Spectrum sharing through spatial domain interference suppression
Spatial domain interference suppression techniques address inefficiencies in spectrum sharing between terrestrial and non-terrestrial networks by mitigating interference, enhancing spectral efficiency and ensuring consistent service delivery across diverse QoS scenarios.
Patent Information
- Application Number
- PCT/CN2024/119662
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-08-12
- Filing Date
- 2024-09-19
- Publication Date
- 2026-02-19
AI Technical Summary
Existing wireless communication networks face inefficiencies in spectrum sharing due to interference between terrestrial and non-terrestrial networks, leading to disparities in service delivery and limited spectral efficiency, particularly in scenarios with diverse Quality of Service (QoS) requirements and limited spectrum resources.
Implementing spatial domain interference suppression techniques, including filtering and power level optimization, to mitigate interference between terrestrial and non-terrestrial networks, utilizing assistance information to estimate and weaken interfering signals.
Enhances spectral efficiency and reduces interference, enabling effective spectrum sharing and improved service delivery across networks with diverse QoS requirements without requiring significant bandwidth or infrastructure changes.
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Figure CN2024119662_19022026_PF_FP_ABST
Abstract
Description
SPECTRUM SHARING THROUGH SPATIAL DOMAIN INTERFERENCE SUPPRESSION
[0001] CROSS-REFERENCE TO RELATED APPLICATIONS
[0002] The present disclosure claims priority to US Provisional Patent Application No. 63 / 682,167, filed August 12, 2024, the contents of which are hereby incorporated herein by reference.TECHNICAL FIELD
[0003] The present disclosure relates, generally, to spectrum sharing among networks and, in particular embodiments, to spatial domain interference suppression to facilitate such spectrum sharing.BACKGROUND
[0004] In wireless communications networks, Orthogonal Multiple Access (OMA) techniques are known to exhibit relatively low spectral efficiency due to an inability of users to share resources. Consequently, those users with favorable channel conditions may receive preferential treatment, while those users with poor conditions may experience inadequate service, leading to disparities and delays in service delivery. This limitation renders traditional OMA approaches insufficient for sixth generation (6G) wireless communications networks. This insufficiency may be shown to be especially acute in scenarios in which multiple networks operate on limited spectrum resources. The limitations may be shown to hinder establishment of numerous mobile and IoT connections with diverse Quality of Service (QoS) requirements.
[0005] In contrast, Non-Orthogonal Multiple Access (NOMA) systems leverage power domain multiplexing or code domain multiplexing to facilitate resource sharing among multiple users, thereby achieving enhanced spectral efficiency, reduced transmission latency, and extensive connectivity. Two primary NOMA variants are Power-Domain NOMA (PD-NOMA) and Code-Domain NOMA (CD-NOMA) . Each variant may be shown to offer unique advantages. Beyond these two primary NOMA variants, NOMA encompasses additional variants such as Pattern Division Multiple Access (PDMA) , Spatial Division Multiple Access (SDMA) and Bit Division Multiplexing (BDM) . The additional variants may be shown to provide low latency, dense service provision, fairness, innovative waveform architecture, efficient bandwidth utilization and support for massive device connectivity, when compared to traditional access schemes.
[0006] PD-NOMA involves a dynamic allocation of varying power levels to users based on their channel conditions, utilizing the same time resources, frequency resources, space resources and code resources at the transmitter end. Unlike CD-NOMA, PD-NOMA does not require additional bandwidth for enhanced spectral efficiency and boasts straightforward implementation without necessitating network modifications. Conversely, CD-NOMA employs sparse or non-orthogonal spreading sequences tailored to individual users to minimize cross-correlation coefficients. While CD-NOMA enhances spectral efficiency, applicability of CD-NOMA to existing systems is challenging due to a requirement for increased transmission bandwidth. Ultimately, PD-NOMA emerges as a promising solution for efficient resource allocation and spectral efficiency improvement without imposing significant bandwidth demands or infrastructure alterations.SUMMARY
[0007] Aspects of the present application endeavor to suppress interference to, thereby, facilitate spectrum sharing. An apparatus in a first network may receive assistance information from a second network. For example, the first network may be one of the TN and the NTN and the second network may be the other of the TN and the NTN. The apparatus may obtain, using the assistance information, an estimate for a direction of an interfering signal from the second network. The apparatus may apply a filtering technique to weaken the direction of the interfering signal, thereby reducing interference with a desired signal arriving from an estimated direction of the desired signal.
[0008] Spectrum sharing among a TN and a NTN is known to lead to spatial domain interference. The same may be said to be true of sharing among one TN and another TN. The same may be said to be true of sharing among one NTN and another NTN.
[0009] Aspects of the present application introduce interference mitigation strategies for scenarios with shared and / or adjacent spectra between, for example, satellites and terrestrial gNBs. Aspects of the present application also introduce a low complexity full frequency reuse mechanism between TN and NTN. Aspects of the present application propose a low complexity spatial interference suppression at TN and NTN. Aspects of the present application propose a signaling mechanism within TN devices and NTN devices to minimize the received interference at both networks.
[0010] According to an aspect of the present disclosure, there is provided a communication method for spectrum sharing between a first network and a second network. The method includes receiving, at an apparatus of the first network, assistance information related to the second network, obtaining, at the apparatus based, at least in part, on the assistance information, an estimated direction of an interfering signal from the second network and applying a spatial domain filtering technique to weaken the estimated direction of the interfering signal.
[0011] According to an aspect of the present disclosure, there is provided a communication method for spectrum sharing between a first network and a second network. The method includes receiving, at a user equipment of the first network and from a gNB of the first network, an indication of a first-network muted time interval, measuring, at the user equipment of the first network, would-be interfering signals during the first-network muted time interval and obtaining measurements of the would-be interfering signals received during the first-network muted time interval and processing, at the user equipment of the first network, the measurements of the would-be interfering signals to, thereby, identify characteristics of the interfering signal.
[0012] According to an aspect of the present disclosure, there is provided a communication method for spectrum sharing between a first network and a second network. The method includes transmitting, from a gNB of the first network and to a gNB of the second network, an indication of first network transmission characteristics, receiving, at the gNB of the first network and from the gNB of the second network, an indication of second network transmission characteristics, optimizing, at the gNB of the first network, first network power levels for first network users and transmitting, at the gNB of the first network, signals to the first network users, based upon the first network power levels.BRIEF DESCRIPTION OF THE DRAWINGS
[0013] For a more complete understanding of the present embodiments, and the advantages thereof, reference is now made, by way of example, to the following descriptions taken in conjunction with the accompanying drawings, in which:
[0014] FIG. 1 illustrates, in a schematic diagram, a communication system in which embodiments of the disclosure may occur, the communication system includes multiple example electronic devices and multiple example transmit receive points along with various networks;
[0015] FIG. 2 illustrates, in a block diagram, the communication system of FIG. 1, the communication system includes multiple example electronic devices, an example terrestrial transmit receive point and an example non-terrestrial transmit receive point along with various networks;
[0016] FIG. 3 illustrates, as a block diagram, an example of an apparatus wirelessly communicating with another apparatus in the communication system of FIG. 1, in accordance with aspects of the present application;
[0017] FIG. 4 illustrates, as a block diagram, an example of an apparatus that may be a communication device or an apparatus implemented in a communication device in the communication system of FIG. 1, in accordance with aspects of the present application;
[0018] FIG. 5 illustrates, as a block diagram, an example apparatus that may include corresponding modules or units configured to implement methods and / or embodiments described herein, in accordance with aspects of the present application;
[0019] FIG. 6 illustrates a network that differs from the network illustrated in FIG. 2 in the addition of a sensing agent, in accordance with aspects of the present application;
[0020] FIG. 7 illustrates, as a block diagram, a sensing management function, in accordance with aspects of the present application;
[0021] FIG. 8 illustrates an example network in which terrestrial transmit and receive points (T-TRPs) are communicating with non-terrestrial TRPs (NT-TRPs) that are part of a satellite constellation, in accordance with aspects of the present application;
[0022] FIG. 9 illustrates an example network in which the satellite constellation effectively acts as the gateway for the T-TRPs on the ground, in accordance with aspects of the present application;
[0023] FIG. 10 illustrates an example network in which the NT-TRPs communicate with the T-TRPs through a core network, in accordance with aspects of the present application;
[0024] FIG. 11 illustrates an example of a channel model of a multiple-input multiple-output (MIMO) system, in accordance with aspects of the present application;
[0025] FIG. 12 illustrates a base station in communication with a user equipment (UE) , in accordance with aspects of the present application;
[0026] FIG. 13 illustrates a basic example for reflective intelligent surface (RIS) utilization in beamforming, in accordance with aspects of the present application;
[0027] FIG. 14A illustrates a scenario wherein only some of the time slots used by one network coincide with the time slots or frequency bands used by the other network, in accordance with aspects of the present application;
[0028] FIG. 14B illustrates a scenario wherein the resources are fully synchronized across the time dimension, in accordance with aspects of the present application;
[0029] FIG. 15 illustrates, in a flow diagram, example steps in a method, in accordance with aspects of the present application;
[0030] FIG. 16 illustrates, in a flow diagram, example steps in another method, in accordance with aspects of the present application;
[0031] FIG. 17 illustrates, in a flow diagram, an attempt to achieve the goal of minimizing interference introduced at a T-gNB, in accordance with aspects of the present application;
[0032] FIG. 18 illustrates, in a flow diagram, an attempt to achieve the goal of minimizing interference introduced at a NT-gNB, in accordance with aspects of the present application;
[0033] FIG. 19 illustrates a scenario that relates to a sharing scenario, wherein terrestrial network (TN) downlink (DL) and non-terrestrial network (NTN) uplink (UL) share some resources, in accordance with aspects of the present application;
[0034] FIG. 20 illustrates, in a flow diagram, example steps in an attempt to achieve the goal of minimizing interference introduced at the NTN UE in the scenario illustrated in FIG. 19, in accordance with aspects of the present application;
[0035] FIG. 21 illustrates, in a flow diagram, example steps in an attempt to achieve the goal of minimizing interference introduced at the TN UE in the scenario illustrated in FIG. 19, in accordance with aspects of the present application;
[0036] FIG. 22 illustrates, in a flow diagram, example steps in an attempt to achieve the goal of minimizing interference introduced at the T-gNB in the scenario illustrated in FIG. 19, in accordance with aspects of the present application;
[0037] FIG. 23 illustrates, in a flow diagram, example steps in an attempt to achieve the goal of minimizing interference introduced at the NT-gNB in the scenario illustrated in FIG. 19, in accordance with aspects of the present application;
[0038] FIG. 24 illustrates, in a flow diagram, an attempt to achieve the goal of minimizing interference introduced at a T-gNB, in accordance with aspects of the present application;
[0039] FIG. 25 illustrates, in a flow diagram, an attempt to achieve the goal of minimizing interference introduced at a NT-gNB, in accordance with aspects of the present application;
[0040] FIG. 26A illustrates an NTN device and a TN device, wherein the NTN device communicates with an NTN UE and interference signals may arrive at the NTN UE from the TN device, in accordance with aspects of the present application;
[0041] FIG. 26B illustrates the NTN device and the TN device of FIG. 26A, in accordance with aspects of the present application;
[0042] FIG. 27 illustrates, in a flow diagram, a gNB in one network indicating, to a UE in the same network, muted periods, in accordance with aspects of the present application; and
[0043] FIG. 28 illustrates, in a flow diagram, a T-gNB in bidirectional communication with a satellite, in accordance with aspects of the present application.DETAILED DESCRIPTION
[0044] For illustrative purposes, specific example embodiments will now be explained in greater detail in conjunction with the figures.
[0045] The embodiments set forth herein represent information sufficient to practice the claimed subject matter and illustrate ways of practicing such subject matter. Upon reading the following description in light of the accompanying figures, those of skill in the art will understand the concepts of the claimed subject matter and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure and the accompanying claims.
[0046] Moreover, it will be appreciated that any module, component, or device disclosed herein that executes instructions may include, or otherwise have access to, a non-transitory computer / processor readable storage medium or media for storage of information, such as computer / processor readable instructions, data structures, program modules and / or other data. A non-exhaustive list of examples of non-transitory computer / processor readable storage media includes magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, optical disks such as compact disc read-only memory (CD-ROM) , digital video discs or digital versatile discs (i.e., DVDs) , Blu-ray DiscTM, or other optical storage, volatile and non-volatile, removable and non-removable media implemented in any method or technology, random-access memory (RAM) , read-only memory (ROM) , electrically erasable programmable read-only memory (EEPROM) , flash memory or other memory technology. Any such non-transitory computer / processor storage media may be part of a device / apparatus or accessible or connectable thereto. Computer / processor readable / executable instructions to implement a method, an application or a module described herein may be stored or otherwise held by such non-transitory computer / processor readable storage media.
[0047] Referring to FIG. 1, as an illustrative example, a simplified schematic illustration of a communication system is provided. The communication system 100 may comprise a radio access network 120. The radio access network (RAN) 120 may be a next generation (e.g., sixth generation (6G) or later) radio access network, or a legacy (e.g., fifth generation (5G) , fourth generation (4G) , third generation (3G) or second generation (2G) ) radio access network. The RAN 120 may be a network using other radio access technology. In some implementations, 6G radio access refers to a next generation air interface of standards which may comprise both terrestrial networks (TNs) and non-terrestrial networks (NTNs) , and more details will be described below. One or more communication electronic device (ED) 110a, 110b, 110c, 110d, 110e, 110f, 110g, 110h, 110i, 110j (generically referred to as 110) may be interconnected to one another or connected to one or more network nodes 170a, 170b (generically referred to as 170) , in the RAN 120. A core network (CN) 130 may be a part of the communication system and may be dependent or independent of the radio access technology used in the communication system 100. The communication system 100 may also comprise a public switched telephone network (PSTN) 140, the internet 150, and other networks 160.
[0048] In general, the communication system 100 enables communication of multiple wireless or wired elements. The communication system 100 may provide content, such as voice, data, video and / or text, via broadcast, multicast, groupcast and unicast, etc. The communication system 100 may operate by sharing resources, such as carrier spectrum bandwidth, among its constituent elements. The communication system 100 may provide a wide range of communication services and applications including enhanced Mobile Broadband (eMBB) services, ultra-reliable low-latency communication (URLLC) services, massive machine type communication (mMTC) services, integrated sensing and communication (ISAC) , immersive communication, massive communication, Hyper reliable and low-latency communication, ubiquitous connectivity, integrated AI and communication, and other services that can be provided by a future generation communication system. The communication system 100 may provide other applications (such as earth monitoring, remote sensing, passive sensing and positioning, navigation and tracking, autonomous delivery and mobility, etc. ) . The communication system 100 may include a terrestrial communication system (or network) and / or a non-terrestrial communication system (or network) . The communication system 100 may provide a high degree of availability and robustness through a joint operation of a terrestrial communication system and a non-terrestrial communication system. For example, integrating a non-terrestrial communication system (or components thereof) into a terrestrial communication system can result in a heterogeneous network comprising multiple layers. The heterogeneous network may achieve better overall performance through efficient multi-link joint operation, more flexible functionality sharing and faster physical layer link switching between terrestrial networks and non-terrestrial networks. The terrestrial communication system and the non-terrestrial communication system could be considered sub-systems of the communication system 100.
[0049] FIG. 2 illustrates another example for the communication system 100. As described earlier, the communication system 100 may include EDs 110a, 110b, 110c, 110d (generically referred to as ED 110) , RANs 120a, 120b, and one or more of a CN 130, a PSTN 140, the Internet 150 and other networks 160. In addition, the communication system 100 may also include a non-terrestrial network (NTN) 120c. The RANs 120a, 120b may include respective network nodes 170a, 170b such as base stations 170a, 170b, which may be generically referred to as terrestrial network (TN) devices or terrestrial transmit and receive points (T-TRPs) 170a, 170b (generically referred to as 170) . As referred to herein, the terms “TRP” and “base station” may be used interchangeably unless explicitly noted otherwise in a given example or section. For brevity, this disclosure may primarily refer to base station; however, absent an explicit limitation, references to TRP are merely non-limiting instances of interchangeable use. The T-TRPs 170a, 170b may be base stations mounted on a building or tower. In one implementation, the NTN 170c includes a RAN node such as base station 172, which may be generically referred to as an NTN device, a non-terrestrial node, a non-terrestrial network device, a non-terrestrial base station, or a non-terrestrial transmit and receive point (NT-TRP) 172. In some implementations, the NT-TRP 172 is not attached to ground, for example, in the case of an airborne base station. An airborne base station may be implemented using communication equipment supported or carried by a flying device. For example, a flying device may include an airborne platform (e.g., a blimp or an airship) , balloon, drone (e.g., quadcopter) , and other types of aerial vehicles. In some implementations, an airborne base station may be supported or carried by an unmanned aerial system (UAS) or an unmanned aerial vehicle (UAV) , such as a drone. An airborne base station may be a moveable or mobile base station that can be flexibly deployed in different locations to meet demand. A satellite base station is another example of a non-terrestrial base station. A satellite base station may be implemented using communication equipment supported or carried by a satellite. A satellite base station may also be referred to as an orbiting base station. High altitude platforms are yet another example of non-terrestrial base stations, including international mobile telecommunication base stations.
[0050] As referred to herein, and unless specified otherwise, a “TRP” may also refer to a T-TRP or an NT-TRP, a “T-TRP” may also refer to a “TN TRP” , and an “NT-TRP” may also refer to an “NTN TRP” . The NTN 120c may be considered to be a radio access network (RAN) , with operational aspects in common with the RANs 120a, 120b. The NTN 120c may include at least one NTN device and at least one corresponding terrestrial network device. The at least one NTN device may function as a transport layer device and the at least one corresponding terrestrial network device may function as a RAN node, which communicates with the ED 110 via the non-terrestrial network device. In addition, there may be an NTN gateway on the ground (i.e., referred to as a terrestrial network device) that also functions as a transport layer device to communicate with both the NTN device and the RAN node. The RAN node may communicate with the ED 110 via the NTN device and the NTN gateway. In some implementations, the NTN gateway and the RAN node may be located in the same device.
[0051] A base station (also referred to as a TRP as stated above) 170 may be a network element in radio access network responsible for radio transmission and reception in one or more cells to or from the user equipment. The base station 170 may be known by other names in some implementations, such as a base transceiver station (BTS) , a radio base station, a network node, a network device, a device on the network side, a transmit / receive node, a Node B, an evolved NodeB (eNodeB or eNB) , a Home eNodeB, a next Generation NodeB (gNB) , a transmission point (TP) , a site controller, an access point (AP) , a wireless router, a relay station, a terrestrial node, a terrestrial network device, a terrestrial base station, a positioning node, among other possibilities. The base station 170 may be a macro base station (BS) , a pico BS, a relay node, a donor node, or the like, or combinations thereof. When a base station 170 performs (or is configured to perform) a method described herein, it may be interpreted as the base station, one or more modules (or units) in the base station, a circuit or chip, or a combination thereof, may perform the method. For example, the circuit or chip may include a modem chip, also referred to as a baseband chip, a system on chip (SoC) including a modem core, system in package (SIP) ) , and the like, and may be responsible for one or more communication functions in the base station.
[0052] The EDs 110a-110d and TRPs 170a-170b, 172 are examples of communication equipment that can be configured to implement some or all of the operations and / or embodiments described herein. The T-TRP 170a forms part of the RAN 120a, which may include other TRPs, and / or other devices. Also, the TRP 170b forms part of the RAN 120b, which may include other TRPs, and / or devices. Each TRP 170a, 170b may transmit and / or receive wireless signals within a particular geographic region or area, sometimes referred to as a “cell” or “coverage area” . The TRPs 170a-170b may be responsible for allocating and / or configuring resources and transmission and / or reception in a set of cells. A cell may be a Radio network object that can be uniquely identified from a (cell) identification that is broadcasted over a geographical region or area from base stations associated with the cell. A cell can be either FDD or TDD mode. A cell may also refer to the carrier frequencies within the DL / UL carrier bandwidth resources of a single standalone carrier or a component carrier in a carrier aggregation mode. A cell may be further divided into cell sectors, and a base station 170a-170b may, for example, employ multiple transceivers to provide service to multiple sectors. In some implementations, there may be established pico or femto cells where the radio access technology supports such. In some implementations, multiple transceivers could be used for each cell, for example using multiple-input multiple-output (MIMO) technology. The number of RAN 120a-120b shown is an example only. Any number of RAN may be contemplated when devising the communication system 100.
