Superimposed orthogonal frequency division multiplexing waveforms for low-power signals

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting higher data transmission rates. A method and apparatus for superimposed orthogonal frequency division multiplexing (OFDM) waveforms for low-power signals. A method of a user terminal (UE) in a wireless communication system comprises the steps of identifying a set of OFDM symbols for a low-power signal and determining an on-off-key (OOK) waveform for a low-power signal. Each OFDM symbol comprises one or more segments. Each segment corresponds to an ON waveform or an OFF waveform. The method further comprises the steps of determining a set of superimposed OFDM waveforms and receiving a low-power signal based on the OOK waveform and the set of superimposed OFDM waveforms. Each superimposed OFDM waveform is applied to a segment when the segment corresponds to an ON waveform.

Description

Technology Field

[0001] The present disclosure generally relates to wireless communication systems, and more specifically, the present disclosure relates to a method and apparatus for overlaid orthogonal frequency-division multiplexing (OFDM) waveforms for low-power signals. Background Technology

[0002] Wireless communication has been one of the most successful innovations in modern history. Recently, the number of wireless communication service subscribers has surpassed 5 billion and is growing rapidly. The demand for wireless data traffic is increasing rapidly due to the growing consumption of mobile data devices such as smartphones, tablets, "notepad" computers, netbooks, eBook readers, and machine-type devices, as well as their rising popularity among enterprises. To meet this high growth in mobile data traffic and support new applications and deployments, improvements in wireless interface efficiency and coverage are of paramount importance.

[0003] 5G mobile communication technology defines a wide frequency band to enable fast transmission speeds and new services, and can be implemented not only in frequency bands below 6 GHz ('Sub 6 GHz'), such as 3.5 gigahertz (3.5 GHz), but also in ultra-high frequency bands called millimeter waves (mmWave), such as 28 GHz and 39 GHz ('Above 6 GHz'). In addition, for 6G mobile communication technology, which is referred to as a system beyond 5G, implementation in the terahertz band (e.g., the 3 terahertz (3 THz) band at 95 GHz) is being considered to achieve transmission speeds 50 times faster and ultra-low latency reduced to one-tenth compared to 5G mobile communication technology.

[0004] In the early stages of 5G mobile communication technology, aiming to satisfy service support and performance requirements for enhanced Mobile BroadBand (eMBB), Ultra-Reliable Low-Latency Communications (URLLC), and massive Machine-Type Communications (mMTC), technologies such as beamforming and Massive MIMO to mitigate path loss and increase transmission distance in ultra-high frequency bands, support for various numerologies (such as the operation of multiple subcarrier spacings) and dynamic operation of slot formats for the efficient utilization of ultra-high frequency resources, initial access techniques to support multi-beam transmission and broadband, definition and operation of Band-Width Parts (BWP), Low Density Parity Check (LDPC) codes for high-volume data transmission, new channel coding methods such as Polar Codes for the reliable transmission of control information, and L2 pre-processing (L2 Standardization has been carried out for pre-processing, network slicing which provides a dedicated network specialized for specific services, and other methods.

[0005] Currently, discussions are underway to improve and enhance the performance of the initial 5G mobile communication technology, taking into account the services that the 5G mobile communication technology was intended to support. Additionally, standardization of the physical layer is in progress for technologies such as V2X (Vehicle-to-Everything), which helps autonomous vehicles make driving decisions and enhance user convenience based on their own location and status information transmitted by the vehicle; NR-U (New Radio Unlicensed), which aims for system operation in unlicensed bands to comply with various regulatory requirements; NR terminal low power consumption technology (UE Power Saving); Non-Terrestrial Network (NTN), which is direct terminal-satellite communication for securing coverage in areas where communication with the terrestrial network is impossible; and positioning.

[0006] In addition, standardization is underway in the field of wireless interface architecture / protocols for technologies such as the Industrial Internet of Things (IIoT) for supporting new services through linkage and convergence with other industries, Integrated Access and Backhaul (IAB) which provides nodes for expanding network service areas by integrating wireless backhaul links and access links, Mobility Enhancement including Conditional Handover and Dual Active Protocol Stack (DAPS) Handover, and 2-step Random Access (2-step RACH for NR) which simplifies random access procedures. Standardization is also underway in the field of system architecture / services for 5G baseline architectures (e.g., Service based Architecture, Service based Interface) for incorporating Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies, and Mobile Edge Computing (MEC), which provides services based on the location of the terminal.

[0007] When such 5G mobile communication systems are commercialized, connected devices, which are increasing explosively, will be connected to communication networks. Accordingly, it is expected that there will be a need to enhance the functionality and performance of 5G mobile communication systems and to integrate the operation of connected devices. To this end, new research is planned to be conducted on 5G performance improvement and complexity reduction, support for AI services, support for metaverse services, and drone communication using eXtended Reality (XR), Artificial Intelligence (AI), and Machine Learning (ML) to efficiently support Augmented Reality (AR), Virtual Reality (VR), and Mixed Reality (MR).

[0008] Furthermore, the advancement of these 5G mobile communication systems encompasses multi-antenna transmission technologies such as new waveforms to guarantee coverage in the terahertz band of 6G mobile communication technology, Full Dimensional MIMO (FD-MIMO), array antennas, and large-scale antennas; metamaterial-based lenses and antennas to improve terahertz band signal coverage; high-dimensional spatial multiplexing technology using OAM (Orbital Angular Momentum); and Reconfigurable Intelligent Surface (RIS) technology; as well as Full Duplex technology for enhancing frequency efficiency and system networks in 6G mobile communication technology; AI-based communication technologies that realize system optimization by utilizing satellites and AI from the design stage and internalizing end-to-end AI support functions; and the realization of services of complexity exceeding the limits of terminal computing capabilities by utilizing ultra-high-performance communication and computing resources. It could serve as a foundation for the development of next-generation distributed computing technologies.

[0009] The information above is provided for background purposes only to aid in understanding the content of this disclosure. No determination has been made and no claim has been made as to whether any of the foregoing may be applied as prior art in relation to the present invention. The problem to be solved

[0010] The present disclosure relates to a method and apparatus for superimposed OFDM waveforms for low-power signals.

[0011] The technical objectives achieved by the various embodiments of the present disclosure are not limited to those mentioned above, and other technical objectives not mentioned above may be considered by those skilled in the art from the various embodiments of the present disclosure described below. means of solving the problem

[0012] In one embodiment, a user terminal (UE) is provided. The UE includes a user terminal (UE) in a wireless communication system. The UE includes a processor configured to identify a set of OFDM symbols for a low-power signal, determine an on-off-key (OOK) waveform for a low-power signal, and determine a set of superimposed OFDM waveforms. Each OFDM symbol includes one or more segments. Each segment corresponds to an ON waveform or an OFF waveform. Each superimposed OFDM waveform is applied to the segment when the segment corresponds to an ON waveform. The UE further includes a transceiver operably coupled to the processor. The transceiver is configured to receive a low-power signal based on the OOK waveform and the set of superimposed OFDM waveforms.

[0013] In another embodiment, a base station (BS) in a wireless communication system is provided. The BS includes a processor configured to identify a set of OFDM symbols for a low-power signal, determine an OOK waveform for a low-power signal, and determine a set of superimposed OFDM waveforms. Each OFDM symbol includes one or more segments. Each segment corresponds to an ON waveform or an OFF waveform. Each superimposed OFDM waveform is applied to the segment when the segment corresponds to an ON waveform. The BS further includes a transceiver operably coupled to the processor. The transceiver is configured to transmit a low-power signal based on the OOK waveform and the set of superimposed OFDM waveforms.

