CN117837257A - Method and apparatus for performing random access based on full duplex system in wireless communication system - Google Patents

Abstract

The present disclosure relates to 5G or 6G communication systems for supporting high data transmission rates. In the present disclosure, methods and apparatus for Random Access (RA) in a Full Duplex (FD) wireless communication system are provided. A method for transmitting a Random Access Channel (RACH) associated with an RA procedure includes: first information for a first parameter of a first RACH configuration associated with a first subset of time slots from a set of time slots on a cell, second information for a second parameter of a second RACH configuration associated with a second subset of time slots from the set of time slots on the cell, and third information for a condition are received. The method also includes determining whether a condition is valid for transmission in a time slot from a second subset of time slots, and transmitting RACH in a time slot based on the first RACH configuration when the condition is valid, and transmitting RACH in a time slot based on the second RACH configuration when the condition is not valid.

Description

Method and apparatus for performing random access based on full duplex system in wireless communication system

Technical Field

The present disclosure relates generally to wireless communication systems (or mobile communication systems), and more particularly, to Random Access (RA) in full-duplex (FD) systems (or full-duplex radios).

Background

The 5G mobile communication technology defines a wide frequency band, enabling high transmission rates and new services, and can be implemented not only in a "below 6 GHz" band such as 3.5GHz, but also in a "above 6 GHz" band called millimeter wave (mmWave) including 28GHz and 39 GHz. Further, in order to achieve a transmission rate 50 times faster than that of the 5G mobile communication technology and an ultra-low latency of one tenth of that of the 5G mobile communication technology, it has been considered to implement the 6G mobile communication technology (referred to as transcendental 5G system) in a terahertz band (e.g., 95GHz to 3THz band).

In the early stages of the development of 5G Mobile communication technology, in order to support services and meet performance requirements related to enhanced Mobile BroadBand (eMBB), ultra-reliable low latency communication (Ultra Reliable Low Latency Communications, URLLC), and large-scale Machine-type communication (emtc), standardization is underway with respect to the following technologies: beamforming and massive MIMO for reducing radio wave path loss and increasing radio wave transmission distance in millimeter waves, supporting dynamic operation of parameter sets (e.g., operating a plurality of subcarrier intervals) and slot formats for effectively utilizing millimeter wave resources, initial access techniques for supporting multi-beam transmission and broadband, definition and operation of BWP (bandwidth part), new channel coding methods such as LDPC (low density parity check) codes for mass data transmission and polarization codes for highly reliable transmission of control information, L2 preprocessing, and network slicing for providing a dedicated network dedicated to a specific service.

Currently, in view of services that the 5G mobile communication technology will support, discussions are being made about improvement and performance enhancement of the initial 5G mobile communication technology, and physical layer standards have existed about various technologies such as the following: V2X (vehicle versus everything) for assisting driving determination of an autonomous vehicle based on information sent by the vehicle about the position and status of the vehicle and for enhancing user convenience, NR-U (new radio unlicensed) for system operation meeting various regulatory-related requirements in unlicensed bands, NR UE power saving, non-terrestrial network (Non-Terrestrial Network, NTN), which is UE-satellite direct communication for providing coverage in areas where communication with the terrestrial network is unavailable, and positioning.

Further, in terms of air interface architecture/protocols, standardization is underway with respect to various technologies such as: industrial internet of things (Industrial Internet of Things, IIoT) for supporting new services through interworking and convergence with other industries, IAB (integrated access and backhaul) for providing nodes for network service area extension by supporting wireless backhaul links and access links in an integrated manner, mobility enhancements including conditional handover and DAPS (dual active protocol stack) handover, and two-step random access (2-step RACH of NR) for simplifying random access procedures. Standardization is also underway in terms of system architecture/services regarding various techniques: a 5G baseline architecture (e.g., service-based architecture or service-based interface) for combining network function virtualization (Network Functions Virtualization, NFV) and Software Defined Networking (SDN) technologies, and mobile edge computing (Mobile Edge Computing, MEC) for receiving services based on UE location.

With commercialization of the 5G mobile communication system, exponentially growing connected devices will be connected to the communication network, and thus, it is expected that enhanced functions and performance of the 5G mobile communication system and integrated operation of the connected devices will be necessary. For this reason, new studies related to the following technologies are planned: new researches on augmented Reality (XR) for effectively supporting AR (augmented Reality), VR (virtual Reality), MR (mixed Reality), etc. have been made by using 5G performance improvement and complexity reduction of artificial intelligence (Artificial Intelligence, AI) and Machine Learning (ML), AI service support, meta space service support, and unmanned aerial vehicle communication.

Further, such development of the 5G mobile communication system will be the basis for developing not only new waveforms for providing coverage in the terahertz band of the 6G mobile communication technology, multi-antenna transmission technologies such as full-dimensional MIMO (FD-MIMO), array antennas and massive antennas, metamaterial-based lenses and antennas for improving terahertz band signal coverage, high-dimensional spatial multiplexing technology using OAM (orbital angular momentum) and RIS (reconfigurable intelligent surface), but also full duplex technology for improving frequency efficiency of the 6G mobile communication technology and improving system network, AI-based communication technology for realizing system optimization by utilizing satellites and AI (artificial intelligence) from the design stage and internalizing end-to-end support functions, and next generation distributed computing technology for realizing a service of a complexity degree exceeding the UE operation capability limit by utilizing ultra-high performance communication and computing resources.

Disclosure of Invention

Solution scheme

The present disclosure relates to RA in FD systems.

In one embodiment, a method performed by a User Equipment (UE) for transmitting a Random Access Channel (RACH) associated with an RA procedure is provided. The method comprises the following steps: first information for a first parameter of a first RACH configuration associated with a first subset of time slots from a set of time slots on a cell, second information for a second parameter of a second RACH configuration associated with a second subset of time slots from the set of time slots on the cell, and third information for a condition are received. The method also includes determining whether the condition is valid for transmission in a time slot from the second subset of time slots, and when the condition is valid, transmitting RACH in a time slot based on the first RACH configuration, and when the condition is not valid, transmitting RACH in a time slot based on the second RACH configuration.

In another embodiment, a User Equipment (UE) for transmitting RACH associated with RA procedure is provided. The UE includes a transceiver configured to receive first information for a first parameter of a first RACH configuration associated with a first subset of time slots from a set of time slots on a cell, second information for a second parameter of a second RACH configuration associated with a second subset of time slots from the set of time slots on the cell, and third information for a condition. The UE also includes a processor operably coupled to the transceiver. The processor is configured to determine whether the condition is valid for transmission in a time slot from the second subset of time slots. The transceiver is further configured to transmit RACH in a time slot based on the first RACH configuration when the condition is valid and to transmit RACH in a time slot based on the second RACH configuration when the condition is not valid.

In yet another embodiment, a method performed by a base station is provided. The method comprises the following steps: transmitting first information for a first parameter of a first RACH configuration associated with a first subset of time slots from a set of time slots on a cell; transmitting second information for a second parameter of a second RACH configuration associated with a second subset of time slots from the set of time slots on the cell; transmitting third information for the condition; and for the RA procedure, receiving RACH in a slot based on the first RACH configuration when the condition is valid and receiving RACH in a slot based on the second RACH configuration when the condition is not valid.

In yet another embodiment, a base station is provided. The BS includes a transceiver configured to transmit first information for a first parameter of a first RACH configuration associated with a first subset of time slots from a set of time slots on a cell, transmit second information for a second parameter of a second RACH configuration associated with a second subset of time slots from the set of time slots on the cell, transmit third information for a condition, and receive RACH in a time slot based on the first RACH configuration when the condition is valid and RACH in a time slot based on the second RACH configuration when the condition is invalid for an RA procedure.

Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.

Advantageous effects

According to various embodiments of the present disclosure, a random access procedure may be effectively enhanced according to a full duplex system.

Drawings

For a more complete understanding of the present disclosure and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts:

fig. 1 illustrates an example wireless network according to an embodiment of this disclosure;

fig. 2 illustrates an example BS according to an embodiment of the present disclosure;

fig. 3 illustrates an example UE in accordance with an embodiment of the present disclosure;

fig. 4 and 5 illustrate example wireless transmit and receive paths according to embodiments of the present disclosure;

fig. 6 illustrates an example diagram of Physical Random Access Channel (PRACH) time and frequency domain allocations in accordance with an embodiment of the disclosure;

FIG. 7 illustrates an example diagram of an E/T/R/R/BI Media Access Control (MAC) subheader in accordance with an embodiment of the present disclosure;

fig. 8 illustrates an example diagram of an E/T/RAPID MAC subheader in accordance with an embodiment of the present disclosure;

fig. 9 shows an example diagram of a MAC Random Access Response (RAR) according to an embodiment of the present disclosure;

fig. 10 illustrates an example diagram of a Time Division Duplex (TDD) communication system according to an embodiment of the present disclosure;

Fig. 11 shows an example diagram of two example FD communication system configurations according to an embodiment of the present disclosure;

fig. 12 shows an exemplary diagram of RACH configuration in an FD communication system according to an embodiment of the present disclosure;

fig. 13 shows an example diagram of a PRACH preamble transmission sequence according to an embodiment of the disclosure;

fig. 14 illustrates an example method of a PRACH transmission processing chain according to an embodiment of the disclosure;

fig. 15 shows an example diagram of a PRACH preamble transmission sequence according to an embodiment of the disclosure;

fig. 16 illustrates an example method of a PRACH transmission processing chain according to an embodiment of the disclosure;

fig. 17 shows an example diagram of a PRACH preamble transmission backoff sequence according to an embodiment of the present disclosure;

fig. 18 illustrates an example method of PRACH transmission backoff processing chains in accordance with an embodiment of the present disclosure;

fig. 19 illustrates an example method of a PRACH parameter backoff processing chain according to an embodiment of the present disclosure;

fig. 20 illustrates an example method of determination of RA type in XDD or normal UL slots, according to an embodiment of the disclosure;

fig. 21 illustrates an example method of a backoff procedure from 2-step RACH to 4-step RACH in XDD and normal UL slots according to an embodiment of the present disclosure;

fig. 22 illustrates an example method of determining a RAR window size according to an embodiment of the present disclosure;

Fig. 23 shows a block diagram of a terminal (or UE) according to an embodiment of the disclosure; and

fig. 24 shows a block diagram of a base station according to an embodiment of the present disclosure.

Detailed Description

Before proceeding with the following detailed description, it may be advantageous to set forth definitions of certain words and phrases used in this patent document. The term "couple" and its derivatives refer to any direct or indirect communication between two or more elements, whether or not those elements are in physical contact with one another. The terms "transmit," "receive," and "communicate," and derivatives thereof, include direct and indirect communication. The terms "include" and "comprise," as well as derivatives thereof, mean inclusion without limitation. The term "or" is inclusive, meaning and/or. The phrase "associated with … …" and its derivatives refer to include, are included, are interconnected with … …, are involved, are connected to or are connected with … …, are coupled to or are coupled with … …, are communicable with … …, are cooperative with … …, are staggered, are juxtaposed, are proximate, are joined to or are joined with … …, have … … properties, have relationships with … … or with … …, or the like. The term "controller" refers to any device, system, or portion thereof that controls at least one operation. Such a controller may be implemented in hardware or a combination of hardware and software and/or firmware. The functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. When used with a list of items, at least one of the phrases ". Cndot.is meant that different combinations of one or more of the listed items may be used, and only one item in the list may be required. For example, "at least one of A, B and C" includes any combination of: A. b, C, A and B, A and C, B and C, and a and B and C.

Furthermore, the various functions described below may be implemented or supported by one or more computer programs, each of which is formed from computer readable program code and embodied in a computer readable medium. The terms "application" and "program" refer to one or more computer programs, software components, sets of instructions, procedures, functions, objects, classes, instances, related data, or a portion thereof adapted for implementation in a suitable computer readable program code. The phrase "computer readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer readable medium" includes any type of medium capable of being accessed by a computer, such as Read Only Memory (ROM), random Access Memory (RAM), a hard disk drive, a Compact Disc (CD), a Digital Video Disc (DVD), or any other type of memory. "non-transitory" computer-readable media do not include wired, wireless, optical, or other communication links that transmit transitory electrical or other signals. Non-transitory computer readable media include media that can permanently store data and media that can store data and be later overwritten, such as rewritable optical disks or erasable storage devices.

Other definitions for certain words and phrases are provided throughout this patent document. Those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior as well as future uses of such defined words and phrases.

Figures 1 through 24, discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will appreciate that the principles of the present disclosure may be implemented in any suitably arranged system or device.

The following documents are incorporated by reference into the present disclosure as if fully set forth herein: third generation partnership project (3 GPP) Technical Specification (TS) 38.211v16.6.0, "NR; physical channel and modulation "(REF 1); 3GPP TS 38.212 v16.6.0, "NR; multiplexing and channel coding "(REF 2); 3GPP TS 38.213 v16.6.0, "NR; a physical layer program for control "(REF 3); 3GPP TS 38.214 v16.6.0, "NR; physical layer program for data "(REF 4); 3GPP TS 38.321 v16.5.0, "NR; medium Access Control (MAC) protocol specification "(REF 5); 3GPP TS 38.331 v16.5.0, "NR; radio Resource Control (RRC) protocol specification "(REF 6); and 3GPP TS 38.133 v16.8.0, "NR; requirements for supporting radio resource management "(REF 7).

In order to meet the increasing demand for wireless data services since the deployment of fourth generation (4G) communication systems, efforts have been made to develop and deploy improved fifth generation (5G) or pre-5G/NR communication systems. Thus, a 5G or pre-5G communication system is also referred to as a "super 4G network" or a "Long Term Evolution (LTE) after-system.

A 5G communication system is considered to be implemented in a higher frequency (mmWave) band (e.g., 28GHz or 60GHz band) in order to achieve a higher data rate, or in a lower frequency band (e.g., 6 GHz) in order to achieve robust coverage and mobility support. In order to reduce propagation loss of radio waves and increase transmission distance, beamforming, massive Multiple Input Multiple Output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, massive antenna techniques are discussed in 5G communication systems.

Further, in the 5G communication system, development of system network improvement is underway based on advanced small cells, cloud Radio Access Network (RAN) ultra dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, cooperative communication, coordinated multipoint (CoMP), receiving end interference cancellation, and the like.

The discussion of the 5G system and the frequency bands associated therewith is for reference as certain embodiments of the present disclosure may be implemented in a 5G system. However, the present disclosure is not limited to 5G systems or frequency bands associated therewith, and embodiments of the present disclosure may be used in connection with any frequency band. For example, aspects of the present disclosure may also be applied to 5G communication systems, 6G, or even deployments that may use later versions of the terahertz (THz) frequency band.

Depending on the network type, the term "base station" (BS) may refer to any component (or collection of components) configured to provide wireless access to a network, such as a Transmission Point (TP), a Transmission Reception Point (TRP), an enhanced base station (eNodeB or eNB), a gNB, a macrocell, a femtocell, a WiFi Access Point (AP), a satellite, or other wireless-enabled device. The base station may provide wireless access according to one or more wireless communication protocols (e.g., 5G 3GPP New radio interface/Access (NR), LTE-advanced (LTE-A), high Speed Packet Access (HSPA), wi-Fi 802.11a/b/g/n/ac, etc.). The terms "BS," "gNB," and "TRP" may be used interchangeably in this disclosure to refer to network infrastructure components that provide wireless access to remote terminals. Furthermore, the term "user equipment" (UE) may refer to any component, such as a terminal, mobile station, subscriber station, remote terminal, wireless terminal, receiving point, vehicle, or user equipment, depending on the type of network. For example, the UE may be a mobile phone, a smart phone, a monitoring device, an alarm device, a fleet management device, an asset tracking device, an automobile, a desktop computer, an entertainment device, an infotainment device, a vending machine, an electricity meter, a water meter, a gas meter, a security device, a sensor device, an appliance, and the like.