[0053] Any base station may be a single element, as shown, or multiple elements, distributed in the corresponding RAN, or otherwise. In some implementations, a plurality of RAN nodes coordinate to assist the ED 110 in implementing radio access, and different RAN nodes separately implement different functions of the base station. For example, the RAN node may be a central unit (CU) , a distributed unit (DU) , a CU-control plane (CP) , a CU-user plane (UP) , or a radio unit (RU) etc. The CU and the DU may be separately deployed, or may be included in a same element (i.e., a baseband unit (BBU) ) . The RU may be included in a radio frequency device or a radio frequency unit (i.e., a remote radio unit (RRU) , an active antenna unit (AAU) , or a remote radio head (RRH) ) . In different systems, the CU (or the CU-CP and the CU-UP) , the DU, or the RU may also have different names, but a person skilled in the art may understand meanings thereof. For example, in an open radio access network (ORAN) system, a CU may also be referred to as an open CU (O-CU) , a DU may also be referred to as an open DU (O-DU) , and a CU-CP may also be referred to as an open CU-CP (O-CU-CP) . The CU-UP may also be referred to as an open CU-UP (O-CU-UP) , and the RU may also be referred to as an open RU (O-RU) . Any one of the CU (or the CU-CP, the CU-UP) , the DU, and the RU may be implemented by using a software module, a hardware module, or a combination of a software module and a hardware module.
[0054] Further, communication (s) between different devices / apparatuses in various embodiments of this application may refer to direct communication between different devices / apparatuses (that is, no forwarding is required by another device / apparatuses) , or may refer to communication (s) between different devices / apparatuses via another device / apparatus (that is, forwarding is required by another device / apparatus) . Alternatively, such further communication (s) may refer to that a functional unit inside the device / apparatus uses another functional unit in the device / apparatus to communicate with another device / apparatus. In other words, “sending (or transmitting) information to... (an ED or a base station) ” in this application may be understood as that a destination endpoint of the information is an ED or a base station. It may include sending / transmitting information directly or indirectly to an ED or a base station. Similarly, “receiving information from... (an ED or a base station) ” may be understood as that a source endpoint of the information is an ED or a base station, and may include directly or indirectly receiving information from an ED or a base station. Necessary processing such as format conversion, digital-to-analog conversion, amplification, and filtering may be performed on the information between the source endpoint that sends the information and the destination endpoint. However, the destination endpoint may understand valid information from the source endpoint. Similar descriptions in this application may be understood similarly. Details are not described herein again. In the present disclosure, the terms “send” and “transmit” may be used interchangeably in embodiments of this application.
[0055] The ED 110 is used to connect persons, objects, machines, etc. The ED 110 may be widely used in various scenarios including, for example, cellular communications, device-to-device (D2D) , vehicle to everything (V2X) , peer-to-peer (P2P) , machine-to-machine (M2M) , MTC, internet of things (IoT) , virtual reality (VR) , augmented reality (AR) , mixed reality (MR) , metaverse, digital twin, industrial control, self-driving, remote medical, smart grid, smart furniture, smart office, smart wearable, smart transportation, smart city, drones, robots, remote sensing, passive sensing, positioning, navigation and tracking, autonomous delivery and mobility, etc.
[0056] Each ED 110 represents any suitable end user device for wireless operation and may include such devices (or may be referred to but not limited to) as a user equipment (UE) or a user device or a terminal device, a wireless transmit / receive unit (WTRU) , a mobile station, a fixed or mobile subscriber unit, a cellular telephone, a station (STA) , a MTC device, a personal digital assistant (PDA) , a smartphone, a laptop, a computer, a tablet, a wireless sensor, a consumer electronics device, a smart book, a vehicle, a car, a truck, a bus, a train, or an IoT device, wearable devices (such as a watch, a pair of glasses, head mounted equipment, etc. ) , an industrial device, or an apparatus in (e.g., module, modem, or chip) or comprising the forgoing devices, among other possibilities. Future generation EDs 110 may be referred to using other terms. When an ED 110 performs (or is configured to perform) a method described herein, it may be interpreted as the ED, one or more module (or units) in the ED, a circuit or chip, or a combination thereof, may perform the method. For example, the circuit or chip may include a modem chip, also referred to as a baseband chip, a system on chip (SoC) including a modem core, or system in package (SIP) ) , and the like, and may be responsible for one or more communication functions in the ED.
[0057] Each ED 110 connected to TRPs 170a-170b, and / or TRPs 172 can be dynamically or semi-statically turned-on (i.e., established, activated or enabled) , turned-off (i.e., released, deactivated or disabled) and / or configured in response to one of more of: connection availability; and connection necessity.
[0058] Any ED 110 may be alternatively or additionally configured to interface, access, or communicate with any TRP 170a, 170b and 172, the Internet 150, the CN 130, the PSTN 140, the other networks 160, or any combination of the preceding. In some examples, the ED 110a may communicate an uplink (UL) and / or downlink (DL) transmission over a terrestrial air interface 190a with a station-TRP 170a. In some examples, the EDs 110a, 110b, 110c and 110d may also communicate directly with one another via one or more sidelink (SL) air interfaces 190b. In some examples, the ED 110d may communicate a UL and / or a DL transmission over a non-terrestrial air interface 190c with the NT-TRP 172.
[0059] An air interface (e.g., 190a, 190b, 190c) generally includes a number of components and associated parameters that collectively specify how a transmission is to be sent and / or received over a wireless communications link between two or more communicating devices such as ED and base station. For example, an air interface may include one or more components defining the waveform (s) , frame structure (s) , multiple access scheme (s) , protocol (s) , coding scheme (s) and / or modulation scheme (s) for conveying information (e.g., data) over a wireless communications link. The air interfaces 190a and 190b may use similar communication technology, such as any suitable radio access technology.
[0060] The non-terrestrial air interface 190c can enable communication between the EDs 110a, 110d and one or multiple NT-TRPs 172 via a wireless link or simply a link. For some examples, the link is a dedicated connection for unicast transmission, a connection for broadcast transmission or a connection between a group of EDs 110 and one or multiple NT-TRPs 172 for multicast transmission.
[0061] The TRPs 170a-170b, 172 may communicate with one another over one or more air interfaces 190e, 190f using wireless communication links (e.g., radio frequency (RF) , microwave, infrared (IR) , etc. ) or wired communication links. The air interfaces 190e, 190f may utilize any suitable radio access technology and may be substantially similar to the air interfaces 190a, 190c over which the EDs 110a-110d communicate with one or more of the TRP 170a-170b, 172 or they may be substantially different. For example, the communication system 100 may implement one or more channel access methods, such as code division multiple access (CDMA) , time division multiple access (TDMA) , frequency division multiple access (FDMA) , orthogonal FDMA (OFDMA) or single-carrier FDMA (SC-FDMA) .
[0062] The RANs 120a and 120b are in communication with the CN 130 to provide the EDs 110a, 110b and 110c with various services such as voice, data and other services. The RANs 120a and 120b and / or the CN 130 may be in direct or indirect communication with one or more other RANs (not shown) , which may or may not be directly served by the CN 130 and may, or may not, employ the same radio access technology as RAN 120a, RAN 120b or both. The CN 130 may also serve as a gateway access between (i) the RANs 120a and 120b or EDs 110a, 110b and 110c or both, and (ii) other networks (such as the PSTN 140, the Internet 150, and the other networks 160) . In addition, some or all of the EDs 110a, 110b and 110c may include functionality for communicating with different wireless networks over different wireless links using different wireless technologies and / or protocols. Instead of wireless communication (or in addition thereto) , the EDs 110a, 110b and 110c may communicate via wired communication channels to a service provider or switch (not shown) and to the Internet 150. The PSTN 140 may include circuit switched telephone networks for providing plain old telephone service (POTS) . The Internet 150 may include a network of computers and subnets (intranets) or both and incorporate protocols, such as Internet Protocol (IP) , Transmission Control Protocol (TCP) , User Datagram Protocol (UDP) . The EDs 110a, 110b and 110c may be multimode devices capable of operation according to multiple radio access technologies and incorporate multiple transceivers necessary to support such.
[0063] In addition, the communication system 100 may comprise a sensing agent (not shown) to manage the sensed data from ED 110 and / or any one of TRPs 170 a-170b, 172. In one implementation, the sensing agent may be part of any one of TRPs 170 a-b, 172. In another implementation, the sensing agent is a separate node that can communicate with the CN 130 and / or the RAN 120 (e.g., any one of TRPs 170a, 170b, 172) .
[0064] FIG. 3 illustrates an example of an apparatus 310 wirelessly communicating with another apparatus 320 in a communication system (e.g., the communication system 100) . The apparatus 310 may be an electronic device (e.g., ED 110) . The apparatus 320 may be a network node (e.g., network node 170) such as a T-TRP 170 or an NT-TRP 172. Although there is only one apparatus 310 and one other apparatus 320 shown in the figure, the number of apparatus 310 and / or 320 could be one or more. For example, one ED 110 may be served by only one T-TRP 170 (or only one NT-TRP 172) , by more than one T-TRP 170 (or more than one NT-TRP 172) . One ED 110 may be served by one or more T-TRP 170 and one or more NT-TRP172. Similarly, one T-TRP 170 (or one NT-TRP172) may serve one or more ED 110.
[0065] The apparatus 310 includes at least one processor 210. Only one processor 210 is illustrated to avoid congestion in the drawing. The apparatus 310 may further include a transmitter 201 and a receiver 203 coupled to one or more antennas 204. Only one antenna 204 is illustrated to avoid congestion in the drawing. One, some, or all of the antennas 204 may, alternatively, be panels. The transmitter 201 and the receiver 203 may be integrated, e.g., as a transceiver. The transceiver is configured to modulate data or other content for transmission by at least one antenna 204 or network interface controller (NIC) . The transceiver is also configured to demodulate data or other content received by the at least one antenna 204. Each transceiver includes any suitable structure for generating signals for wireless or wired transmission and / or processing signals received wirelessly or by wire. Each antenna 204 includes any suitable structure for transmitting and / or receiving wireless or wired signals. The apparatus 310 may include at least one memory 208. Only the transmitter 201, the receiver 203, the processor 210, the memory 208 and the antenna 204 is illustrated for simplicity, but the apparatus 310 may include one or more other components. In present disclosure, the transceiver (or the transmitter 201 and / or the receiver 203) may be viewed as an interface circuit.
[0066] The memory 208 stores instructions used to perform operations described herein. The memory 208 may also store data used, generated or collected by the apparatus 310. For example, the memory 208 could store software instructions or modules configured to implement some or all of the functionality and / or embodiments described herein and that are executed by one or more processor 210.
[0067] The apparatus 310 may further include one or more input / output devices (not shown) or interfaces. The input / output devices or interfaces permit interaction with a user or other devices in the network. Each input / output device or interface includes any suitable structure for providing information to, or receiving information from a user and / or for network interface communications. Suitable structures include, for example, a speaker, microphone, keypad, keyboard, display, touch screen, etc.
[0068] The processor 210 may perform (or control the apparatus 310 to perform) operations (or methods) described herein as being performed by the apparatus 310. For example, the processor 210 performs or controls the apparatus 310 to perform receiving transport blocks (TBs) , using a resource for decoding of one of the received TBs, releasing the resource for decoding of another of the received TBs, and / or receiving configuration information configuring a resource. In detail, the operation may include those operations related to preparing a transmission for UL transmission to the apparatus 320; those operations related to processing DL transmissions received from the apparatus 320; and those operations related to processing SL transmission to and from another apparatus 310. Processing operations related to preparing a transmission for UL transmission may include operations such as encoding, modulating, transmit beamforming and generating symbols for transmission. Processing operations related to processing DL transmissions may include operations such as receive beamforming, demodulating and decoding received symbols. Processing operations related to processing SL transmissions may include operations such as transmit / receive beamforming, modulating / demodulating and encoding / decoding symbols. Depending upon the embodiment, a DL transmission may be received by the receiver 203, possibly using receive beamforming, and the processor 210 may extract signaling from the DL transmission (e.g., by detecting and / or decoding the signaling) . An example of signaling may be a reference signal transmitted by the apparatus 320. In some implementations, the processor 210 implements the transmit beamforming and / or the receive beamforming based on the indication of beam direction, e.g., beam angle information (BAI) , received from the apparatus 320. In some implementations, the processor 210 may perform operations relating to network access (e.g., initial access) and / or downlink synchronization, such as operations relating to detecting a synchronization sequence, decoding and obtaining the system information, etc. In some implementations, the processor 210 may perform channel estimation, e.g., using a reference signal received from the apparatus 320.
[0069] Although not illustrated, the processor 210 may form part of the transmitter 201 and / or part of the receiver 203. Although not illustrated, the memory 208 may form part of the processor 210.
[0070] The processor 210, the processing components of the transmitter 201 and the processing components of the receiver 203 may each be implemented by the same or different one or more processors that are configured to execute instructions stored in a memory (e.g., in the memory 208) .
[0071] The apparatus 320 includes one or more processors 260 (only one processor 260 is illustrated to in FIG. 3) . The apparatus 320 may further include at least one transmitter 252 and at least one receiver 254 coupled to one or more antennas 256. Only one antenna 256 is illustrated to avoid congestion in the drawing. One, some, or all of the antennas 256 may alternatively be panels. The transmitter 252 and the receiver 254 may be integrated as a transceiver. The apparatus 320 may further include at least one memory 258. The apparatus 320 may further include scheduler 253. Only the transmitter 252, the receiver 254, the processor 260, the memory 258, the antenna 256 and the scheduler 253 are illustrated for simplicity, but the apparatus 320 may include one or more other components. In present disclosure, the transceiver (or transmitter 252 and / or receiver 254) may be viewed as an interface circuit.
[0072] In some implementations, the parts of the apparatus 320 may be distributed. For example, some of the modules of the apparatus 320 may be located remote from the equipment that houses the antennas 256 for the apparatus 320 (thereby also can be viewed as one or more nodes) and may be coupled to the equipment that houses the antennas 256 over a communication link (not shown) sometimes known as front haul, such as common public radio interface (CPRI) . Therefore, in some implementations, the term apparatus 320 may also refer to nodes on the network side that perform processing operations, such as determining the location of the apparatus 310, resource allocation (scheduling) , message generation, and encoding / decoding, and that are not necessarily part of the equipment that houses the antennas 256 of the apparatus 320. The nodes may also be coupled to other apparatus 320. In some embodiments, the apparatus 320 may actually be a plurality of nodes that are operating together to serve the apparatus 310, e.g., through the use of coordinated multipoint transmissions, or the use of an ORAN system, as described hereinbefore in the present application.
[0073] The processor 260 performs operations including those related to: preparing a transmission for DL transmission to the apparatus 310; processing a UL transmission received from the apparatus 310; preparing a transmission for backhaul transmission to another apparatus 320; and processing a transmission received over backhaul from another apparatus 320. Processing operations related to preparing a transmission for DL or backhaul transmission may include operations such as encoding, modulating, precoding (e.g., multiple input multiple output (MIMO) precoding) , transmit beamforming and generating symbols for transmission. Processing operations related to processing received transmissions in the UL or over backhaul may include operations such as receive beamforming, demodulating received symbols and decoding received symbols. The processor 260 may also perform operations relating to network access (e.g., initial access) and / or DL synchronization, such as generating the content of synchronization signal blocks (SSBs) , generating the system information, etc. In some implementations, the processor 260 also generates an indication of beam direction, e.g., BAI, which may be scheduled for transmission by a scheduler 253, which will be described hereinafter. In some implementations, the processor 260 implements the transmit beamforming and / or receive beamforming based on beam direction information (e.g., BAI) received from another apparatus 320. The processor 260 performs other network side processing operations described herein, such as determining the location of the apparatus 310, determining where to deploy another apparatus 320, etc. In some implementations, the processor 260 may generate signaling, e.g., to configure one or more parameters of the apparatus 310 and / or one or more parameters of another apparatus 320. Any signaling generated by the processor 260 is sent by the transmitter 252. In some implementations, the apparatus 320 implements physical layer processing. In some implementations, the apparatus 320 may implement higher layer functions, such as functions at the medium access control (MAC) or radio link control (RLC) layer in addition to a physical layer processing.
[0074] The apparatus 320 may further comprise the scheduler 253 coupled to the processor 260 or integrated in the processor 260. The scheduler 253 may be included within, or operated separately from, the apparatus 320. The scheduler 253 may schedule UL, DL, SL and / or backhaul transmissions, including issuing scheduling grants and / or configuring scheduling-free (e.g., “configured grant” ) resources.
[0075] The apparatus 320 may further include a memory 258 storing instructions used to perform operations described herein. The memory 258 may also store data used, generated or collected by the apparatus 320. For example, the memory 258 could store software instructions or modules configured to implement some or all of the functionality and / or embodiments described herein and that are executed by the processor 260.
[0076] Although not illustrated, the processor 260 may form part of the transmitter 252 and / or part of the receiver 254. Also, although not illustrated, the processor 260 may implement the scheduler 253. Although not illustrated, the memory 258 may form part of the processor 260.
[0077] The processor 260, the scheduler 253, the processing components of the transmitter 252 and the processing components of the receiver 254 may each be implemented by the same, or different one of, one or more processors that are configured to execute instructions stored in a memory, e.g., in the memory 258.
[0078] The apparatus 320 and / or apparatus 310 may include other components, but these have been omitted for the sake of clarity.
[0079] Note that “signaling, ” as used herein, may alternatively be called control signaling, control message, control information or message for simplicity. Signaling between a base station (e.g., the TRP 170a, 170b, 172) and a UE or sensing device (e.g., ED 110) , or signaling between a different UE or sensing device (e.g., between EDs 110a and 110b) may be carried in physical layer signaling (also referred to as dynamic signaling) , which is transmitted in a physical layer control channel. For DL, the physical layer signaling may be known as downlink control information (DCI) , which is transmitted in a physical downlink control channel (PDCCH) . For UL, the physical layer signaling may be known as uplink control information (UCI) , which is transmitted in a physical uplink control channel (PUCCH) . For SL, signaling between different UEs or sensing devices (e.g., between EDs 110a and 110b) may be known as SL control information (SCI) , which is transmitted in a physical sidelink control channel (PSCCH) . Signaling may be carried in a higher layer (e.g., a layer higher than the physical layer) signaling, which is transmitted in a physical layer data channel, e.g., in a physical downlink shared channel (PDSCH) for downlink signaling, in a physical uplink shared channel (PUSCH) for uplink signaling, and in a physical sidelink shared channel (PSSCH) for SL signaling. Higher layer signaling may also be called static signaling or semi-static signaling. Higher layer signaling may be radio resource control (RRC) protocol signaling or media access control -control element (MAC-CE) signaling. Signaling may be included in a combination of physical layer signaling and higher layer signaling.
[0080] It should be noted that, in the present application, “information, ” when different from “message, ” may be carried in a single message or may be carried in more than one separate message.
[0081] FIG. 4 illustrates an example of an apparatus 410. The apparatus 410 may be a communication device or an apparatus implemented in a communication device, such as ED 110 or TRPs 170a, 170b, 172. For example, the apparatus implemented in a communication device may be an integrated circuit, which, in some contexts, may be known by other colloquial names, such as chip, modem, modem chip, baseband chip or baseband processor. In some implementations, one or more integrated circuits can be packaged into a system-on-chip, a system-in-package or a multi-chip module. The apparatus 410 may comprise one or more integrated circuits or comprise one or more integrated circuits and other discrete components. In some implementations, the apparatus 410 may be a module in the ED 110 or in the apparatus 310. In some implementations, the apparatus 410 may be a module in one of the TRPs 170a, 170b, 172 or in the apparatus 320.
[0082] In an example, the apparatus 410 may include one or more processors / processor cores 411 and an interface circuit 412. The apparatus 410 may further include a memory 413. The one or more processors / processor cores 411 are configured to process signals and execute one or more communication protocols. The memory 413 is configured to store at least a part of corresponding computer program instructions and / or data. In an example, the one or more processors (or processor cores) 411 execute computer program instructions stored in the memory 413 to implement related operations (for example, inputting, outputting, receiving and transmitting) in the method embodiments disclosed herein. In some implementations, the memory 413 being configured to store the corresponding computer program instructions and / or data may mean that the memory 413 is configured to store all of the corresponding computer program instructions and / or data for execution by the one or more processors / processor cores 411. In some implementations, the memory 413 being configured to store the corresponding computer program instructions and / or data may mean that the memory 413 is configured to store a part of the corresponding computer program instructions and / or data. For example, the part of the corresponding computer program instructions and / or data may include computer program instructions and / or data that need to be currently executed by the one or more processors / processor cores 411. Thus, the memory 413 may store different parts of computer program instructions and / or data for a plurality times for the one or more processors (or processor cores) 411 to perform related operations in the method embodiments disclosed herein. As a communication interface, the interface circuit 412 is configured to implement communication with another component. For example, the interface circuit 412 may communicate a signal with another apparatus / system, such as a radio frequency processing apparatus or a processor system. Optionally, to reduce a load of the processors (or processor cores) , a baseband signal processing circuit 414 may also be disposed to implement processing of at least a part of baseband signals, including signal demodulation, modulation, encoding, decoding, or the like.
[0083] The apparatus 410 may, in some scenarios, be the processor 210 (or the processor 260) in the apparatus 310 (or in the apparatus 320) or may be included in the processor 210 (or the processor 260) in the apparatus 310 (or the apparatus 320) in some scenarios. The apparatus 410 may be, or may include, a baseband chip. In some implementations, the apparatus 410 may be independently packaged into a chip. In some implementations, the apparatus 310 (or the apparatus 320) includes different types of chips. The apparatus 410 may be packaged into a processor chip (for example, an SoC chip or an SIP chip) with the different types of chips. In some implementations, the apparatus 410 may be packaged into a chip with some or all of circuits of a radio frequency processing system that may further included in the apparatus 310 (or the apparatus 320) .