[0014] In another embodiment, a method performed by a user terminal is provided. The method includes the steps of identifying a set of OFDM symbols for a low-power signal and determining an OOK waveform for the low-power signal. Each OFDM symbol includes one or more segments. Each segment corresponds to an ON waveform or an OFF waveform. The method further includes the steps of determining a set of superimposed OFDM waveforms and receiving a low-power signal based on the OOK waveform and the set of superimposed OFDM waveforms. Each superimposed OFDM waveform is applied to a segment when the segment corresponds to an ON waveform.

[0015] Other technical features may be readily apparent to those skilled in the art from the following drawings, descriptions, and claims. Effects of the invention

[0016] The present disclosure may provide a method and apparatus for superimposed OFDM waveforms for low-power signals.

[0017] The effects that can be achieved through this disclosure are not limited to those mentioned in the various embodiments, and other unmentioned effects will be clearly understood by those skilled in the art from the description below.

[0018] Before proceeding to the detailed description below, it may be helpful to provide definitions of specific words and phrases used throughout this patent specification. The term "couple" and its derivatives denote direct or indirect communication between two or more elements, regardless of whether the elements are in physical contact with each other. The terms "transmit," "receive," and "communicate," and their derivatives, include both direct and indirect communication. The terms "include," "comprise," and their derivatives mean inclusion rather than limitation. The term "or" is a general term meaning "and / or." The phrase "associated with" and its derivatives mean include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, have a relationship to or with, etc. The term "controller" means any device, system, or part thereof that controls at least one operation. Such a controller may be implemented in hardware or as a combination of hardware and software and / or firmware.Functions associated with a specific controller may be processed locally or remotely, centrally, or distributed. The phrase "at least one," when used with a list of items, means that one or more different combinations of the listed items may be used. For example, "at least one of A, B, and C" includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A, B, and C.

[0019] Additionally, the various functions described below may be implemented or supported by one or more computer programs, each of which is formed of computer-readable program code and implemented on a computer-readable medium. The terms “application” and “program” refer to one or more computer programs, software components, instruction sets, procedures, functions, objects, classes, instances, related data, or parts thereof configured for implementation in suitable computer-readable program code. The phrase “computer-readable program code” includes types of computer code including source code, object code, and executable code. The phrase “computer-readable medium” includes any type of medium accessible by a computer, such as ROM (read-only memory), RAM (random access memory), hard disk drives, compact discs (CDs), digital video discs (DVDs), or any other type of memory. “Non-transient” computer-readable media exclude communication links that transmit wired, wireless, optical, transient electrical, or other signals. Non-transient computer-readable media include media in which data is permanently stored and media in which data is stored and later overwritten, such as rewritable optical discs or erasable memory devices.

[0020] Definitions for other specific words and phrases are provided throughout this patent specification. Those skilled in the art should understand that, in many cases, if not most, these definitions may apply not only to conventional usage but also to future uses of such defined words and phrases. Brief explanation of the drawing

[0021] For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken together with the accompanying drawings, in which similar reference numerals indicate similar parts. FIG. 1 illustrates an exemplary wireless network according to embodiments of the present disclosure. FIG. 2 illustrates an exemplary gNodeB (gNB) according to an embodiment of the present disclosure. FIG. 3 illustrates an exemplary UE according to embodiments of the present disclosure. FIG. 4a illustrates an example of a wireless transmission path according to embodiments of the present disclosure. FIG. 4b illustrates an example of a wireless receiving path according to embodiments of the present disclosure. FIG. 5 illustrates an OFDM-based waveform superimposed on an OOK-based waveform according to embodiments of the present disclosure. FIG. 6 illustrates an OFDM-based waveform superimposed on an OOK-based waveform according to embodiments of the present disclosure. FIG. 7 illustrates an OFDM-based waveform superimposed on an OOK-based waveform according to embodiments of the present disclosure. FIG. 8 illustrates an exemplary method performed by a UE in a wireless communication system according to embodiments of the present disclosure. FIG. 9 illustrates another exemplary method performed by a UE in a wireless communication system according to embodiments of the present disclosure. Specific details for implementing the invention

[0022] FIGS. 1 through 9 described below, and various non-limiting embodiments used to illustrate the principles of the present disclosure in this patent specification, are for illustrative purposes only and should not be interpreted in any way as limiting the scope of the present disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any appropriately configured system or device.

[0023] To meet the demand for increasing wireless data traffic since the establishment of 4G communication systems and to enable various vertical applications, 5G / NR communication systems have been developed and are currently being deployed. 5G / NR communication systems are implemented in higher frequency bands (e.g., 28 GHz or 60 GHz bands) to achieve higher data rates, or in lower frequency bands such as 6 GHz to enable more robust coverage and mobility support. To reduce radio wave propagation loss and increase transmission distance, beamforming, MIMO (Massive Multiple-Input Multiple-Output), FD-MIMO (Full-dimensional MIMO), array antennas, analog beamforming, and massive antenna technologies are being discussed in 5G / NR communication systems.

[0024] In addition, in 5G / NR communication systems, development for improving system networks is underway based on advanced small cells, cloud radio access network (RAN), ultra-dense network, D2D (Device-to-Device) communication, wireless backhaul, mobile network, cooperative communication, CoMP (Coordinated Multi-Point), receiver interference cancellation, etc.

[0025] Discussion regarding 5G systems and associated frequency bands is for reference only, as specific embodiments of the present disclosure may be implemented in 5G systems. However, the present disclosure is not limited to 5G systems or associated frequency bands, and embodiments of the present disclosure may be utilized in relation to any frequency band. For example, aspects of the present disclosure may be applied to deployments of 5G communication systems, 6G, or even later releases capable of using the terahertz (THz) band.

[0026] The following documents and standard descriptions, namely, [REF1] 3GPP TS 38.211 v17.1.0, “NR; Physical channels and modulation;” [REF2] 3GPP TS 38.212 v17.1.0, “NR; Multiplexing and channel coding;” [REF3] 3GPP TS 38.213 v17.1.0, “NR; Physical layer procedures for control;” [REF4] 3GPP TS 38.214 v17.1.0, “NR; Physical layer procedures for data;” [REF5] 3GPP TS 38.331 v17.1.0, “NR; Radio Resource Control (RRC) protocol specification.” are incorporated herein by reference as the full text is provided herein.

[0027] FIGS. 1 through 3 below describe various embodiments implemented in wireless communication systems and also using orthogonal frequency division multiplexing (OFDM) or orthogonal frequency division multiple access (OFDMA) communication technologies. The descriptions in FIGS. 1 through 3 do not imply physical or structural limitations on the manner in which different embodiments may be implemented. Different embodiments of the present disclosure may be implemented in any suitably configured communication system.

[0028] FIG. 1 illustrates an exemplary wireless network (100) according to embodiments of the present disclosure. The embodiment of the wireless network (100) illustrated in FIG. 1 is for illustrative purposes only. Other embodiments of the wireless network (100) may be used without departing from the scope of the present disclosure.

[0029] As illustrated in FIG. 1, the wireless network (100) includes a gNB (101) (e.g., a base station, BS), a gNB (102), and a gNB (103). The gNB (101) communicates with the gNB (102) and the gNB (103). Additionally, the gNB (101) also communicates with at least one network (130), e.g., the Internet, a private IP (Internet Protocol) network, or another data network.

