, and to suspend communication during the satellite communication gap based on the duration.

13. The UE according to claim 9, wherein, The satellite communication gaps include suspended Radio Resource Control (RRC) connections.

14. The UE according to claim 9, wherein, The at least one processor also enables the UE to receive satellite communication gap configuration via the at least one transceiver, since the cell type is the permanently fixed LEO cell type.

15. The UE according to claim 9, wherein, The at least one processor also enables the UE to receive a System Information Block (SIB) via the at least one transceiver, the SIB including the time as the start point of the satellite communication gap.

16. The UE according to claim 9, wherein, The at least one processor also enables the UE to receive a System Information Block (SIB) via the at least one transceiver, the SIB including the time as the end point of the satellite communication gap.

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