[0084] FIG. 5 illustrates an example apparatus 510. The apparatus 510 may include corresponding modules or units configured to implement methods and / or embodiments described herein. In some implementations, the apparatus 510 includes a processing unit 512 and a communication unit 513. Optionally, the apparatus 510 may further include a storage unit 511 configured to store apparatus program code (or instructions) and / or data.
[0085] The apparatus 510 may be an ED side apparatus, for example, an ED or a module in an ED, or a circuit or a chip responsible for a communication function in an ED. In some implementations, the apparatus 510 may be implemented as the apparatus 310. Accordingly, the processing unit 512 may be implemented as the processor 210 (see FIG. 3) , the communication unit 513 may be implemented as the transmitter 201 and / or the receiver 203 (see FIG. 3) and the storage unit 511 may be implemented as the memory 208 (see FIG. 3) .
[0086] The apparatus 510 may be a base station side apparatus, for example, a base station or a module in a base station, or a circuit or a chip responsible for a communication function in a base station. In some implementations, the apparatus 510 may be implemented as the apparatus 320. Accordingly, the processing unit 512 may be implemented as the processor 260 (the scheduler 253 may also be included, see FIG. 3) , the communication unit 513 may be implemented as the transmitter 252 and / or the receiver 254 (see FIG. 3) and the storage unit 511 may be implemented as the memory 258.
[0087] In some implementations, when the apparatus 510 is an ED 110 or a module in an ED 110, a function of the apparatus 510 may be implemented by one or more processors. Specifically, the processor may include a modem chip or a system on chip (SoC) chip or an SIP chip that includes a modem core. A function of the communication unit 513 may be implemented by a transceiver circuit.
[0088] In some implementations, when the apparatus 510 is a circuit or a chip that is responsible for a communication function in an ED 110, for example, a modem chip, a system on chip (SoC) chip or an SIP chip that includes a modem core, a function of the processing unit 512 may be implemented by a circuit system that is in the chip and that includes one or more processors or processor cores. A function of the communication unit 513 may be implemented by an interface circuit or a data transceiver circuit on the foregoing chip.
[0089] It may be understood that division into the units in the foregoing apparatus is merely logical function division. Each function may correspond to one functional unit or two or more functions may be integrated into one functional unit. In actual implementation, all or some of the units may be integrated into one physical entity or may be distributed in different physical entities. In addition, the foregoing functional units may be implemented in a form of hardware, may be implemented in a form of software or may be implemented in a form of a combination of hardware and software. Whether a function is performed in a form of hardware or software depends on particular applications and design constraint conditions of the technical solutions. A person skilled in the art may use different methods to implement the described functions for each particular application, but it should not be considered that the implementation goes beyond the scope of this application.
[0090] In an example, a functional unit in any one of the foregoing apparatuses may be configured as one or more integrated circuits for implementing the foregoing methods, for example, one or more application-specific integrated circuits (application-specific integrated circuits, ASICs) , one or more central processing units (central processing units, CPUs) , one or more microprocessors (microcontroller units, MCUs) , one or more digital signal processors (digital signal processors, DSP) , one or more field programmable gate arrays (field programmable gate arrays, FPGAs) , or a combination of at least two of these integrated circuit forms.
[0091] In an example, the storage unit 511 may include a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an electrically erasable programmable memory, and / or a register.
[0092] A processor, a processor system, an application processor, a baseband processor, a processor circuit, or a processor core may be collectively referred to as a processor. The processor may include one or a combination of a central processing unit (CPU) , a digital signal processor (DSP) , a microprocessor (microprocessor unit, MPU) , a microcontroller (microcontroller unit, MCU) , a graphics processing unit (GPU) , a field programmable gate array (FPGA) , an artificial intelligence processor (AI processor) , or a neural network processing unit (NPU) .
[0093] A memory or a storage unit may include one or more of the following storage media: a random access memory (RAM) ; a static random access memory (static RAM, SRAM) ; a dynamic random access memory (dynamic RAM, DRAM) ; a phase-change memory (PCM) ; a resistive random access memory (resistive RAM, ReRAM) ; a magnetoresistive random access memory (magnetoresistive RAM, MRAM) ; a ferroelectric random access memory (ferroelectric RAM, FRAM) ; a cache; a register; a read-only memory (ROM) ; a flash memory (flash memory) ; an erasable programmable read-only memory (erasable programmable ROM, EPROM) ; a hard disk; and the like. In an example, computer program instructions used to execute embodiments may be stored in a non-volatile memory, for example, at least a part of a memory or storage unit (for example, one or more of a ROM, a flash memory, an EPROM, or a hard disk) . When a terminal runs, a part or all of corresponding computer program instructions may be loaded to a memory that has a higher transmission speed with the processor, for example, at least a part of a memory or a storage unit (for example, one or more of a RAM, an SRAM, a DRAM, a PCM, a RERAM, an MRAM, a FRAM, a cache, or a register) , so that the processor executes the computer program instructions to perform the steps in the method embodiments disclosed herein.
[0094] An air interface generally includes a number of components and associated parameters that collectively specify how a transmission is to be sent and / or received over a wireless communications link between two or more communicating devices. For example, an air interface may include one or more components defining the waveform (s) , frame structure (s) , multiple access scheme (s) , protocol (s) , coding scheme (s) and / or modulation scheme (s) for conveying information (e.g., data) over a wireless communications link. The wireless communications link may support a link between a radio access network and user equipment (e.g., a “Uu” link) , and / or the wireless communications link may support a link between device and device, such as between two user equipments (e.g., a “sidelink” ) , and / or the wireless communications link may support a link between a non-terrestrial (NT) -communication network and user equipment (UE) . The following are some examples for the above components.
[0095] ο A waveform component may specify a shape and a form of a signal being transmitted. Waveform options may include orthogonal multiple access waveforms and non-orthogonal multiple access waveforms. Non-limiting examples of such waveform options include Orthogonal Frequency Division Multiplexing (OFDM) , Direct Fourier Transform spread OFDM (DFT-OFDM) , Filtered OFDM (f-OFDM) , Time windowing OFDM, Filter Bank Multicarrier (FBMC) , Universal Filtered Multicarrier (UFMC) , Generalized Frequency Division Multiplexing (GFDM) , Wavelet Packet Modulation (WPM) , Faster Than Nyquist (FTN) Waveform and low Peak to Average Power Ratio Waveform (low PAPR WF) .
[0096] ο A frame structure component may specify a configuration of a frame or group of frames. The frame structure component may indicate one or more of a time, frequency, pilot signature, code, subcarrier spacing, cyclic prefix length or other parameter of the frame or group of frames. More details of frame structure will be discussed hereinafter.
[0097] ο A multiple access scheme component may specify multiple access technique options, including technologies defining how communicating devices share a common physical channel, such as: TDMA; FDMA; CDMA; space division multiple access (SDMA) ; OFDMA; SC-FDMA; Low Density Signature Multicarrier CDMA (LDS-MC-CDMA) ; Non-Orthogonal Multiple Access (NOMA) ; Pattern Division Multiple Access (PDMA) ; Lattice Partition Multiple Access (LPMA) ; Resource Spread Multiple Access (RSMA) ; and Sparse Code Multiple Access (SCMA) . Furthermore, multiple access technique options may include: scheduled access vs. non-scheduled access, also known as grant-free access; non-orthogonal multiple access vs. orthogonal multiple access, e.g., via a dedicated channel resource (e.g., no sharing between multiple communicating devices) ; contention-based shared channel resources vs. non-contention-based shared channel resources; and cognitive radio-based access.
[0098] ο A hybrid automatic repeat request (HARQ) protocol component may specify how a transmission and / or a re-transmission is to be made. Non-limiting examples of transmission and / or re-transmission mechanism options include those that specify a scheduled data pipe size, a signaling mechanism for transmission and / or re-transmission and a re-transmission mechanism.
[0099] ο A coding and modulation component may specify how information being transmitted may be encoded / decoded and modulated / demodulated for transmission / reception purposes. Coding may refer to methods of error detection and forward error correction. Non-limiting examples of coding options include turbo trellis codes, turbo product codes, fountain codes, low-density parity check codes and polar codes. Modulation may refer, simply, to the constellation (including, for example, the modulation technique and order) , or more specifically to various types of advanced modulation methods such as hierarchical modulation and low PAPR modulation.
[0100] In some embodiments, the air interface may be a “one-size-fits-all concept. ” For example, the components within the air interface cannot be changed or adapted once the air interface is defined. In some implementations, only limited parameters or modes of an air interface, such as a cyclic prefix (CP) length or a MIMO mode, can be configured. In some embodiments, an air interface design may provide a unified or flexible framework to support frequencies below known 6 GHz bands and frequencies beyond the 6 GHz bands (e.g., mmWave bands) for both licensed and unlicensed access. As an example, flexibility of a configurable air interface provided by a scalable numerology and symbol duration may allow for transmission parameter optimization for different spectrum bands and for different services / devices. As another example, a unified air interface may be self-contained in a frequency domain and a frequency domain self-contained design may support more flexible RAN slicing through channel resource sharing between different services in both frequency and time.
[0101] A frame structure is a feature of the wireless communication physical layer that defines a time domain signal transmission structure, e.g., to allow for timing reference and timing alignment of basic time domain transmission units. Wireless communication between communicating devices may occur on time-frequency resources governed by a frame structure. The frame structure may, sometimes, instead be called a radio frame structure.
[0102] Depending upon the frame structure and / or configuration of frames in the frame structure, frequency division duplex (FDD) and / or time-division duplex (TDD) and / or full duplex (FD) communication may be possible. FDD communication is when transmissions in different directions (e.g., uplink vs. downlink) occur in different frequency bands. TDD communication is when transmissions in different directions (e.g., uplink vs. downlink) occur over different time durations. FD communication is when transmission and reception occurs on the same time-frequency resource, i.e., a device can both transmit and receive on the same frequency resource concurrently in time.
[0103] One example of a frame structure is a frame structure in long-term evolution (LTE) cellular systems, having the following specifications: each frame is 10 ms in duration; each frame has 10 subframes, which subframes are each 1 ms in duration; each subframe includes two slots, each of which slots is 0.5 ms in duration; each slot is for the transmission of seven OFDM symbols (assuming normal CP) ; each OFDM symbol has a symbol duration and a particular bandwidth (or partial bandwidth or bandwidth partition) related to the number of subcarriers and subcarrier spacing; the frame structure is based on OFDM waveform parameters such as subcarrier spacing and CP length (where the CP has a fixed length or limited length options) ; and the switching gap between uplink and downlink in TDD has to be the integer time of OFDM symbol duration.
[0104] Another example of a frame structure is a frame structure in new radio (NR) having the following specifications: multiple subcarrier spacings are supported, each subcarrier spacing corresponding to a respective numerology; the frame structure depends on the numerology, but the frame length is set at 10 ms and each frame consists of ten subframes, each subframe of 1 ms duration; a slot is defined as 14 OFDM symbols; and slot length depends upon the numerology. For example, the NR frame structure for normal CP 15 kHz subcarrier spacing ( “numerology 1” ) and the NR frame structure for normal CP 30 kHz subcarrier spacing ( “numerology 2” ) are different. For 15 kHz subcarrier spacing, the slot length is 1 ms and, for 30 kHz subcarrier spacing, the slot length is 0.5 ms. The NR frame structure may have more flexibility than the LTE frame structure.
[0105] Another example of a frame structure is an example flexible frame structure, e.g., for use in a 6G network or a later network. In a flexible frame structure, a symbol block may be defined as the minimum duration of time that may be scheduled in the flexible frame structure. A symbol block may be a unit of transmission having an optional redundancy portion (e.g., CP portion) and an information (e.g., data) portion. An OFDM symbol is an example of a symbol block. A symbol block may alternatively be called a symbol. Embodiments of flexible frame structures include different parameters that may be configurable, e.g., frame length, subframe length, symbol block length, etc. A non-exhaustive list of possible configurable parameters, in some embodiments of a flexible frame structure, includes:
[0106] 1) A frame length parameter: The frame length need not be limited to 10 ms and the frame length may be configurable and change over time. In some embodiments, each frame includes one or multiple downlink synchronization channels and / or one or multiple downlink broadcast channels and each synchronization channel and / or broadcast channel may be transmitted in a different direction by different beamforming. The frame length may be more than one possible value and configured based on the application scenario. For example, autonomous vehicles may require relatively fast initial access, in which case the frame length may be set as 5 ms for autonomous vehicle applications. As another example, smart meters on houses may not require fast initial access, in which case the frame length may be set as 20 ms for smart meter applications.
[0107] 2) A subframe duration parameter: A subframe might or might not be defined in the flexible frame structure, depending upon the implementation. For example, a frame may be defined to include slots, but no subframes. In frames in which a subframe is defined, e.g., for time domain alignment, then the duration of the subframe may be configurable. For example, a subframe may be configured to have a length of 0.1 ms or 0.2 ms or 0.5 ms or 1 ms or 2 ms or 5 ms, etc. In some embodiments, if a subframe is not needed in a particular scenario, then the subframe length may be defined to be the same as the frame length or not defined.
[0108] 3) A slot configuration parameter: A slot might or might not be defined in the flexible frame structure, depending upon the implementation. In frames in which a slot is defined, then the definition of a slot (e.g., in time duration and / or in number of symbol blocks) may be configurable. In one embodiment, the slot configuration is common to all UEs or a group of UEs. For this case, the slot configuration information may be transmitted to the UEs in a broadcast channel or common (or group) control channel (s) . In other embodiments, the slot configuration may be UE specific, in which case the slot configuration information may be transmitted in a UE-specific control channel. In some embodiments, the slot configuration signaling can be transmitted together with frame configuration signaling and / or subframe configuration signaling. In other embodiments, the slot configuration may be transmitted independently from the frame configuration signaling and / or subframe configuration signaling. In general, the slot configuration may be system common, base station common, UE group common or UE specific.
[0109] 4) A subcarrier spacing (SCS) parameter: The SCS parameter is one parameter of scalable numerology that may allow the SCS to possibly range from 15 KHz to 480 KHz. The SCS may vary with the frequency of the spectrum and / or maximum UE speed to minimize the impact of Doppler shift and phase noise. In some examples, there may be separate transmission and reception frames and the SCS of symbols in the reception frame structure may be configured independently from the SCS of symbols in the transmission frame structure. The SCS in a reception frame may be different from the SCS in a transmission frame. In some examples, the SCS of each transmission frame may be half the SCS of each reception frame. If the SCS between a reception frame and a transmission frame is different, the difference does not necessarily have to scale by a factor of two, e.g., if more flexible symbol durations are implemented using inverse discrete Fourier transform (IDFT) instead of fast Fourier transform (FFT) . Additional examples of frame structures can be used with different SCSs.
[0110] 5) A parameter indicative of a flexible transmission duration of a basic transmission unit: The basic transmission unit may be a symbol block (alternatively called a symbol) , which, in general, includes a redundancy portion (referred to as the CP) and an information (e.g., data) portion. In some embodiments, the CP may be omitted from the symbol block. The CP length may be flexible and configurable. The CP length may be fixed within a frame or flexible within a frame and the CP length may possibly change from one frame to another, or from one group of frames to another group of frames, or from one subframe to another subframe, or from one slot to another slot, or dynamically from one scheduling to another scheduling. The information (e.g., data) portion may be flexible and configurable. Another possible parameter relating to a symbol block that may be defined is ratio of CP duration to information (e.g., data) duration. In some embodiments, the symbol block length may be adjusted according to: a channel condition (e.g., multi-path delay, Doppler) ; and / or a latency requirement; and / or an available time duration. As another example, a symbol block length may be adjusted to fit an available time duration in the frame.
[0111] 6) A Flexible switch gap parameter: A frame may include both a downlink portion, for downlink transmissions from a base station, and an uplink portion, for uplink transmissions from UEs. A gap may be present between each uplink and downlink portion, which gap is referred to as a switching gap. The switching gap length (duration) may be configurable. A switching gap duration may be fixed within a frame or flexible within a frame and a switching gap duration may possibly change from one frame to another, or from one group of frames to another group of frames, or from one subframe to another subframe, or from one slot to another slot, or dynamically from one scheduling to another scheduling.
[0112] A device, such as a base station, may provide coverage over a cell. Wireless communication with the device may occur over one or more carrier frequencies. A carrier frequency will be referred to as a carrier. A carrier may alternatively be called a component carrier (CC) . A carrier may be characterized by its bandwidth and a reference frequency, e.g., the center frequency of the carrier, the lowest frequency of the carrier or the highest frequency of the carrier. A carrier may be on a licensed spectrum or an unlicensed spectrum. Wireless communication with the device may also, or instead, occur over one or more bandwidth parts (BWPs) . For example, a carrier may have one or more BWPs. More generally, wireless communication with the device may occur over spectrum. The spectrum may comprise one or more carriers and / or one or more BWPs.
[0113] A cell may include one or multiple downlink resources and, optionally, one or multiple uplink resources. A cell may include one or multiple uplink resources and, optionally, one or multiple downlink resources. A cell may include both one or multiple downlink resources and one or multiple uplink resources. As an example, a cell might only include one downlink carrier / BWP, or only include one uplink carrier / BWP, or include multiple downlink carriers / BWPs, or include multiple uplink carriers / BWPs, or include one downlink carrier / BWP and one uplink carrier / BWP, or include one downlink carrier / BWP and multiple uplink carriers / BWPs, or include multiple downlink carriers / BWPs and one uplink carrier / BWP, or include multiple downlink carriers / BWPs and multiple uplink carriers / BWPs. In some embodiments, a cell may, instead or additionally, include one or multiple sidelink resources, including sidelink transmitting and receiving resources.
[0114] A BWP is a set of contiguous or non-contiguous frequency subcarriers on a carrier, or a set of contiguous or non-contiguous frequency subcarriers on multiple carriers, or a set of non-contiguous or contiguous frequency subcarriers, which may have one or more carriers.
[0115] In some embodiments, a carrier may have one or more BWPs, e.g., a carrier may have a bandwidth of 20 MHz and consist of one BWP or a carrier may have a bandwidth of 80 MHz and consist of two adjacent contiguous BWPs, etc. In other embodiments, a BWP may have one or more carriers, e.g., a BWP may have a bandwidth of 40 MHz and consist of two adjacent contiguous carriers, where each carrier has a bandwidth of 20 MHz. In some embodiments, a BWP may comprise non-contiguous spectrum resources, which consists of non-contiguous multiple carriers, where the first carrier of the non-contiguous multiple carriers may be in mmW band, the second carrier may be in a low band (such as 2 GHz band) , the third carrier (if it exists) may be in THz band and the fourth carrier (if it exists) may be in visible light band. Resources in one carrier which belong to the BWP may be contiguous or non-contiguous. In some embodiments, a BWP has non-contiguous spectrum resources on one carrier.
[0116] Wireless communication may occur over an occupied bandwidth. The occupied bandwidth may be defined as the width of a frequency band such that, below the lower and above the upper frequency limits, the mean powers emitted are each equal to a specified percentage, β / 2, of the total mean transmitted power, for example, the value of β / 2 is taken as 0.5%.
[0117] The carrier, the BWP or the occupied bandwidth may be signaled by a network device (e.g., by a base station) dynamically, e.g., in physical layer control signaling such as the known DCI, or semi-statically, e.g., in radio resource control (RRC) signaling or in signaling in the medium access control (MAC) layer, or be predefined based on the application scenario; or be determined by the UE as a function of other parameters that are known by the UE, or may be fixed, e.g., by a standard.
[0118] UE position information is often used in cellular communication networks to improve various performance metrics for the network. Such performance metrics may, for example, include capacity, agility and efficiency. The improvement may be achieved when elements of the network exploit the position, the behavior, the mobility pattern, etc., of the UE in the context of a priori information describing a wireless environment in which the UE is operating.
[0119] A sensing system may be used to help gather UE pose information, including UE location in a global coordinate system, UE velocity and direction of movement in the global coordinate system, orientation information and the information about the wireless environment. “Location” is also known as “position” and these two terms may be used interchangeably herein. Examples of well-known sensing systems include RADAR (Radio Detection and Ranging) and LIDAR (Light Detection and Ranging) . While the sensing system can be separate from the communication system, it could be advantageous to gather the information using an integrated system, which reduces the hardware (and cost) in the system as well as the time, frequency or spatial resources needed to perform both functionalities. However, using the communication system hardware to perform sensing of UE pose and environment information is a highly challenging and open problem. The difficulty of the problem relates to factors such as the limited resolution of the communication system, the dynamicity of the environment, and the huge number of objects whose electromagnetic properties and position are to be estimated.
[0120] Accordingly, integrated sensing and communication (also known as integrated communication and sensing) is a desirable feature in existing and future communication systems and it is desirable to provide improvements for practical implementations of integrated sensing and communication.