[0030] The gNB (102) provides wireless broadband access to the network (130) to a first plurality of user terminals (UEs) located within the coverage area (120) of the gNB (102). The first plurality of UEs include a UE (111) that may be located in a small or medium-sized business; a UE (112) that may be located in a large business; a UE (113) that may be a Wi-Fi hotspot; a UE (114) that may be located in a first residential area; a UE (115) that may be located in a second residential area; and a UE (116) that may be a mobile device such as a mobile phone, a wireless laptop, a wireless PDA, etc. The gNB (103) provides wireless broadband access to the network (130) to a second plurality of UEs located within the coverage area (125) of the gNB (103). The second plurality of UEs include a UE (115) and a UE (116). In some embodiments, one or more of the gNBs (101-103) can communicate with each other and with UEs (111-116) using 5G / NR, LTE (long term evolution), LTE-A (long term evolution-advanced), WiMAX, WiFi, or other wireless communication technologies.

[0031] Depending on the network type, the terms “base station” or “BS” may refer to a component (or set of components) configured to provide wireless access to a network, for example, a transmitting point (TP), a transmitting-receiving point (TRP), an enhanced base station (eNodeB or gNB), a 5G / NR base station (gNB), a macrocell, a femtocell, a WiFi access point (AP), or other wirelessly enabled device. A base station may provide wireless access according to one or more wireless communication protocols, such as 5G / NR 3GPP NR, LTE (long term evolution), LTE-A (LTE-advanced), HSPA (high speed packet access), Wi-Fi 802.11a / b / g / n / ac, etc. For convenience, the terms “BS” and “TRP” are used interchangeably in this patent specification to refer to network infrastructure that provides wireless access to a remote terminal. Additionally, depending on the network type, the terms "user terminal" or "UE" may refer to any component such as "mobile station," "subscriber station," "remote terminal," "wireless terminal," "receiving point," or "user device." For convenience, the terms "user terminal" and "UE" are used in this patent specification to refer to remote wireless equipment wirelessly accessing the BS, whether the UE is a mobile device (e.g., a mobile phone or a smartphone) or a fixed device generally considered (e.g., a desktop computer or a vending machine).

[0032] The dashed lines show the approximate ranges of the coverage areas (120 and 125), which are depicted as nearly circular for illustrative and explanatory purposes only. It should be clearly understood that the coverage areas associated with the gNBs, e.g., coverage areas (120 and 125), may have different forms, including irregular shapes, depending on the configuration of the gNBs and changes in the wireless environment related to natural and artificial obstacles.

[0033] As described in more detail below, one or more of the UEs (111-116) include circuitry, programming, or a combination thereof for identifying superimposed OFDM waveforms for low-power signals. In certain embodiments, one or more of the gNBs (101-103) include circuitry, programming, or a combination thereof for enabling superimposed OFDM waveforms for low-power signals.

[0034] Although FIG. 1 illustrates an example of a wireless network, various modifications may be made to FIG. 1. For example, the wireless network (100) may include any number of gNBs and any number of UEs in any suitable arrangement. Additionally, a gNB (101) may communicate directly with any number of UEs to provide these UEs with wireless broadband access to the network (130). Similarly, each gNB (102-103) may communicate directly with the network (130) to provide UEs with direct wireless broadband access to the network (130). Additionally, the gNBs (101, 102, and / or 103) may provide access to other or additional external networks, such as external telephone networks or other types of data networks.

[0035] FIG. 2 illustrates an exemplary gNB (102) according to embodiments of the present disclosure. The embodiment of the gNB (102) shown in FIG. 2 is for illustrative purposes only, and the gNBs (101 and 103) of FIG. 1 may have the same or similar configurations. However, gNBs are made up of various configurations, and FIG. 2 does not limit the scope of the present disclosure to any specific implementation of the gNB.

[0036] As shown in FIG. 2, the gNB (102) includes multiple antennas (205a-205n), multiple transceivers (210a-210n), a controller / processor (225), a memory (230), and a backhaul or network interface (235).

[0037] Transceivers (210a to 210n) receive incoming RF (radio frequency) signals, such as signals transmitted by UEs within the network (100), from antennas (205a to 205n). Transceivers (210a to 210n) down-convert the incoming RF signals to generate IF or baseband signals. The IF or baseband signals are processed by the receive (RX) processing circuit of the transceivers (210a to 210n) and / or the controller / processor (225), which generates processed baseband signals by filtering, decoding, and / or digitizing the baseband or IF signals. The controller / processor (225) may further process the baseband signals.

[0038] The transmit (TX) processing circuit of the transceivers (210a-210n) and / or the controller / processor (225) receives analog or digital data (e.g., voice data, web data, email, or interactive video game data) from the controller / processor (225). The TX processing circuit encodes, multiplexes, and / or digitizes the outgoing baseband data to generate processed baseband or IF signals. The transceivers (210a-210n) upconvert the baseband or IF signals into RF signals transmitted through the antennas (205a-205n).

[0039] The controller / processor (225) may include one or more processors or other processing units that control the overall operation of the gNB (102). For example, the controller / processor (225) may control the reception of UL (uplink) channel signals and the transmission of DL (downlink) channel signals by the transceivers (210a-210n) according to well-known principles. The controller / processor (225) may also support additional functions, such as more advanced wireless communication functions. For example, the controller / processor (225) may support beamforming or directional routing operations in which outward signals from multiple antennas (205a-205n) are processed differently to effectively steer them in a desired direction. As another example, the controller / processor (225) may support methods for enabling superimposed OFDM waveforms for low-power signals. Any of the various other functions can be supported in the gNB (102) by the controller / processor (225).

[0040] The controller / processor (225) can also execute programs and other processes residing in memory (230), such as processes for enabling superimposed OFDM waveforms for low-power signals. The controller / processor (225) can move data into or out of memory (230) according to the requirements of the execution process.

[0041] Additionally, the controller / processor (225) is coupled to a backhaul or network interface (235). The backhaul or network interface (235) enables the gNB (102) to communicate with other devices or systems through a backhaul connection or through a network. The interface (235) may support communications through any suitable wired or wireless connection(s). For example, if the gNB (102) is implemented as part of a cellular communication system (e.g., supporting 5G / NR, LTE, or LTE-A), the interface (235) may enable the gNB (102) to communicate with other gNBs through a wired or wireless backhaul connection. If the gNB (102) is implemented as an access point, the interface (235) enables the gNB (102) to transmit to a larger network (e.g., the Internet) through a wired or wireless local area network or through a wired or wireless connection. The interface (235) includes any suitable structure that supports wired or wireless connections, for example, communications via Ethernet or transceivers.

[0042] The memory (230) is coupled to the controller / processor (225). Part of the memory (230) may include RAM, and another part of the memory (230) may include flash memory or other ROM.

[0043] Although FIG. 2 illustrates an example of gNB (102), various modifications may be made to FIG. 2. For example, gNB (102) may include any number of each component shown in FIG. 2. Additionally, the various components of FIG. 2 may be combined, further subdivided, or omitted, and additional components may be added as needed.

[0044] FIG. 3 illustrates an exemplary UE (116) according to embodiments of the present disclosure. The embodiment of the UE (116) illustrated in FIG. 3 is for illustrative purposes only, and the UEs (111 to 115) of FIG. 1 may have the same or similar configurations. However, UEs are made up of various configurations, and FIG. 3 does not limit the scope of the present disclosure to any specific implementation of the UE.

[0045] As illustrated in FIG. 3, the UE (116) includes antenna(s) (305), transceiver(s) (310), and microphone (320). Additionally, the UE (116) includes a speaker (330), a processor (340), an input / output (I / O) interface (IF) (345), an input device (350), a display (355), and memory (360). The memory (360) includes an operating system (OS) (361) and one or more applications (362).