The 5G radio supports flexible spectrum utilization from 400MHz to 90GHz for licensed, unlicensed and shared spectrum bands, narrowband and wideband bandwidth allocation with bandwidth portions, carrier aggregation, dual connectivity and dynamic spectrum sharing, achieves higher spectrum occupancy than LTE, and utilizes flexible control channel allocation in the time and frequency domains. Since 3GPP release 15, built-in support for massive MIMO and beamforming greatly enhances the coverage and spectral efficiency achievable when using 5G radios. Flexible Orthogonal Frequency Division Multiplexing (OFDM) parameter sets, short transmission times and scheduling delays, self-contained slots, asynchronous hybrid automatic repeat request acknowledgement (HARQ), minimum overhead of DL common signals and channels, adaptive reference signals and Low Density Parity Check (LDPC), and polar channel coding allow for greater flexibility and faster processing speed for 5G radios compared to LTE.

Furthermore, 5G radios provide optimized support for additional services and features in 3GPP release 16, such as vehicle (V2X) and device-to-device (D2D) communications, wireless backhaul (IAB), coordinated multipoint (COMP) or Multi-TRP transmission and reception (Multi-TRP), cross Link Interference (CLI) and Remote Interference (RIM) detection and avoidance, and NR operation in the unlicensed band (NR-U).

Fig. 1, 2, and 3 below describe various embodiments implemented in a wireless communication system using OFDM or Orthogonal Frequency Division Multiple Access (OFDMA) communication techniques. The descriptions of fig. 1-3 are not meant to imply physical or architectural limitations with respect to the manner in which different embodiments may be implemented. The various embodiments of the present disclosure may be implemented in any suitably arranged communication system.

Fig. 1 illustrates an example wireless network 100 according to an embodiment of this disclosure. The embodiment of the wireless network 100 shown in fig. 1 is for illustration only. Other embodiments of wireless network 100 may be used without departing from the scope of this disclosure.

As shown in fig. 1, wireless network 100 includes base stations BS 101 (such as a gNB), BS 102, and BS 103.BS 101 communicates with BS 102 and BS 103.BS 101 is also in communication with at least one network 130, such as the internet, a private Internet Protocol (IP) network, or other data network.

BS 102 provides wireless broadband access to network 130 for a first plurality of User Equipment (UEs) within coverage area 120 of BS 102. The first plurality of UEs includes UE 111, which may be located in a small enterprise; UE 112, which may be located in enterprise (E); UE 113, which may be located in a WiFi Hotspot (HS); UE 114, which may be located in a first home (R); a UE 115, which may be located in a second home (R); and UE 116, which may be a mobile device (M), such as a cellular telephone, wireless laptop, wireless PDA, etc. BS 103 provides wireless broadband access to network 130 for a second plurality of UEs within coverage area 125 of BS 103. The second plurality of UEs includes UE 115 and UE 116. In some embodiments, one or more of the BSs 101-BS 103 may communicate with each other and with the UE 111-UE 116 using 5G/NR, long Term Evolution (LTE), long term evolution-advanced (LTE-a), wiMAX, wiFi, or other wireless communication technology.

The dashed lines illustrate the general extent of coverage areas 120 and 125, which are shown as approximately circular for purposes of illustration and explanation only. It should be clearly understood that coverage areas associated with BSs, such as coverage areas 120 and 125, may have other shapes, including irregular shapes, depending on the configuration of the BS and the variations in the radio environment associated with natural and man-made obstructions.

As described in more detail below, one or more of UEs 111-116 include circuitry, procedures, or a combination thereof for an effective RA of the UE. In certain embodiments, one or more of the BSs 101-103 comprise circuitry, procedures, or a combination thereof for efficient RA by the UE.

Although fig. 1 illustrates one example of a wireless network, various changes may be made to fig. 1. For example, the wireless network may include any number of BSs and any number of UEs in any suitable arrangement. Further, BS 101 may communicate directly with any number of UEs and provide these UEs with wireless broadband access to network 130. Similarly, each BS 102-BS 103 may communicate directly with network 130 and provide UEs with direct wireless broadband access to network 130. Further, BS 101, BS 102, and/or BS 103 may provide access to other or additional external networks, such as external telephone networks or other types of data networks.

Fig. 2 illustrates an example BS 102 according to an embodiment of the disclosure. The embodiment of BS 102 shown in fig. 2 is for illustration only, and BS 101 and BS 103 of fig. 1 may have the same or similar configurations. However, there are various configurations of BSs, and fig. 2 does not limit the scope of the present disclosure to any particular implementation of a BS.

As shown in fig. 2, BS 102 includes a plurality of antennas 205a-205n, a plurality of Radio Frequency (RF) transceivers 210a-210n, transmit (TX) processing circuitry 215, and Receive (RX) processing circuitry 220.BS 102 also includes a controller/processor 225, memory 230, and a backhaul or network interface 235.

RF transceivers 210a-210n receive incoming RF signals from antennas 205a-205n, such as signals transmitted by UEs in wireless network 100. The RF transceivers 210a-210n down-convert the incoming RF signals to generate IF or baseband signals. The IF or baseband signal is sent to RX processing circuit 220, and RX processing circuit 220 generates a processed baseband signal by filtering, decoding, and/or digitizing the baseband or IF signal. The RX processing circuit 220 sends the processed baseband signals to a controller/processor 225 for further processing.

TX processing circuitry 215 receives analog or digital data (such as voice data, network data, email, or interactive electronic game data) from controller/processor 225. TX processing circuitry 215 encodes, multiplexes, and/or digitizes the outgoing baseband data to generate a processed baseband or IF signal. RF transceivers 210a-210n receive outgoing processed baseband or IF signals from TX processing circuitry 215 and up-convert the baseband or IF signals to RF signals that are transmitted via antennas 205a-205 n.

Controller/processor 225 may include one or more processors or other processing devices that control the overall operation of BS 102. For example, controller/processor 225 may control the reception of uplink channel signals and the transmission of downlink channel signals by RF transceivers 210a-210n, RX processing circuitry 220, and TX processing circuitry 215 in accordance with well-known principles. The controller/processor 225 may also support additional functions, such as higher-level wireless communication functions. For example, the controller/processor 225 may support a directional routing operation in which outgoing signals from the plurality of antennas 205a-205 n/incoming signals to the plurality of antennas 205a-205n are weighted differently to effectively direct the outgoing signals in a desired direction. Controller/processor 225 may support any of a variety of other functions in BS 102. In some embodiments, controller/processor 225 includes at least one microprocessor or microcontroller.

The controller/processor 225 is also capable of executing programs and other processes residing in memory 230, such as an OS. Controller/processor 225 may move data into and out of memory 230 as needed to perform the process.

The controller/processor 225 is also coupled to a backhaul or network interface 235. Backhaul or network interface 235 allows BS 102 to communicate with other devices or systems through a backhaul connection or network. The network interface 235 may support communication via any suitable wired or wireless connection. For example, when BS 102 is implemented as part of a cellular communication system (such as a 5G/NR, LTE, or LTE-a enabled cellular communication system), network interface 235 may allow BS 102 to communicate with other BSs over a wired or wireless backhaul connection. When BS 102 is implemented as an access point, network interface 235 may allow BS 102 to communicate with a larger network, such as the internet, through a wired or wireless local area network, or through a wired or wireless connection. The network interface 235 includes any suitable structure that supports communication over a wired or wireless connection, such as an ethernet or RF transceiver.

Memory 230 is coupled to controller/processor 225. A portion of memory 230 may include RAM and another portion of memory 230 may include flash memory or other ROM.

Although fig. 2 shows one example of BS102, various changes may be made to fig. 2. For example, BS102 may include any number of each of the components shown in fig. 2. As a particular example, an access point may include multiple network interfaces 235 and the controller/processor 225 may support routing functions to route data between different network addresses. As another specific example, BS102 may include multiple instances of each (such as one for each RF transceiver) although shown as including a single instance of TX processing circuitry 215 and a single instance of RX processing circuitry 220. Furthermore, the various components in FIG. 2 may be combined, further subdivided, or omitted, and additional components may be added according to particular needs.

Fig. 3 illustrates an example UE 116 according to an embodiment of this disclosure. The embodiment of UE 116 shown in fig. 3 is for illustration only, and UEs 111-115 of fig. 1 may have the same or similar configuration. However, there are a wide variety of configurations for the UE, and fig. 3 does not limit the scope of the present disclosure to any particular embodiment of the UE.

As shown in fig. 3, UE 116 includes an antenna 305, an RF transceiver 310, TX processing circuitry 315, a microphone 320, and Receive (RX) processing circuitry 325.UE 116 also includes speaker 330, processor (or controller) 340, input/output (I/O) Interface (IF) 345, input device 350, display 355, and memory 360. Memory 360 includes an Operating System (OS) 361 and one or more applications 362.

The RF transceiver 310 receives an incoming RF signal transmitted by a BS of the wireless network 100 from the antenna 305. The RF transceiver 310 down-converts the incoming RF signal to generate an Intermediate Frequency (IF) or baseband signal. The IF or baseband signal is sent to RX processing circuit 325, and RX processing circuit 325 generates a processed baseband signal by filtering, decoding, and/or digitizing the baseband or IF signal. The RX processing circuit 325 sends the processed baseband signal to a speaker 330 (such as for voice data) or to a processor (or controller) 340 for further processing (such as for web-browsing data).

TX processing circuitry 315 receives analog or digital voice data from microphone 320 or other outgoing baseband data (such as network data, email, or interactive video game data) from processor (or controller) 340. TX processing circuitry 315 encodes, multiplexes, and/or digitizes the outgoing baseband data to generate a processed baseband or IF signal. RF transceiver 310 receives the output processed baseband or IF signal from TX processing circuitry 315 and up-converts the baseband or IF signal to an RF signal, which is transmitted via antenna 305.

Processor (or controller) 340 may include one or more processors or other processing devices and execute OS 361 stored in memory 360 to control the overall operation of UE 116. For example, processor (or controller) 340 may control the reception of uplink channel signals and the transmission of downlink channel signals by RF transceiver 310, RX processing circuit 325, and TX processing circuit 315 according to well-known principles. In some embodiments, the processor (or controller) 340 includes at least one microprocessor or microcontroller.

The processor (or controller) 340 is also capable of executing other processes and programs residing in the memory 360, such as processes for beam management. The processor (or controller) 340 may move data into or out of the memory 360 as needed to execute a process. In some embodiments, the processor (or controller) 340 is configured to execute the application 362 based on the OS 361 or in response to a signal received from a BS or operator. The processor (or controller) 340 is also coupled to an I/O interface 345, the I/O interface 345 providing the UE 116 with the ability to connect to other devices, such as laptop computers and handheld computers. I/O interface 345 is the communication path between these accessories and processor (or controller) 340.

The processor (or controller) 340 is also coupled to an input device 350. An operator of UE 116 may input data to UE 116 using input device 350. The input device 350 may be a keyboard, touch screen, mouse, trackball, voice input, or other device capable of functioning as a user interface to allow a user to interact with the UE 116. For example, the input device 350 may include a voice recognition process to allow a user to input voice commands. In another example, the input device 350 may include a touch panel, (digital) pen sensor, key, or ultrasonic input device. The touch panel may recognize a touch input in at least one scheme, such as a capacitive scheme, a pressure sensitive scheme, an infrared scheme, or an ultrasonic scheme, for example.

Processor (or controller) 340 is also coupled to display 355. Display 355 may be a liquid crystal display, a light emitting diode display, or other display capable of presenting text and/or at least limited graphics, such as from a website.

The memory 360 is coupled to the processor (or controller) 340. A portion of memory 360 may include Random Access Memory (RAM) while other portions of memory 360 may include flash memory or other Read Only Memory (ROM).

Although fig. 3 shows one example of the UE 116, various changes may be made to fig. 3. For example, the various components in FIG. 3 may be combined, further subdivided, or omitted, and additional components may be added according to particular needs. As a particular example, the processor (or controller) 340 may be divided into multiple processors, such as one or more Central Processing Units (CPUs) and one or more Graphics Processing Units (GPUs). Furthermore, although fig. 3 shows the UE 116 configured as a mobile phone or smartphone, the UE may be configured to operate as other types of mobile or stationary devices.

A communication system may include a Downlink (DL), which refers to transmission from a base station (such as BS 102) or one or more transmitting points to a UE (such as UE 116), and an Uplink (UL), which refers to transmission from a UE (such as UE 116) to a base station (such as BS 102) or one or more receiving points.

The time unit for DL signaling or UL signaling on a cell is referred to as a slot and may include one or more symbols. The symbol may also be an additional time unit. The frequency (or Bandwidth (BW)) unit is referred to as a Resource Block (RB). One RB includes a plurality of Subcarriers (SCs). For example, one slot may have a duration of 1 millisecond or 0.5 millisecond, including 14 symbols, and an RB may include 12 SCs with an inter-SC interval of 15kHz or 30kHz, and so on.

The DL signals include data signals conveying information content, control signals conveying DL Control Information (DCI), and Reference Signals (RSs), also referred to as pilot signals. The gNB transmits data information or DCI through a corresponding Physical DL Shared Channel (PDSCH) or Physical DL Control Channel (PDCCH). PDSCH or PDCCH may be transmitted on a variable number of slot symbols including one slot symbol. For brevity, a DCI format that schedules PDSCH reception of a UE is referred to as a DL DCI format, and a DCI format that schedules Physical Uplink Shared Channel (PUSCH) transmission from the UE is referred to as an UL DCI format.

The gNB, such as BS 102, transmits one or more of a plurality of types of RSs including channel state information RSs (CSI-RSs) and demodulation RSs (DM-RSs). CSI-RS is primarily intended for UEs to perform measurements and provide Channel State Information (CSI) to the gNB. For channel measurements, non-zero power CSI-RS (NZP CSI-RS) resources are used. For Interference Measurement Reporting (IMR), CSI interference measurement (CSI-IM) resources associated with a zero power CSI-RS (ZP CSI-RS) configuration are used. The CSI processing consists of NZP CSI-RS and CSI-IM resources.

The UE, such as UE 116, may determine CSI-RS transmission parameters through DL control signaling or higher layer signaling, such as Radio Resource Control (RRC) signaling, from the gNB, such as BS 102. The transmission instance of the CSI-RS may be indicated by DL control signaling or configured by higher layer signaling. DM-RS is transmitted only in BW of the corresponding PDCCH or PDSCH, and the UE may demodulate data or control information using DM-RS.

Fig. 4 and 5 illustrate example wireless transmit and receive paths according to this disclosure. In the following description, the transmit path 400 of fig. 4 may be described as being implemented in a BS (such as BS 102), while the receive path 500 of fig. 5 may be described as being implemented in a UE (such as UE 116). However, it is understood that the reception path 500 may be implemented in a BS and the transmission path 400 may be implemented in a UE. In some embodiments, receive path 500 is configured to support RA as described in embodiments of the present disclosure.

The transmit path 400, as shown in fig. 4, includes a channel coding and modulation block 405, a serial-to-parallel (S-to-P) block 410, an Inverse Fast Fourier Transform (IFFT) block 415 of size N, a parallel-to-serial (P-to-S) block 420, an add cyclic prefix block 425, and an Up Converter (UC) 430. The receive path 500 as shown in fig. 5 includes a down-converter (DC) 555, a remove cyclic prefix block 560, a serial-to-parallel (S-to-P) block 565, a Fast Fourier Transform (FFT) block 570 of size N, a parallel-to-serial (P-to-S) block 575, and a channel decoding and demodulation block 580.