[0121] Any or all of the EDs 110 and BS 170 may be sensing nodes in the system 100. Sensing nodes are network entities that perform sensing by transmitting and receiving sensing signals. Some sensing nodes are communication equipment that perform both communications and sensing. However, it is possible that some sensing nodes do not perform communications and are, instead, dedicated to sensing.
[0122] The network illustrated in FIG. 6 differs from the network illustrated in FIG. 2 in the addition of a sensing agent 174, which is an example of a sensing node that is dedicated to sensing. Unlike the EDs 110 and BS 170, the sensing agent 174 does not transmit or receive communication signals. However, the sensing agent 174 may communicate configuration information, sensing information, signaling information or other information within the communication system 100. The sensing agent 174 may be in communication with the core network 130 to communicate information with the rest of the communication system 100. By way of example, the sensing agent 174 may determine the location of the ED 110a, and transmit this information to the base station 170a via the core network 130. Although only one sensing agent 174 is shown in FIG. 6, any number of sensing agents may be implemented in the communication system 100. In some embodiments, one or more sensing agents may be implemented at one or more of the RANs 120.
[0123] A sensing node may combine sensing-based techniques with reference signal-based techniques to enhance UE pose determination. This type of sensing node may also be known as a sensing management function (SMF) . In some networks, the SMF may also be known as a location management function (LMF) . The SMF may be implemented as a physically independent entity located at the core network 130 with connection to the multiple BSs 170. In other aspects of the present application, the SMF may be implemented as a logical entity co-located inside a BS 170 through logic carried out by the processor 260.
[0124] As shown in FIG. 7, an SMF 176, when implemented as a physically independent entity, includes at least one processor 290, at least one transmitter 282, at least one receiver 284, one or more antennas 286 and at least one memory 288. A transceiver, not shown, may be used instead of the transmitter 282 and the receiver 284. A scheduler 283 may be coupled to the processor 290. The scheduler 283 may be included within or operated separately from the SMF 176. The processor 290 implements various processing operations of the SMF 176, such as signal coding, data processing, power control, input / output processing or any other functionality. The processor 290 can also be configured to implement some or all of the functionality and / or embodiments described in more detail above. Each processor 290 includes any suitable processing or computing device configured to perform one or more operations. Each processor 290 could, for example, include a microprocessor, microcontroller, digital signal processor, field programmable gate array or application specific integrated circuit.
[0125] A reference signal-based pose determination technique belongs to an “active” pose estimation paradigm. In an active pose estimation paradigm, the enquirer of pose information (e.g., the UE) takes part in process of determining the pose of the enquirer. The enquirer may transmit or receive (or both) a signal specific to pose determination process. Positioning techniques based on a global navigation satellite system (GNSS) such as the known Global Positioning System (GPS) are other examples of the active pose estimation paradigm.
[0126] In contrast, a sensing-based technique, based on radar for example, may be considered as belonging to a “passive” pose determination paradigm. In a passive pose determination paradigm, the target is oblivious to the pose determination process.
[0127] By integrating sensing and communications in one system, the system need not operate according to only a single paradigm. Thus, the combination of sensing-based techniques and reference signal-based techniques can yield enhanced pose determination.
[0128] The enhanced pose determination may, for example, include obtaining UE channel sub-space information, which is particularly useful for UE channel reconstruction at the sensing node, especially for a beam-based operation and communication. The UE channel sub-space is a subset of the entire algebraic space, defined over the spatial domain, in which the entire channel from the TP to the UE lies. Accordingly, the UE channel sub-space defines the TP-to-UE channel with very high accuracy. The signals transmitted over other sub-spaces result in a negligible contribution to the UE channel. Knowledge of the UE channel sub-space helps to reduce the effort needed for channel measurement at the UE and channel reconstruction at the network-side. Therefore, the combination of sensing-based techniques and reference signal-based techniques may enable the UE channel reconstruction with much less overhead as compared to traditional methods. Sub-space information can also facilitate sub-space-based sensing to reduce sensing complexity and improve sensing accuracy.
[0129] In some embodiments of integrated sensing and communication, a same radio access technology (RAT) is used for sensing and communication. This avoids the need to multiplex two different RATs under one carrier spectrum, or necessitating two different carrier spectrums for the two different RATs.
[0130] In embodiments that integrate sensing and communication under one RAT, a first set of channels may be used to transmit a sensing signal and a second set of channels may be used to transmit a communications signal. In some embodiments, each channel in the first set of channels and each channel in the second set of channels is a logical channel, a transport channel or a physical channel.
[0131] At the physical layer, communication and sensing may be performed via separate physical channels. For example, a first physical downlink shared channel PDSCH-C is defined for data communication, while a second physical downlink shared channel PDSCH-Sis defined for sensing. Similarly, separate physical uplink shared channels (PUSCH) , PUSCH-C and PUSCH-S, could be defined for uplink communication and sensing.
[0132] In another example, the same PDSCH and PUSCH could be also used for both communication and sensing, with separate logical layer channels and / or transport layer channels defined for communication and sensing. Note also that control channel (s) and data channel (s) for sensing can have the same or different channel structure (format) , occupy same or different frequency bands or bandwidth parts.
[0133] In a further example, a common physical downlink control channel (PDCCH) and a common physical uplink control channel (PUCCH) may be used to carry control information for both sensing and communication. Alternatively, separate physical layer control channels may be used to carry separate control information for communication and sensing. For example, PUCCH-S and PUCCH-C could be used for uplink control for sensing and communication respectively and PDCCH-S and PDCCH-C for downlink control for sensing and communication respectively.
[0134] Different combinations of shared and dedicated channels for sensing and communication, at each of the physical, transport, and logical layers, are possible.
[0135] The term RADAR originates from the phrase Radio Detection and Ranging; however, expressions with different forms of capitalization (e.g., Radar and radar) are equally valid and now more common. Radar is typically used for detecting a presence and a location of an object. A radar system radiates radio frequency energy and receives echoes of the energy reflected from one or more targets. The system determines the pose of a given target based on the echoes returned from the given target. The radiated energy can be in the form of an energy pulse or a continuous wave, which can be expressed or defined by a particular waveform. Examples of waveforms used in radar include frequency modulated continuous wave (FMCW) and ultra-wideband (UWB) waveforms.
[0136] Radar systems can be monostatic, bi-static or multi-static. In a monostatic radar system, the radar signal transmitter and receiver are co-located, such as being integrated in a transceiver. In a bi-static radar system, the transmitter and receiver are spatially separated, and the distance of separation is comparable to, or larger than, the expected target distance (often referred to as the range) . In a multi-static radar system, two or more radar components are spatially diverse but with a shared area of coverage. A multi-static radar is also referred to as a multisite or netted radar.
[0137] Terrestrial radar applications encounter challenges such as multipath propagation and shadowing impairments. Another challenge is the problem of identifiability because terrestrial targets have similar physical attributes. Integrating sensing into a communication system is likely to suffer from these same challenges, and more.
[0138] Communication nodes can be either half-duplex or full-duplex. A half-duplex node cannot both transmit and receive using the same physical resources (time, frequency, etc. ) ; conversely, a full-duplex node can transmit and receive using the same physical resources. Existing commercial wireless communications networks (1G through 6G) are all half-duplex. Even if full-duplex communications networks are used in the future, it is expected that at least some of the nodes in the network will still be half-duplex nodes because half-duplex devices are less complex, and have lower cost and lower power consumption. In particular, full-duplex implementation is more challenging at higher frequencies (e.g., in the millimeter wave bands) and very challenging for small and low-cost devices, such as femtocell base stations and UEs.
[0139] The limitation of half-duplex nodes in the communications network presents further challenges toward integrating sensing and communications into the devices and systems of the communications network. For example, both half-duplex and full-duplex nodes can perform bi-static or multi-static sensing, but monostatic sensing typically requires the sensing node have full-duplex capability. A half-duplex node may perform monostatic sensing with certain limitations, such as in a pulsed radar with a specific duty cycle and ranging capability.
[0140] Properties of a sensing signal, or a signal used for both sensing and communication, include the waveform of the signal and the frame structure of the signal. The frame structure defines the time-domain boundaries of the signal. The waveform describes the shape of the signal as a function of time and frequency. Examples of waveforms that can be used for a sensing signal include ultra-wide band (UWB) pulse, Frequency-Modulated Continuous Wave (FMCW) or “chirp” , orthogonal frequency-division multiplexing (OFDM) , cyclic prefix (CP) -OFDM, and Discrete Fourier Transform spread (DFT-s) -OFDM.
[0141] In an embodiment, the sensing signal is a linear chirp signal with bandwidth B and time duration T. Such a linear chirp signal is generally known from its use in FMCW radar systems. A linear chirp signal is defined by an increase in frequency from an initial frequency, fchirp0, at an initial time, tchirp0, to a final frequency, fchirp1, at a final time, tchirp1 where the relation between the frequency (f) and time (t) can be expressed as a linear relation of f-fchirp0=α (t-tchirp0) , where is defined as the chirp slope. The bandwidth of the linear chirp signal may be defined as B=fchirp1-fchirp0 and the time duration of the linear chirp signal may be defined as T=tchirp1-tchirp0. Such linear chirp signal can be presented as in the baseband representation.
[0142] Precoding, as used herein, may refer to any coding operation (s) or modulation (s) that transform an input signal into an output signal. Precoding may be performed in different domains and typically transforms the input signal in a first domain to an output signal in a second domain. Precoding may include linear operations.
[0143] A terrestrial communication system may also be referred to as a land-based or ground-based communication system, although a terrestrial communication system can also, or instead, be implemented on or in water. A wireless communications system may support communications between a UE and non-terrestrial devices, which is also called as a non-terrestrial communication system. The non-terrestrial communication system may bridge coverage gaps in underserved areas by extending the coverage of cellular networks through the use of non-terrestrial nodes, which will be key to establishing global, seamless coverage and providing mobile broadband services to unserved / underserved regions. In the current case, it is hardly possible to implement terrestrial access-points / base-stations infrastructure in areas like oceans, mountains, forests, or other remote areas.
[0144] The terrestrial communication system may be a wireless communications system using 5G technology and / or later generation wireless technology (e.g., 6G or later) . In some examples, the terrestrial communication system may also accommodate some legacy wireless technologies (e.g., 3G or 4G wireless technology) . The non-terrestrial communication system may be a communications system using satellite constellations, like conventional Geo-Stationary Orbit (GEO) satellites, which utilize broadcast public / popular contents to a local server. The non-terrestrial communication system may be a communications system using low earth orbit (LEO) satellites, which are known to establish a better balance between large coverage area and propagation path-loss / delay. The non-terrestrial communication system may be a communications system using stabilized satellites in very low earth orbits (VLEO) technologies, thereby substantially reducing the costs for launching satellites to lower orbits. The non-terrestrial communication system may be a communications system using high altitude platforms (HAPs) , which are known to provide a low path-loss air interface for the users with limited power budget. The non-terrestrial communication system may be a communications system using Unmanned Aerial Vehicles (UAVs) (or unmanned aerial system, “UAS” ) achieving a dense deployment, since their coverage can be limited to a local area, such as airborne, balloon, quadcopter, drones, etc. In some examples, GEO satellites, LEO satellites, UAVs, HAPs and VLEOs may be horizontal and two-dimensional. In some examples, UAVs, HAPs and VLEOs may be coupled to integrate satellite communications to cellular networks. Emerging 3D vertical networks consist of many moving (other than geostationary satellites) and high altitude access points such as UAVs, HAPs and VLEOs.
[0145] One possible scenario is that T-TRPs 170 are communicating with NT-TRPs 172 that are part of a satellite constellation, as shown in an example network 800 illustrated in FIG. 8. A satellite constellation comprises a plurality of satellites in satellite orbits that are arranged such that Earth is provided with wireless coverage from the satellites. Each satellite orbit may have a plurality of satellites therein. The T-TRPs 170 may be connected to the core network 130 through terrestrial ( “TN” ) gateways 802, while the NT-TRPs 172, in the satellite constellations, may be connected to the core network 130 through dedicated, non-terrestrial ( “NTN” ) gateways 804. Devices, such as UEs, may connect and communicate with a T-TRP 170 or with an NT-TRP 172 depending on the conditions of traffic load, radio link quality, congestion, and so on.
[0146] Another possible scenario may be envisioned wherein the satellite constellation effectively acts as the gateway for the T-TRPs 170 on the ground, as shown in an example network 900 illustrated in FIG. 9. The NT-TRPs 172 in the satellite constellation communicate with the core network 130 through NTN gateways 804 located on the ground using a wireless link, while the NTN gateways 804 on the ground may use a wired link (e.g., a fiber optic link) to communicate with the core network 130. The T-TRPs 170 communicate with satellites using a wireless link and satellites communicate between each-other using free space optical links (using, e.g., lasers) . Devices, such as UEs, may connect and communicate with a T-TRP 170 or with an NT-TRP 172, depending on the conditions of traffic load, radio link quality, congestion, and so on.
[0147] Another possible scenario may be envisioned where the NT-TRPs 172 communicate with the T-TRPs 170 through the core network 130, as shown in an example network 1000 illustrated in FIG. 10. The NT-TRPs 172 may first communicate with dedicated non-terrestrial gateways 804, which then communicate with the core network 130. The core network 130 may then relay information from the NT-TRPs 172 to the T-TRPs 170 via dedicated terrestrial gateways 802. Devices, such as UEs, may connect and communicate with a T-TRP 170 or with an NT-TRP 172, depending on the conditions of traffic load, radio link quality, congestion, and so on.
[0148] In the scenarios above, a link between a UE and a NT-TRP 172 may be called a service link and links between the NT-TRPs 172 and the NTN gateway 804 may be called feeder links. In addition, a link between two NT-TRPs 172 may be called an inter-satellite link (ISL) (not shown in FIG. 8, 9 or 10) . Each NT-TRP 172 may be associated with one or more NTN gateways 804.
[0149] Multiple-input-multiple-output technology (sometimes simply referred to as “MIMO” ) allows an antenna array having multiple antennas to perform enhanced signal transmissions and receptions, which can result in higher data transmission rates. The ED 110 and the T-TRP 170 and / or the NT-TRP 172 may use MIMO to communicate over physical layer wireless resources. MIMO utilizes multiple antennas at a transmit apparatus and / or receive apparatus to transmit and / or receive data in a same physical layer resource block over multiple parallel wireless signals. It follows that multiple antennas may be utilized at the receiver. MIMO may involve beamforming parallel wireless signals for reliable multipath transmission of data in the resource block. MIMO may involve bonding parallel wireless signals that transport different data, thereby effectively increasing the data rate of the data carried in a resource block.
[0150] In recent years, a MIMO wireless communication system with the T-TRP 170 and / or the NT-TRP 172 configured with a large number of antennas (known as a large-scale MIMO or massive MIMO, for example) has gained wide attention from academia and industry. In the large-scale MIMO system, the T-TRP 170 and / or the NT-TRP 172, are generally configured with more than ten antennas (such as 128 antennas or 256 antennas) and serve dozens of the ED 110 (such as 40 devices) . By having a large number of antennas, the T-TRP 170 and / or the NT-TRP 172 can greatly increase the degree of spatial freedom of wireless communications, improve transmission rates, spectrum efficiency and power efficiency and minimize or largely eliminate interference between cells. Using the degree of spatial freedom provided by the large number of antennas, the T-TRP 170 and / or the NT-TRP 172 of each cell can communicate with many ED 110 in the cell on a same frequency resource at a same time (that is, on a same time-frequency resource) , thus greatly increasing the spectrum efficiency of the system. By having a large number of antennas, the T-TRP 170 and / or the NT-TRP 172 also enable each user to have better spatial directivity for uplink and downlink transmission. This can further result in a reduction of transmission power at one or more of the T-TRP 170, the NT-TRP 172 and the ED 110, thus improving overall power efficiency in the system.
[0151] MIMO technology may include single-user MIMO (SU-MIMO) , where signals on multiple spatial layers are transmitted to a same ED 110, and multiple-user MIMO (MU-MIMO) , where multiple spatial layers are transmitted to multiple EDs 110.
[0152] A MIMO system may include a receive apparatus (ED 110 for a downlink transmission, the T-TRP 170 and / or the NT-TRP 172 for an uplink transmission, for example) connected to one or more receive (RX) antennas, a transmit apparatus (the T-TRP 170 and / or the NT-TRP 172 for a downlink transmission, or ED 110 for an uplink transmission, for example) connected to one or more transmit (TX) antennas. For instance, a plurality of RX antennas may form an antenna array in which the plurality of RX antennas are arranged in line at even intervals, which may be known as a uniform linear array (ULA) .
[0153] FIG. 11 illustrates an example of a channel model of a MIMO system. A transmit apparatus 1102 is connected to four TX antennas, labelled x1, x2, x3 and x4. A receive apparatus 1104 is connected to four RX antennas, labelled y1, y2, y3 and y4. A transmission channel may be formed between each TX antenna and each RX antenna pair. For example, a signal transmitted from the TX antenna labelled x1 may be received by the RX antenna labelled y2 through channel h21. A signal transmitted through the TX antenna labelled x3 may be received by the RX antenna labelled y1 through channel h13.
[0154] A beam may also be expressed as spatial filter or spatial parameters correspondingly. A beam may be formed by performing amplitude and / or phase weighting on data transmitted or received by at least one antenna port. A beam may be formed by using another method; for example, adjusting a related parameter of an antenna. The beam may include a Tx beam and / or a Rx beam. A beam used to transmit a signal may be referred to as a transmit beam (Tx beam) and can be expressed as spatial domain transmit filter or spatial transmit parameters, correspondingly. The transmit beam indicates distribution of signal strength formed in different directions in space after a signal is transmitted through an antenna. A beam used to receive a signal may be referred to as a receive beam (Rx beam) , and can be expressed as spatial domain receive filter or spatial receive parameters. The receive beam indicates distribution of signal strength that is of a wireless signal received from an antenna and that is in different directions in space. Beam information may include a beam identifier, an antenna port (s) identifier, a channel state information reference signal (CSI-RS) resource identifier, a synchronization signal block (SSB) resource identifier, a sounding reference signal (SRS) resource identifier or other reference signal resource identifier.
[0155] Beamforming technology can be used to form, shape or steer a beam. Beam forming can also be expressed in terms of spatial filtering, directional transmission or directional reception. For example, the beamforming technology may be specifically a digital beamforming technology, an analog beamforming technology, a hybrid digital / analog beamforming technology, or the like. The beamforming may relate to the adjustment of signals communicated via the antenna ports. The adjustments may include amplitude offsets, phase offsets or both of the signals and may be defined by a beamforming weight set.
[0156] A beam alignment mechanism between the transmitting apparatus and the receiving apparatus to ensure communication quality can be called beam management. A beam management mechanism detects and predicts beam failure and mitigates beam failure. Such mechanism should facilitate agile beam recovery and autonomously track, refine and adjust beams. Beam management mainly includes one or more of the following: beam sweeping; beam tracking; beam measurement and reporting; beam prediction; beam switching; beam failure and recovery (BFR) ; and the like.
[0157] For beam sweeping, a base station (e.g., T-TRP 170 and / or NT-TRP 172) may sequentially transmit signals by using beams of different directions and search for an optimal transmit beam aligned with a UE by traversing and sweeping all beams. When performing beam sweeping via beams, the transmitting apparatus sends reference signals via the beams, in a number of different directions, while the receiving apparatus searches for reference signals transmitted by the transmitting apparatus, also in a number of different directions. Examples of a type of reference signal that is transmitted by a transmitting apparatus, may be a channel state information reference signal (CSI-RS) or a positioning reference signal (PRS) . An example of a type of reference signal that may be transmitted by a receiving apparatus may be a sounding reference signal (SRS) . Beam sweeping overhead involves a number of beam pairs (atransmitting apparatus beam and a receiving apparatus beam forming a beam pair) that are searched in order to find one or more beam pairs that have preferred characteristics (e.g., best signal strength) for data communication between the transmitting apparatus and receiving apparatus. Besides the number of beam pairs, the beam sweeping overhead also depends on a duration to perform the measurement (e.g., measurement of the receive signal strength) .
[0158] Beam tracking may be a functionality used by a UE (e.g., ED 110) to make informed decisions about selecting a different beam or beam pair.
[0159] Beam measurements are important for proper data transmission and decoding as well as beam and cell association, as communication parameters may be configured based, at least partly, on the beam measurement values. Conventionally, a UE periodically reports, to an associated base station, such as a base station serving the UE, a base station that may be a potential handover candidate, a base station that may be used as part of beam failure recovery, the beam measurement values, for example the measured beam reference signal received power (RSRP) , signal to noise ratio (SNR) , signal to interference and noise ratio (SINR) , reference signal received quality (RSRQ) , interference power, and / or signal power. Whenever a UE changes its location, speed, or orientation, the beam to be reported to the associated base station may have different RSRP values, because the beam is configured to be transmitted at one or more particular angles or to a specific area. The UE may report, to the base station, measured RSRP values for different types of beams. For example, serving beams, beams that may be used for beam switching, beams that may be used for BFR, and / or beams that may be used for potential handover (HO) .
[0160] Beam prediction may, potentially, reduce the latency for beam switching and, thereby, fluctuations experienced in link quality. Beam prediction may be performed at the base station or at the UE, or both.