[0046] Transceiver(s) (310) receive an inward RF signal transmitted by a gNB of a wireless network (100) from an antenna (305). Transceiver(s) (310) downconvert the inward RF signal to generate an intermediate frequency (IF) or baseband signal. The IF or baseband signal is processed by an RX processing circuit of the transceiver(s) (310) and / or processor (340) to generate a processed baseband signal by filtering, decoding, and / or digitizing the baseband or IF signal. The RX processing circuit transmits the processed baseband signal to a speaker (330) (e.g., for voice data) or is processed by the processor (340) (e.g., for web browsing data).

[0047] The TX processing circuit of the transceiver(s) (310) and / or processor (340) receives analog or digital voice data from the microphone (320) or other outward baseband data (e.g., web data, email, or interactive video game data) from the processor (340). The TX processing circuit encodes, multiplexes, and / or digitizes the outward baseband data to generate a processed baseband or IF signal. The transceiver(s) (310) upconverts the baseband or IF signal into an RF signal transmitted through the antenna(s) (305).

[0048] The processor (340) may include one or more processors or other processing devices and may control the overall operation of the UE (116) by executing an OS (361) stored in memory (360). For example, the processor (340) may control the reception of DL channel signals and the transmission of UL channel signals by the transceiver(s) (310) according to well-known principles. In some embodiments, the processor (340) includes at least one microprocessor or microcontroller.

[0049] The processor (340) may also execute other processes and programs residing in memory (360). For example, the processor (340) may execute processes for identifying overlapping OFDM waveforms for low-power signals as described in the embodiments of the present disclosure. The processor (340) may move data into or out of memory (360) as required by the execution process. In some embodiments, the processor (340) is configured to execute applications (362) based on the OS (361) or based on signals received from gNBs or an operator. Additionally, the processor (340) is coupled to an I / O interface (345) that provides the UE (116) with the ability to connect to other devices, such as laptop computers and portable computers. The I / O interface (345) is a communication path between these peripherals and the processor (340).

[0050] The processor (340) is also coupled to an input device (350) and a display (355), for example, including a touchscreen, a keypad, etc. An operator of the UE (116) can input data into the UE (116) using the input device (350). The display (355) may be, for example, a liquid crystal display, a light-emitting diode display, or other display capable of rendering text and / or at least limited graphics from websites.

[0051] The memory (360) is coupled to the processor (340). Part of the memory (360) may include random access memory (RAM), and another part of the memory (360) may include flash memory or other read-only memory (ROM).

[0052] Although FIG. 3 illustrates an example of a UE (116), various modifications may be made to FIG. 3. For example, the various components of FIG. 3 may be combined, further subdivided, or omitted, and additional components may be added as needed. As one specific example, the processor (340) may be divided into multiple processors, for example, one or more central processing units (CPUs) and one or more graphics processing units (GPUs). In another example, the transceiver(s) (310) may include any number of transceivers and signal processing chains and may be connected to any number of antennas. Also, although FIG. 3 illustrates a UE (116) configured as a mobile phone or smartphone, UEs may be configured to operate as other types of mobile or stationary devices.

[0053] FIGS. 4a and FIGS. 4b illustrate examples of wireless transmission and reception paths (400 and 450), respectively, according to embodiments of the present disclosure. For example, the transmission path (400) may be described as being implemented in a gNB (e.g., gNB (102)), while the reception path (450) may be described as being implemented in a UE (e.g., UE (116)). However, it will be understood that the reception path (450) may be implemented in a gNB, and the transmission path (400) may be implemented in a UE. In some embodiments, the transmission path (400) and / or the reception path (450) are configured to enable superimposed OFDM waveforms for low-power signals as described in embodiments of the present disclosure.

[0054] As illustrated in FIG. 4a, the transmission path (400) includes a channel coding and modulation block (405), a serial-to-parallel (S-to-P) block (410), an inverse Fast Fourier Transform (IFFT) block of size N (415), a parallel-to-serial (P-to-S) block (420), a cyclic prefix addition block (425), and an up converter (UC) (430). The reception path (450) includes a down converter (DC) (455), a cyclic prefix removal block (460), a serial-to-parallel (S-to-P) block (465), a Fast Fourier Transform (FFT) block of size N (470), a parallel-to-serial (P-to-S) block (475), and a channel decoding and demodulation block (480).

[0055] In the transmission path (400), the channel coding and modulation block (405) receives a set of information bits, applies coding (e.g., LDPC (low-density parity check) coding), and modulates input bits (e.g., QPSK (Quadrature Phase Shift Keying) or QAM (Quadrature Amplitude Modulation)) to generate a series of frequency-domain modulation symbols. The serial-parallel block (410) converts the serially modulated symbols into parallel data (e.g., demultiplexes) to generate N parallel symbol streams, where N is the IFFT / FFT size used in the gNB and UE. The size N IFFT block (415) performs IFFT operations on the N parallel symbol streams to generate time-domain output signals. The parallel-to-serial block (420) converts (e.g., multiplexes) parallel time domain output symbols from the size N IFFT block (415) to generate a serial time domain signal. The cyclic prefix addition block (425) inserts a cyclic prefix into the time domain signal. The upconverter (430) modulates the output of the cyclic prefix addition block (425) to an RF frequency for transmission over a wireless channel (e.g., upconverting). The signal may also be filtered in the baseband before being converted to an RF frequency.

[0056] As illustrated in FIG. 4b, the downconverter (455) downconverts the received signal to a baseband frequency, and the cyclic prefix removal block (460) removes the cyclic prefix to generate a serial time domain baseband signal. The serial-to-parallel block (465) converts the time domain baseband signal into a parallel time domain signal. The size N FFT block (470) performs an FFT algorithm to generate N parallel frequency domain signals. The parallel-to-serial block (475) converts the parallel frequency domain signals into a sequence of modulated data symbols. The channel decoding and demodulation block (480) demodulates and decodes the modulated symbols to restore the original input data stream.

[0057] Each of the gNBs (101-103) can implement a transmission path (400) similar to transmitting to the UE (111-116) in the downlink and a reception path (450) similar to receiving from the UE (111-116) in the uplink. Likewise, each of the UEs (111-116) can implement a transmission path (400) for transmitting to the gNB (101-103) in the uplink and a reception path (450) for receiving from the gNB (101-103) in the downlink.

[0058] Each component of FIGS. 4a and FIGS. 4b may be implemented using only hardware or a combination of hardware and software / firmware. As a specific example, at least some of the components of FIGS. 4a and FIGS. 4b may be implemented in software, but other components may be implemented by configurable hardware or a combination of software and configurable hardware. For example, the FFT block (470) and the IFFT block (415) may be implemented as configurable software algorithms, wherein the value of size N may be modified depending on the implementation.

[0059] Additionally, although FFT and IFFT have been described as being used, this is merely an example and should not be construed as limiting the scope of the disclosure. Other types of transforms, such as the Discrete Fourier Transform (DFT) and Inverse Discrete Fourier Transform (IDFT) functions, may be used. It will be understood that for DFT and IDFT functions, the values ​​of the N variables can be any integers (e.g., 1, 2, 3, 4, etc.), whereas for FFT and IFFT functions, the values ​​of the N variables can be any integers that are powers of 2 (i.e., 1, 2, 4, 8, 16, etc.).

[0060] Although FIGS. 4a and 4b illustrate examples of wireless transmission and reception paths (400 and 450), respectively, various modifications may be made to FIGS. 4a and 4b. For example, various components of FIGS. 4a and 4b may be combined, further subdivided, or omitted, and additional components may be added as needed. FIGS. 4a and 4b are intended to illustrate examples of types of transmission and reception paths that may be used in a wireless network. Other suitable architectures may be used to support wireless communications in a wireless network.