As shown in fig. 4, a channel coding and modulation block 405 receives a set of information bits, applies coding, such as Low Density Parity Check (LDPC) coding, and modulates input bits, such as with Quadrature Phase Shift Keying (QPSK) or Quadrature Amplitude Modulation (QAM), to generate a sequence of frequency domain modulation symbols. Serial-to-parallel block 410 converts (such as demultiplexes) the serial modulated symbols into parallel data to generate N parallel symbol streams, where N is the size of the IFFT/FFT used in BS 102 and UE 116. An IFFT block 415 of size N performs an IFFT operation on the N parallel symbol streams to generate a time domain output signal. Parallel-to-serial block 420 converts (such as multiplexes) the parallel time domain output symbols from IFFT block 415 of size N to generate a serial time domain signal. The add cyclic prefix block 425 inserts a cyclic prefix into the time domain signal. Up-converter 430 modulates (such as up-converts) the output of add cyclic prefix block 425 to an RF frequency for transmission via a wireless channel. The signal may also be filtered at baseband before being converted to RF frequency.

The RF signal transmitted from the BS 102 reaches the UE 116 after passing through the wireless channel, and an operation inverse to that at the BS 102 is performed at the UE 116.

As shown in fig. 5, down-converter 555 down-converts the received signal to baseband frequency and remove cyclic prefix block 560 removes the cyclic prefix to generate a serial time domain baseband signal. Serial-to-parallel block 565 converts the time-domain baseband signal into a parallel time-domain signal. The FFT block 570 of size N performs an FFT algorithm to generate N parallel frequency domain signals. Parallel-to-serial block 575 converts the parallel frequency domain signal into a sequence of modulated data symbols. Channel decoding and demodulation block 580 demodulates and decodes the modulated symbols to recover the original input data stream.

Each of BSs 101-BS 103 may implement a transmit path 400 as shown in fig. 4 similar to that transmitted in the downlink to UEs 111-116 and may implement a receive path 500 as shown in fig. 5 similar to that received in the uplink from UEs 111-116. Similarly, each of UEs 111-116 may implement a transmit path 400 for transmitting in the uplink to BS 101-BS 103 and may implement a receive path 500 for receiving in the downlink from BS 101-BS 103.

Each of the components in fig. 4 and 5 may be implemented using hardware or using a combination of hardware and software/firmware. As a specific example, at least some of the components in fig. 4 and 5 may be implemented in software, while other components may be implemented by configurable hardware or a mixture of software and configurable hardware. For example, FFT block 570 and IFFT block 515 may be implemented as configurable software algorithms, wherein the value of size N may be modified according to the implementation.

Further, although described as using an FFT and an IFFT, this is only exemplary and should not be construed as limiting the scope of the present disclosure. Other types of transforms may be used, such as Discrete Fourier Transform (DFT) and Inverse Discrete Fourier Transform (IDFT) functions. It will be appreciated that for DFT and IDFT functions, the value of the variable N may be any integer (such as 1, 2, 3, 4, etc.), while for FFT and IFFT functions, the value of the variable N may be any integer that is a power of 2 (such as 1, 2, 4, 8, 16, etc.).

Although fig. 4 and 5 show examples of wireless transmission and reception paths, various changes may be made to fig. 4 and 5. For example, the various components in fig. 4 and 5 may be combined, further subdivided, or omitted, and additional components may be added according to particular needs. Further, fig. 4 and 5 are intended to illustrate examples of the types of transmit and receive paths that may be used in a wireless network. Any other suitable architecture may be used to support wireless communications in a wireless network.

In some embodiments, the UL signals further include a data signal conveying information content, a control signal conveying UL Control Information (UCI), DM-RS associated with data or UCI demodulation, sounding RS (SRS) enabling the gNB to perform UL channel measurements, and RA preamble enabling the UE to perform RA (see also NR specifications). The UE transmits data information or UCI through a corresponding PUSCH or Physical UL Control Channel (PUCCH). PUSCH or PUCCH may be transmitted on a variable number of slot symbols including one slot symbol. The gNB may configure the UE to transmit signals on the cell within an active UL bandwidth portion (BWP) of the cell UL BW.

UCI includes HARQ Acknowledgement (ACK) information indicating correct or incorrect detection of a data Transport Block (TB) in PDSCH, a Scheduling Request (SR) indicating whether the UE has data in a buffer, and CSI reports enabling the gNB to select appropriate parameters for PDSCH or PDCCH transmission to the UE. The HARQ-ACK information may be configured to have a smaller granularity than per TB, and may be per data Code Block (CB) or per group of data CBs, where a data TB includes a plurality of data CBs.

The CSI report from the UE may include a Channel Quality Indicator (CQI) informing the gNB of a maximum Modulation and Coding Scheme (MCS) for the UE to detect a data TB having a predetermined block error rate (BLER), such as 10% BLER (see NR specifications), a Precoding Matrix Indicator (PMI) informing the gNB of how to combine signals from multiple transmitter antennas according to the MIMO transmission principle, and a rank indicator indicating a transmission rank of the PDSCH.

UL RS includes DM-RS and SRS. DM-RS is sent only in BW of the corresponding PUSCH or PUCCH transmission. The gNB may demodulate information in the corresponding PUSCH or PUCCH using DM-RS. SRS is sent by the UE to provide UL CSI to the gNB, and for TDD systems, SRS transmissions may also provide PMIs for DL transmissions. In addition, to establish a synchronization or initial higher layer connection with the gNB, the UE may transmit a physical random access channel (PRACH as shown in the NR specifications).

An antenna port is defined such that a channel on which a symbol on the antenna port is transmitted can be inferred from channels on which other symbols on the same antenna port are transmitted.

For DM-RS associated with PDSCH, the channel on which the PDSCH symbol on one antenna port is transmitted may be inferred from the channel on which the DM-RS symbol on the same antenna port is transmitted only if both symbols are within the same resource, in the same time slot, and in the same precoding resource block group (PRG) as the scheduled PDSCH.

For DM-RS associated with PDCCH, the channel on which the PDCCH symbol on one antenna port is transmitted can be inferred from the channel on which the DM-RS symbol on the same antenna port is transmitted only if both symbols are within resources that the UE can assume to use the same precoding.

For DM-RS associated with a Physical Broadcast Channel (PBCH), the channel on which the PBCH symbol on one antenna port is transmitted can be inferred from the channel on which the DM-RS symbol on the same antenna port is transmitted, only if both symbols are transmitted in the same slot and have the same block index SS/PBCH block.

Two antenna ports are said to be quasi co-located if the massive nature of the channel over which the symbols on one antenna port are transmitted can be inferred from the channel over which the symbols on the other antenna ports are transmitted. The large scale properties include one or more of delay spread, doppler shift, average gain, average delay, and spatial Rx parameters.

A UE, such as UE 116, may assume that Synchronization Signals (SS)/PBCH blocks (also denoted SSB) transmitted with the same block index at the same center frequency location are quasi co-sited with respect to doppler spread, doppler shift, average gain, average delay, delay spread, and (when applicable) spatial Rx parameters. The UE may not assume quasi co-location for any other synchronization signal SS/PBCH block transmission.

Without CSI-RS configuration, and unless otherwise configured, the UE may assume PDSCH DM-RS and SSB to be quasi co-sited with respect to doppler shift, doppler spread, average delay, delay spread, and (when applicable) spatial Rx parameters. The UE may assume PDSCH DM-RS within the same Code Division Multiplexing (CDM) group to be quasi co-sited with respect to doppler shift, doppler spread, average delay, delay spread, and spatial Rx. The UE may also assume DM-RS ports associated with PDSCH with QCL type a, type D (when applicable) and average gain QCL. The UE may further assume that no DM-RS collides with SS/PBCH blocks.

The UE may be configured with a list of up to M Transmission Configuration Indication (TCI) status configurations within the higher layer parameters PDSCH-Config (PDSCH-configuration) to decode PDSCH from detected PDCCH with DCI intended for the UE and a given serving cell, where M depends on UE capability maxnumberconfigureguidtstatterpercc. Each TCI state contains parameters for configuring a quasi co-sited (QCL) relationship between one or two downlink reference signals and a DM-RS port of a PDSCH, a DM-RS port of a PDCCH, or a CSI-RS port of a CSI-RS resource.

The quasi co-sited relationship is configured by the higher layer parameters qcl-Type1 for the first DL RS and qcl-Type2 for the second DL RS (if configured). For the case of two DL RSs, the QCL type may be different whether the reference is for the same DL RS or different DL RSs. The quasi co-location Type corresponding to each DL RS is given by a higher layer parameter QCL-Type (QCL-Type) in QCL-Info (QCL-Info), and may take one of the following values: QCL-TypeA: { Doppler shift, doppler spread, average delay, delay spread }; QCL-TypeB: { Doppler shift, doppler spread }; QCL-TypeC: { Doppler shift, average delay }; and QCL-TypeD: { spatial Rx parameters }.

The UE receives the MAC-CE activation command to get up to N](e.g., n=8) TCI states map to the code point of the DCI field "transmission configuration indication". When transmitting the HARQ-ACK corresponding to the PDSCH carrying the activation command in slot n, the MAC-CE application time may be followed, e.g., from the slotThe first time slot thereafter starts, an indication mapping between the TCI state and the code point of the DCI field "transmission configuration indication" is applied.

In some embodiments, the RA procedure is initiated by: RRC (for SI request) -if SIB1 includes scheduling information for (on-demand) SI request; a MAC; and a PDCCH order (PDCCH-order).

The RA procedure may be initiated due to at least one of the following triggers/objectives: (i) Initial access to establish RRC connection (from rrc_idle or rrc_inactive to rrc_connected); (ii) Reestablishing the RRC connection after a Radio Link Failure (RLF); (iii) an on-demand System Information (SI) request; (iv) switching; (v) UL synchronization; (vi) a Scheduling Request (SR); (vii) positioning; and (viii) link recovery (also known as Beam Fault Recovery (BFR)).

Note that RA can operate in two modes: (i) Contention-based random access (CBRA), in which UEs within a serving cell can share the same RA resources, and therefore there is a possibility of collision among RA attempts from different UEs, and (ii) contention-free random access (CFRA), in which UEs have dedicated RA resources indicated by the serving gNB and cannot be shared with other UEs, so that RA collisions can be avoided. For example, CBRA may be used for all triggers/purposes described above, while CFRA may be used only for triggers/purposes (iv) to (viii) as shown above.

The 4-step RA procedure, also called type-1 (L1) RA procedure, consists of the following steps/operations of the UE: transmission of PRACH preamble (Msg 1); attempting to receive an RA response (RAR or Msg 2); transmitting a contention resolution message (Msg 3); and attempting to receive a contention resolution message (Msg 4).

Alternative RA procedures are also considered, which are so-called 2-step RACH or type-2 l1 RA procedures, where Msg1 and Msg3 are combined into an "MsgA" transmission, and above Msg2 and Msg4 are combined into an "MsgB" reception.

Various embodiments of the present disclosure relate to a 4-step RACH, although these embodiments are generally applicable to a 2-step RACH as well, and for brevity, explicit separate descriptions are generally omitted.

PRACH preamble transmission (for both CBRA and CFRA modes) is associated with DL RS. The association may help the serving gNB (such as BS 102) identify an uplink spatial receive filter/beam to receive the PRACH and may also help the UE identify an uplink spatial transmit filter/beam to transmit the PRACH. For example, the UE may use the uplink transmission filter/beam for DL reception of the indicated DL RS of the Msg1 transmission to be the same or related (such as having the same QCL properties and/or the same direction but a narrower width) uplink transmission filter/beam. The association may also be used to provide DL RS resources for path loss estimation to determine PRACH preamble transmission power in the NR specifications.

Based on PRACH scenario, DL RS for Msg1 transmission may be one of the following options: SSB: for BFR, CFRA, PDCCH command PRACH, SI request, CBRA; or CSI-RS: for BFR, CFRA, CBRA.

Note that throughout this disclosure SSB is used as a short form of SS/PBCH block. The terms SSB and SS/PBCH block are used interchangeably in this disclosure.

Further, the serving cell can be configured with both SSBs and CSI-RSs for PRACH transmission. For example, some PRACH preambles may be associated with SSBs for 7QCL determination, while some PRACH preambles may be associated with CSI-RS for QCL determination. It is also possible that the secondary serving cell (SCell) does not have any SSB configuration/transmission and only supports PRACH transmission from UEs using CSI-RS for QCL determination. Then, as described in the previous paragraph, certain RA triggers/modes, such as PDCCH order or SI request for RA, are not applicable.

The RACH configuration includes RACH slots and RACH Opportunities (ROs) in certain frequency resource blocks that repeat in certain periods.

NR uses a Zadoff-Chu sequence for the PRACH preamble. There are 3 PRACH long preamble formats with a sequence length of 839 and a subcarrier spacing of 1.25 or 5kHz. The long sequence supports an unlimited set and a limited set of types a and B. For beam scanning purposes within RACH opportunities, NR uses a new set of PRACH preamble formats of short sequence length 139 on sub-carrier intervals (SCS) of 1, 2, 4, 6 and 12 OFDM symbols and 15, 30, 60 and 120 kHz. These consist of a single or consecutively repeated RACH sequence. A cyclic prefix is inserted at the beginning of the preamble. A Guard Time (GT) may be appended at the end of the preamble while a Cyclic Prefix (CP) and a gap between RACH sequences are omitted. Short sequences only support unlimited sets. For both short and long PRACH preamble sequences, the network may also perform beam scanning reception between RACH opportunities.

A plurality of RACH preamble formats are defined for one or more PRACH symbols. Possibly, different CP and GT lengths may be used. The PRACH preamble configuration is signaled to the UE through RRC. The RRC informs the UE of the association between the SSB and RACH resources. The threshold for SSB for RACH resource association is based on reference signal received power (Reference Signal Received Power, RSRP) and is configurable by the network. The UE, such as UE 116, may calculate the PRACH transmit power for preamble retransmission based on a recent estimate of the pathloss and a power increase (power pumping) counter. If the UE performs beam switching, the counter of power increase does not change.

The physical layer of the UE receives the set of SSB indexes and provides RSRP measurements for the indexed SSB candidates to the UE RRC sub-layer prior to RACH preamble transmissionAnd (5) collecting. The information required by the UE physical layer prior to PRACH preamble transmission includes preamble format, time resource and frequency resource for PRACH transmission, and parameters for determining root sequences and cyclic shifts thereof in the PRACH preamble sequence set, including index of logical root sequence table, cyclic shift N _CS And set types, i.e., unlimited, limited set a or limited set B.

The SSB index maps to the PRACH opportunity in an ascending order of the preamble index within a single PRACH opportunity, then in an ascending order of the frequency resource index of the frequency multiplexed PRACH opportunity, then in an ascending order of the time resource index of the time multiplexed PRACH opportunity within the PRACH slot, and finally in an ascending order of the index of the PRACH slot. The association period for mapping SSBs to PRACH opportunities starting from frame 0 is the minimum of the set determined by the PRACH configuration period, such that N _SSB The individual SS/PBCH blocks are mapped to PRACH opportunities at least once within the association period. UE obtains parameter N from RRC _SSB . If there is no mapping to N after an integer number of SSB to PRACH opportunity mapping cycles within the association period _SSB A set of PRACH opportunities for SSBs, no SSB is mapped to the set of PRACH opportunities. The association pattern period includes one or more association periods and is calculated such that the pattern between the PRACH opportunity and the SSB is repeated at most once every 160 milliseconds. PRACH opportunities (if any) that are not associated with SSBs after an integer number of association periods are not used for PRACH transmission.

PRACH preamble transmission may occur within a configurable subset of time slots, referred to as PRACH slots, and be repeated every PRACH configuration period. In the coverage of NRB ^{PRACH-Preamble} N _PRACH There may be multiple PRACH opportunities within each PRACH slot in the frequency domain of the multiple consecutive RBs, where NRB ^{PRACH-Preamble} Is the preamble bandwidth measured in number of RBs, and N _PRACH Is the number of frequency domain PRACH opportunities.

The next available PRACH opportunity in the PRACH opportunities corresponding to the selected SSB may be further limited by the parameter ra-SSB-occidionmassindex (ra-SSB-opportunity mask index) if configured or indicated by the PDCCH. Otherwise, the UE MAC randomly selects PRACH opportunities with equal probability among consecutive PRACH opportunities. Measurement gaps are also considered in determining the next available PRACH opportunity corresponding to the selected SSB. Similarly, the parameter ra-OccasionList (ra-opportunity list) may limit the PRACH opportunity when associated with the CSI-RS, where the PRACH preamble may be transmitted.