[0161] BFR further includes beam failure detection, discovery of new beams and beam recovery procedures.
[0162] A beam pairing relationship may be understood to refer to a pairing relationship between a transmit beam and a receive beam. A beam pairing relationship may also be understood to refer to a pairing relationship between a spatial transmit filter and a spatial receive filter. Transmit and receive beams may be spatially related. For example, parameters for a second beam (e.g., a transmit beam or a receive beam) for a second reference signal can be derived or inferred from information about a first beam (e.g., a Tx beam or an Rx beam) for a first reference signal. A relatively large beamforming gain can be obtained by transmitting a signal between a transmit beam and a receive beam that have a beam pairing relationship.
[0163] An antenna panel may also be called a panel. Each antenna panel may be configured with one or more receive beams and one or more transmit beams. Therefore, the antenna panel can be understood or correspondingly referred to as a unit of an antenna group, a unit of an antenna array or a unit of an antenna sub-array, which can control its Tx or Rx beam independently. A base station, or a UE, may receive a signal by using a receive beam on an antenna panel or may transmit a signal by using a transmit beam on the antenna panel.
[0164] In some implementations, for the UE, antenna panels are distinguished by resources of an uplink reference signal. For example, when the uplink reference signal is a sounding reference signal (SRS) , one antenna panel may correspond to one SRS resource set identifier (ID) . In other words, one SRS resource set ID indicates one antenna panel.
[0165] In some implementations, base stations are distinguished by panel IDs. For example, the panel ID may be carried in a transmission configuration indicator (TCI) .
[0166] An antenna port, which may also be referred to as a port for short, is a transmit antenna identified by a receiving apparatus or a transmit antenna that can be distinguished in a spatial domain. For each virtual antenna, one antenna port may be configured and each virtual antenna may be a weighted combination of multiple physical antennas. Each antenna port may correspond to one reference signal port.
[0167] Two antenna ports are said to be quasi co-located (QCLed) if large-scale properties (or channel features) of the channel over which a symbol on one antenna port is conveyed can be inferred from the channel over which a symbol on the other antenna port is conveyed. The large-scale properties (or channel features) may include one or more of: delay spread; Doppler spread; Doppler shift; average delay; average gain; and spatial RX parameter. The spatial RX parameter may include, for example, angle of arrival (AoA) , average AoA, AoA spread, angle of departure (AoD) , average AoD, AoD spread, RX antenna spatial correlation parameter, TX antenna spatial correlation parameter, transmit beam, receive beam, resource identifier, and the like.
[0168] The angle mentioned above may be a decomposition value of different dimensions or a combination of decomposition values of different dimensions. The two antenna ports mentioned above may be antenna ports with different antenna port numbers and / or antenna ports with a same antenna port number that send or receive information in different time and / or frequency and / or code domain resources and / or antenna ports that have different antenna port numbers to send or receive information in different time and / or frequency and / or code domain resources. The resource identifier may include, for example, a CSI-RS resource identifier, an SRS resource identifier, a synchronization signal / synchronization signal block resource identifier, a demodulation reference signal (DMRS) resource identifier or resource identifier of preamble sequence transmitted on physical random access channel (PRACH) .
[0169] In a MIMO system, to implement functions such as system synchronization, channel information feedback and data transmission, channel estimation may be performed on an UL channel or a DL channel. Channel estimation refers to the process of reconstructing or restoring received signals to compensate for signal distortion caused by channel fading and noise. In channel estimation, a reference signal sent by a transmitting apparatus may be used to track a change in the time domain and / or frequency domain of a channel, so as to reconstruct or restore a received signal. The reference signal may also be referred to as a pilot signal, a reference sequence or the like and may be described as a reference signal in the following for ease of understanding. The reference signal may comprise, for example, a channel state information-reference signal (CSI-RS) , a sounding reference signal (SRS) or a demodulation reference signal (DMRS) .
[0170] The CSI-RS is mainly used for DL channel estimation. For example, a receiving apparatus (e.g., a UE) may perform channel estimation based on a CSI-RS sent by a transmitting apparatus (e.g., a base station) , to feedback channel state information (CSI) based on a channel estimation result. The CSI may include related information such as a channel quality indicator (CQI) , a precoding matrix indicator (PMI) , a layer indicator (LI) , and a rank indicator (RI) . The CSI is used to reconstruct or precode the DL channel.
[0171] Referring to FIG. 12, which illustrates a base station 1202 in communication with a UE 1204, in some implementations, a process in which the base station 1202 obtains CSI may include: sending (step 1210) , by the base station 1202 to the UE 1204, a reference signal; obtaining (step 1212) , by the UE 1204, an estimated CSI value according to the received reference signal; selecting (step 1214) , by the UE 1204, a precoding vector from a codebook according to the estimated CSI value; transmitting, by the UE 1204, feedback including the index of the precoding vector to the base station; and obtaining (step 1216) , by the base station 1202, a CSI reconstruction value with reference to the index of the precoding vector. The CSI reconstruction value can be a CSI closest to the true value of the CSI that can be obtained by the base station.
[0172] A reflective intelligent surface (RIS) may also be known as a large intelligent surface (LIS) , an intelligent reflecting surface (IRS) , a digitally controlled surface (DCS) , intelligent passive mirrors and an artificial radio space. While, in subsequent portions of this disclosure, the acronym “RIS” is used most frequently, it is to be understood then the use of this acronym is for simplicity and is not indented to limit the disclosure.
[0173] A RIS can realize a smart radio environment or “smart radio channel, ” i.e., environment radio propagation properties can be controlled to realize personalized channel for desired communication. The RIS may be established among multiple base stations to produce large scale smart radio channels that serve multiple users. With a controllable environment, RISs may first sense environment information and then feed the environment information back to the system. Accordingly, the system may optimize transmission mode and RIS parameters through smart radio channels, at the transmitting apparatus, channel and receiving apparatus.
[0174] Because of the beamforming gains associated with RISs, exploiting smart radio channels can significantly improve link quality, system performance, cell coverage and cell edge performance in wireless networks. Not all RIS panels use the same structure. Different RIS panels may be designed with various phase adjusting capabilities that range from continuous phase control to discrete control with a handful of levels.
[0175] Another application of RISs is in transmitting apparatuses that directly modulate incident radio wave properties, such as phase, amplitude polarization and / or frequency without the need for active components as in RF chains in traditional MIMO transmitting apparatuses. RIS-based transmitting apparatuses have many merits, such as simple hardware architecture, low hardware complexity, low energy consumption and high spectral efficiency. Therefore, RIS provides a new direction for extremely simple transmitting apparatus design in future radio systems.
[0176] RIS assisted MIMO also may be used to assist fast beamforming with the use of accurate positioning or used to conquer blockage effects through CSI acquisition in mmWave systems. Alternatively, RIS assisted MIMO may be used in non-orthogonal multiple access (NOMA) in order to improve reliability at very low SNR, accommodate more users and enable higher modulation schemes. RIS is also applicable to native physical security transmission, wireless power transfer or simultaneous data and wireless power transfer, and flexible holographic radios.
[0177] The ability to control the environment and network topology through strategic deployment of RISs and other non-terrestrial and controllable nodes is an important paradigm shift in MIMO system.
[0178] Comparing with beamforming at transmit or receiving apparatus sides, spatial beamforming at RIS has more flexibility to realize the beamforming gain as well as to avoid the blockage fading between the transmitting apparatus and receiving apparatus, which is more favorable for high frequency MIMO communication.
[0179] A RIS may include many small reflection elements, often comparable in size with the wavelength (for example, from 1 / 10 of a wavelength to a couple of wavelengths) . Each element may be controlled independently. The control mechanism may be, for example, a bias voltage or a driving current, to change the characteristics of the element. The combination of the control voltages for all elements (and hence the effective response) may be referred to as a RIS pattern. The RIS pattern may control the behavior of the RIS including at least one of the width, shape and direction of a beam, which is referred to as the beam pattern.
[0180] The controlling mechanism of the RIS is often through controlling the phase of a wavefront incident on the surface and reflected by the surface. Other techniques of controlling the RIS include attenuating reflection of the amplitude to reduce the reflected power and “switching off” the surface. Attenuating the power and switching off the surface can be realized by using only a portion of the RIS, or using none of the RIS, for reflection while applying a random pattern to the rest of the panel, or a pattern that reflects the incident wavefront in a direction that is not in a desired direction. Reflecting a signal between two devices, a transmitting apparatus and a receiving apparatus, either of which can be a BS, UE, or relay, may also be considered steering the signal.
[0181] In some portions of this disclosure, RIS may be referred to as a set of configurable elements arranged in a linear array or a planar array. Nevertheless, the analysis and discussions are extendable to other two dimensional or three dimensional arrangements (e.g., a circular array) . A linear array is a vector of N configurable elements and a planar array is a matrix of N×M configurable elements, where M and N are non-zero integers. These configurable elements have the ability to redirect a wave / signal that is incident on the linear or planar array by changing the phase of the wave / signal. The configurable elements are also capable of changing the amplitude, polarization or even the frequency of the wave / signal. In some planar arrays these changes occur as a result of changing bias voltages that control the individual configurable elements of the array via a control circuit connected to the linear or planar array. The control circuit that enables control of the linear or planar array may be connected to a communications network that base stations and UEs communicating with each other are part of. For example, the network that controls the base station may also provide configuration information to the linear or planar array. Control methods other than bias voltage control include, but are not limited to, mechanical deformation and phase change materials.
[0182] Because of their ability to manipulate the incident wave / signal, the low cost of these types of RIS, and because these types of RIS require small bias voltages, RIS have received heightened research interest in the area of wireless communication as a valuable tool for beamforming and / or modulating communication signals.
[0183] A basic example for RIS utilization in beamforming is shown in FIG. 13, wherein each configurable element 4a (unit cell) of a RIS 1304 can change the phase of the incident wave from a source 1302, such that the reflected waves from all of the RIS elements are aligned to the direction of a destination 1306 to increase or maximize its received signal strength (e.g., maximize the signal to noise ratio (SNR) ) . Such a reflection via the RIS 1304 may be referred to as reflect-array beamforming. In some embodiments, the planar array of configurable elements, which may be referred to as RIS panels, can be formed of multiple co-planar RIS sub-panels. In some embodiments, the RIS 1304 can be considered as an extension of base station antennas or a type of distributed antenna. In some embodiments, the RIS 1304 can also be considered as a type of passive relay.
[0184] Effective resource allocation, as depicted in power allocation (PA) and subcarrier-user assignment (SUA) or user pairing (UP) , plays a role in optimizing the performance of NOMA systems. UP involves determining the multiplexed users for each subcarrier. PA involves distributing the overall power budget of the Base Station (BS) across subcarriers and allocating power to users sharing the same subcarrier. Previous research has evaluated and compared different strategies aimed at enhancing spectral efficiency (SE) and promoting fairness among users.
[0185] Recent research has explored methods aimed at mitigating the selection of users with the highest worst channel gain for each subcarrier. One approach involves organizing subcarriers in ascending order, with the user exhibiting the worst channel gain assigned to each subcarrier prior to subcarrier-user assignment (SUA) procedures. Alternatively, these algorithms may focus on maximizing the data rate of each user by prioritizing the maintenance of large channel gains for multiplexed users per subcarrier. In a separate study, a novel power allocation (PA) method is proposed to streamline computation. Furthermore, a genetic algorithm-based PA approach is utilized to optimize the total rate of the NOMA system, employing heuristics to identify suitable solutions. This not only enhances efficiency but also reduces complexity.
[0186] The recent research has highlighted limitations in existing methodologies. For example, while the research demonstrates that NOMA outperforms OMA with respect to spectral efficiency, employing NOMA between two networks that operate on same spectrum will be challenging. When two networks (TN and NTN) use NOMA on the same spectrum, the respective NOMA signals may overlap, thereby causing interference for users of both networks. Also, efficient spectrum utilization requires tight coordination between TN and NTN to avoid overlapping resource allocation for their NOMA transmissions. This can be complex, especially with dynamic traffic patterns. Additionally, NOMA relies on Successive Interference Cancellation (SIC) , in which a strong user decodes and subtracts the signal of a weak user to improve reception quality. When co-channel NOMA interference is present, SIC at the UE becomes more complex due to the additional interference from the other network. Last but not least, effective NOMA coordination might necessitate exchange of information, between TN and NTN, about user locations, channel conditions and NOMA parameters. This exchange of information may require advancements in backhaul communication infrastructure to handle the increased signaling traffic.
[0187] The technical challenges addressed previously primarily revolve around interference mitigation between terrestrial networks (TN) and non-terrestrial networks (NTN) in integrated communication systems.
[0188] These challenges include mitigation of co-channel interference. Mitigating co-channel interference may involve establishing that concurrent operation of terrestrial devices (TN) and non-terrestrial devices (NTN) within the same frequency spectrum will not result in detrimental interference patterns that degrade the performance of both networks.
[0189] The challenges also include employing interference suppression mechanisms within TN and NTN when the two networks are in operation on the same spectrum. Resources can be partially overlapped and / or fully overlapped by the two networks. Interference suppression mechanisms may be employed even if devices have difficulty accessing GNSS, either on a temporary basis or on a permanent basis.
[0190] The challenges further include establishing efficient feedback mechanisms. It may be shown to be challenging to develop streamlined feedback mechanisms that allow UEs to convey interference-related information to network nodes (terrestrial and non-terrestrial devices) in a timely and efficient manner to enable prompt adjustment of transmission parameters.
[0191] The challenges still further include developing a cost-effective model. Improving spectrum sharing can lead to cost savings for both network operators and end-users. By leveraging existing infrastructure and spectrum resources more efficiently, operators can avoid the expenses associated with deploying separate networks or upgrading UE components. The entities that deploy UEs may also benefit from reduced costs, as the entities may find it unnecessary to invest in expensive RF front-end adjustments to access multiple networks.
[0192] The challenges still further include establishing energy-efficient beam management. Known beam-sweeping procedures may be shown to optimize connectivity. However, known beam-sweeping procedures may also be shown to consume considerable energy, due to complexity and duration. Each beam sweep may be shown to involve significant power expenditure, contributing to increased energy consumption and, potentially, contributing to reducing battery life of NTN UEs. Notably, by limiting the number of UE beams during initial access and considering the impact of one network over the other, the complexity and duration of the beam-sweeping procedure may be significantly reduced, which may be shown to lead to improving the energy efficiency of NTN UEs.
[0193] Aspects of the present application relate to interference mitigation in TN-NTN communications. A system model is introduced that assumes a high density of UEs. The system model also considers non-terrestrial devices (satellites) may be equipped with multi-beam antennas that may adjust a beam hopping pattern based on feedback received from UEs or from T-gNBs. Additionally, the system model includes a possibility of multiple terrestrial devices (T-gNBs or aerial gNBs) being under the coverage of the same beam of a given non-terrestrial device.
[0194] The system model further includes an assumption that, in some occasions, the operating frequency of terrestrial and non-terrestrial devices may be the same as the operating frequency of NTN-UEs communicating with satellites while, in other occasions, the operating frequencies may be distinct.
[0195] Moreover, the system model further includes an assumption that terrestrial devices are permitted interact with each other for possible coordination among themselves and an assumption that terrestrial devices are equipped with enough processing power to assist non-terrestrial devices and NTN UEs in reducing the received interference within the networks. Furthermore, the system model further includes an assumption that terrestrial devices are equipped with antennas of higher gain, height and transmit power than the antennas of the UEs and that terrestrial devices are able to directly communicate with non-terrestrial devices.
[0196] The system model may be shown to be applicable over DL and UL and applicable to various approaches to spectrum sharing within TN-NTN networks, including but not limited to normal pairing, where both networks use the same DL and UL spectrum, and reverse pairing, where one network DL spectrum is shared with UL spectrum of the other network and / or vice versa.
[0197] Interference mitigation is already defined for NTN communications. However, a scheme has not yet been proposed that simultaneously minimizes the interference between a TN and a NTN through a NOMA scheme. Aspects of the present application may be shown to reduce complexity at a transmitter and at a receiver at the same time by employing a feedback and / or coordination mechanism between terrestrial and non-terrestrial devices. Indeed, aspects of the present application involve assisting TN with NTN UEs feedback, which, in some conditions, are neither equipped with high processing power nor equipped with access to GNSS for NTN communications. Additionally, aspects of the present application introduce a new signaling mechanism.
[0198] It is known that a non-terrestrial device, in certain scenarios, may transparently facilitate communication between UEs and base stations. That is, the non-terrestrial device neither demodulates nor remodulates the communication. Alternatively, a non-terrestrial device may operate regeneratively. In regenerative operation, a non-terrestrial device utilizes on-board processing capabilities to, for example, demodulate uplink signals and modulate downlink signals between UEs and base stations. Consequently, references herein to functions typically performed by a base station may also, alternatively, be carried out by a UE or another type of network access point (AP) in the wireless terrestrial network.
[0199] Aspects of the present application rely upon an assumption that, in some scenarios, UEs either lack GNSS capability or that GNSS service is unavailable (either temporarily or permanently) for NTN UEs. Aspects of the present application may be shown to be applicable to both transparent payloads and / or regenerative payloads. Additionally, aspects of the present application rely upon an assumption that terrestrial devices possess knowledge of their location.
[0200] In the present application, the term “terrestrial devices” is used to refer to access nodes in 2G, 3G, 4G, 5G or 6G networks. Such access nodes are known to provide connectivity between a UE and a core network. These access nodes are known to include, but not be limited to, gateways.
[0201] Aspects of the present application relate to minimizing received interference by TN UEs and NTN UEs by employing an interference suppression mechanism within the UEs. In scenarios where resources are shared between the two networks, the resources can partially or completely overlap in both the time and frequency domains, leading to potential interference issues. FIG. 14A illustrates a scenario wherein only some of the time slots used by one network coincide with the time slots or frequency bands used by the other network. The term “partially overlapping resources” may be used to describe the scenario illustrated in FIG. 14A. In contrast, FIG. 14B illustrates a scenario wherein the resources are fully synchronized across the time dimension. The term “completely overlapping resources” may be used to describe the scenario illustrated in FIG. 14B.
[0202] From the perspective of UEs in two networks employing overlapping resources, dealing with the partially overlapping resources or completely overlapping resources involves navigating several challenges to maintain reliable communication. When resources overlap, UEs from both networks might transmit or receive on the same frequencies and at the same times, leading to interference that can degrade signal quality and reduce data throughput. For a UE in one network, this means that transmissions could be affected by signals for / from UEs in the other network, causing higher error rates and necessitating retransmissions.
[0203] To manage this, advanced signal processing techniques including, but not limited to, null-steering and beamforming, antenna / RF isolation, transmit signal reconstruction and cancellation, power amplifier noise cancellation, etc. can be utilized at the receiver side to mitigate interference by spatially filtering out unwanted signals. Also, the receiver may include a suitable filter or an equalizer configured for interference cancellation. Additionally, UEs can participate in coordination mechanisms facilitated by the network. This can include dynamic power control, where the UE adjusts its transmission power based on the detected interference levels and the type of resources (shared or dedicated) . By lowering power when high interference is detected, UEs may be shown to reduce the overall interference in the network. Furthermore, UEs may follow enhanced scheduling information from the base station. The enhanced scheduling information may take into account a presence of overlapping resources. The enhanced scheduling information may cause a given UE in one network to adhere to time and frequency assignments that minimize overlap with UEs from the other network, thus reducing contention and interference.
[0204] Aspects of the present application relate to employing, at the receiver side, spatial receivers with multiple antennas to, thereby, exploit spatial diversity to attenuate expected TN or NTN interference. Using spatial receivers, a UE may obtain an estimated Direction of Arrival (DoA) of a desired signal and / or an undesired signal arriving from an interfering signal direction. The UE may then apply a filtering technique, such as null steering, to weaken the undesired signal arriving from the interfering signal direction while minimally affecting the desired signal arriving from a different direction.
[0205] FIG. 15 illustrates, in a flow diagram, example steps in a method representative of aspects of the present application. FIG. 15 illustrates elements of an NTN network and a TN network, including an NTN UE 1502, an other NTN UE 1502-O, a TN UE 1504, a T-gNB 1506 and a NT-gNB 1508.
[0206] The NTN UE 1502 receives (step 1518) a DL signal that has been transmitted (step 1516) by the NT-gNB 1508.
[0207] The NTN UE 1502 also receives (step 1518) an interfering signal that has been transmitted (step 1514) by the T-gNB 1506. It should be clear that the interfering signal is intended to be received (step 1515) by the TN UE 1504 but, due to overlapping resources, is also received (step 1518) by the NTN UE 1502.
[0208] Conveniently, the NTN UE 1502 has received (step 1512) assistance information. The assistance information has been transmitted (step 1510) by the NT-gNB 1508. The assistance information may, for example, include an indication of a location of the T-gNB 1506. The NTN UE 1502 may receive (step 1512) the assistance information over MAC-CE signaling, in an RRC message, in downlink control information (DCI) , etc. and / or in a dedicated signal.