[0061] NR supports Discontinuous Receive (DRX) for UEs in RRC_IDLE / RRC_INACTIVE mode or RRC_CONNECTED mode, thereby allowing UEs to stop receiving signals or channels during inactive periods within a DRX cycle and reduce power consumption. In Rel-16, DRX improvements for RRC_CONNECTED mode (e.g., C-DRX) were introduced, where additional power savings could be achieved by using a new DCI format to allow UEs to skip ON durations within a C-DRX cycle. In Rel-17, DRX improvements for RRC_IDLE / RRC_INACTIVE mode (e.g., I-DRX) were introduced, where additional power savings could be achieved by using Early Paging Indication (PEI) to allow UEs to skip paging occations.

[0062] However, the UE still needs to wake up frequently to monitor the new DCI format or PEI, and consequently, the UE's radio cannot be completely turned off for long durations. To avoid this situation and obtain additional power saving benefits, an additional receiver radio is being considered, where the additional receiver radio can be used to monitor a specific set of signals with very low power consumption, and the main receiver radio can be turned off or operate at very low power for long durations.

[0063] The present disclosure focuses on superimposed OFDM-based waveform(s) of low-power signals that can be received at low power, for example, the waveform can be received using an additional receiver radio.

[0064] Additionally, the present disclosure focuses on the design of a sequence of low-power signals that can be received at low power, and, for example, the waveform can be received using an additional receiver radio.

[0065] In one example, low-power signals may include a low-power wake-up signal, for instance, a low-power signal to wake up a main receiver.

[0066] In another example, low-power signals may include low-power synchronization signals, such as low-power signals for synchronization with a low-power receiver.

[0067] In another example, low-power signals may include a low-power wake-up signal (LP-WUS), for example, a low-power signal for waking up a main receiver. At least one of the examples of the present disclosure may be used to generate an LP-WUS sequence.

[0068] In another example, low-power signals may include a low-power synchronization signal (LP-SS), for example, a low-power signal for synchronization with a low-power receiver. At least one of the examples of the present disclosure may be used for generating an LP-SS sequence.

[0069] The present disclosure focuses on superimposed OFDM-based waveforms for low-power signal(s). More specifically, the following embodiments are included in the present disclosure:

[0070] ● Generation of signals with superimposed OFDM-based waveform(s)

[0071] ○ Type 1: Overlapping OFDM-based waveform(s) applied to a low-power signal that may span one or more OFDM symbols

[0072] ○ Type 2: Overlapping OFDM-based waveform(s) applied to a single OFDM symbol

[0073] ○ Type 3: Overlapping OFDM-based waveform(s) applied to segments within a single OFDM symbol

[0074] ● Information carried by superimposed OFDM-based waveform(s)

[0075] ● Exemplary UE procedure for using superimposed OFDM-based waveform(s)

[0076] Additionally, the present disclosure focuses on the design of sequences of superimposed OFDM waveform(s) used to generate low-power signals. More specifically, the following aspects are included in the present disclosure:

[0077] ● M-sequence-based signal generation

[0078] ● Gold-sequence based signal generation

[0079] ● Pseudo-random-sequence based signal generation

[0080] ● Low-PAPR (peak-to-average-power ratio)-sequence-based signal generation

[0081] ● Exemplary UE Procedure for Sequence Generation

[0082] The aspects, features, and advantages of the present disclosure are readily apparent from the following detailed description by simply illustrating a number of specific embodiments and implementations, including the best mode considered for carrying out the present disclosure. The present disclosure also allows for other and different embodiments, and some details thereof may be modified in various obvious respects without departing from the spirit and scope of the present disclosure. Accordingly, the drawings and description should be considered illustrative in nature and not restrictive. The present disclosure is illustrated in the drawings of the accompanying drawings as an example, not a limitation.

[0083] Although the following exemplary descriptions and embodiments assume Orthogonal Frequency Division Multiplexing (OFDM) or Orthogonal Frequency Division Multiple Access (OFDMA), the present disclosure may be extended to other OFDM-based transmit waveforms or multiple access schemes such as filtered OFDM (F-OFDM).

[0084] The present disclosure encompasses various components that can be used together or in combination with each other, or can operate as standalone modes.

[0085] Where the low-power signal(s) include multiple types of signals, each signal type may follow the examples in the present disclosure jointly or individually.

[0086] One component provided by the present disclosure relates to signal generation having superimposed OFDM waveforms.

[0087] In one embodiment, a low-power signal can be generated based on an OOK-based waveform and additionally based on a superimposed OFDM-based waveform.

[0088] In one example, a low-power signal from T to T+d as a time instance is It can be generated according to, where It is generated based on an OOK-based waveform, and It is generated based on an OFDM-based waveform.

[0089] In another example, a low-power signal from time instances T through T+d can be generated according to the following:

[0090] ,

[0091] Here, It is generated based on OOK-based waveforms (e.g., The value of can correspond to an ON value (e.g., 1 or a non-zero value based on transmission power) or an OFF value (e.g., 0), It is generated based on an OFDM-based waveform.

[0092] FIGS. 5 through 7 respectively illustrate drawings (500, 600, and 700) of OFDM-based waveforms superimposed on OOK-based waveforms according to embodiments of the present disclosure. For example, the waveforms of drawings (500, 600, or 700) may be implemented by the gNB (102) of FIG. 1. These examples are for illustrative purposes only, and other embodiments may be used without departing from the scope of the present disclosure.

[0093] In one consideration of the examples of the present embodiment, as illustrated in FIG. 5, time instances T through T+d may correspond to ODFM symbols (e.g., no CP), and the overlapping OFDM sequence is applied to the entire OFDM symbol (e.g., if the OFDM symbol includes multiple segments, the overlapping OFDM sequence is applied to the multiple segments).

[0094] In other considerations of the examples of the present embodiment, as illustrated in FIG. 6, time instances T through T+d may correspond to segments within an ODFM symbol (e.g., no CP), wherein the OFDM symbol may include one or more segments (e.g., segments may correspond to ON or OFF values), and a superimposed OFDM sequence is applied to each segment (e.g., if the OFDM symbol includes more segments, the superimposed OFDM sequence is applied to each of the more segments).

[0095] In another consideration of the examples of the present embodiment, as illustrated in FIG. 6, time instances T through T+Td may correspond to one or more ODFM symbols (e.g., OFDM symbols spanning a low-power signal), and an overlapping OFDM sequence is applied to one or more OFDM symbols.

[0096] In another consideration of the examples of the present embodiment, When generating superimposed ODFM-based waveforms (e.g., Whether to apply ) can be determined based on upper-level parameters. For example, if upper-level parameters are provided, the superimposed ODFM-based waveform (e.g., ) is applied according to the examples of the present disclosure to generate based on an ODFM-based waveform; and where upper-level parameters are not provided, an overlaid ODFM-based waveform (e.g., ) does not apply (e.g., or equivalently Or apply a constant value based on transmission power).

[0097] In another consideration of the examples of the present embodiment, When generating superimposed ODFM-based waveforms (e.g., Whether to apply ) can be determined by UE capabilities. For example, the UE may apply superimposed OFDM-based waveforms (e.g., It can report whether it has the ability to decode the information contained in ). In another example, the UE uses a superimposed ODFM-based waveform (e.g., Whether or not to use ) may be provided in the UE support information.