Fig. 6 illustrates an example diagram 600 of PRACH time and frequency domain allocations and parameter configurations in accordance with an embodiment of the disclosure. The diagram 600 is for illustration only, and other embodiments may be used without departing from the scope of the present disclosure.

For a given preamble type, corresponding to a certain preamble bandwidth, the overall available time-frequency PRACH resources within a cell may be described by the following parameters: a configurable PRACH period that may range from 10 to 160 milliseconds; a set of configurable PRACH slots within a PRACH period; and a configurable frequency domain PRACH resource given by an index of a first RB in the resource and a number of frequency domain PRACH opportunities.

In some embodiments, a UE, such as UE 116, may send the PRACH preamble only in time resources signaled via the RRC parameter PRACH-configuration index (PRACH-configuration index), and also depends on the frequency range (FR 1 or FR 2) and the spectrum type. The UE may transmit the PRACH preamble only in the frequency resource indicated by the parameter msg1-FrequencyStart (msg 1-frequency start). PRACH frequency resource nra= {0;1, a step of; ..; m-1, where parameter M is derived from RRC parameter msg1-FDM, numbered in ascending order starting from the lowest frequency within the initial active UL bandwidth portion during initial access.

The UE determines the transmission power for PRACH on the active UL BWP b of carrier f of serving cell c based on DL RS for serving cell c in transmission opportunity i, P _PRACH,b,f,c (i) As described in the following equation (1).

[ equation 1]

P _PRACH,b,f,c (i)＝min{P _CMAX,f,c (i),P _{PRACH,target,f,c} +PL _b,f,c }[dBm] (1)

As described in equation (1), P _CMAX,f,c (i) Is the maximum output power the UE is configured for carrier f of serving cell c within transmission opportunity i.In addition, P _{PRACH,target,f,c} Is the PRACH TARGET RECEIVED POWER preamble_received_target_power provided by the upper layer for the active UL BWP b of carrier f of serving cell c ((preamble_received_target_power)). Furthermore, PL _b,f,c Is based on the path loss of the active UL BWP b of carrier f of DL RS associated with PRACH transmission on the active DL BWP of serving cell c and is calculated by UE in dB as (reference signal power) -higher layer filter RSRP in dBm and the higher layer filter configuration is defined in RRC.

If the PRACH transmission from the UE is not in response to the detection of the PDCCH order by the UE, or in response to the detection of the PDCCH order by the UE triggering a contention-based RA procedure, or is associated with a link recovery procedure, wherein the corresponding index q _new Associated with SSB, the reference signal power is provided by ss-PBCH-BlockPower.

If the PRACH transmission from the UE is responsive to detection of a PDCCH order of the UE triggering the contention-free RA procedure and the DL RS with which the DM-RS depending on the PDCCH order is quasi-co-located, the reference signaling power is provided by the ss-PBCH-BlockPower, or if the UE is configured for resources for periodic CSI-RS reception, or the PRACH transmission is associated with a link recovery procedure, wherein the corresponding index q _new In association with the periodic CSI-RS configuration, the prefercesignalpower is obtained through ss-PBCH-BlockPower and powerControlOffsetSS, which provide an offset of CSI-RS transmission power with respect to SSB transmission power. If powercontrol offsetss is not provided to the UE, the UE assumes an offset of 0dB.

After RACH preamble transmission, if the UE does not receive an RA response containing an RA preamble identifier (RAPID) corresponding to a preamble sequence transmitted by the UE within an RRC signaled RA response window and a configurable size RA-response window, the UE typically increases the transmission power (step-wise) to a certain limit, such as a limit defined by the maximum transmission power, using a power increase counter for subsequent PRACH transmissions. If the UE changes the spatial domain transmission filter before PRACH retransmission, the UE physical layer informs the higher layer to suspend the power up counter.

For each PRACH PREAMBLE retransmission attempt, the UE increases preamble_transmission_counter by 1 and applies an adjustment value delta_preamble to determine the TRANSMISSION power for the subsequent PRACH TRANSMISSION as described in equation (2) below.

[ equation 2]

Preamble_received_target_power=preamble RECEIVED TARGET power+delta_preamble + (preamble_power_increment_counter) -1) ×preamble_power_ramp_step (2)

For the 4-STEP RACH procedure, the expression preamble_power_ramp_step is set to the higher layer parameter powerramp STEP. For the case of the 2-STEP RACH procedure, the preamble_power_ramp_step may be set separately using the higher layer signaled parameter msgA-preablefaceramp_step (msgA-PREAMBLE POWER increase STEP), and the ra-prioritisation (ra-Prioritization) may be configured separately using the signaled parameter powerramp STEP high priority.

The value of the adjustment step delta_preamble depends on the PREAMBLE format and SCS, as shown in table (1) and table (2). Here, μ is SCS configuration determined by msg 1-subsearrierspace (4-step RACH) or msgA-subsearrierspace (2-step RACH), and the preamble format is given by PRACH-configuration index or msgA-PRACH-configuration index. Tables (1) and (2) describe DELTA _ PREAMBLE values for the short PREAMBLE format.

[ Table 1 ]

Preamble format	DELTA_PREABLE value
		0	0dB
1	-3dB
		2	-6dB
3	0dB

[ Table 2 ]

Preamble format	DELTA_PREABLE value (dB)
		A1	8+3×μ
A2	5+3×μ
		A3	3+3×μ
B1	8+3×μ
		B2	5+3×μ
B3	3+3×μ
		B4	3×μ
C0	11+3×μ
		C2	5+3×μ

After the UE transmits the PRACH preamble (Msg 1), there are three steps for the UE's (4 steps) RA procedure: receiving an RA response (RAR or Msg 2) from the gNB; transmitting a contention resolution message (Msg 3) to the gNB; and receiving a contention resolution response message (Msg 4) from the gNB.

The RA response (RAR or Msg 2) is PDCCH/PDSCH reception on the DL BWP of the PCell/SpCell, which is either an initial DL BWP (for the case of initial access, i.e. the RRC connection is (re) established) or an active DL BWP (with the same BWP index as the active UL BWP) (for other RA triggers than initial access), as described below. If the active DL BWP index is different from the active UL BWP index, the UE changes the active DL BWP to DL BWP having the same BWP index as the active UL BWP.

The SCS used for PDCCH reception scheduling PDSCH with RAR message is the SCS of the type 1-PDCCH Common Search Space (CSS) set as described in REF 3. The SCS for any subsequent PDCCH/PDSCH reception is also the same as the SCS for PDCCH/PDSCH providing the RAR, unless the UE is configured with a different SCS.

The UE, such as UE 116, monitors the PDCCH during a configured time window to detect DCI format 1_0 scheduling PDSCH providing RAR in a search space indicated by the recovery search space Id in the PCell/SpCell identified by the cell-radio temporary identifier (C-RNTI) according to the type 1-PDCCH CSS set of PCell/SpCell identified by the RA-radio network temporary identifier (RA-RNTI) (or, for the case of Beam Failure Recovery (BFR) with CFRA).

The RAR includes information for one or more UEs, some of which are common to the UEs, while the remaining information is UE-specific.

In one example, the RAR includes a 4-bit back-off indicator (Backoff Indicator, BI) that indicates a maximum back-off time required before the UE makes the next PRACH transmission attempt. The UE randomly and uniformly selects an actual backoff time between zero and the value indicated by the BI field. BI is typically used to control the load of PRACH preamble transmission on the serving cell.

In another example, the RAR includes a RAPID, such as through a 6-bit field, that indicates the ID of the preamble transmitted by the UE and is a response to a System Information (SI) request of the UE.

In another example, the gNB sends the RAPID along with a MAC payload (MAC RAR) that includes a Timing Advance (TA) command, an uplink grant (grant) for scheduling the Msg3 PUSCH, and a temporary C-RNTI (TC-RNTI).

FIG. 7 illustrates an example diagram 700 of an E/T/R/R/BI MAC sub-header 600 in accordance with an embodiment of the disclosure. Fig. 8 illustrates an example diagram 800 of an example E/T/RAPID MAC subheader 650 in accordance with an embodiment of the disclosure. Fig. 9 shows an example diagram 900 of a MAC RAR 670 according to an embodiment of the present disclosure. The diagrams 700 of fig. 7, 800 of fig. 8, and 900 of fig. 9 are for illustration only, and other embodiments may be used without departing from the scope of the present disclosure.

One or more of the components shown in fig. 7, 8, and 9 may be implemented in dedicated circuitry configured to perform the functions described, or one or more components may be implemented by one or more processors that execute instructions to perform the functions described. Other embodiments may be used without departing from the scope of this disclosure.

Table (3) includes an exemplary RA response grant content field and a corresponding size. In particular, table (3) describes the MAC RAR grant field size.

[ Table 3 ]

RAR grant field	Number of bits
		Frequency hopping mark	1
PUSCH frequency resource allocation	14
		PUSCH time resource allocation	4
MCS	4
		TPC commands for PUSCH	3
CSI request	1
		Total number of bits	27

For CFRA-based BFRs, when a UE receives PDSCH scheduled by a DCI format, such as UE 116, with a Cyclic Redundancy Check (CRC) scrambled by the C-RNTI for the UE, provided by PDCCH reception according to the indicated set of search spaces, the UE considers the RAR reception to be successful.

For other cases (such as CBRA and SI requests), RAR is successful for the UE when the UE is in the following case: (i) During a configured time window, receiving a PDCCH according to a type 1-PDCCH CSS set of SpCell, which provides a DCI format addressed to RA-RNTI; and (ii) correctly decoding a transport block in a PDSCH scheduled by the DCI format; and (iii) obtaining the same RAPID as the RAPID of the PRACH preamble transmitted in Msg1 from the MAC RAR in the PDSCH. Then, for a serving cell in which the UE transmits a PRACH preamble (Msg 1), the UE applies TA to adjust timing between transmission and reception, stores TC-RNTI provided by the MAC RAR for future transmission/reception, and processes RAR UL grant to transmit Msg3 PUSCH.

If the UE's RAR reception is unsuccessful, the UE attempts (possibly at backoff and/or UE processing time up to N _T,1 After +0.75 ms, as described in REF 3) a new PRACH preamble transmission with PRACH resource selection (possibly including a different SSB and/or a different preamble) and possibly by applying PRACH preamble power increase unless the UE has reached the maximum number of configurations of PRACH attempts, then the UE reports RA problems to higher layers and stops the RA procedure.

The resource allocation for the Msg3 PUSCH (as indicated by the RAR UL grant) includes the following fields from table 1: a frequency hopping flag; PUSCH time resource allocation; and PUSCH frequency resource allocation.

The time resource allocation field indicates the starting symbol and the time domain length of the Msg3 PUSCH transmission.

The frequency domain resource allocation field is used for uplink resource allocation type 1 and indicates the allocation of consecutive (virtual) resource blocks, as described in REF 3.

It is noted that as used herein, the terms "4-step RA", "type-1 RA procedure" and "type-1 L1 RA procedure" are used interchangeably. Furthermore, the terms "2-step RA", "type-2 RA procedure" and "type-2 L1 RA procedure" may be used interchangeably.

Before the UE initiates the physical RA procedure, layer 1 of the UE receives an indication from a higher layer to perform a type-1 RA procedure (4-step RA) or a type-2 RA procedure (2-step RA).

From the physical layer perspective, the type-2 L1 RA procedure includes transmission of RA preambles (MsgA) in PRACH and PUSCH, and reception of RAR messages (MsgB) with PDCCH/PDSCH. When the RAR for the 2-step RA procedure indicates to fall back to the 4-step RA (i.e., fallback RAR), the 2-step RA procedure continues, i.e., PUSCH transmission scheduled by the RAR UL grant and PDSCH reception for contention resolution, similarly to the 4-step RA procedure.

The PRACH preamble for 2-step RA is independent of the PRACH preamble for 4-step RA, e.g., the contention-based preamble for each SS/PBCH block of each valid PRACH opportunity for 2-step RA procedure starts after the preamble for 4-step RA procedure.

In some embodiments, the RO for the 2-step RA procedure and the RO for the 4-step RA procedure may be public/shared or independent of the RO for the 4-step RA procedure.

In response to the PRACH and PUSCH transmissions, the UE attempts to detect DCI format 1_0 with CRC scrambled by the corresponding RA-RNTI/MsgB-RNTI during windows controlled by the higher layers, e.g., as described in REF3 and REF 4. The window starts at a first symbol of an earliest CORESET that the UE is configured to receive PDCCHs according to the type 1-PDCCH CSS set, e.g., as described in REF3, which is at least one symbol after a last symbol of a PUSCH opportunity corresponding to a PUSCH transmission (associated with a 2-step RA procedure), where the symbol duration corresponds to the SCS for the type 1-PDCCH CSS set. The SCS based on the type 1-PDCCH CSS set, the window length in units of the number of slots is provided by RA-ResponseWindow (for 4-step RA procedure), or a separate configuration may be provided for the time window length of 2-step RA procedure.

If the UE detects a transport block in DCI format 1_0 with CRC scrambled by the corresponding RA-RNTI/MsgB-RNTI and PDSCH corresponding thereto within the window, the UE delivers the transport block to higher layers.

The higher layer indicates to the physical layer one of: (a) The UE procedure continues as in the 4-step RA procedure when the UE detects an RAR UL grant when the RAR message is for a fallback RAR and the RAPID associated with the PRACH transmission is identified, or (b) an ACK is provided in the PUCCH transmission when the RAR message is for a success RAR. When the UE transmits the PUCCH providing the ACK, the PUCCH resource for PUCCH transmission is indicated by a 4-bit PUCCH Resource Indicator (PRI) field in the success rar of the PUCCH resource set provided by PUCCH-resource com mon; the slot for PUCCH transmission is defined by a 3-to-3 ratio in the success rar with a value k from {1,2,3,4,5,6,7,8}Specific PDSCH-to-HARQ feedback timing indicator field indication and reference has duration T _slot Is determined as ceil (n+k+delta+t) _Δ /T _slot ) Where n is the slot of PDSCH reception, delta is defined, for example, as in REF3 for PUSCH transmission or according to a different table provided in the system specification, and t _Δ And is more than or equal to 0. The first symbol of the UE not expecting PUCCH transmission is less than N after the last symbol received by PDSCH _T,1 +0.5+t _Δ Time of millisecond, where N _T,1 Is the PDSCH processing time for UE processing capability 1 as described in REF 4. The PUCCH transmission has the same spatial domain transmission filter as the last PUSCH transmission and is in the same active UL BWP.

If the UE detects DCI format 1_0 and a transport block with CRC scrambled by C-RNTI in a corresponding PDSCH within a window, the UE transmits PUCCH of HARQ-ACK information with an ACK value when the UE correctly detects the transport block or transmits PUCCH with a Negative Acknowledgement (NACK) value when the UE does not correctly detect the transport block, and a time alignment timer is running.

The UE does not expect to be instructed to transmit the PUCCH with HARQ-ACK information at a time before the time at which the UE applies the TA command provided by the transport block.

If the UE does not detect DCI format 1_0 with CRC scrambled by the corresponding RA-RNTI/MsgB-RNTI within the window, or if the UE does not correctly receive a transport block in the corresponding PDSCH within the window, or if the higher layer does not identify a RAPID associated with PRACH transmission from the UE, the higher layer may instruct the physical layer to perform a type-1 RA procedure or to perform a type-2 RA procedure.

If higher layer requests, the UE is expected to N after the last symbol of the window or the last symbol received by PDSCH _T,1 +0.75 ms to transmit PRACH, where N _T,1 Is N ₁ The duration of a symbol corresponds to the PDSCH processing time of UE processing capability 1 when the additional PDSCH DM-RS is configured. For μ=0, ue assumes N _1,0 =14 as described in REF3 and REF 4.