[0209] Upon obtaining (step 1520) an estimate for a DoA of the desired signal, the NTN UE 1502 may transmit (step 1522) , to the other NTN UE 1502-O or a group of NTN UEs (not shown) , the estimate for the DoA of the desired signal.
[0210] In addition to obtaining (step 1520) the estimate for the DoA of the desired signal, the NTN UE 1502 may obtain (step 1524) an estimate for a DoA of the interfering signal. In particular, NTN UE 1502 may use the assistance information received in step 1512 to obtain (step 1524) the estimate for the DoA of the interfering signal. The estimate for the DoA may be obtained (step 1524) , by the NTN UE 1502, in various manners.
[0211] In one manner, the NTN UE 1502 may use assistance information, received in step 1512, regarding the location of the T-gNB 1506 that transmitted (step 1514) the interfering DL signal. The NTN UE 1502 may then obtain (step 1524) the estimate for a DoA based on a combination of the location for the T-gNB 1506 and the location for the NTN UE 1502.
[0212] In another manner, the NTN UE 1502 may obtain an AoA for the interfering DL signal received in step 1518. The NTN UE 1502 may then obtain (step 1524) the estimate for a DoA based on the AoA.
[0213] In another manner, the NTN UE 1502 may obtain a direction of Null forming. The NTN UE 1502 may then obtain (step 1524) the estimate for a DoA based on the direction of Null forming.
[0214] In another manner, the NTN UE 1502 may obtain a null width. The NTN UE 1502 may then obtain (step 1524) the estimate for a DoA based on the null width.
[0215] In another manner, the NTN UE 1502 may obtain a variation over time and direction of the undesired DL signal. The NTN UE 1502 may then obtain (step 1524) the estimate for a DoA based on the variation over time and direction of undesired DL signal.
[0216] In another approach, the NTN UE 1502 may base obtaining (step 1520) the estimate for a DoA on known orbital parameters of non-terrestrial devices. In the context of the desired DL signal received (step 1518) from the NT-gNB 1508, the NTN UE 1502 may obtain (step 1520) the estimate for the DoA for the DL signal received (step 1518) from the NT-gNB 1508 based on known orbital parameters of the NT-gNB 1508. The NTN UE 1502 may consider that “other” signals, defined as signals arriving from directions other than the estimated DoA, are undesired signals.
[0217] In Non-Terrestrial Networks (NTNs) that rely on satellites for communication, ephemeris data may be considered to be key to successful connections. Ephemeris data for each satellite acts as a celestial map that details precise orbital trajectories of each satellite. The ephemeris data for a given satellite comprises specific parameters that define the path of the given satellite around the Earth. These parameters include orbital plane parameters and specific satellite location parameters. The orbital plane parameters include indications of: semi-major axis; eccentricity; inclination; right ascension of the ascending node; and argument of periapsis. The semi-major axis defines an overall size and shape of an elliptical orbit. The eccentricity describes a degree to which the orbit is circular. Notably, the eccentricity of a perfect circle is zero. The inclination is defined as an angle between an orbital plane defined by the path of the satellite and an orbital plane defined by the equator of the Earth. The right ascension of the ascending node represents a point where the satellite crosses the equator moving northward. The argument of periapsis indicates the point in the orbit of the satellite at which the satellite is closer to Earth than at any other point in the same orbit. The specific satellite location parameters include indications of: mean anomaly at a reference time; and epoch. The mean anomaly at a reference time represents an average angular position of the satellite in its orbit at a specific point in time. The epoch represents a reference time for the mean anomaly. With this information, network devices can locate and connect to satellites within the non-terrestrial network. However, traditional approaches are known to use high-precision numbers, leading to bulky data files.
[0218] To address the tendency towards bulky data files, communication between the satellites and network devices may be configured to rely upon efficient signaling techniques, such as: a baseline ephemeris data technique; a signaling specific satellite location technique; a RRC (Radio Resource Control) Signaling technique; and a RRM (Radio Resource Management) Measurement technique.
[0219] According to the baseline ephemeris data technique, network devices are pre-provisioned with a subset of the data, for example, the orbital plane parameters. The subset acts as a starting point, allowing the network devices to identify potential satellite locations within a specific orbital plane. According to the signaling specific satellite location technique, once a potential location has been identified by a network device, the satellite itself transmits additional information during initial contact with the network device. The additional information, including mean anomaly and epoch, may be shown to help the network device to pinpoint the exact position of the satellite within the specific orbital plane. According to the RRC signaling technique, the satellite utilizes RRC signaling to efficiently guide network devices to relevant stored ephemeris data. This signaling leverages indexed and quantized orbital plane information. According to the RRM measurements technique, during an operation involving obtaining RRM measurements, a network device may receive an orbital plane index of a target cell. The orbital plane index may allow the network device to identify a known orbital plane. Using baseline data, the network device may locate the cell within the known orbital plane. By employing these signaling techniques, in combination with ephemeris data, network devices can effectively locate and connect to satellites for successful network access, and smooth communication in NTNs can be achieved.
[0220] In view of estimate obtained (step 1524) for the DoA of the interfering signal, the NTN UE 1502 may apply (step 1526) a filtering technique in a way that nulls undesired signals. The applying (step 1526) of the filtering technique may involve, for example, adjusting a receiving beam. By applying a filtering technique to weaken the DoA of the interfering signal, the NTN UE 1502 may reduce interference with the desired signal arriving from the estimated DoA of the desired signal.
[0221] FIG. 16 illustrates, in a flow diagram, example steps in a method representative of aspects of the present application. FIG. 16 illustrates the elements of the NTN network and the TN network introduced in FIG. 15, including the NTN UE 1502, the TN UE 1504, the other TN UE 1504-O, the T-gNB 1506 and the NT-gNB 1508.
[0222] The TN UE 1504 receives (step 1615) a desired DL signal that has been transmitted (step 1614) by the T-gNB 1506.
[0223] The TN UE 1504 also receives (step 1615) an interfering DL signal that has been transmitted (step 1616) by the NT-gNB 1508. It should be clear that the interfering DL signal is intended to be received (step 1618) by the NTN UE 1502 but, due to overlapping resources, is also received (step 1615) by the TN UE 1504.
[0224] Conveniently, the TN UE 1504 has received (step 1612) assistance information. The assistance information has been has been transmitted (step 1610) by the T-gNB 1506. The assistance information may, for example, include an indication of satellite orbital parameters for the NT-gNB 1508 at the source of the interfering DL signal. The TN UE 1504 may receive (step 1612) the assistance information over MAC-CE signaling, in an RRC message, in downlink control information (DCI) , etc. and / or in a dedicated signal.
[0225] Notably, the transmission (step 1610) of the indication of satellite orbital parameters for the NT-gNB 1508, by the T-gNB 1506, is merely representative of one option for the assistance information. Indeed, more generally, non-terrestrial devices and / or terrestrial devices may transmit assistance information to TN UEs.
[0226] For the desired DL signal received in step 1615, the TN UE 1504 obtains (step 1620) an estimate for a DoA. The estimate for the DoA may be obtained (step 1620) , by the TN UE 1504, in various manners. Upon obtaining (step 1620) the estimate for a DoA, the TN UE 1504 may transmit (step 1622) , to the other TN UE 1504-O or a group of TN UEs (not shown) , the estimate for the DoA.
[0227] In addition to obtaining (step 1620) the estimate for the DoA of the desired signal, the TN UE 1504 may obtain (step 1624) an estimate for a DoA of the interfering DL signal. In particular, TN UE 1504 may use the assistance information received in step 1612 to obtain (step 1624) the estimate for the DoA of the interfering signal.
[0228] The indication of satellite orbital parameters for the NT-gNB 1508, among the assistance information received (step 1612) from the T-gNB 1506, may be shown to allow the TN UE 1504 to obtain (step 1624) the estimate for the DoA for the interfering DL signal that has been transmitted, by the NT-gNB 1508, in step 1614 and received, by the TN UE 1504, in step 1615.
[0229] As alternatives to, or in addition to, the satellite orbital parameters for the NT-gNB 1508, the assistance information received (step 1612) from the T-gNB 1506, may include: an estimate for the AoA, at the TN UE 1504, for the interfering DL signal; a direction of Null forming; a null width; and a variation over time and direction of undesired signals.
[0230] One manner for obtaining (step 1624) the estimate for the DoA for the interfering DL signal may involve the TN UE 1504 using the AoA for the interfering DL signal. In another manner, the TN UE 1504 may obtain (step 1624) the estimate for a DoA for the interfering DL signal based on the direction of Null forming. In another manner, the TN UE 1504 may obtain (step 1624) the estimate for a DoA for the interfering DL signal based on the null width. In another manner, the TN UE 1504 may obtain (step 1624) the estimate for a DoA for the interfering DL signal based on the variation over time and direction of undesired signals.
[0231] In view of the estimate obtained (step 1624) for the DoA for the interfering DL signal, the TN UE 1504 may apply (step 1626) a filtering technique in a way that nulls undesired signals, such as the interfering DL signal. The applying (step 1626) of the filtering technique may involve, for example, adjusting a receiving beam. By applying a filtering technique to weaken the DoA of the interfering signal, the TN UE 1504 may reduce interference with the desired signal arriving from the estimated DoA of the desired signal.
[0232] The preceding may be understood to relate to obtaining (step 1524, step 1624) an estimate for the DoA of an interfering signal for a case wherein the desired signal is a DL signal and the interfering signal is also a DL signal. It should be clear that other aspects of the present application relate to obtaining an estimate for the DoA of an interfering signal for a case wherein the desired signal is a UL signal and the interfering signal is also a UL signal. For these aspects, consider FIG. 17 and FIG. 18.
[0233] As illustrated in FIG. 17, aspects of the present application relate to minimizing interference introduced as the T-gNB 1506 attempts to receive UL signals from the TN UE 1504. The interference may take the form of UL signals transmitted from the NTN UE 1502 towards the NT-gNB 1508.
[0234] FIG. 17 illustrates, in a flow diagram, an attempt to achieve the goal of minimizing interference introduced at the T-gNB 1506. As illustrated in FIG. 17, the T-gNB 1506 may receive (step 1716) a desired UL signal transmitted (step 1714) by the TN UE 1504. However, the T-gNB 1506 may also receive (step 1716) an undesired (interfering) UL signal transmitted (step 1715) by the NTN UE 1502. The UL signal transmitted (step 1715) by the NTN UE 1502 may be meant to be received (step 1718) by the NT-gNB 1508.
[0235] The T-gNB 1506 may obtain (step 1720) an estimate of a DoA of the desired UL signal and / or obtain (step 1724) an estimate of a DoA of an undesired UL signal arriving from an interfering signal direction.
[0236] Assistance information may be signaled (step 1710) , by the NT-gNB 1508, to the T-gNB 1506. The assistance information may include an estimate of the DoA (for the desired signal and / or the undesired signal) . In this case, the obtaining (step 1720, step 1724) the estimate of the DoA may be understood to involve extracting the estimate of the DoA from the assistance information received in step 1712. Indeed, based on knowledge, at the NT-gNB 1508, of the location of the NTN UE 1502 and the T-gNB 1506, the NT-gNB 1508 may be able to estimate the DoA, at the T-gNB 1506, of the interfering UL signal.
[0237] Alternatively, the obtaining (step 1720, step 1724) the estimate of the DoA may be understood to involve the T-gNB 1506 determining the estimate of the DoA for one or both of the desired signal and the undesired signal.
[0238] The assistance information transmitted (step 1710) , by the NT-gNB 1508 may include orbital parameters of the NTN UE 1502. The assistance information may include may include: an estimate for the AoA, at the T-gNB 1506, for the interfering UL signal; a direction of Null forming; a null width; and a variation over time and direction of undesired signals.
[0239] The assistance information may allow the T-gNB 1506 to obtain (step 1724) an estimate for a DoA of the interfering UL signal that may be transmitted (step 1715) by the NTN UE 1502 and received (step 1716) by the T-gNB 1506.
[0240] One manner for obtaining (step 1724) the estimate for the DoA for the interfering UL signal may involve the T-gNB 1506 using the AoA for the interfering DL signal. In another manner, the T-gNB 1506 may obtain (step 1724) the estimate for a DoA for the interfering UL signal based on the direction of Null forming. In another manner, the T-gNB 1506 may obtain (step 1724) the estimate for a DoA for the interfering UL signal based on the null width. In another manner, the T-gNB 1506 may obtain (step 1724) the estimate for a DoA for the interfering UL signal based on the variation over time and direction of undesired signals.
[0241] Responsive to obtaining (step 1724) the estimate for a DoA of the interfering UL signal, the T-gNB 1506 may apply (step 1726) a filtering technique. Applying (step 1726) the filtering technique may involve adjusting a receiving beam in a way that nulls the interfering UL signal. Applying (step 1726) the filtering technique, such as null steering, may be shown to weaken the interfering UL signal arriving from the estimate of the DoA of the interfering UL signal while minimally affecting the estimate of the DoA of the desired UL signal, which is assumed to be distinct from the estimate of the DoA of the interfering UL signal.
[0242] As illustrated in FIG. 18, aspects of the present application relate to minimizing interference introduced as the NT-gNB 1508 attempts to receive UL signals from the NTN UE 1502. The interference may take the form of UL signals transmitted from the TN UE 1504 towards the T-gNB 1506.
[0243] FIG. 18 illustrates, in a flow diagram, an attempt to achieve the goal of minimizing interference introduced at the NT-gNB 1508. As illustrated in FIG. 18, the NT-gNB 1508 may receive (step 1818) a desired UL signal transmitted (step 1816) by the NTN UE 1502. However, the NT-gNB 1508 may also receive (step 1818) an undesired (interfering) UL signal transmitted (step 1814) by the TN UE 1504. The interfering UL signal transmitted (step 1814) by the TN UE 1504 may be meant to be received (step 1815) by the T-gNB 1506.
[0244] The NT-gNB 1508 may obtain (step 1820) an estimate of a DoA of the desired UL signal and / or obtain (step 1824) an estimate of a DoA of the interfering UL signal.
[0245] The T-gNB 1506 may transmit (step 1810) assistance information that is received (step 1812) at the NT-gNB 1508. The assistance information may include the location of the TN UE 1504 from which the NT-gNB 1508 may receive an interfering UL signal. The assistance information may include: an estimate for an AoA, at the NT-gNB 1508, of the interfering UL signal; a direction of Null forming; a null width; and an indication of a variation over time and direction of interfering UL signals.
[0246] Assistance information may be signaled (step 1810) , by the T-gNB 1506, to the NT-gNB 1508. The assistance information may include an estimate of a DoA (for the desired signal and / or the undesired signal) . In this case, the obtaining (step 1820, step 1824) the estimate of the DoA may be understood to involve extracting the estimate of the DoA from the assistance information received in step 1812. Indeed, based on knowledge, at the T-gNB 1506, of the location of the TN UE 1504 and the T-gNB 1506, the T-gNB 1506 may be able to estimate the DoA, at the NT-gNB 1508, of the interfering UL signal.
[0247] Alternatively, the obtaining (step 1820, step 1824) the estimate of the DoA may be understood to involve the NT-gNB 1508 determining the estimate of the DoA for one or both of the desired signal and the undesired signal.
[0248] The assistance information transmitted (step 1810) , by the T-gNB 1506 may include a location for the TN UE 1504. The assistance information may include may include: an estimate for the AoA, at the NT-gNB 1508, for the interfering UL signal; a direction of Null forming; a null width; and a variation over time and direction of undesired signals.
[0249] The assistance information may allow the NT-gNB 1508 to obtain (step 1824) an estimate for a DoA of the interfering UL signal that may be transmitted (step 1814) by the TN UE 1504 and received (step 1818) by the NT-gNB 1508.
[0250] One manner for obtaining (step 1824) the estimate for the DoA for the interfering UL signal may involve the NT-gNB 1508 using the AoA for the interfering UL signal. In another manner, the NT-gNB 1508 may obtain (step 1824) the estimate for a DoA for the interfering UL signal based on the direction of Null forming. In another manner, the NT-gNB 1508 may obtain (step 1824) the estimate for a DoA for the interfering UL signal based on the null width. In another manner, the NT-gNB 1508 may obtain (step 1824) the estimate for a DoA for the interfering UL signal based on the variation over time and direction of undesired signals.
[0251] Responsive to obtaining (step 1824) the estimate for a DoA of the interfering UL signal, the NT-gNB 1508 may apply (step 1826) a filtering technique. Applying (step 1826) the filtering technique may involve adjusting a receiving beam in a way that nulls the interfering UL signal. Applying (step 1826) the filtering technique, such as null steering, may be shown to weaken the interfering UL signal arriving from the estimate of the DoA of the interfering UL signal while minimally affecting the estimate of the DoA of the desired signal, which is assumed to be distinct from the estimate of the DoA of the interfering UL signal.
[0252] Aspects of the present application that are directed to a scenario in which interfering DL signals interfere with reception of desired DL signals have been presented in FIG. 15 and FIG. 16. Aspects of the present application that are directed to a scenario in which interfering UL signals interfere with reception of desired UL signals have been presented in FIG. 17 and FIG. 18.
[0253] Further scenarios may be considered to relate to versions of reverse sharing scenarios, including a scenario wherein TN DL and NTN UL share some resources, as illustrated in FIG. 19. In view of FIG. 19, further aspects of the present application may be understood to relate to obtaining an estimate for the DoA of an interfering signal for a case wherein the desired signal is a DL signal and the interfering signal is a UL signal. In view of FIG. 19, even further aspects of the present application may be understood to relate to obtaining an estimate for the DoA of an interfering signal for a case wherein the desired signal is a UL signal and the interfering signal is a DL signal.
[0254] FIG. 19 illustrates a TN device (a T-gNB) 1906 and an NTN device (an NT-gNB) 1908. The T-gNB 1906 communicates with a TN UE 1904. The NT-gNB 1908 communicates with an NTN UE 1902.
[0255] In FIG. 19, a NTN UE 1902 may be configured to suppress interference from an interfering UL signal, originating at a TN UE 1904 and destined for a T-gNB 1906, to, thereby, enhance reception of a desired DL signal from a NT-gNB 1908 (see, also, FIG. 20) . In some of the aspects, a UE of one network may adjust beams to achieve various benefits. The benefits include minimizing leakage and interference caused by interference signals received from devices in the other network.
[0256] FIG. 20 illustrates, in a flow diagram, an attempt to achieve the goal of minimizing interference introduced at the NTN UE 1902. In FIG. 20, a UL signal transmitted (step 2014) by the TN UE 1904, for receiving (step 2015) by the TN-gNB 1906, may be considered, by the NTN UE 1902, to be an interfering (undesired) signal in the context of a DL signal transmitted (step 2016) by the NT-gNB 1908 for receiving (step 2018) by the NTN UE 1902.
[0257] For the desired DL signal received in step 2018, the NTN UE 1902 may obtain (step 2020) an estimate for a DoA. The estimate for the DoA for the desired DL signal may be obtained (step 2020) , by the NTN UE 1902, in various manners.
[0258] In one manner, the NTN UE 1902 may use assistance information, received in step 2012, regarding the location of the NT-gNB 1908 that has transmitted (step 2016) the DL signal. The NTN UE 1902 may then obtain (step 2020) the estimate for a DoA for the desired DL signal based on a combination of the location for the NT-gNB 1908 and the location for the NTN UE 1902.
[0259] In addition to obtaining (step 2020) the estimate for the DoA of the desired DL signal, the NTN UE 1902 may obtain (step 2024) an estimate for a DoA of the interfering UL signal. In particular, NTN UE 1902 may use the assistance information received in step 2012 to obtain (step 2024) the estimate for the DoA of the interfering UL signal.
[0260] The NTN UE 1902 may base obtaining (step 2024) the estimate for a DoA for the interfering UL signal on the assistance information received in step 2012. In the context for the interfering UL signal received (step 2018) from the TN UE 1904, the NTN UE 1902 may obtain (step 2024) the estimate for the DoA for the interfering UL signal received (step 2018) from the TN UE 1904 based on a location of the TN UE 1904. The location of the TN UE 1904 may be received (step 2012) as part of the assistance information. The NTN UE 1902 may consider that “other” signals, defined as signals arriving from directions other than the estimated DoA, are undesired signals.
[0261] The indication of the location of the TN UE 1904, which location may be received (step 2012) as part of the assistance information, may be shown to allow the NTN UE 1902 to obtain estimates for the DoA for the interfering UL signal that has been transmitted, by the TN UE 1904, in step 2014 and received, by the NTN UE 1902, in step 2018.
[0262] As alternatives to, or in addition to, the location for the TN UE 1904, the assistance information received (step 2012) from the TN UE 1904, may include: an estimate for the AoA, at the NTN UE 1902, for the interfering UL signal; a direction of Null forming; a null width; and a variation over time and direction of undesired signals.
[0263] The NTN UE 1902 may obtain (step 2024) the estimate for a DoA for the interfering UL signal based on the AoA. The NTN UE 1902 may obtain (step 2024) the estimate for a DoA for the interfering UL signal based on the direction of Null forming. The NTN UE 1902 may obtain (step 2024) the estimate for a DoA for the interfering UL signal based on the null width. The NTN UE 1902 may obtain (step 2024) the estimate for a DoA for the interfering UL signal based on the variation over time and direction of undesired signals.