[0098] In another consideration of the examples of the present embodiment, When generating OOK-based waveforms (e.g., Whether to apply ) can be determined based on upper-level parameters. For example, if upper-level parameters are provided, OOK-based waveforms (e.g., It is generated based on an OOK-based waveform with ) applied, and if upper-layer parameters are not provided, This does not apply (e.g., or equivalently Or apply a constant value based on transmission power).

[0099] In another consideration of the examples of the present embodiment, OOK-based waveform at the time of generation (e.g., Whether to apply ) can be determined by the UE's capabilities. For example, the UE uses OOK-based waveforms (e.g., It can report whether it has the ability to decode the information contained in ). In another example, the UE [can] OOK-based waveform (e.g., Whether or not to prefer the use of ) may be provided in the UE support information.

[0100] In another consideration of the examples of the present embodiment, the low-power signals may include a low-power wake-up signal (LP-WUS), e.g., a low-power signal for waking up a main receiver. In one additional example, the LP-WUS may be associated with a low-power synchronization signal at each of its transmissions, wherein the low-power synchronization signal is not periodic.

[0101] In another consideration of the examples of the present embodiment, the low-power signals may include a low-power synchronization signal (LP-SS), for example, a low-power signal for synchronization with a low-power receiver, and / or, for example, this LP-SS is transmitted periodically.

[0102] Another component provided by the present disclosure relates to information carried by a superimposed OFDM-based waveform.

[0103] In one embodiment, the superimposed OFDM-based waveform can carry information.

[0104] As an additional consideration, information carried by the superimposed OFDM-based waveform may be explicitly carried by the sequence generating the superimposed OFDM-based waveform (e.g., by initial conditions, cyclic shifts, phase shifts, etc.), implicitly carried by the position of the sequence in the time and / or frequency domain, or carried by a combination of these two methods (e.g., explicit and implicit methods).

[0105] In one example, an overlapping OFDM-based waveform (e.g., as in the examples of the present disclosure) ) can be applied to OFDM symbols over which a low-power signal spans (e.g., as illustrated in FIG. 7), and information carried by an OFDM-based waveform (e.g., (indicated as ) is information returned by an OOK-based waveform (e.g., It may be identical to (indicated as), for example, am.

[0106] In another example, a superimposed OFDM-based waveform (e.g., as in the examples of the present disclosure) ) can be applied to OFDM symbols over which a low-power signal spans (e.g., as illustrated in FIG. 7), and information carried by the OFDM-based waveform (e.g., as (indicated as ) is information returned by an OOK-based waveform (e.g., It may be a subset of (indicated as), am.

[0107] In another example, a superimposed OFDM-based waveform (e.g., as in the examples of the present disclosure) ) can be applied to a single OFDM symbol included in OFDM symbols spanning a low-power signal (e.g., as illustrated in FIG. 5), and information carried by an OFDM-based waveform (e.g., (indicated as ) excludes the OFDM symbol index (for example, the OFDM symbol index is or (not counted in), information returned by OOK-based waveforms (e.g., It may be identical to (indicated as), for example, am.

[0108] ● In one sub-example, if there are multiple OFDM symbols spanned by a low-power signal, the superimposed OFDM-based waveform may differ across the multiple OFDM symbols. For example, the sequence generated across different OFDM symbols spanned by the low-power signal may depend on the OFDM symbol index.

[0109] In another example, a superimposed OFDM-based waveform (e.g., as in the examples of the present disclosure) ) can be applied to a single OFDM symbol included in OFDM symbols spanning a low-power signal (e.g., as illustrated in FIG. 5), and information carried by an OFDM-based waveform (e.g., (indicated as ) is information returned by an OOK-based waveform (e.g., It may be a subset of (indicated as), for example, am.

[0110] ● In one sub-example, if there are multiple OFDM symbols over which a low-power signal spans, the superimposed OFDM-based waveform can be identical across the multiple OFDM symbols.

[0111] ● In another sub-example, when there are multiple OFDM symbols spanned by a low-power signal, the superimposed OFDM-based waveform may differ across the multiple OFDM symbols. For example, the sequence generated across different OFDM symbols spanned by the low-power signal may depend on the OFDM symbol index.

[0112] In another example, a superimposed OFDM-based waveform (e.g., as in the examples of the present disclosure) ) can be applied to a single OFDM symbol included in OFDM symbols spanning a low-power signal (e.g., as illustrated in FIG. 5), and information carried by an OFDM-based waveform (e.g., (indicated as ) excludes the OFDM symbol index (for example, the OFDM symbol index is or (not counted in), information returned by OOK-based waveforms (e.g., It may be a subset of (indicated as), am.

[0113] ● In one sub-example, if there are multiple OFDM symbols spanned by a low-power signal, the superimposed OFDM-based waveform may differ across the multiple OFDM symbols. For example, the sequence generated across different OFDM symbols spanned by the low-power signal may depend on the OFDM symbol index.

[0114] For example, superimposed OFDM-based waveforms (e.g., as in the examples of the present disclosure). ) can be applied to a segment within an OFDM symbol (e.g., corresponding to an ON or OFF value in an OOK waveform) included in OFDM symbols over which a low-power signal spans (e.g., as illustrated in FIG. 6), and to information carried by an OFDM-based waveform (e.g., (indicated as ) is information returned by an OOK-based waveform (e.g., It may be identical to (indicated as), for example, am.

[0115] ● In one sub-example, if there are multiple segments within a single OFDM symbol, the overlapping OFDM-based waveform can be identical across multiple segments.

[0116] ● In another sub-example, when there are multiple segments within a single OFDM symbol, the overlapping OFDM-based waveform may differ across the multiple segments. For example, the sequence generated in different segments may depend on the segment index and / or OFDM symbol index.

[0117] In another example, a superimposed OFDM-based waveform (e.g., as in the examples of the present disclosure) ) can be applied to a segment within an OFDM symbol (e.g., corresponding to an ON or OFF value in an OOK waveform) included in OFDM symbols over which a low-power signal spans (e.g., as illustrated in FIG. 6), and information carried by an OFDM-based waveform (e.g., (indicated as ) excludes OFDM symbol index and / or segment index (e.g., OFDM symbol index and / or segment index is or (not counted in), information returned by the OOK-based waveform (e.g., It may be identical to (indicated as), for example, am.

[0118] ● In one sub-example, if there are multiple segments within a single OFDM symbol, the overlapping OFDM-based waveform may differ across the multiple segments. For example, the sequence generated in different segments may depend on the segment index and / or OFDM symbol index.

[0119] In another example, a superimposed OFDM-based waveform (e.g., as in the examples of the present disclosure) ) can be applied to a segment within an OFDM symbol (e.g., corresponding to an ON or OFF value in an OOK waveform) included in OFDM symbols over which a low-power signal spans (e.g., as illustrated in FIG. 6), and to information carried by an OFDM-based waveform (e.g., (indicated as ) is information returned by an OOK-based waveform (e.g., It may be a subset of (indicated as), for example, am.

[0120] ● In one sub-example, if there are multiple segments within a single OFDM symbol, the overlapping OFDM-based waveform can be identical across multiple segments.

[0121] ● In another sub-example, when there are multiple segments within a single OFDM symbol, the overlapping OFDM-based waveform may differ across the multiple segments. For example, the sequence generated in different segments may depend on the segment index and / or OFDM symbol index.

[0122] ● In another sub-example, the combination of information carried by segments within all OFDM symbols spanning the low-power signal may be identical to the information carried by the OOK-based waveform. For example, the combination of information carried by these segments does not include a segment index and / or an OFDM symbol index. The UE can obtain the same information by detection from the OOK-based waveform of the low-power signal and by detection from the OFDM-based waveform in the segments of the low-power signal.