For Contention Free RA (CFRA) and SI requests, the correct reception of Msg2/RAR is the last step in the RA procedure. However, for contention-based RA (CBRA), it is possible that multiple UEs may have used the same preamble and further steps are required to resolve the contention. Furthermore, for RA prior to rrc_connected state, such as for initial access, UE and gNB need to exchange further information to establish a connection, msg3 PUSCH transmission is required for contention resolution request and possible connection establishment request, and Msg4PDSCH transmission is required for contention resolution response and possible connection establishment response. If the UE receives the Msg4PDSCH within a certain time window after transmitting Msg3, and when the UE does not receive the C-RNTI, the contention resolution (and connection establishment, if applicable) is considered successful also if the contention resolution ID in the Msg4PDSCH matches the ID the UE transmitted in the Msg3 PUSCH. Otherwise, the contention resolution Msg3/4 and thus RA attempts are unsuccessful. The UE may make another RA attempt unless the configured maximum number of RA attempts has been reached, and then the entire RA procedure is declared unsuccessful.

Upon failure of the RA attempt (due to no RAR reception, no match of RAPID in RAR with RAPID in Msg1, or contention resolution Msg3/4 failure), the UE may perform a new RACH resource selection for the new RA attempt, including selecting DL RS associated with PRACH transmission, selecting PRACH preamble, and selecting RO. Thus, it is possible that a different SSB/CSI-RS and/or a different PRACH preamble and/or a different RO may be used for PRACH transmission of a new RA attempt than a previous RA attempt. However, power increase is only applied when the same DL RS is used in PRACH transmission for both new RA attempts and previous RA attempts.

In the following and throughout the disclosure, various embodiments of the present disclosure may also be implemented in any type of UE, including, for example, UEs with the same, similar, or more capabilities than a conventional 5G NR UE. Although various embodiments of the present disclosure discuss a 3GPP 5g NR communication system, these embodiments may generally be applied to UEs operating using other RATs and/or standards (such as the next release/generation of 3GPP, IEEE WiFi, etc.).

In the following, unless explicitly indicated otherwise, providing parameter values by higher layers includes providing parameter values through a System Information Block (SIB), such as SIB1, or through common RRC signaling, or through UE-specific RRC signaling.

Hereinafter, the association between DL RSs, such as SS/PBCH blocks (SSBs) or CSI-RSs, and PRACH preambles is determined with respect to path loss for calculating the power of PRACH preamble transmission, and with respect to QCL attributes or Transmission Configuration Indicator (TCI) status, as described in REF 3.

In certain embodiments, the 5G NR radio supports Time Division Duplex (TDD) operation and Frequency Division Duplex (FDD) operation. The use of FDD or TDD depends on the NR frequency band and the allocation of each country. TDD is required in most frequency bands above 2.5 GHz.

Fig. 10 illustrates an example diagram 1000 of a structure of a slot of a TDD communication system according to an embodiment of the present disclosure. The diagram 1000 is for illustration only, and other embodiments may be used without departing from the scope of the present disclosure.

The DDDSU UL-DL configuration is shown in fig. 10. Here, D denotes a DL slot, U denotes a UL slot, S denotes a special or switching slot with a DL portion, which may also be used as a flexible portion of the guard period G for DL-to-UL switching, optionally a UL portion.

TDD has further advantages over FDD. For example, the same frequency band for DL and UL transmissions results in a simpler UE implementation than TDD, as a duplexer is not required. Another advantage is that time resources can be flexibly allocated to UL and DL in consideration of asymmetric ratio of traffic in two directions. In TDD, DL is typically allocated most of the time resources to handle DL heavy mobile traffic. Another advantage is that CSI can be more easily acquired via channel reciprocity. This reduces the overhead associated with CSI reporting, especially when there are a large number of antennas.

Although TDD has advantages over FDD, there are drawbacks as well. The first disadvantage is that TDD coverage is smaller because typically a small fraction of the time resources are available for UL transmission, while for FDD all time resources are available for UL transmission. Another disadvantage is the time delay. In TDD, the timing gap between DL reception and UL transmission containing hybrid automatic repeat request acknowledgement (HARQ-ACK) information associated with DL reception is typically beaten, e.g., a few milliseconds, than in FDD. Thus, the HARQ round trip time in TDD is typically longer than in FDD, especially when DL traffic load is high. This results in increased UL user plane delay in TDD and may lead to data throughput loss or even HARQ stalling (bundling) when the PUCCH providing HARQ-ACK information needs to be repeatedly transmitted in order to improve coverage (an alternative in this case is that the network discards the HARQ-ACK information at least for some transport blocks in DL).

To address some of the drawbacks of TDD operation, dynamic adaptation of link direction has been considered, where the symbols of a slot may have a flexible direction (UL or DL) that the UE may determine from scheduling information for transmission or reception, in addition to some symbols in some slots supporting a predetermined transmission such as SSB. The PDCCH may also be used to provide a DCI format, such as DCI format 2_0 as described in REF3, which may indicate the link direction of some flexible symbols in one or more slots. However, in practical deployments, it is difficult for the gNB scheduler to adapt the transmission direction of the symbols without coordination with other gNB schedulers in the network. This is due to CLI, where, for example, DL reception by a UE in a cell may experience large interference from UL transmissions from other UEs in the same or neighboring cells.

FD communication offers the potential to increase spectral efficiency, improve capacity, and reduce latency in wireless networks. When FD communication is used, UL and DL signals are received and transmitted simultaneously on fully or partially overlapping or adjacent frequency resources, thereby improving spectral efficiency and reducing latency in the user and/or control plane.

There are several options for operating FD wireless communication systems. For example, a single carrier may be used such that transmissions and receptions are scheduled on the same time domain resource (such as a symbol or slot). The transmission and reception on the same symbol or slot may be separated in frequency, for example by placement in non-overlapping subbands. In the time domain resources that also include DL frequency subbands, the UL frequency subbands may be located at the center of the carrier, or at edges of the carrier, or at selected frequency domain locations of the carrier. The allocations of DL subbands and UL subbands may also overlap partially or even completely. The gNB may use the same physical antennas, antenna ports, antenna panels, and transmitter-receiver units (TRX) to transmit and receive simultaneously in time domain resources. The transmission and reception in the FD may also occur using separate physical antennas, ports, panels or TRXs. The antennas, ports, panels, or TRXs may also be partially reused, or only a corresponding subset may be active for transmission and reception when FD communication is enabled.

Instead of using a single carrier, different component carriers (Component Carrier, CC) may also be used for reception and transmission by the UE. For example, reception by the UE may occur on a first CC, while transmission by the UE occurs on a second CC that has a small (including zero) frequency separation from the first CC.

Further, even when the UE is still operating in half duplex mode, such as when the UE can transmit and receive simultaneously, the gNB can operate in FD mode or the UE can also perform FD operation.

FD transmission/reception is not limited to the gNB, TRP or UE, but may also be used for other types of wireless nodes, such as relay or repeater nodes.

Full duplex operation needs to overcome several challenges in order to work in a practical deployment. When overlapping frequency resources are used, the received signal is affected by co-channel CLI and self-interference. CLI and self-interference cancellation methods include passive methods that rely on isolation between a transmit antenna and a receive antenna, active methods that utilize RF or digital signal processing, and hybrid methods that use a combination of active and passive methods. Filtering and interference cancellation may be implemented in RF, baseband (BB), or both RF and BB. While mitigating co-channel CLI may require a large complexity at the receiver, it is feasible within current technical limitations. Another aspect of FD operation is to mitigate adjacent channel CLI, because in several cellular band allocations, different operators have adjacent spectrum.

Throughout this disclosure, cross-division-duplex (XDD) is used as a short form of FD operation. The terms XDD and FD are used interchangeably in this disclosure.

FD operation in NR can improve spectral efficiency, link robustness, capacity and latency of UL transmissions. In an NR TDD system, UL transmission is limited by fewer available transmission opportunities than DL reception. For example, for NR TDD with scs=30 kHz, DDDU (2 ms), DDDSU (2.5 ms) or DDDDDDDSUU (5 ms), UL-DL configuration allows DL to UL ratio from 3:1 to 4:1. Any UL transmission can only occur in a limited number of UL slots, for example every 2, 2.5 or 5 milliseconds, respectively.

Fig. 11 illustrates two example FD configurations according to an embodiment of the present disclosure. The diagram 1100 is for illustration only, and other embodiments may be used without departing from the scope of the present disclosure.

For FD-enabled single carrier TDD configurations, the time slot denoted X is an FD or XDD time slot. Both DL and UL transmissions may be scheduled in XDD slots of at least one or more symbols. The term XDD slot is used to refer to a slot in which a UE can simultaneously receive and transmit in at least one or more symbols of the slot if the base station schedules or allocates radio resources. The half duplex UE cannot transmit and receive simultaneously in the XDD slot or on the symbol of the XDD slot. When a half-duplex UE is configured to transmit in the symbols of an XDD slot, another UE may be configured to receive in the symbols of the XDD slot. The FD UE may transmit and receive simultaneously in the symbols of the XDD slot, and there may be other UEs scheduling or allocating resources for DL or UL in the symbols of the XDD slot. The transmission of the UE in the first XDD slot may use the same or different frequency domain resources as in the second XDD slot, where the resources may differ in terms of bandwidth, location of the first RB or center carrier.

For FD-enabled dual carrier (carrier aggregation) TDD configurations, the UE receives in a slot on CC #1 and transmits in at least one or more symbols of a slot on CC # 2. FD slots having both transmission/reception by the gNB or UE, which occur on the same time domain resources (such as slots or symbols), are denoted by X, except for D slots for transmission/reception by the gNB/UE only, U slots for reception/transmission by the gNB/UE only, and S slots for supporting DL-UL handover as well. For the example of TDD with scs=30 kHz, single carrier and UL-DL allocation DXXSU (2.5 ms), the second and third slots allow FD operation. UL transmissions may also occur in the last time slot (U) where full UL transmission bandwidth is available. The XDD slot or symbol allocation over the time period/slots may be indicated by the DCI format in PDCCH reception and may then be changed per unit time period, or may be indicated by higher layer signaling, such as via MAC CE or RRC.

Although fig. 6-11 illustrate diagrams, various changes may be made to diagrams 600-1100 of fig. 6-11. For example, while some diagrams (such as diagrams 700, 800, and 900) describe subheaders and other diagrams (such as diagram 1000) describe a certain slot structure, various components may be combined, further subdivided, or omitted, and additional components may be added according to particular needs.

Embodiments of the present disclosure allow for robust network operation requiring that a UE be able to establish a connection to a network over a large coverage area without consuming significant resources and without requiring large delays to establish the connection. Accordingly, embodiments of the present disclosure contemplate the need to increase the signal-to-interference-and-noise ratio (SINR) of PRACH reception at the gNB in order to increase PRACH coverage. Embodiments of the present disclosure also contemplate the need to dimension PRACH capacity in a cell area to achieve a target collision probability for PRACH transmissions from a UE for an expected number of concurrent multiple access attempts by the UE. Embodiments of the present disclosure also contemplate the need to reduce the delay due to UL-DL frame alignment delay during the RA procedure, which represents the delay until the next PRACH transmission opportunity occurs.

The PRACH transmission requires several operational limitations when considering that the UE needs to transmit multiple channels and signals. RBs in UL slots or symbols fully or partially occupied by transmission of PRACH preambles are typically not available for other transmissions, such as for PUSCH. For example, in NR, transmission of a short PRACH preamble prevents m×12 RBs per RO in Frequency Division Multiplexing (FDM) from being used for PUSCH transmission. For a 15kHz SCS, the long preamble occupies m×6 or m×24 RBs, and for a 30kHz SCS, the long preamble occupies m×3 or m×12 RBs, where m=1 …. The first result is a decrease in the absolute number of schedulable UL RBs in UL slot (U) and a corresponding decrease in UL peak data rate. The second result is that PUSCH transmissions cannot be allocated a large contiguous BW depending on the placement of RACH Opportunities (ROs) in the carrier bandwidth. In NR Rel-15, the UE is forced to support only UL resource allocation type 1 requiring frequency continuous PUSCH allocation. Thus, PUSCH frequency allocation can only be completely lower or completely higher than PRACH allocation BW, and PUSCH cannot be scheduled in frequency across ROs. Even if UE implementation complexity is increased to support UL resource allocation type 0 using Resource Block Group (RBG) based allocation, additional power backoff up to several dB is required for corresponding PUSCH transmission. This results in a significant data rate reduction due to the lower SINR operating point.

Various embodiments of the present disclosure address the above-described issues by implementing PRACH transmission in FD time domain resources, such as in slots or symbols that are received and transmitted while supporting a UE or a gNB.

Fig. 12 shows an example diagram 1200 of RACH configuration using XDD in accordance with an embodiment of the disclosure. The diagram 1200 is for illustration only, and other embodiments may be used without departing from the scope of the disclosure.

The PRACH preamble transmission is configured in the third and fourth XDD slots in addition to the last UL slot (U), as shown in fig. 12. In general, the RA procedure related transmissions may be enabled in the symbols of the XDD slot, including some or all of Msg1 to Msg4 and possibly repetition. The first PRACH transmission in the XDD slot may be followed by a second PRACH transmission in the UL slot (U), or vice versa.

The first motivation to place PRACH transmissions in XDD slots, either fully or partially, is to increase the data rate in U slots, because the absolute number of schedulable RBs is increased, and a large number of consecutive RBs can be allocated to the UE by removing the RBs allocated to the PRACH preamble. The second motivation is to have a larger capability of contiguous RB allocation for PRACH transmission. For TDD and scs=30 kHz, only a short PRACH preamble format may be used when a single UL slot (U) is available. Longer PRACH preamble formats necessarily require more than one slot. By allowing PRACH transmission in N consecutive slots (such as n=2 or n=4 slots) including XDD slots and also UL slots, a long PRACH preamble format may be used, thereby increasing the range and achievable accuracy of timing estimation for PRACH reception. The third mobile is to reduce the complexity of the base station. When one or more UEs transmit respective PUSCHs in XDD slots, interference cancellation from DL signals needs to be designed to receive UL signals that may have substantially different transmission bandwidths or MCS settings, such as for receiving PUSCHs from different UEs, which may be at different power levels at the base station receiver or use different MCSs for the corresponding transport blocks. The transmission of the PRACH preamble in the XDD slot requires that the base station only performs interference cancellation based on one specific signal type, such as the Zadoff-Chu sequence used as the PRACH preamble, thereby simplifying the implementation of interference cancellation. The fourth motivation is that PRACH resources are used only when the UE actually transmits the respective PRACH even when the PRACH resources are configured in XDD slots. In several cases, depending on the RACH dimension, PRACH transmission does not occur in XDD slots where the PRACH transmission is configured. Therefore, the provision of PRACH resources in XDD slots does not generally produce DL-UL interference.

Embodiments of the present disclosure contemplate that several problems of the state of the art need to be overcome when considering resource selection and parameterization in the time, frequency and power domains of PRACH resources with FD operation in XDD slots.

The first problem relates to the need to consider different link conditions for the Msg1 and Msg3 transmissions in the normal UL and XDD slots. These different reception conditions at the gNB are due to antenna and panel design and deployment constraints. The number of TRX chains for transmission or reception, or the area for the transmission or reception antennas available in the normal DL or UL slots and XDD slots may be different between the FD embodiment and the half duplex embodiment. This is due to antenna design constraints in FD operation in order to achieve sufficient spatial isolation between Tx and Rx antenna ports. For example, reception at a base station in a normal UL slot may benefit from using a 32TRX of a 12Vx8Hx2P panel of size 40 x 60cm, while reception at a base station in an XDD slot may use only 16TRX and a component or panel of half the size in the UL slot.