[0264] In view of estimate obtained (step 2024) for the DoA of the interfering UL signal, the NTN UE 1902 may apply (step 2026) a filtering technique in a way that nulls the interfering UL signal. The applying (step 2026) of the filtering technique may involve, for example, adjusting a receiving beam. By applying a filtering technique to weaken the DoA of the interfering UL signal, the NTN UE 1902 may reduce interference with the desired DL signal arriving from the estimated DoA of the desired DL signal.
[0265] An estimated direction of departure (DoD) , from the TN UE 1904, of the interfering UL signal may be obtained at the TN UE 1904. The TN UE 1904 may transmit (step 2010) , in the assistance information, the estimated DoD of the interfering UL signal. The estimated DoD may subsequently be received (step 2012) at the NTN UE 1902.
[0266] In addition to obtaining (step 2020) an estimate of the DoA for the desired DL signal, the NT UE 1902 may employ the estimated DoD of the interfering UL signal, received (step 2012) from the TN UE 1904 as part of the assistance information, to obtain (step 2024) an estimated DoA of the interfering UL signal.
[0267] The NTN UE 1902 may also employ one or more of a variety of algorithms to obtain (step 2024) an estimated DoA of interfering DL signal. For example, it may be expected that signals arriving from different directions will have a specific phase shift between antennas due to the varying path lengths. It follows that the NTN UE 1902 may obtain (step 2024) an estimated DoA of the interfering DL signal by employing an algorithm like Multiple Signal Classification (MUSIC) or Eigenvector Decomposition.
[0268] The NTN UE 1902 may also leverage a spatial correlation between signals received by different antennas, since signals arriving from the same direction may be shown to exhibit a higher correlation when compared to signals arriving from different directions. It follows that, the NTN UE 1902 may determine a spatial correlation matrix and, by analyzing eigenvectors of the spatial correlation matrix, the NTN UE 1902 may obtain (step 2024) an estimate for a DoA of the interfering DL signal.
[0269] The estimated DoD, received (step 2012) from the TN UE 1904, of the interfering UL signal may also be used, by the NT UE 1902, when applying (step 2026) a filtering technique, such as null steering, to weaken the interfering UL signal. The inference may be generated by a main lobe of the interfering UL signal and / or side lobes of the interfering UL signal. In addition to, or instead of, the assistance information transmitted (step 2010) to the NTN UE 1902, the TN UE 1904 may transmit the assistance information to the NT-gNB 1908 or a group of NT-gNBs.
[0270] The assistance information transmitted (step 2010) by the TN UE 1904 may include the location of the TN UE 1904. The assistance information transmitted (step 2010) by the TN UE 1904 may include an estimated AoA of the interfering UL signal at the NTN UE 1902. The information transmitted (step 2010) by the TN UE 1904 may include an estimated DoA of the interfering UL signal at the NTN UE 1902. The assistance information transmitted (step 2010) by the TN UE 1904 may include an estimated direction of Null forming and / or null width and / or their variation over time.
[0271] A scenario similar to the scenario illustrated in FIG. 20 is contemplated with networks reversed and is illustrated in FIG. 21. That is, FIG. 21 illustrates, in a flow diagram, example steps in an attempt to achieve the goal of minimizing interference introduced at the TN UE 1904. In FIG. 21, a UL signal transmitted (step 2116) by the NTN UE 1902, for receiving (step 2118) by the NTN-gNB 1908, may be considered, by the TN UE 1904, to be an interfering (undesired) UL signal in the context of a desired DL signal transmitted (step 2114) by the T-gNB 1906 for receiving (step 2115) by the TN UE 1904.
[0272] An estimated DoD, from the NTN UE 1902, of the interfering UL signal may be obtained at the NTN UE 1902. The NTN UE 1902 may transmit (step 2110) assistance information, which may include the estimated DoD of the interfering UL signal. The assistance information may then be received (step 2112) at the TN UE 1904.
[0273] In addition to obtaining (step 2120) the estimate of the DoA for the desired DL signal, the TN UE 1904 may employ the estimated DoD, extracted from the assistance information received (step 2112) from the NTN UE 1902, of the interfering UL signal when obtaining (step 2124) an estimated DoA of the interfering DL signal.
[0274] The TN UE 1904 may employ one or more of a variety of algorithms to obtain (step 2124) an estimated DoA of the interfering UL signal. For example, it may be expected that signals arriving from different directions will have a specific phase shift between antennas due to the varying path lengths. It follows that the TN UE 1904 may obtain (step 2124) an estimated DoA of the interfering UL signal by employing an algorithm like MUSIC or Eigenvector Decomposition.
[0275] The TN UE 1904 may also leverage a spatial correlation between signals received by different antennas, since signals arriving from the same direction may be shown to exhibit a higher correlation when compared to signals arriving from different directions. It follows that, the TN UE 1904 may determine a spatial correlation matrix and, by analyzing eigenvectors of the spatial correlation matrix, the TN UE 1904 may obtain (step 2124) an estimate for a DoA of the interfering UL signal.
[0276] The estimated DoD of the interfering DL signal, extracted from the assistance information received (step 2112) from the NTN UE 1902, may also be used when applying (step 2126) a filtering technique, such as null steering, to weaken the interfering UL signal. The inference may be generated by a main lobe of the interfering signal and / or side lobes of the interfering signal.
[0277] The assistance information transmitted (step 2110) by the NTN UE 1902 may include orbital parameters for the NTN UE 1902. The assistance information transmitted (step 2110) by the NTN UE 1902 may include an estimated AoA of the interfering UL signal at the TN UE 1904. The information transmitted by the NTN UE 1902 may include an estimated DoA of the interfering signal at the TN UE 1904. The information transmitted by the NTN UE 1902 may include an estimated direction of Null forming and / or null width and / or their variation over time.
[0278] In addition to transmitting the assistance information to the TN UE 1904, the NTN UE 1902 may transmit (not shown) the assistance information to the T-gNB 1906 or a group of T-gNBs.
[0279] As illustrated in FIG. 22, aspects of the present application relate to minimizing interference introduced as the T-gNB 1906 attempts to receive UL signals from the TN UE 1904. The interference may take the form of DL signals transmitted from the NT-gNB 1908 towards the NTN UE 1902. That is, FIG. 22 illustrates, in a flow diagram, example steps in an attempt to achieve the goal of minimizing interference introduced at the T-gNB 1906.
[0280] FIG. 22 illustrates, in a flow diagram, an attempt to achieve the goal of minimizing interference introduced at the T-gNB 1906. As illustrated in FIG. 22, the T-gNB 1906 may receive (step 2216) a desired UL signal transmitted (step 2214) by the TN UE 1904. However, the T-gNB 1906 may also receive (step 2216) an undesired (interfering) DL signal transmitted (step 2219) by the NT-gNB 1908. The DL signal transmitted (step 2215) by the NT-gNB 1908 may be meant to be received (step 2218) by the NTN UE 1902.
[0281] The T-gNB 1906 may obtain (step 2220) an estimate of a DoA of the desired UL signal and / or obtain (step 2224) an estimate of a DoA of the interfering DL signal arriving from an interfering signal direction.
[0282] Assistance information may be signaled (step 2210) , by the NT-gNB 1908, to the T-gNB 1906. The assistance information may include an estimate of the DoD for the interfering DL signal. The obtaining (step 2224) the estimate of the DoA for the interfering DL signal may be understood to involve the T-gNB 1906 extracting the estimate of the DoD from the assistance information received in step 2212.
[0283] Alternatively, the obtaining (step 2220, step 2224) the estimate of the DoA may be understood to involve the T-gNB 1906 determining the estimate of the DoA for one or both of the desired signal and the undesired signal.
[0284] The NT-gNB 1908 may transmit (step 2210) assistance information to the T-gNB 1906. The assistance information may include orbital parameters of the NTN UE 1902. The assistance information may include an AoA. The assistance information may include a direction of Null forming. The assistance information may include a null width. The assistance information may include an indication of a variation over time and direction of undesired signals.
[0285] The assistance information may allow the T-gNB 1906 to obtain (step 2224) an estimate for a DoA of the interfering DL signal that may be transmitted (step 2215) by the NT-gNB 1908 and received (step 2216) by the T-gNB 1906. Responsive to obtaining (step 2224) the estimate for a DoA of the interfering DL signal, the T-gNB 1906 may apply (step 2226) a filtering technique. Applying (step 2226) the filtering technique may involve adjusting a receiving beam in a way that nulls the interfering DL signal. Applying (step 2226) the filtering technique, such as null steering, may be shown to weaken the interfering DL signal arriving from the estimate of the DoA of the interfering DL signal while minimally affecting the estimate of the DoA of the desired UL signal, which is assumed to be distinct from the estimate of the DoA of the interfering DL signal.
[0286] The T-gNB 1906 may employ one or more of a variety of algorithms to obtain (step 2224) an estimated DoA of interfering DL signal. For example, it may be expected that signals arriving from different directions will have a specific phase shift between antennas due to the varying path lengths. It follows that the T-gNB 1906 may obtain (step 2224) an estimated DoA of the interfering DL signal by employing an algorithm like MUSIC or Eigenvector Decomposition.
[0287] The T-gNB 1906 may also leverage a spatial correlation between signals received by different antennas, since signals arriving from the same direction may be shown to exhibit a higher correlation when compared to signals arriving from different directions. It follows that, the T-gNB 1906 may determine a spatial correlation matrix and, by analyzing eigenvectors of the spatial correlation matrix, the T-gNB 1906 may obtain (step 2224) an estimate for a DoA of the interfering DL signal.
[0288] FIG. 23 illustrates, in a flow diagram, an attempt to achieve the goal of minimizing interference introduced at the NT-gNB 1908. The T-gNB 1906 may transmit (step 2310) assistance information that is received (step 2312) at the NT-gNB 1908. The assistance information may include the location of the T-gNB 1906 from which the NT-gNB 1908 may receive an interfering DL signal. The assistance information may include an estimate for an AoA, at the NT-gNB 1908, of an interfering DL signal. The assistance information may include a direction of Null forming. The assistance information may include a null width. The assistance information may include an indication of a variation over time and direction of an interfering UL signal.
[0289] As illustrated in FIG. 23, the NT-gNB 1908 may receive (step 2318) a desired UL signal transmitted (step 2316) by the NTN UE 1902. However, the NT-gNB 1908 may also receive (step 2318) an undesired (interfering) DL signal transmitted (step 2314) by the T-gNB 1906. The interfering DL signal transmitted (step 2314) by the T-gNB 1906 may be meant to be received (step 2315) by the TN UE 1904.
[0290] The NT-gNB 1908 may obtain (step 2320) an estimate of a DoA of the desired UL signal and / or obtain (step 2324) an estimate of a DoA of the interfering DL signal.
[0291] Assistance information may be signaled (step 2310) , by the T-gNB 1906, to the NT-gNB 1908. The assistance information may include an estimate of a DoD for the interfering DL signal. In this case, the obtaining (step 2324) the estimate of the DoA may be understood to involve extracting the estimate of the DoD from the assistance information received in step 2312.
[0292] Alternatively, the obtaining (step 2320, step 2324) the estimate of the DoA may be understood to involve the NT-gNB 1908 determining the estimate of the DoA for one or both of the desired signal and the undesired signal.
[0293] The T-gNB 1906 may transmit (step 2310) assistance information to the NT-gNB 1908. The assistance information may allow the NT-gNB 1908 to obtain (step 2324) an estimate for a DoA of the interfering DL signal that may be transmitted (step 2314) by the T-gNB 1906 and received (step 2318) by the NT-gNB 1908. Responsive to obtaining (step 2324) the estimate for a DoA of the interfering DL signal, the NT-gNB 1908 may apply (step 2326) a filtering technique. Applying (step 2326) the filtering technique may involve adjusting a receiving beam in a way that nulls the interfering DL signal. Applying (step 2326) the filtering technique, such as null steering, may be shown to weaken the interfering DL signal arriving from the estimate of the DoA of the interfering DL signal while minimally affecting the estimate of the DoA of the desired UL signal, which is assumed to be distinct from the estimate of the DoA of the interfering DL signal.
[0294] The NT-gNB 1908 may employ one or more of a variety of algorithms to obtain (step 2324) an estimated DoA of interfering UL signal. For example, it may be expected that signals arriving from different directions will have a specific phase shift between antennas due to the varying path lengths. It follows that the NT-gNB 1908 may obtain (step 2324) an estimated DoA of the interfering UL signal by employing an algorithm like MUSIC or Eigenvector Decomposition.
[0295] The NT-gNB 1908 may also leverage a spatial correlation between signals received by different antennas, since signals arriving from the same direction may be shown to exhibit a higher correlation when compared to signals arriving from different directions. It follows that, the NT-gNB 1908 may determine a spatial correlation matrix and, by analyzing eigenvectors of the spatial correlation matrix, the NT-gNB 1908 may obtain (step 2324) an estimate for a DoA of the interfering UL signal.
[0296] In another scenario presented in FIG. 24, an apparatus, such as the NTN UE 1502, may be configured with an awareness of a location for at least one gNB in a terrestrial network (e.g., the T-gNB 1506) . The configuration may occur by way of receiving (step 2412) assistance information. The assistance information may, for example, be transmitted (step 2410) by the NT-gNB 1508.
[0297] The NTN UE 1502 may able to determine that a UL signal transmitted (step 1715) in the context of the non-terrestrial network may be a source of interference in the context of the terrestrial network. That is, the NTN UE 1502 may determine (not shown) that future transmitting (step 1715) of the UL signal towards the NT-gNB 1508 may act as interference in the context of the UL signal transmitted (step 1714) by the TN UE 1504 for receiving (step 1716) by the T-gNB 1506. A reduction to this type of interference has been discussed, in view of FIG. 17, as being carried out at the T-gNB 1506. Aspects of the present application relate to efforts to reduce this type of interference that are carried out at the NTN UE 1502. In such aspects, the NTN UE 1502 may obtain (step 2424) a direction of departure (DoD) of the UL signal to be transmitted by itself in step 1715. Based on a known location for the T-gNB 1506 (received in step 2412) and the DoD of the UL signal, the NTN UE 1502 may expect the UL signal to be transmitted in step 1715 to cause interference based on being in line with the location of the T-gNB 1506. In such a case, the NTN UE 1502 may apply a filtering technique, such as null steering, to weaken the interference expected to be caused by a main lobe and / or one or more side lobes of the UL signal transmitted in step 1715.
[0298] In a further scenario presented in FIG. 25, an apparatus, such as the TN UE 1504, may be configured with ephemeris data for at least one gNB in a non-terrestrial network (e.g., the NT-gNB 1508) . The configuration may occur by way of receiving (step 2512) assistance information. The assistance information may, for example, be transmitted (step 2510) by the T-gNB 1506.
[0299] The TN UE 1504 may able to determine that a UL signal transmitted (step 1814) in the context of the terrestrial network may be a source of interference in the context of the non-terrestrial network. That is, the TN UE 1504 may determine (not shown) that a future transmitting (step 1814) of the UL signal towards the T-gNB 1506 may act as interference in the context of the UL signal transmitted (step 1816) by the NTN UE 1502 for receiving (step 1818) by the NT-gNB 1508. A reduction to this type of interference has been discussed, in view of FIG. 18, as being carried out at the NT-gNB 1508. Aspects of the present application relate to efforts to reduce this type of interference that are carried out at the TN UE 1504. In such aspects, the TN UE 1504 may obtain (step 2524) a direction of departure (DoD) of the UL signal to be transmitted by itself in step 1814. Based on known ephemeris data for the NT-gNB 1508 (received in step 2512) and the DoD of the UL signal, the TN UE 1504 may expect the UL signal to be transmitted in step 1814 to cause interference based on being in line with the momentary location of the NT-gNB 1508. In such a case, the TN UE 1504 may apply a filtering technique, such as null steering, to weaken the interference expected to be caused by a main lobe and / or one or more side lobes of the UL signal transmitted in step 1814.
[0300] Some aspects of the obtaining (step 1524, step 1624, step 1724, step 1824, step 2024, step 2124, step 2224, step 2324) an estimate for the DoA of an interfering signal, as discussed hereinbefore, rely upon the receiver being equipped with access to a GNSS. It follows that some adaptations of the methods represented in the flow diagrams of FIG. 15, FIG. 16, FIG. 17, FIG. 18, FIG. 20, FIG. 21, FIG. 22 and FIG. 23 may be implemented for situations wherein a given receiver is not equipped with equipment for accessing a GNSS. Such adaptations may also be implemented for occasions wherein one or more errors occur in GNSS calculation at the given receiver. Such adaptations may further be implemented for occasions wherein a GNSS is unavailable, either temporarily or permanently.
[0301] The adaptations may involve obtaining, at a receiver using spatial receivers, an estimated DoA of incoming signals, including both desired signals and interfering signals. The obtaining may be based on the features of signals received by multiple antennas at the receiver. The receiver may then, as discussed hereinbefore, apply a filtering technique, such as null steering, to weaken an interfering signal direction while minimally affecting a desired signal arriving from a desired signal direction that is distinct from the interfering signal direction.
[0302] FIG. 26A illustrates an NTN device (an NT-gNB) 2608 and a T-gNB 2606. The NT-gNB 2608 communicates with an NTN UE 2602. Interference signals may arrive at the NTN UE 2602 from the T-gNB 2606.
[0303] The NTN UE 2602 may employ one or more of a variety of algorithms to estimate a DoA of the interfering signal. For example, it may be expected that signals arriving from different directions will have a specific phase shift between antennas due to the varying path lengths. It follows that the NTN UE 2602 may estimate a DoA of the interfering signal by employing an algorithm like MUSIC or Eigenvector Decomposition.
[0304] The NTN UE 2602 may also leverage a spatial correlation between signals received by different antennas, since signals arriving from the same direction may be shown to exhibit a higher correlation when compared to signals arriving from different directions. It follows that, the NTN UE 2602 may determine a spatial correlation matrix and, by analyzing eigenvectors of the spatial correlation matrix, the NTN UE 2602 may obtain an estimate for a DoA of the interfering signal.
[0305] Upon obtaining the estimate for the DoA of the interfering signal, the NTN UE 2602 may adjust a receiving beam in a way that nulls undesired signals, as illustrated in FIG. 26B.
[0306] Some aspects of the obtaining an estimate for the DoA of an interfering UL signal, as discussed hereinbefore in the context of FIG. 17, FIG. 18, FIG. 20 and FIG. 21 rely upon the receiver being equipped with access to a GNSS. It follows that some adaptations may be implemented for situations wherein a given receiver is not equipped with equipment for accessing a GNSS. Such adaptations may also be implemented for occasions wherein an error occurs in GNSS calculation at the given receiver. Such adaptations may further be implemented for occasions wherein a GNSS is unavailable, either temporarily or permanently.
[0307] The adaptations may involve deploying a coordination mechanism between TN and NTN. Indeed, gNBs may assist UEs to identify undesired signals with relatively greater ease and with relatively greater accuracy.
[0308] The adaptations may involve a given NTN UE deactivating one beam at a time and asking one or more T-gNBs to transmit within a particular time interval. This enables the given NTN UE to identify a DoA and characteristics of undesired interference signals during the particular time interval. By analyzing the received signals, the given NTN UE may determine an angle of arrival and other properties of undesired interference signals.
[0309] Similarly, in a subsequent time interval, the given NTN UE may activate a beam and transmit on the activated beam while T-gNBs cease transmission on the activated beam within the subsequent time interval. This allows TN UEs to identify a DoA and characteristics of undesired interference signals using the same principle.
[0310] By comparing the information gathered from both time intervals, the UEs can refine their understanding of the interference, aiding in interference suppression and enhancing the precoding process at the receiver. Ultimately, the coordinated effort between NTN and TN, along with the iterative DoA calculation and characterization of undesired signals, facilitates better interference suppression techniques. This not only enhances the overall performance of the network but also improves the efficiency of precoding at the receiver, leading to a more robust and reliable communication system for all users involved.
[0311] In an effort to facilitate decoding at UEs and to minimize possible leakage between terrestrial networks and terrestrial networks, devices within the respective networks may, according to aspects of the present application, strategically adjust transmission power levels for signals destined for their respective UEs.
[0312] To suppress received interference within two networks, both networks may allow their UEs to measure interfering signals. The measurements are expected to allow the UEs to identify characteristics and directions of the interfering signals. To allow for the measuring of interfering signals, the gNBs of both networks may signal indications of specific muted periods. During the muted periods, the respective UEs may perform measurements without interference from their own network.