[0123] In another example, a superimposed OFDM-based waveform (e.g., as in the examples of the present disclosure) ) can be applied to a segment within an OFDM symbol (e.g., corresponding to an ON or OFF value in an OOK waveform) included in OFDM symbols over which a low-power signal spans (e.g., as illustrated in FIG. 6), and to information carried by an OFDM-based waveform (e.g., (indicated as ) excludes OFDM symbol index and / or segment index (e.g., OFDM symbol index and / or segment index is or Information returned by an OOK-based waveform (not counted in) (e.g., It may be a subset of (indicated as), for example, am.

[0124] ● In one sub-example, if there are multiple segments within a single OFDM symbol, the overlapping OFDM-based waveform may differ across the multiple segments. For example, the sequence generated in different segments may depend on the segment index and / or OFDM symbol index.

[0125] ● In another sub-example, the combination of information carried by segments within all OFDM symbols spanning the low-power signal may be identical to the information carried by the OOK-based waveform. For example, the combination of information carried by these segments does not include a segment index and / or an OFDM symbol index. The UE can obtain the same information by detection from the OOK-based waveform of the low-power signal and by detection from the OFDM-based waveform in the segments of the low-power signal.

[0126] Other components provided by the present disclosure relate to exemplary UE procedures.

[0127] FIG. 8 illustrates an exemplary method (800) performed by a UE in a wireless communication system according to embodiments of the present disclosure. The method (800) of FIG. 8 may be performed by any of the UEs (111-116) of FIG. 1, such as the UE (116) of FIG. 3, and the corresponding method may be performed by any of the gNBs (101-103) of FIG. 1, such as the gNB (102) of FIG. 2. The method (800) is for illustrative purposes only, and other embodiments may be used without departing from the scope of the present disclosure.

[0128] In one embodiment, as illustrated in FIG. 8, an exemplary method (800) is for receiving a superimposed OFDM-based waveform. The method (800) begins with the UE receiving a low-power signal (810). Then, the UE determines the superimposed OFDM-based waveform contained in the low-power signal (820). Then, the UE determines the information carried by the superimposed OFDM-based waveform (830).

[0129] Another component provided by the present disclosure relates to M-sequence-based signal generation.

[0130] In one embodiment, an overlapping OFDM-based waveform for a low-power signal can be generated based on an M-sequence.

[0131] In one example, sequence generation is performed in the frequency domain. For example, a BPSK modulated M-sequence is mapped to a continuous number (e.g., L) of subcarriers in the frequency domain, and then an IFFT operation is performed to generate an overlapping OFDM-based waveform in the time domain.

[0132] In another example, sequence generation takes place in the time domain. For example, a BPSK modulated M-sequence is mapped to a continuous number (e.g., L) of samples in the time domain.

[0133] In one example, a BPSK-modulated M-sequence can be given as follows:

[0134]

[0135] In one example, when L=127, the corresponding M-sequence The generation method can be determined as one of the methods in Table 1.

[0136] Table 1: Exemplary M-sequence generation method of length 127

[0137]

[0138] In another example, when L=255, the corresponding M-sequence The generation method can be determined as one of the methods in Table 2.

[0139] Table 2: Exemplary M-sequence generation method of length 255

[0140]

[0141] In one example, an M-sequence (e.g., The cyclic shift applied to ) can be fixed at 0.

[0142] In another example, the cyclic shift can be determined based on information carried by an overlapping OFDM-based waveform.

[0143] In one example, the initial condition can be determined based on information carried by an overlapping OFDM-based waveform.

[0144] In another example, the initial conditions can be fixed. In one example, for L=127, the M-sequence The initial condition for generating can follow x(6:0) = [0 0 0 0 0 0 1]. In another example, for L=255, the M-sequence The initial condition for generating can be x(7:0) = [0 0 0 0 0 0 0 1].

[0145] Another component provided by the present disclosure relates to gold-sequence-based signal generation.

[0146] In one embodiment, a superimposed OFDM-based waveform for a low-power signal can be generated based on a gold sequence.

[0147] In one example, sequence generation can be performed in the frequency domain. For example, a BPSK modulated gold sequence is mapped to a continuous number (e.g., L) of subcarriers in the frequency domain, and then an IFFT operation is performed to generate a superimposed OFDM-based waveform.

[0148] In another example, sequence generation can be performed in the time domain. For example, a BPSK modulated gold sequence is mapped to a continuous number (e.g., L) of samples in the time domain to generate an overlapping OFDM-based waveform.

[0149] In one example, a BPSK-modulated gold sequence can be given as follows:

[0150]

[0151] In one example, when L=127, the corresponding M-sequence The generation method can be determined as the first generation method among Table 1, and the corresponding M-sequence The generation method can be determined as the second generation method among Table 1, where the first generation method and the second generation method are different.

[0152] In another example, when L=255, the corresponding M-sequence The generation method can be determined as the first generation method among Table 2, and the corresponding M-sequence The generation method can be determined as the second generation method among Table 2, where the first generation method and the second generation method are different.

[0153] In one example, M-sequence The cyclic shift applied to (e.g., m0) can be fixed at 0.

[0154] In another example, M-sequence The cyclic shift applied to (e.g., m0) can be determined based on the information or part of the information carried by the superimposed OFDM-based waveform.

[0155] In one example, M-sequence The cyclic shift applied to (e.g., m1) can be fixed at 0.

[0156] In another example, M-sequence The cyclic shift applied to (e.g., m1) can be determined based on the information or part of the information carried by the superimposed OFDM-based waveform.

[0157] In one example, M-sequence The initial conditions for can be determined based on information or a portion of information carried by the superimposed OFDM-based waveform.

[0158] In another example, M-sequence The initial conditions for can be fixed. In one example, when L=127, the M-sequence The initial condition for generating can follow x0(6:0) = [0 0 0 0 0 0 1]. In another example, when L=255, the M-sequence The initial condition for generating can be x0(7:0) = [0 0 0 0 0 0 0 1].

[0159] In one example, M-sequence The initial conditions for can be determined based on information or a portion of information carried by the superimposed OFDM-based waveform.

[0160] In another example, M-sequence The initial conditions for can be fixed. For example, when L=127, the M-sequence The initial condition for generating can follow x1(6:0) = [0 0 0 0 0 0 1]. In another example, when L=255, the M-sequence The initial condition for generating can be x1(7:0) = [0 0 0 0 0 0 0 1].

[0161] Another component provided by the present disclosure relates to pseudo-random-sequence-based signal generation.

[0162] In one embodiment, a superimposed OFDM-based waveform for a low-power signal can be generated based on a pseudo-random-sequence (or PN-sequence).

[0163] In one example, sequence generation can be performed in the frequency domain. For example, a QPSK-modulated pseudo-random sequence can be mapped to multiple (e.g., L) subcarriers in the frequency domain, and then an IFFT operation can be performed to generate an overlapping OFDM-based waveform.

[0164] In another example, sequence generation can take place in the time domain. For instance, a QPSK-modulated pseudo-random sequence is mapped to multiple (e.g., L) samples in the time domain to generate an overlapping OFDM-based waveform.

[0165] In one example, a QPSK-modulated pseudo-random sequence can be given as follows:

[0166]

[0167] In one example, initial condition c int It can be determined based on information or a portion of information carried by a superimposed OFDM-based waveform.

[0168] Another component provided by the present disclosure relates to signal generation based on a low-PAPR sequence (e.g., also known as a Zadoff-Chu sequence or ZC sequence).