The second problem relates to the use of normal (such as full) UL slots and XDD slots by the UE when performing the RA procedure. Due to different link conditions, the normal UL slot and XDD slot may be expected to use different RACH configurations. RACH configurations provided for use in XDD slots may support smaller UL link budget and/or higher Rx preamble target power than RACH configurations provided for normal UL slots. For example, the RACH configuration may differ in terms of preamble format and number of time domain RACH opportunities per RACH configuration period. A UE starting PRACH preamble transmission in an XDD slot may complete PRACH preamble retransmission using a normal UL slot. The UE attempting RA in the XDD slot should still be able to perform RA in the normal UL slot even when RA in the XDD slot fails. Similarly, UEs that do not support RA in XDD slots should not be negatively affected when XDD optimized UEs start or continue their RA transmission in normal (such as full) UL slots.

A third problem relates to the timeline for RA procedure for Msg2 and Msg4 when XDD or FD is used on the NR carrier. After the preamble transmission (Msg 1), the UE needs to receive the RAR (Msg 2) within a RAR window, which currently has a maximum setting of 80 slots for a 4-step RA procedure and 320 slots for a 2-step RA procedure. For scs=0 kHz and 4-step RA procedure, 80 slots correspond to 40 ms or 4 radio frames. After Msg3 transmission, the UE starts a contention resolution timer with a maximum possible setting of 64 subframes or 64 milliseconds (for 4-step and 2-step RA). When the contention resolution timer expires, the UE declares contention resolution as failed, and performs RA again if the number of RA attempts does not reach an upper limit. Up to 200 RA preamble transmission attempts may be configured. While in the rrc_idle state or the rrc_inactive state, the UE determines DL initial BWP using a bandwidth of CORESET #0 indicated by a master information bit (Master Information Bit, MIB) of the SSB. Only after receiving Msg4, the UE applies DL initial BWP acquired from SIB1 before RA. RAR (Msg 2) and Msg4 are transmitted within the Rx bandwidth set by CORESET#0. The UL initial BWP may be set to a different BW when compared to the DL initial BWP, but its center frequency must be aligned with the DL BWP used by the UE for TDD operation. Thus, constraints may arise when XDD or FD is used on the NR carrier. Depending on the configured NR channel bandwidth, the size and frequency location of the XDD subbands and CORESET #0, DL scheduling of Msg2 and Msg4 is hindered. In some slots, DCI format 1_0 scheduling PDSCH for RAR (Msg 2) or PDSCH for Msg4 cannot be transmitted at all or can be transmitted only using a small aggregation level.

Various embodiments of the present disclosure address the above-described problems and provide additional design aspects for supporting RA procedures, in which some or all of the associated messages are transmitted in whole or in part in XDD slots, and provide solutions as fully set forth below.

The present disclosure contemplates methods for PRACH preamble transmission and backoff procedures, UL transmit power control during RA, backoff procedures during RA, and timing and length of RAR reception and monitoring windows.

Although fig. 12 shows an example diagram 1200, various changes may be made to fig. 12. For example, while the diagram 1200 depicts a PRACH configuration, various components may be combined, further subdivided, or omitted, and additional components may be added according to particular needs.

Embodiments of the present disclosure describe methods for PRACH preamble transmission, UL transmit power control, backoff procedures, and timing and length of RAR reception and monitoring windows for UEs in a wireless system supporting FD during RA. The following concepts are described: (i) Using DELTA_ PREAMBLE, PREAMBLE _POWER_RAMPING_STEP, P _{C_MAX} A transmit power adjustment value and power increase procedure for RACH transmission in XDD or FD slots, preambleReceivedTargetPower, referenceSignalPower, etc., (ii) a back-off procedure from/to RA in XDD (or FD) slots; a detailed procedure including adjusting or resetting the accumulated power increase variables, preamble counter and signaled open loop settings, (iii) a backoff procedure from 2-step RACH, 4-step RACH/to 2-step RACH, 4-step RACH from/to XDD or full UL slot during RA, and (iv) separate configuration for RAR window size and monitoring window when RA is used in XDD or FD slots; obtained from signaling or scaling.

In the following and throughout the disclosure, some configurations, scheduling, or resource allocations of a gNB (such as BS 102) may assume that a UE (such as UE 116) is known in the gNB to support XDD-specific provisioning. For example, the UE may signal to the gNB through a UE capability query (Capability Enquiry) procedure that the UE supports XDD specific provisioning. The gNB may also signal XDD specific configuration, scheduling or resource allocation using common DL signaling such as SI. When using asn.1 extensions, UEs not supporting asn.1 extensions will ignore such configurations, whereas UEs supporting XDD specific provision may use one or both of legacy/non-XDD and XDD configurations. The gNB may also derive knowledge of the XDD specific specifications supported by the UE, as the UE uses a set of specified and known (for the gNB) XDD radio resources.

In some embodiments, the UE determines a different UL power control setting for RA transmission in the XDD slot when compared to the normal UL slot. These different power control settings are determined using different open loop parameters and/or different power-control steps. During RA, a different power increase step size, power increase counter and/or preamble counter is applied for XDD slots UEs compared to normal UL slots.

In certain embodiments (such as those described in fig. 13 and 14), a UE configured with an RA using an XDD slot or symbol determines an XDD POWER adjustment value when calculating a preamble_reception_target_power for transmitting a PRACH PREAMBLE. The UE may apply the XDD POWER adjustment value when determining delta_preamble or preamble_power_ramp_step.

The XDD power adjustment value may be tabulated (tabuloated) and provided by the system specification, or may be signaled to the UE using a common or dedicated RRC message or MAC CE. The XDD power adjustment value may be signaled as an index value in a set of tabulated or configured values to derive the setting. The XDD POWER adjustment value may be determined as a relative adjustment value instead of providing an absolute value, wherein a first delta_preamble or preamble_power_ramp_step derived from an existing configuration is obtained and offset by an XDD POWER adjustment factor to obtain a value for PRACH PREAMBLE transmission. Multiple XDD power adjustment values may be available. The selection of the appropriate XDD power adjustment value may be determined by one or more UEs depending on the SCS, preamble format, time domain allocation of transmission resources, and parameters of the network control. The XDD power adjustment value may be adopted as part of one or more other correction factors.

In one example, the UE uses the XDD power adjustment value to determine the value of delta_preamble as a set of tabulated values, such as shown in table (4) and table (5). The current lead code transmission counter is larger than 1; and setting a value of delta_preamble according to the tabulated value when the selected SSB or csi_rs is unchanged from the last RACH PREAMBLE transmission. More than one tabulated set of values may be used.

Table (4) describes the XDD power adjustment as delta_preamble value for the long PREAMBLE format, and table (5) describes the XDD power adjustment as delta_preamble value for the short PREAMBLE format.

[ Table 4 ]

Preamble format	DELTA_PREABLE value
		0	3dB
1	0dB
		2	-3dB
3	3dB

[ Table 5 ]

Preamble format	DELTA_PREABLE value (dB)
		A1	11+3×μ
A2	8+3×μ
		A3	6+3×μ
B1	11+3×μ
		B2	8+3×μ
B3	6+3×μ
		B4	3+3×μ
C0	14+3×μ
		C2	8+3×μ

In another example, the UE determines the delta_preamble value from existing tables, such as the shown table (1) and table (2), using the XDD power adjustment value. When preamble_transmission_counter is greater than 1 and the selected SSB or csi_rs is unchanged from the last RACH PREAMBLE TRANSMISSION, the delta_preamble value is determined from tabulated values such as shown in table (1) and table (2) and the XDD adjustment value. For example, for PREAMBLE formats A1 and scs=30khz, the ue determines a delta_preamble value of 11 dB. The UE calculates the PREAMBLE transmission power by adjusting the DELTA _ PREAMBLE value of 11dB by the XDD power adjustment value of 3dB to obtain a value of 14 dB. The relative XDD power adjustment value may be one or more sets, possibly depending on one or more SCS, or preamble format, or transmission resource allocation.

In another example, the UE uses the XDD POWER adjustment value to determine the value of preamble_power_ramp_step. When RA is initiated on the serving cell, the UE sets the preamble_power_ramp_step to a signaled or tabulated value for RA transmission in XDD slots or symbols. For example, the UE obtains the signaled parameter powerramsingstepfd (power increase step FD) by common or dedicated signaling (such as RRC), where FD stands for full duplex. UE sets preamble_power_ramp_step to powerramp stepfd. A plurality of signaled values may be configured. The selection of the appropriate XDD power adjustment value may be determined by the UE depending on the SCS, preamble format, time domain allocation of transmission resources and network controlled parameters. The XDD POWER adjustment value that determines the PREPARATORE RAMPING STEP may be adopted as part of one or more other correction factors, such as, for example, the msgA-PreamblePowerRampingStep of a 2-STEP RA procedure.

In another example, the XDD POWER adjustment value used by the UE to determine the value of preamble_power_ramp_step is applied as an offset or relative value. An existing configuration (such as the signaled parameter powerramingstep) is obtained and offset by an XDD power adjustment factor to obtain a value for PRACH preamble transmission. For example, for the parameter powerramsingstep, the setting of dB4 (or 4 dB) may be signaled to the UE. The UE determines a value of 7dB for preamble_power_ramp_step using the first signaled 4dB value and the second XDD POWER adjustment value of x=3 dB. Multiple XDD power adjustment values may be available. The selection of the appropriate XDD power adjustment value may be determined by one or more UEs depending on the SCS, preamble format, time domain allocation of transmission resources, and parameters of the network control. The XDD power adjustment value may be adopted as part of one or more other correction factors.

Fig. 13 shows an example diagram 1300 of a PRACH preamble transmission sequence according to an embodiment of the disclosure. Fig. 14 illustrates an example method 1400 of a PRACH transmission processing chain in accordance with an embodiment of the disclosure. The diagram 1300 and method 1400 are for illustration only, and other embodiments may be used without departing from the scope of the disclosure. The steps of method 1400 of fig. 14 may be performed by any of UEs 111-116 of fig. 1 (such as UE 116 of fig. 3). The diagram 1300 and method 1400 are for illustration only, and other embodiments may be used without departing from the scope of the disclosure.

As shown in fig. 13, the RACH period is 10 milliseconds. DDXXDDDSUU is configured using scs=30 kHz and UL-DL exceeding 5 ms. UEs that do not support XDD use PRACH access cells configured in normal UL slots. The XDD UE uses PRACH configured in XDD slots #2 and # 3. The power up sequence for a UE that does not support XDD is shown as case a. The power up sequence for XDD UEs is shown as case B. Between the first and second retransmissions of the PRACH PREAMBLE, when the preamble_received_target_power is calculated using delta_preamble and/or preamble_power_ramp_step for a given PRACH transmission, the XDD UE (case B) determines a different PRACH PREAMBLE transmission POWER by using the XDD POWER adjustment value compared to the UE (case a) that does not support XDD.

As shown in fig. 14, an example PRACH transmission processing chain according to an embodiment of the disclosure. The UE determines the requirements of the RA procedure. If the selected RA radio resources include XDD or FD radio resources, the UE determines an XDD adjustment value from the signaled or tabulated values and possibly subject to transmission conditions, such as SCS. The UE determines the value of the PRACH preamble power increase step size by considering the XDD adjustment value. When setting the value of the power increase step size, a plurality of adjustment values may be considered. The UE determines a value of PRACH reception target power and transmits the PRACH. A similar PRACH transmission processing chain may be used when DELTA _ PREAMBLE is used to consider the XDD adjustment value.

In step 1410, a UE (such as UE 116) determines that an RA is triggered. In step 1420, the UE determines a time domain allocation of PRACH resources. In step 1420, the ue also determines whether the PRACH is transmitted in XDD resources. In response to determining that the PRACH is transmitted in the XDD resource (as determined in step 1420), the UE determines an XDD power adjustment value in step 1430.

In STEP 1440, the UE determines the value of the variable preamble_power_ramp_step from the signaled value powerramp STEP and the adjustment STEP. In step 1450, the ue determines the value of the variable previous_receive_voltage_target_power.

Although fig. 13 illustrates diagram 1300, fig. 14 illustrates method 1400, various changes may be made to fig. 13 and 14. For example, while method 1400 is illustrated as a series of steps, the various steps may overlap, occur in parallel, occur in a different order, or occur multiple times. In another example, steps may be omitted or replaced with other steps. For example, the steps of method 1400 may be performed in a different order.

In certain embodiments (such as those described in fig. 15 and 16), a UE (such as UE 116) configured with an RA using symbols in the XDD slots uses the second PRACH transmit power parameter set to determine the PRACH transmit power. The first PRACH transmit power parameter set may be configured for RA in a normal (such as complete) UL slot. When at least one RA transmission occurs in a symbol of an XDD slot, a second PRACH transmit power parameter set, such as XDD, is used. The PRACH transmit power parameter set may include one or more of (i) P-Max, (ii) preablereceivedtargetpower, and (iii) preferenceignignalpower. Here, P-Max is an allowable UL transmission power value configured for the UE; may be per carrier, per BWP, per serving cell, or for transmission opportunities. Preamblyreceivedtargetpower is the target PRACH receive power value. In addition, reference signaling power is the reference signal transmit power signaled by the base station to the UE for determining path loss in active BWP; the path loss determination of the UE may be associated with L1 and higher layer filter configurations.

The XDD PRACH transmit power parameter set may be tabulated and provided by the system specification, or may be signaled to the UE using a common or dedicated RRC message or MAC CE. The XDD PRACH transmit power parameter set may be signaled as an index value in a set of tabulated or configured values to derive the settings. The XDD PRACH transmit power parameter set may be determined as a relative adjustment value compared to a first PRACH transmit power parameter set, which is derived from an existing configuration, and then offset by an XDD adjustment factor to obtain a value for PRACH preamble transmit power. Multiple XDD values or a set of transmission power parameters for the XDD PRACH may be available. The selection of the appropriate XDD PRACH transmission power value is determined by one or more UEs in dependence on the SCS, the preamble format, the time domain allocation of transmission resources and the parameters of the network control. The XDD PRACH transmit power value may be adopted as part of one or more other correction factors.

In one example, in XDD or FD transmission opportunity i, the UE uses P-Max to determine the transmission power P for PRACH on the active UL BWP b for carrier f of serving cell c based on DL RS for serving cell c _PRACH,b,f,c (i) A. The invention relates to a method for producing a fibre-reinforced plastic composite For RA transmission, the P-Max value of the XDD slot or symbol is signaled. For example, the UE obtains the signaled parameter P-Max-FD by common or dedicated signaling (such as RRC), where FD stands for FD. UE set P _PRACH,b,f,c (i) The smaller of the sum of PRACH target received power and path loss calculated for (a) configured P-Max-FD and (b). A plurality of signaled values may be configured. The selection of the appropriate maximum configured or allowed transmission power may be determined by one or more UEs depending on the SCS, preamble format, time domain allocation of transmission resources and network controlled parameters.

In another example, the UE uses the preamble received dtargetpower in XDD or FD transmission opportunity i to determine the transmission power P for PRACH on the active UL BWP b of carrier f of serving cell c based on DL RS for serving cell c _PRACH,b,f,c (i) A. The invention relates to a method for producing a fibre-reinforced plastic composite For RA transmission, the value of the preamp receivedtargetpower for the XDD slot or symbol is signaled. For example, the UE obtains signaled parameters through common or dedicated signaling (such as RRC)A preamble reception target power FD (FD), where FD stands for FD. UE set P _PRACH,b,f,c (i) The smaller of the sum of the preampletereceivedtargetpowfd and the path loss calculated for (a) configured P-Max and (b). A plurality of signaled values may be configured. The selection of the appropriate preablereceivedtargetpower may be determined by the UE depending on the SCS, preamble format, time domain allocation of transmission resources and network control parameters.