[0313] FIG. 27 illustrates an NT-gNB 2708 in communication with an NTN UE 2702. The NT-gNB 2708 transmits (step 2710) , to the NTN UE 2702, an indication of muted periods. The NTN UE 2702 receives (step 2712) the indication. During one or more of the indicated muted periods, the NTN UE 2702 may measure (step 2714) received signals. Given that the measuring (step 2714) is timed to occur during a non-terrestrial network muted period, it is understood that the signals received during the measuring (step 2714) are likely to be from the terrestrial network. That is, the signals received during the measuring (step 2714) are likely to be undesired (interfering) signals. The measuring (step 2714) may be understood to involve obtaining measurements of received would-be interfering signals. The measurements may include a received signal strength indicator (RSSI) and a Signal-to-Interference-plus-Noise Ratio (SINR) of the received would-be interfering signals. The NTN UE 2702 may process (step 2716) the measurements of the would-be interfering signals to identify characteristics of the would-be interfering signals. The characteristics may include a modulation and coding scheme, beamforming and spatial characteristics, and signal patterns. The NTN UE 2702 may also process (step 2716) the measurements, in combination with advanced antenna techniques, to identify a direction of arrival (DoA) for the would-be interfering signals.
[0314] The NTN UE 2702 may use the characteristics and the DoA of the would-be interfering signals (identified in step 2716) to, at some later point in time, distinguish actual interfering terrestrial network signals and suppress reception of the actual interfering terrestrial network signals.
[0315] FIG. 27 also illustrates a T-gNB 2706 in communication with a TN UE 2704. The T-gNB 2706 transmits (step 2720) , to the TN UE 2704, an indication of muted periods. The TN UE 2704 receives (step 2722) the indication. During one or more of the indicated muted periods, the TN UE 2704 may measure (step 2724) received signals. Given that the measuring (step 2724) is timed to occur during a terrestrial network muted period, it is understood that the signals received during the measuring (step 2724) are likely to be from the non-terrestrial network. That is, the signals received during the measuring (step 2724) are likely to be undesired (interfering) signals. The measuring (step 2724) may be understood to involve obtaining measurements of the received would-be interfering signals. The measurements may include a received signal strength indicator (RSSI) and a Signal-to-Interference-plus-Noise Ratio (SINR) of the would-be interfering signals. The TN UE 2704 may process (step 2726) the measurements of the would-be interfering signals to identify characteristics of the would-be interfering signals. The TN UE 2704 may also process (step 2726) the measurements, in combination with advanced antenna techniques, to identify a direction of arrival for the would-be interfering signals.
[0316] The TN UE 2704 may use the characteristics and the DoA of the would-be interfering signals (identified in step 2726) to, at some later point in time, distinguish actual interfering non-terrestrial network signals and suppress reception of the actual interfering non-terrestrial network signals.
[0317] FIG. 28 illustrates a T-gNB 2806 in bidirectional communication with an NT-gNB 2808. Devices within the respective networks may, periodically, exchange information about characteristics of their transmissions. That is, the NT-gNB 2808 may transmit (step 2820) NTN transmission characteristics. The NTN transmission characteristics may be received (step 2822) by the T-gNB 2806. The T-gNB 2806 may transmit (step 2824) TN transmission characteristics. The TN transmission characteristics may be received (step 2816) by the NT-gNB 2808.
[0318] The transmission characteristics may include, but not be limited to: T-gNB location; satellite orbital parameters; typical power levels used for NOMA signals; and an indication of a TN deployment scenario. The indication of the TN deployment scenario may, for example, indicate an urban deployment scenario, a rural deployment scenario, etc. The indication of the TN deployment scenario may, for other examples, indicate information regarding the characteristics of deployment such as, but not limited to, one or more of inter-site-distance, gNB height, number of antennas and beam width.
[0319] Based on the exchanged information, each network can develop power control strategies with power levels that have been optimized for its own NOMA users. Indeed, the T-gNB 2806 may optimize (step 2828) power levels for the TN NOMA users and the NT-gNB 2808 may optimize (step 2830) power levels for the NTN NOMA users. The T-gNB 2806 may then commence transmitting (step 2832) , to the TN NOMA users, based upon the TN optimized power levels. The NT-gNB 2808 may commence transmitting (step 2834) , to the NTN NOMA users, based upon the NTN optimized power levels.
[0320] The strategies may aim to maintain a target average power level for their UEs. The strategies may involve pre-configuring a leakage factor based on the specific NOMA scheme they are using. The specific NOMA scheme may be shown to define various factors. One example factor is a power allocation ratio between strong users and weak users. The strategies may aim to avoid exceeding a maximum power limit to, thereby, minimize interference leakage and abide by limits of maximum power spectral density. The strategies may be shown to help those users that are partially or fully overlapped on some resources. The strategies may be shown to minimize the received interference within two networks.
[0321] Up to this point, interference suppression has been discussed in the context of inter-network interference. It should be clear that aspects of the present application may be implemented in the context of intra-network interference. That is, it is contemplated that there may be scenarios in which a UE may receive a desired signal and an interfering signal from the same type of network (TN or NTN) . One version of such a scenario may be referred to as a case of inter-beam interference. It should be clear that aspects of the present application will allow the UE to receive assistance information and, based on the assistance information related to a second network, apply a filtering technique to weaken an estimated direction of the interfering signal relative to an estimated direction of the desired signal.
[0322] In review, there are aspects of the present application that involve information being shared with a TN UE. Non-terrestrial devices and / or terrestrial devices may transmit, to the TN UE, orbital parameters for a non-terrestrial device. The orbital parameters allow the TN UE to obtain a direction for undesired signals, specifically for the case wherein the undesired signals have been transmitted by the non-terrestrial device that corresponds to the received orbital parameters. Upon obtaining the direction, the TN UE may adjust a receiving beam in a manner that nulls the direction of the undesired signals. In aspects of the present application, a terrestrial device may calculate and / or obtain assistance information for undesired signals. The assistance information may include AoA / direction of Null forming / null width and / or their variation over time. The terrestrial device may then transmit, directly to a corresponding TN UE or group of TN UEs, the assistance information.
[0323] It is notable that a TN UE may obtain a DoD for a desired signal. The desired signal for the TN UE may, at the same time, represent an undesired signals from the perspective of an NTN UE. It follows that, the TN UE, by sharing the DoD of the desired signal with another network, may be considered to being providing assistance information for use by UEs in the other network, with the assistance information relating to undesired signal directions.
[0324] It should be appreciated that one or more steps of the embodiment methods provided herein may be performed by corresponding units or modules. For example, data may be transmitted by a transmitting unit or a transmitting module. Data may be received by a receiving unit or a receiving module. Data may be processed by a processing unit or a processing module. The respective units / modules may be hardware, software, or a combination thereof. For instance, one or more of the units / modules may be an integrated circuit, such as field programmable gate arrays (FPGAs) or application-specific integrated circuits (ASICs) . It will be appreciated that where the modules are software, they may be retrieved by a processor, in whole or part as needed, individually or together for processing, in single or multiple instances as required, and that the modules themselves may include instructions for further deployment and instantiation.
[0325] Although a combination of features is shown in the illustrated embodiments, not all of them need to be combined to realize the benefits of various embodiments of this disclosure. In other words, a system or method designed according to an embodiment of this disclosure will not necessarily include all of the features shown in any one of the figures or all of the portions schematically shown in the figures. Moreover, selected features of one example embodiment may be combined with selected features of other example embodiments.
[0326] Although this disclosure has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments, as well as other embodiments of the disclosure, will be apparent to persons skilled in the art upon reference to the description. It is therefore intended that the appended claims encompass any such modifications or embodiments.
[0327] In the present disclosure, the terms “a, ” “an” and “one” are defined to mean “at least one. ” That is, these terms do not exclude a plural number of items, unless stated otherwise.
[0328] In the present disclosure, terms such as “substantially, ” “generally” and “about, ” which modify a value, condition or characteristic of a feature of an example embodiment, should be understood to mean that the value, condition or characteristic is defined within tolerances that are acceptable for the proper operation of this example embodiment for its intended application.
[0329] In the present disclosure, unless stated otherwise, the terms “connected” and “coupled, ” and derivatives and variants thereof, refer herein to any structural or functional connection or coupling, either direct or indirect, between two or more elements. For example, the connection or coupling between the elements can be acoustical, mechanical, optical, electrical, thermal, logical or any combinations thereof.
[0330] In the present disclosure, expressions such as “match, ” “matching” and “matched, ” including variants and derivatives thereof, are intended to refer herein to a condition in which two or more elements are either the same or within some predetermined tolerance of each other. That is, these terms are meant to encompass not only “exactly” or “identically” matching the two elements but also “substantially, ” “approximately” or “subjectively” matching the two or more elements, as well as providing a higher or best match among a plurality of matching possibilities.
[0331] In the present disclosure, the expression “based on” is intended to mean “based at least partly on. ” That is, this expression can mean “based solely on” or “based partially on” and, so, should not be interpreted in a limited manner. More particularly, the expression “based on” could also be understood as meaning “depending on, ” “representative of, ” “indicative of, ” “associated with” or similar expressions.
[0332] In the present disclosure, the terms “system” and “network” may be used interchangeably in embodiments of this application. “At least one” means one or more and “a plurality of” means two or more. The term “and / or” describes an association relationship of associated objects and indicates that three relationships may exist. For example, A and / or B may indicate the following three cases: only A exists; both A and B exist; and only B exists; where A and B may be singular or plural. The character “ / ”usually indicates an “or” relationship between associated objects. “At least one of the following items (pieces) ” or a similar expression thereof indicates any combination of these items, including a single item (piece) or any combination of a plurality of items (pieces) . For example, “at least one of A, B, or C” includes: only A; only B; only C; A and B; A and C; B and C; or A, B, and C. “at least one of A, B, and C” may also be understood as including: only A; only B; only C; A and B; A and C; B and C; or A, B, and C. In addition, unless otherwise specified, ordinal numbers such as “first” and “second” in embodiments of this application are used to distinguish between a plurality of objects and are not used to limit a sequence, a time sequence, priorities, or importance of the plurality of objects.
[0333] The terms “receive, ” “detect” and “decode” as used herein can have several different meanings depending on the context in which these terms are used. For example, without special note, the term “receive” may indicate that information (e.g., DCI, or MAC-CE, RRC signaling or TB) is received successfully by the receiving node, which means the receiving side correctly detects and decodes it. In this scenario, “receive” may cover “detect” and “decode” or may indicate the same thing, e.g., “receive paging” means decoding paging correctly and obtaining the paging successfully. Accordingly, “the receiving side does not receive paging” means the receiving side does not detect and / or decoding the paging. The phrase “paging is not received” means the receiving side tries to detect and / or decoding the paging, but does not obtain the paging successfully. The term “receive” may sometimes indicate that a signal arrives at the receiving side, but does not mean the information in the signal is detected and decoded correctly, and then the receiving side performs detecting and decoding on the signal to obtain the information carried in the signal. In this scenario, “receive, ” “detect” and “decode” may indicate different procedures at the receiving side to obtain the information.
[0334] A person skilled in the art should understand that embodiments of this application may be provided as a method, an apparatus (or system) , computer-readable storage medium, or a computer program product. Therefore, this application may use a form of a hardware-only embodiment, a software-only embodiment, or an embodiment with a combination of software and hardware. Moreover, this application may use a form of a computer program product that is implemented on one or more computer-usable storage media (including but not limited to a disk memory, an optical memory, and the like) that include computer-usable program code.
[0335] This application is described with reference to the flowcharts and / or block diagrams of the method, the device (system) , and the computer program product according to this application. It should be understood that computer program instructions may be used to implement each process and / or each block in the flowcharts and / or the block diagrams and a combination of a process and / or a block in the flowcharts and / or the block diagrams. The computer program instructions may be provided for a general-purpose computer, a dedicated computer, an embedded processor, or a processor of another programmable data processing device to generate a machine, so that the instructions executed by the computer or the processor of the another programmable data processing device generate an apparatus for implementing a specific function in one or more procedures in the flowcharts and / or in one or more blocks in the block diagrams.
[0336] The computer program instructions may alternatively be stored in a computer-readable memory that can indicate a computer or another programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate an artifact that includes an instruction apparatus. The instruction apparatus implements a specific function in one or more procedures in the flowcharts and / or in one or more blocks in the block diagrams.
[0337] The computer program instructions may alternatively be loaded onto a computer or another programmable data processing device, so that a series of operations and steps are performed on the computer or the another programmable device, so that computer-implemented processing is generated. Therefore, the instructions executed on the computer or the another programmable device provide steps for implementing a specific function in one or more procedures in the flowcharts and / or in one or more blocks in the block diagrams.
[0338] It is clear that a person skilled in the art can make various modifications and variations to this application without departing from the scope of this application. This application is intended to cover these modifications and variations of this application provided that they fall within the scope of protection defined by the following claims and their equivalent technologies.
Claims
1.A communication method for spectrum sharing between a first network and a second network, the method comprising:receiving, at an apparatus of the first network, assistance information related to the second network;obtaining, at the apparatus based, at least in part, on the assistance information, an estimated direction of an interfering signal originating from the second network; andapplying a spatial domain filtering technique to weaken the estimated direction of the interfering signal.2.The method of claim 1, further comprising obtaining, at the apparatus, an estimated direction of a desired signal so that the applying the filtering technique may be carried out relative to the estimated direction of the desired signal.3.The method of claim 2, wherein the first network is a terrestrial network (TN) and the second network is a non-terrestrial network (NTN) .4.The method of claim 3, wherein the apparatus comprises a TN user equipment and wherein the assistance information pertains to a device of the NTN.5.The method of claim 4, wherein the assistance information comprises orbital parameters for the device.6.The method of claim 4, wherein the assistance information comprises an estimated Direction of Departure (DoD) of the interfering signal.7.The method of claim 6, wherein the obtaining the estimated direction of the interfering signal comprises processing the DoD of the interfering signal from the device.8.The method of any one of claims 3 to 7, wherein the obtaining the estimated direction of the interfering signal comprises employing an algorithm based on signals arriving from different directions having a specific phase shift between antennas.9.The method of claim 8, wherein the algorithm comprises Multiple Signal Classification (MUSIC) .10.The method of claim 8, wherein the algorithm comprises Eigenvector Decomposition.11.The method of any one of claims 3 to 8, wherein the apparatus comprises a terrestrial network device and wherein the assistance information pertains to a device of the NTN.12.The method of claim 11, wherein the assistance information comprises orbital parameters for the device.13.The method of claim 11, wherein the assistance information comprises an estimate for a direction of arrival, at the terrestrial network device, for the interfering signal.14.The method of any one of claims 2 to 13, wherein the first network is a non-terrestrial network (NTN) and the second network is a terrestrial network (TN) .15.The method of claim 14, wherein the apparatus comprises an NTN user equipment and wherein the assistance information pertains to a device of the TN.16.The method of claim 15, wherein the assistance information comprises a location for the device.17.The method of claim 15, wherein the assistance information comprises an estimated direction of Departure (DoD) of the interfering signal.18.The method of claim 17, wherein the obtaining the estimated direction of the interfering signal comprises processing the DoD of the interfering signal from the device.19.The method of any one of claims 14 to 18, wherein the apparatus comprises a non-terrestrial network device and wherein the assistance information pertains to a device of the TN.20.The method of claim 19, wherein the assistance information comprises to a location for the device.21.The method of claim 19, wherein the assistance information further comprises an estimate for an Angle of Arrival (AoA) for the interfering signal.22.The method of any one of claims 1 to 21, wherein the first network is a terrestrial network (TN) and the second network is a TN.23.The method of any one of claims 1 to 21, wherein the first network is a non-terrestrial network (NTN) and the second network is a distinct NTN.24.A communication method for spectrum sharing between a first network and a second network, the method comprising:receiving, at an apparatus of the first network, signals from the second network;processing, at the apparatus based on received assistance information, the signals received from the second network to, thereby, obtain an estimated direction of an interfering signal from the second network; andapplying a spatial domain filtering technique to weaken the estimated direction of the interfering signal.25.The method of claim 24, wherein the processing comprises employing an algorithm based on the signals from the second network arriving from different directions having a specific phase shift between antennas.26.The method of claim 25, wherein the algorithm comprises Multiple Signal Classification (MUSIC) .27.The method of claim 25, wherein the algorithm comprises Eigenvector Decomposition.28.The method of any one of claims 24 to 27, wherein the processing comprises:determining, for signals arriving from different directions, a spatial correlation matrix; andanalyzing eigenvectors of the spatial correlation matrix.29.A communication method for spectrum sharing between a first network and a second network, the method comprising:receiving, at a user equipment of the first network and from an apparatus of the first network, an indication of a first-network muted time interval;measuring, at the user equipment of the first network, would-be interfering signals during the first-network muted time interval and obtaining measurements of the would-be interfering signals received during the first-network muted time interval; andprocessing, at the user equipment of the first network, the measurements of the would-be interfering signals to, thereby, identify characteristics of the interfering signal.30.The method of claim 29, further comprising combining antenna techniques with the processing to, thereby, determine a direction of arrival for the would-be interfering signal.31.The method of claim 30, further comprising using the characteristics and the direction of arrival of the would-be interfering signals to suppress reception of actual interfering signals.32.A communication method for spectrum sharing between a first network and a second network, the method comprising:transmitting, from an apparatus of the first network and to an apparatus of the second network, an indication of first network transmission characteristics;receiving, at the apparatus of the first network and from the apparatus of the second network, an indication of second network transmission characteristics;optimizing, at the apparatus of the first network, first network power levels for first network users; andtransmitting, at the apparatus of the first network, signals to the first network users, based upon the first network power levels.33.The method of claim 32, wherein the characteristics comprise one or more of: a location for the apparatus of the first network; typical power levels used for signals; and an indication of a first network deployment scenario.34.The method of claim 33, wherein the indication of the first network deployment scenario comprises an indication of one or more of: inter-site-distance; a height for the apparatus of the first network; a number of antennas at the apparatus of the first network; and beam width.35.A communication apparatus, configured to perform the method according to any one of claims 1 to 34.36.The communication apparatus of claim 35, comprising:a receiving unit configured to receive assistance information related to the second network; anda processing unit configured to:obtain, based, at least in part, on the assistance information, an estimated direction of an interfering signal originating from the second network; andapply a spatial domain filtering technique to weaken the estimated direction of the interfering signal.37.The communication apparatus of claim 35, comprising:a receiving unit configured to receive signals from the second network; anda processing unit configured to:process based on received assistance information, the signals received from the second network to, thereby, obtain an estimated direction of an interfering signal from the second network; andapply a spatial domain filtering technique to weaken the estimated direction of the interfering signal.38.The communication apparatus of claim 35, comprising:a receiving unit configured to receive an indication of a first-network muted time interval; anda processing unit configured to:measure would-be interfering signals during the first-network muted time interval and obtaining measurements of the would-be interfering signals received during the first-network muted time interval; andprocess the measurements of the would-be interfering signals to, thereby, identify characteristics of the interfering signal.39.The communication apparatus of claim 35, comprising:a transmitting unit configured to transmit to an apparatus of the second network, an indication of first network transmission characteristics;a receiving unit configured to receive from the apparatus of the second network, an indication of second network transmission characteristics;a processing unit configured to optimize first network power levels for first network users; andthe transmitting unit further configured to transmit signals to the first network users, based upon the first network power levels.40.The communication apparatus of claim 35, comprising:an interface unit configured to receive assistance information related to the second network; anda processing unit configured to:obtain, based, at least in part, on the assistance information, an estimated direction of an interfering signal originating from the second network; andapply a spatial domain filtering technique to weaken the estimated direction of the interfering signal.41.The communication apparatus of claim 35, comprising:an interface configured to receive signals from the second network; anda processing unit configured to:process based on received assistance information, the signals received from the second network to, thereby, obtain an estimated direction of an interfering signal from the second network; andapply a spatial domain filtering technique to weaken the estimated direction of the interfering signal.42.The communication apparatus of claim 35, comprising:an interface unit configured to receive an indication of a first-network muted time interval; anda processing unit configured to:measure would-be interfering signals during the first-network muted time interval and obtaining measurements of the would-be interfering signals received during the first-network muted time interval; andprocess the measurements of the would-be interfering signals to, thereby, identify characteristics of the interfering signal.43.The communication apparatus of claim 35, comprising:an interface unit configured to:transmit to an apparatus of the second network, an indication of first network transmission characteristics; andreceive from the apparatus of the second network, an indication of second network transmission characteristics; anda processing unit configured to optimize first network power levels for first network users; andan interface unit further configured to transmit signals to the first network users, based upon the first network power levels.44.A communication system, wherein the communication system comprises at least two of a first communication apparatus configured to perform the method of any one of claims 1 to 23, a second communication apparatus configured to perform the method of any one of claims 24 to 28, a third communication apparatus configured to perform the method of any one of claims 29 to 31, and a fourth communication apparatus configured to perform the method of any one of claims 32 to 34.45.An apparatus in a first network, the apparatus comprising:one or more processors; anda memory storing instructions which, when executed by the one or more processors, cause the apparatus to:receive assistance information related to a second network;obtain, based, at least in part, on the assistance information, an estimated direction of an interfering signal from the second network; andapply a spatial domain filtering technique to weaken the estimated direction of the interfering signal.46.A computer-readable storage medium having instructions stored thereon which, when executed by one or more processors cause the one or more processors to perform the method of any one of claims 1 to 34.47.A computer program product storing instructions which, when executed, cause an apparatus to perform the method of any one of claims 1 to 34.
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