[0169] In one embodiment, a superimposed OFDM-based waveform for a low-power signal can be generated based on a low-PAPR sequence (or ZC sequence).

[0170] In one example, sequence generation can be performed in the frequency domain. For instance, a low-PAPR sequence is mapped to multiple (e.g., L) subcarriers in the frequency domain, and then an IFFT operation is performed to generate an overlaid OFDM-based waveform.

[0171] In another example, sequence generation can take place in the time domain. For instance, a low-PAPR sequence is mapped to multiple (e.g., L) samples in the time domain to generate an overlapping OFDM-based waveform.

[0172] In one example, the low-PAPR sequence can be given by:

[0173] or Here .

[0174] In one example, or q may be determined based on information or a portion of information carried by a superimposed OFDM-based waveform, and / or L is, for example, It is the length of the ZC-sequence that can be given by the largest prime number satisfying , where is the number of RBs used for low-power signals in the frequency domain, and M is the number of segments within one OFDM symbol for the OOK waveform.

[0175] Other components provided by the present disclosure relate to other exemplary UE procedures.

[0176] FIG. 9 illustrates an exemplary method (900) performed by a UE in a wireless communication system according to embodiments of the present disclosure. The method (900) of FIG. 9 may be performed by any of the UEs (111-116) of FIG. 1, such as the UE (116) of FIG. 3, and the corresponding method may be performed by any of the gNBs (101-103) of FIG. 1, such as the gNB (102) of FIG. 2. The method (900) is for illustrative purposes only, and other embodiments may be used without departing from the scope of the present disclosure.

[0177] In one embodiment, as illustrated in FIG. 9, an exemplary method (900) is for receiving a low-power signal based on a sequence. The method (900) begins with the UE determining information to be returned by the low-power signal (910). Then, the UE determines a sequence for generating the low-power signal based on this information (920). Then, the UE receives the low-power signal based on this sequence (930).

[0178] Any of the above variations may be used independently or in combination with at least one other variation. The above flowcharts illustrate exemplary methods that may be implemented in accordance with the principles of the present disclosure, and various changes and modifications may be made to the methods illustrated in the flowcharts herein. For example, although illustrated as a series of steps, the various steps in each figure may overlap, occur in parallel, occur in a different order, or occur multiple times. In other examples, steps may be omitted or replaced with other steps.

[0179] Although the drawings illustrate various examples of user terminals, various modifications to the drawings may be made. For example, a user terminal may include any number of each component in any suitable arrangement. In general, the drawings do not limit the scope of the present disclosure to specific configuration(s). Furthermore, while the drawings illustrate operating environments in which the various user terminal functions disclosed in this patent document may be used, these functions may be used in any other suitable system.

[0180] Although the present disclosure has been described by exemplary embodiments, those skilled in the art may propose various changes and modifications. The present disclosure is intended to include such changes and modifications that fall within the scope of the appended claims. Nothing in this application shall be construed as indicating that any particular element, step, or function is an essential element to be included in the claims. The scope of the subject matter is defined by the claims.

Claims

Claim 1 A user equipment (UE) in a communication system comprising: a transceiver; and a processor operably coupled to said transceiver, wherein the processor identifies a set of orthogonal frequency division multiplexing (OFDM) symbols for a low-power signal, wherein each OFDM symbol comprises one or more segments, determines an on-off-key (OOK) waveform for said low-power signal, wherein each segment corresponds to an ON waveform or an OFF waveform, determines a set of superimposed OFDM waveforms, wherein each superimposed OFDM waveform is applied to said segment when the segment corresponds to an ON waveform, and is configured to receive said low-power signal based on said OOK waveform and said set of superimposed OFDM waveforms. Claim 2 A user terminal according to claim 1, wherein the low power signal is one of a low power synchronization signal (LP-SS) or a low power wake-up signal (LP-WUS). Claim 3 A user terminal according to claim 1, wherein the information carried by the superimposed OFDM waveform within the set of superimposed OFDM waveforms is a subset of the information carried by the OOK waveform. Claim 4 A user terminal according to claim 1, wherein the information carried by the first superimposed OFDM waveform within the set of superimposed OFDM waveforms is different from the information carried by the second superimposed OFDM waveform within the set of superimposed OFDM waveforms when the first superimposed OFDM waveform and the second superimposed OFDM waveform correspond to different segments within the OFDM symbol. Claim 5 In claim 1, the user terminal, wherein the information returned by the set of the superimposed OFDM waveforms is the same as the information returned by the OOK waveform. Claim 6 A user terminal according to claim 1, wherein the superimposed OFDM waveform within the set of superimposed OFDM waveforms is generated in the frequency domain and mapped to a plurality of subcarriers in the frequency domain. Claim 7 A user terminal according to claim 1, wherein the superimposed OFDM waveform within the set of superimposed OFDM waveforms is generated according to a low PAPR (peak-to-average-power ratio) sequence. Claim 8 A base station (BS) in a communication system comprising: a transceiver; and a processor operably coupled to said transceiver, wherein the processor identifies a set of orthogonal frequency division multiplexing (OFDM) symbols for a low-power signal, wherein each OFDM symbol comprises one or more segments; determines an on-off-key (OOK) waveform for said low-power signal, wherein each segment corresponds to an ON waveform or an OFF waveform; determines a set of superimposed OFDM waveforms, wherein each superimposed OFDM waveform is applied to said segment when the segment corresponds to an ON waveform; and is configured to transmit said low-power signal based on said OOK waveform and said set of superimposed OFDM waveforms. Claim 9 In paragraph 8, the base station, wherein the low power signal is one of a low power synchronization signal (LP-SS) or a low power wake-up signal (LP-WUS). Claim 10 In paragraph 8, the base station, wherein the information carried by the superimposed OFDM waveform within the set of superimposed OFDM waveforms is a subset of the information carried by the OOK waveform. Claim 11 In claim 8, the information carried by the first superimposed OFDM waveform within the set of superimposed OFDM waveforms is different from the information carried by the second superimposed OFDM waveform within the set of superimposed OFDM waveforms when the first superimposed OFDM waveform and the second superimposed OFDM waveform correspond to different segments within the OFDM symbol. Claim 12 In paragraph 8, the base station, wherein the information carried by the set of superimposed OFDM waveforms is the same as the information carried by the OOK waveform. Claim 13 In claim 8, the superimposed OFDM waveform within the set of superimposed OFDM waveforms is generated in the frequency domain and mapped to a plurality of subcarriers in the frequency domain, a base station. Claim 14 A method performed by a user equipment (UE) in a communication system, comprising: identifying a set of orthogonal frequency division multiplexing (OFDM) symbols for a low-power signal, wherein each OFDM symbol comprises one or more segments; determining an on-off-key (OOK) waveform for the low-power signal, wherein each segment corresponds to an ON waveform or an OFF waveform; determining a set of superimposed OFDM waveforms, wherein each superimposed OFDM waveform is applied to the segment when the segment corresponds to an ON waveform; and receiving the low-power signal based on the OOK waveform and the set of superimposed OFDM waveforms. Claim 15 A method performed by a base station (BS) in a communication system, comprising: identifying a set of orthogonal frequency division multiplexing (OFDM) symbols for a low-power signal, wherein each OFDM symbol comprises one or more segments; determining an on-off-key (OOK) waveform for the low-power signal, wherein each segment corresponds to an ON waveform or an OFF waveform; determining a set of superimposed OFDM waveforms, wherein each superimposed OFDM waveform is applied to a segment when the segment corresponds to an ON waveform; and transmitting the low-power signal based on the OOK waveform and the set of superimposed OFDM waveforms.

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