In another example, in XDD or FD transmission opportunity i, the UE uses the reference signaling power to determine the transmission power P for PRACH on the active UL BWP b of carrier f of serving cell c based on DL RS for serving cell c _PRACH,b,f,c (i) A. The invention relates to a method for producing a fibre-reinforced plastic composite For RA transmission, the value of the reference signalpower of the symbol of the XDD slot is signaled. For example, the signaled parameter, referenceSignalPower, is signaled by ss-PBCH-BlockPower. In the symbols of the XDD slot, the UE is provided with a different value of ss-PBCH-BlockPower for RACH transmission when compared to the normal (such as complete) UL slot. UE set P _PRACH,b,f,c (i) The smaller of the sum of the preambleReceivedTargetPower and the path loss calculated for (a) configured P-Max and (b). For the same RSRP measurement derived from SSB or CSI-RS, the UE uses different signaled ss-PBCH-BlockPower values to calculate different values of path loss in XDD slots or symbols. It is also possible to use the same ss-PBCH-BlockPower value for XDD and normal UL slots, but apply the correction value by a relative offset value. For example, the UE obtains powercontrol offsetfd (power control offset FD) by common or dedicated signaling (such as RRC), where FD stands for FD. A plurality of signaled values may be configured. The selection of the appropriate reference signalpower may be determined by one or more UEs depending on the SCS, preamble format, time domain allocation of transmission resources, and parameters of network control.

Fig. 15 shows an example diagram 1500 of PRACH preamble transmission sequences in accordance with an embodiment of the disclosure. Fig. 16 illustrates an example method 1600 of a PRACH transmission processing chain according to an embodiment of this disclosure. The diagram 1500 and method 1600 are for illustration only, and other embodiments may be used without departing from the scope of the present disclosure. The steps of method 1600 of fig. 16 may be performed by any of UEs 111-116 of fig. 1 (such as UE 116 of fig. 3). The diagram 1500 and method 1600 are for illustration only, and other embodiments may be used without departing from the scope of the present disclosure.

As shown in fig. 15, an example PRACH preamble transmission sequence according to an embodiment of the present disclosure. The RACH period is 10 milliseconds. DDXXDDDSUU and scs=30 kHz are configured using UL-DL. UEs that do not support XDD use PRACH access cells configured in normal UL slots. The XDD UE uses PRACH configured in XDD slots #2 and # 3. The power up sequence for a UE that does not support XDD is shown as case a. The power up sequence of the XDD UE is shown as case B. For the first transmission of the PRACH preamble, the XDD UE (case B) determines a lower PRACH preamble transmission power than the UE (case a) that does not support XDD by using a preambleReceivedTargetPower value configured low in the XDD slot. Already in the second retransmission, the XDD UE (case B) has reached the maximum allowed configured P-MaxFD transmission power and the PRACH preamble power is not further increased in the third retransmission attempt, whereas the UE that does not support XDD (case a) and is configured with a different setting may further increase the preamble transmission power.

The method 1600 describes an example PRACH transmission processing chain in accordance with an embodiment of the present disclosure. The UE determines that an RA procedure needs to be initiated. If the selected RA radio resources include XDD or FD radio resources, the UE determines the XDD maximum configured transmit power value from the signaled or tabulated values and may be conditioned on transmission conditions, such as XDD transmission bandwidth or resource allocation in the frequency domain. The UE determines a value of PRACH transmission power by considering the maximum allowable XDD transmission power value. When setting the value of the power increase step size, a plurality of adjustment values may be considered. The UE determines a value of PRACH transmission power and transmits the PRACH.

In particular, in step 1610, the UE determines that RA is triggered. In step 1620, the UE determines a time domain allocation of PRACH resources. In step 1620, the ue also determines whether the PRACH is transmitted in XDD resources. In response to determining that the PRACH is transmitted in the XDD resource (as determined in step 1620), the UE determines P-MaxFD (step 1630). Optionally, at the UEAfter determining the P-MaxFD (step 1630), or in response to determining that the PRACH is sent in XDD resources (as determined in step 1620), in step 1640 the UE determines P _PRACH,b,f,c (i) Is a value of (2).

The motivation is for the UE to adjust the received power level at the base station during the RA procedure in the XDD slot. When PRACH transmissions are received in normal/complete UL slots, the base station may process PRACH detection without any DL interference, thereby maximizing UL coverage and using complete processing gain at the base station. The PRACH transmission received and processed by the base station in the symbols of the XDD slot may be subject to Rx power constraints, considering the interference cancellation capability of the base station. Furthermore, by using a separate power setting in the FD system, it may be helpful to control UL-DL cross link interference generated by a UE transmitting a PRACH preamble and affecting UEs received in the DL portion of the XDD slot.

Although fig. 15 illustrates fig. 1500, fig. 16 illustrates method 1600, various changes may be made to fig. 15 and 16. For example, although method 1600 is illustrated as a series of steps, the various steps may overlap, occur in parallel, occur in a different order, or occur multiple times. In another example, steps may be omitted or replaced with other steps. For example, the steps of method 1600 may be performed in a different order.

In some embodiments (such as those described in fig. 17 and 18), when the maximum number of retransmission attempts using XDD resources has been reached, a UE configured with RA using the symbols of the XDD slots falls back to RA using normal (such as complete) UL slots. Alternatively, when a timer value is reached or when specified signal conditions are met, the UE backs off and attempts to use RA of the normal (such as full) UL slot. The signal condition may include an RA transmission power value determined by the UE or a signaling message received through or associated with the PDCCH, such as PDSCH carrying RAR (Msg 2) and MAC (sub) header. The backoff procedure may be applied to a 2-step or 4-step RACH procedure, and is explained below by way of example using a 4-step RACH procedure.

The XDD counter or timer or signal power condition value may be tabulated and provided by the system specification, or may be signaled to the UE using a common or dedicated RRC message or MAC CE. The XDD counter or timer or signal power condition value may be signaled as an index value in a set of tabulated or configured values to derive the setting. The XDD counter or timer or signal power condition value may be determined as a relative adjustment value, wherein a first parameter derived from an existing configuration is obtained and then offset or scaled by an XDD adjustment factor to obtain a value for the XDD counter or timer or signal power condition value. Multiple XDD counters or timers or signal power condition values may be available. The selection of the appropriate XDD counter or timer or signal power condition value is determined by one or more UEs in dependence on the SCS, preamble format, time domain allocation of transmission resources and network controlled parameters. The XDD counter or timer or signal power condition value may be adopted as part of one or more other correction factors.

In one example, the UE is configured with a preamble transmission maximum FD (FD) value, where FD represents FD transmission. When attempting RA (transmit PRACH) using XDD or FD radio resources, the UE increases the counter for each PRACH preamble transmission attempt on the XDD or FD RACH opportunity. If the counter reaches the value of the preambamoxfd, the UE reselects RA resources from only the set of configured RACH opportunities in a normal (such as complete) UL slot. The UE then retries the RA using the set of RACH opportunities that occurred in the normal UL slot. The preamble format may change when the UE reselects the RACH opportunity in the normal UL slot. Similarly, as described in other embodiments of the present disclosure, the UE may adjust the current or accumulated counter or transmission power value. The value for preambamoxfd, such as the maximum allowed number of PRACH preamble transmission attempts, may be signaled by RRC as a value independent of the maximum allowed number of PRACH transmission attempts (preamble transmission maximum) valid for a normal UL slot. It is also possible that the UE derives the value of preambmantransmaxfd by scaling the value of preambmantransmax that is valid for the normal UL slot. For example, the UE may be configured to use up to floor (M x preableTransMax) PRACH preamble transmission attempts using XDD slots, where M is a scaling factor, e.g., M=1/2.

In another example, the UE is configured with a rachtmerfd (rach timer FD) timer value, where FD represents FD transmission. When attempting RA using XDD or FD radio resources, the UE increases the timer while RACH UL transmission and/or DL reception is ongoing. The timer may count time units, such as samples, slots, subframes, frames, or a plurality thereof. Without loss of generality, the UE may start a timer, such as the start of a first or initial PRACH preamble transmission, upon occurrence of an identified transmission condition. The UE may stop the timer upon occurrence of an identified condition, such as receiving Msg2 or successfully stopping the RA procedure, such as after successfully receiving Msg 4. If the timer reaches the value of rachtmerfd, the UE reselects RA resources from only the set of configured RACH opportunities in a normal (such as complete) UL slot. The UE then retries RA (PRACH transmission) using the set of RACH opportunities that occurred in these normal UL slots. The preamble format may change when the UE reselects the RACH opportunity in the normal UL slot. Similarly, as described in other embodiments of the present disclosure, the UE may adjust the current or accumulated counter or transmission power value. The value for rachtmerfd (such as the time allowed for RA attempting to use XDD slots or radio resources) may be signaled by RRC.

In another example, the UE is configured with a rachMaxPowerFD (rach maximum power FD) value, where FD represents FD transmission. When attempting RA (PRACH transmission) using XDD or FD radio resources, the UE increases PRACH transmission POWER during each PRACH PREAMBLE transmission attempt using preamble_power_ramp_ COUNTER, DELTA _preamble and preamble_power_ramp_step on XDD or FD RACH occasions. If the transmission power reaches the value of rachmaxowerfd, the UE reselects RA resources from only the set of configured RACH opportunities in the normal (such as complete) UL slot. The UE then retries the RA using the set of RACH opportunities that occurred in the normal UL slot. The preamble format may change when the UE reselects the RACH opportunity in the normal UL slot. Similarly, as described in other embodiments of the present disclosure, the UE may adjust a current or accumulated counter orTransmission power value. The value for rachMaxPowerFD (such as the maximum allowed PRACH preamble transmission power level) may be signaled by RRC. It is also possible that the value of the preambransmaxfd may be signaled and then signaled by the UE by a reference to a known reference value (such as P _c,max ) Scaling or applying offset value derivation. For example, the UE may be configured with an offset or power reduction (power reduction) value of m=6 dB. The UE determines the maximum allowed PRACH preamble transmission power for XDD slots as P _c,max M, in dB.

In another example, the UE attempts RA (PRACH transmission) using XDD or FD radio resources. After the PRACH preamble transmission attempt, the UE monitors the PDCCH to determine the presence of the RAR, thereby confirming that the gNB successfully received the PRACH preamble transmission. For example, the received PDCCH contains DCI format 1_0 with ra_rnti scrambled by the time and frequency resources associated with the PRACH opportunity in which the UE transmitted the PRACH preamble. PDSCH scheduled by DCI format 1_0 provides signaling indication for UE to continue RA procedure using normal (such as full) UL slots. For example, the fallbackRAR may be used to redirect the UE for RA in normal UL slots or symbols. For example, the signaling indication may be encoded as one or more bits or codepoints in a MAC header or MAC subheader or RAR payload. Alternatively, the signaling indication may be encoded as part of the payload of DCI format 1_0. In one exemplary technical implementation, the signaling indication consists of a single bit that, when set, indicates to the UE that any further PRACH preamble transmission attempts are by using normal (such as full) UL resources. It is also possible that the signaling bit, when set, indicates that XDD or FD resources are allowed to be used during a later RA attempt. The signaling indication may be associated with other information that controls further PRACH preamble transmission attempts by the UE. For example, the signaling indication may contain a maximum number of PRACH retransmission attempts, or a required or allowed power level or transmission parameter associated with XDD or FD radio resources. The signaling indication may also be encoded using the code points from the existing IE or field, MAC header or sub-header, or PDSCH payload of the DCI format. Upon receiving the back-off signaling indication, the UE continues transmission for the RA procedure using the indicated mode of operation. For example, if the signaling indicates that further use of XDD or FD resources during RA is prohibited, the UE backs off to RA using normal UL slots.

Fig. 17 shows an example diagram 1700 of a PRACH preamble transmission backoff sequence according to an embodiment of the present disclosure. Fig. 18 illustrates an example method 1800 of PRACH transmission backoff processing chain according to an embodiment of the disclosure. The diagram 1700 and the method 1800 are for illustration only, and other embodiments may be used without departing from the scope of the present disclosure. The steps of method 1800 of fig. 18 may be performed by any of UEs 111-116 of fig. 1 (such as UE 116 of fig. 3). The diagram 1700 and the method 1800 are for illustration only, and other embodiments may be used without departing from the scope of the present disclosure.

Fig. 17 illustrates an example PRACH preamble transmission backoff sequence according to an embodiment of the present disclosure. The PRACH transmission period is 10 milliseconds. The UE is provided with a DDXXDDDSUU UL-DL configuration for active UL/DL BWP and 30kHz SCS. UEs that do not support XSS use PRACH access cells configured in normal UL slots. The XDD UE uses PRACH configured in XDD slots #2 and # 3. The power up sequence for a UE that does not support XSS is shown as case a. The power up sequence for XDD UEs is shown as case B. XDD UE is configured with preambransmaxfd=3. The XDD UE (case B) attempts 3 consecutive PRACH preamble transmissions using the XDD RA resource and fails to correctly receive the RAR. The XDD UE (case B) then backs off to using the normal UL resources configured as RACH opportunity for its fourth RACH preamble transmission attempt. In the particular example shown in fig. 17, the UE continues to use the PRACH preamble transmission power determined for the third preamble transmission in the XDD slot for RA transmission in the normal UL slot.

Fig. 18 illustrates an example PRACH transmission backoff processing chain according to an embodiment of the present disclosure. The UE determines that RA procedure needs to be performed. The UE selects RA radio resources among XDD or FD radio resources and determines the allowed maximum number of PRACH preamble transmission attempts using these radio resources. After each PRACH preamble transmission attempt, the UE increments a counter and compares the counter to the maximum allowed number. If the maximum allowed number has been reached, the UE reselects RA resources configured in a normal (such as complete) UL slot and continues the RA procedure.

In particular, in step 1810, a UE (such as UE 116) determines that an RA is triggered and the UE attempts the RA using an XDD slot. In step 1820, the ue determines whether the number of RACH preamble transmissions is greater than or equal to preambamx fd. In response to determining that the number of RACH preamble transmissions is greater than or equal to the preambambleTransMaxFD (as determined in step 1820), the UE reselects the RA resources configured in the normal (full) UL slot in step 1830. In step 1840, the UE continues RA using the normal (full) UL slot.

One motivation is that the UE first attempts RA using XDD or FD resources in the coverage area of the cell, where the received interference level and UL-DL cross link interference conditions favor FD operation. Any PRACH transmissions attempted by the UE are offloaded (offloaded) from a normal (such as complete) UL slot. PRACH detection by the base station may use the full SIC processing gain at the base station, if possible, depending on signal conditions. A UE that fails RA using configured XDD or FD resources may still benefit from UL coverage and cross-link or self-interference free (self-interference free) reception conditions in a normal UL slot.

Although fig. 17 illustrates a diagram 1700, fig. 18 illustrates a method 1800, various changes may be made to fig. 17 and 18. For example, while method 1800 is illustrated as a series of steps, the various steps may overlap, occur in parallel, occur in a different order, or occur multiple times. In another example, steps may be omitted or replaced with other steps. For example, the steps of method 1800 may be performed in a different order.

Fig. 19 illustrates an example method 1900 of a PRACH parameter backoff processing chain according to an embodiment of the disclosure. Fig. 20 illustrates an example method 2000 of determination of RA type in XDD or normal UL slots, according to an embodiment of this disclosure. Fig. 21 illustrates an example method 2100 of a backoff procedure from a 2-step RACH to a 4-step RACH in XDD and normal UL slots in accordance with an embodiment of the present disclosure. Fig. 22 illustrates an example method 2200 of determining a RAR window size according to an embodiment of the present disclosure. Method 1900, method 2000, method 2100, and method 2200 are for illustration only, and other embodiments may be used without departing from the scope of the present disclosure. The steps of method 1900 of fig. 19, method 2000 of fig. 20, method 2100 of fig. 21, and method 2200 of fig. 22 may be performed by any of UEs 111-116 of fig. 1 (such as UE 116 of fig. 3). Methods 1900-2200 are for illustration only, and other embodiments may be used without departing from the scope of the present disclosure.

In certain embodiments (such as those described below in fig. 19), switching from/to an RA using XDD slots or symbols to/from an RA using normal (such as complete) UL slots adjusts one or more of the following parameter values before re-attempting or continuing the RA procedure. The parameter values include (i) PREAMBLE INDEX; (ii) preamble_transmission_counter; (iii) pre_power_ramp_counter; (iv) pre_power_ramp_step; (v) pre-determined_received_target_power; (vi) preamble_back off; (vii) PCMAX; and (viii) scan_factor_bi (scale_factor_bi).

If a single parameter value is configured for RA in XDD slots or normal UL slots, the parameter value may be reset or reinitialized. Alternatively, the parameter values may be reserved and continue to be used during the backoff RA attempt in the normal UL slot. If two or more parameter values are configured, such as a first parameter value for RA in XDD slots and a second parameter value for RA in normal UL slots, the adjustment for any of these parameter values may depend on the considered parameter corresponding to one of the following adjustments. The parameter values are reset or reinitialized. The parameter values continue to be used during the rollback. It is possible that the larger of the two parameter values is used, or the smaller of the two parameter values is used, or the difference between the two parameter values is used.

In one example, the UE maintains preamble_transmission_counter when attempting RA (PRACH PREAMBLE TRANSMISSION) using XDD slots. A counter is incremented for each PRACH preamble transmission. When the configured maximum is reached, the UE rolls back to RA in the normal UL slot. The preamble_transmission_counter is maintained by the UE during backoff. If the preambbleTransMax value of the RRC configuration of n50 (or 50 times) is set for the RA configuration in the normal UL slot, the UE continues to attempt PRACH preamble transmission until the value is reached. For example, after the UE has tried the maximum number of allowed n10 (or 10 times) of PRACH preamble transmissions using XDD slots, the UE may continue to transmit RACH in a normal UL slot as much as (50-10) =40 times. Alternatively, separate values are used. After the UE fails RA on XDD slots due to reaching the maximum number of PREAMBLE TRANSMISSIONs, the UE reinitializes preamble_transmission_counter. The UE continues RA (PRACH transmission) in the normal UL slot until the maximum number of allowed PRACH preamble transmissions for the normal UL slot, such as possibly up to 50 times using the above example. A similar method can be applied to adjust the preamble_power_ramp_counter at the time of backoff.

In one example, the UE determines values for preamble_power_ramp_step and/or PCMAX when attempting RA (PRACH PREAMBLE transmission) using XDD slots. For PRACH PREAMBLE transmission, the UE uses preamble_power_ramp_step and/or PCMAX to calculate the allowed transmission POWER. When the UE reaches the maximum configured allowed transmission power, the UE cannot continue to increase the transmission power in subsequent access attempts. When the maximum value of the configuration of PRACH preamble retransmission using XDD slots is reached, the UE backs off to RA in the normal UL slot. During rollback, the preamble_power_ramp_step and/or PCMAX values may change or remain unchanged. For example, if the same PCMAX value is configured to be valid for RA in a normal UL slot, the UE maintains the value. When the UE changes the PREAMBLE format, such as from PREAMBLE format 0 in XDD slot to C0 in normal UL slot, the value for preamble_power_ramp_step may change. The UE continues to attempt PRACH preamble transmission after the backoff event using these parameter values.

In case the UE is configured with a set of more than one RACH configuration parameters for use in XDD slots and normal UL slots, respectively, the UE retrieves the RACH configuration set valid for that slot type at back-off. For example, when backing up to RA (PRACH preamble transmission) in a normal slot after a number of unsuccessful RA attempts in an XDD slot, the UE retrieves RACH configuration parameters for the normal UL slot from memory, determines a set of transmission variables as needed, and then attempts RA (PRACH preamble transmission) using new RACH parameter values.

A method 1900, as shown in fig. 19, describes an example PRACH parameter backoff processing chain in accordance with an embodiment of the present disclosure. The UE determines that a RACH opportunity in a normal UL slot needs to be used to perform backoff. The UE selects the maximum number of preamble transmission attempts in the normal UL slot. The UE maintains a preamble_transmission_counter. When the number of PRACH PREAMBLE TRANSMISSIONs is not greater than the current value of preamble_transmission_counter, the UE continues PRACH PREAMBLE TRANSMISSION in the normal UL slot until the maximum number of PREAMBLE TRANSMISSION attempts.

In particular, in step 1910, a UE (such as UE 116) backs off from XDD to normal UL slot during RA. In step 1910, the UE also determines preableTransMax for RA in the normal UL slot. In step 1920, the UE determines whether preamble_transmission_counter is less than PREAMBLE transmit max. In response to determining that preamble_transmission_counter is not less than PREAMBLE TransMax (as determined in step 1920), the UE declares an RA failure to the higher layer in step 1950. Optionally, in response to determining that preamble_transmission_counter is less than PREAMBLE transmit max (as determined in step 1920), the UE continues RA using RACH occasions in the normal UL slot in step 1930. In step 1940, the UE continues RA using a normal (such as complete) UL slot.

In certain embodiments (such as those described below in fig. 20 and 21), a UE configured with an RA using the symbols of the XDD slot determines whether to allow or enable a 2-step RACH and/or 4-step RACH procedure in the XDD slot. The UE may fall back from RA in XDD slots during a 2-step RACH or 4-step RACH procedure to/from 2-step RACH or 4-step RACH procedure in a normal UL slot to RA in XDD slots during a 2-step RACH or 4-step RACH procedure.

During RA in XDD slots or normal slots, if a 2-step RACH or 4-step RACH procedure is allowed or requested, the system configuration may be determined by the UE using configuration parameters, which are tabulated or provided by the system specification or signaled to the UE. For example, a common or dedicated RRC message or MAC CE may be used. Multiple settings may exist depending on the protocol state or RA trigger conditions. For example, the 2-step RACH procedure may be enabled or requested for XDD slots only in the rrc_connected mode, not in the rrc_idle mode. One or more UEs in parameters depending on time domain allocation of transmission resources, frequency domain radio resource allocation or network control may determine the selection of RACH procedure type. Some or all messages associated with a 2-step or 4-step RACH procedure may be enabled or requested in XDD slots or normal UL slots. For example, during RA, only Msg1 (4 steps) may be enabled in XDD slots, but during RA Msg3 may be enabled or requested to be sent in normal UL slots.

As described in other embodiments of the present disclosure, during RA in an XDD slot or a normal UL slot, a backoff from/to a 2-step RACH or a 4-step RACH procedure may be initiated by a counter, such as when the maximum number of RACH retransmission attempts using XDD or normal UL resources has been reached. Alternatively, when a timer value is reached or when specified signal conditions are met, the UE backs off and attempts to use RA of a different RA configuration. The signal condition may include an RA transmission power value determined by the UE or a signaling message received through or associated with the PDCCH, such as PDSCH carrying RAR (Msg 2) and MAC (sub) header.

In one example, the UE acquires and reads SIB1.SIB1 carries the RA configuration for the UE as part of the payload. The RA configuration indicates the use of a 4-step RACH ("type 1" procedure) using XDD slots, but allows the use of a 2-step RACH ("type 2" procedure) or a 4-step RACH using normal UL slots. When selecting an RA using the XDD slot from the RA configuration, the UE determines the RA type, e.g., 2-step RACH. The UE determines the RA type from the set of RA types allowed in the normal UL slot, e.g. 2-step or 4-step RACH. For example, in this case, the UE may select a 2-step RACH due to UE internal configuration preferences.

In another example, the UE acquires and reads SIB1 indicating that both 2-step RACH and 4-step RACH are allowed and available in a cell using XDD or normal UL slots. The UE determines the RA type from the set of RA types allowed in the XDD slot or the normal UL slot, for example, a 2-step or 4-step RACH. For example, due to UE internal configuration preferences, the UE may select a 2-step RACH for RA in the normal UL slot and a 4-step RACH in the XDD slot.

In another example, the network signaling indicates a RA procedure type for a request used in an XDD slot or a normal UL slot. The PDCCH order carries an RA procedure type indication that is explicitly or implicitly associated with XDD or normal UL radio resources. The UE sets an RA (e.g., a 2-step or 4-step RACH) and a radio resource type (e.g., an XDD slot or a normal UL slot) according to the received signaling indication and then continues the RA procedure using the determined configuration.

In another example, the UE selects a 2-step RACH procedure as the RA type in the XDD slot. The UE sends the MsgA preamble one or more times. When the UE determines that the RACH preamble transmission is unsuccessful, e.g., after reaching a configurable maximum number of MsgA preamble transmissions, and no RAR is decoded, the UE rolls back to the 4-step RACH procedure. The UE sets the RA type from 2-step RACH to 4-step RACH. The UE may reset or reinitialize or retain settings for some or all early (earlie) transmission variables, such as described in other embodiments of the disclosure. The UE then retries RA using XDD slots according to the 4-step RACH procedure.

In another example, the UE selects a 2-step RACH procedure as the RA type in the XDD slot. The UE sends the MsgA preamble one or more times. When the UE determines that the RACH preamble transmission is unsuccessful, e.g., after reaching a configurable maximum number of MsgA preamble transmissions, and no RAR is decoded, the UE rolls back to the 4-step RACH procedure in the normal UL slot. The UE sets the RA type from 2-step RACH to 4-step RACH and changes its RACH configuration to that configured for normal UL slots. The UE may reset or reinitialize or retain settings for some or all early transmission variables, such as described in other embodiments of the present disclosure. The UE then retries the RA using the normal UL slot according to the 4-step RACH procedure.

In another example, the UE uses a multi-step backoff procedure during RA. For example, the UE first selects a 2-step RACH procedure as an RA type in the XDD slot. The UE then transmits the MsgA preamble one or more times. When the UE determines that the RACH preamble transmission is unsuccessful, e.g., after reaching a configurable maximum number of MsgA preamble transmissions, and no RAR is decoded, the UE rolls back to the 4-step RACH procedure in the XDD slot. The UE sets the RA type from 2-step RACH to 4-step RACH. The UE may reset or reinitialize or retain settings for some or all early transmission variables, such as described in other embodiments of the present disclosure. The UE then retries RA using XDD slots according to the 4-step RACH procedure. When the UE determines that RACH preamble transmission using the 4-step RACH procedure in the XDD slot is still unsuccessful, e.g., after reaching a configurable maximum number of Msg1 preamble transmissions, and no RAR is decoded, the UE rolls back to the 4-step RACH procedure in the normal UL slot. The UE changes its RACH configuration to the RACH configuration configured for the normal UL slot. The UE may reset or reinitialize or retain settings for some or all early transmission variables, such as described in other embodiments of the present disclosure. The UE then retries the RA using the normal UL slot according to the 4-step RACH procedure.

In another example, the UE selects a 2-step RACH procedure as the RA type in the XDD slot. The UE sends the MsgA preamble one or more times. The UE receives the signaling indication and determines that the RACH preamble transmission was successfully received by the gNB. For example, the UE determines the signaling indication by receiving a PDCCH of DCI format 1_0 that includes a CRC scrambled by ra_rnti associated with the time and frequency resources of the PRACH opportunity in which the UE transmitted the PRACH preamble. PDSCH scheduled by DCI format 1_0 indicates fallbackRAR to UE and redirects UE to continue RA in normal UL slots or symbols. The UE then continues its RA transmission using the normal UL slot.

The method 2000 illustrated in fig. 20 describes an example procedure for determining the RA type in an XDD or normal UL slot in accordance with an embodiment of the present disclosure. The UE determines a system configuration indicating whether one of a 2-step RACH ("type 2") or a 4-step RACH ("type 1") is allowed in one of the XDD or normal UL radio resources. The UE selects an RA configuration type from a set of available or allowed RA configuration types. The UE then proceeds with the RA procedure in the RACH resource selection step, conditioned on the selected RA type.

For example, in step 2010, a UE (such as UE 116) determines RACH access types available in an XDD slot. In step 2020, the UE selects one of the RACH access types available in the XDD slot. In step 2030, the UE determines RACH resources according to the RACH access type in the selected XDD slot. In step 2040, the UE transmits a PRACH preamble for the selected RACH access type configuration.

A method 2100, as shown in fig. 21, describes an exemplary backoff procedure from 2-step RACH to 4-step RACH in XDD and normal UL slots, in accordance with embodiments of the present disclosure. The UE determines whether RA transmission using a 2-step RACH ("type 2") procedure in the XDD slot is successful. When unsuccessful, the UE changes the RA configuration type to 4-step RACH and/or time domain resources configured for RA in the normal UL slot. The UE then proceeds with the RA procedure in the RACH resource selection step, conditioned on the selected RA type.

For example, in step 2110, the UE (such as UE 116) determines the available RACH access types and begins transmitting RACH preambles. In step 2120, the UE determines whether the number of RACH preamble transmissions is equal to or greater than preambamoxfd. In response to determining that the number of RACH preamble transmissions is equal to or greater than preambambleTransMaxFD (as determined in step 2120). In step 2130, the UE determines a second RACH access type configured for a normal (such as complete) UL slot. In step 2140, the UE continues the RA procedure in a normal (such as complete) UL slot using the second RACH access type.

One motivation is that the UE first attempts to use a fast 2-step RACH procedure ("type 2") random access using XDD or FD resources in the coverage area of the cell, where the received interference level and UL-DL cross link interference conditions favor FD operation. This is beneficial in greatly reducing control plane setup delay, such as when recovering an RRC connection in the rrc_inactive state for starting DL and UL and transmitting and receiving. PRACH detection by the base station may use the full SIC processing gain at the base station, if possible, depending on signal conditions. A UE that fails RA using configured XDD or FD resources may still benefit from UL coverage and cross-link or no self-interference reception conditions in normal UL slots using a backoff procedure that allows for a seamless transition to 4-step RACH ("type 1") and/or RA resources configured in normal UL slots when necessary.

In certain embodiments, such as those described in fig. 22 below, a UE configured for RA (PRACH preamble transmission) using symbols in an XDD slot uses the adjustment value to determine a size of a reception window for monitoring the PDCCH to detect a DCI format scheduling a PDSCH providing a RAR, as configured by the higher layer parameter RA-response window.

The adjustment value may depend on the number or instance of XDD and complete UL slots over a period of time. After PRACH preamble transmission, a large window size may be configured for UEs configured to use symbol RA in XDD slots. The window size may be provided by a higher layer or may be determined by the UE, for example, to capture the impact of the DL transmission opportunity for Msg2 reduced by using XDD slots and/or BWP settings.

In one example, a value provided by a higher layer for a window size is used, but the/actual length of the indication for monitoring the PDCCH to detect the window scheduling DCI formats for PDSCH reception providing RAR is determined by the UE usage adjustment. The UE transmitting the PRACH preamble in the symbol of the XDD slot determines the adjusted RAR window size in units of milliseconds, or sets of slots to monitor the PDCCH scheduling Msg2, with respect to the corresponding value for the UE transmitting the PRACH preamble only in the full/normal UL slot. The adjustment may be of a fixed size, such as an additional N slots for a plurality of slots, or an additional N milliseconds for the RAR window size, or may depend on parameters for Msg2 reception during a time period, such as the number of XDD/UL slots or symbols in an XDD slot or UL slot.

After PRACH preamble transmission occurs in the symbols of the XDD slot, the adjustment value for monitoring the PDCCH to decode the DCI format of the scheduled RAR may be fixed in the specifications of system operation or may be provided by a higher layer, e.g., according to a list of specified values. Higher layer signaling of adjustment values or indexing of such values may be through RRC or MAC CE. The adjustment value may be an absolute value or an offset value relative to other signaled values. The adjustment value may be applied to an integer or fraction or multiple of a slot or symbol. The size of the export window may be set using a known or configurable SCS. For example, SCS of type 1-PDCCH CSS set defined in NR specification can be used.

For example, the RAR window size (as configured by the higher layer parameter ra-ResponseWindow in the number of slots) for monitoring PDCCH to decode DCI formats scheduled for PDSCH reception with RAR depends on the slot type. If M XDD slots are expected to occur for UL-DL configuration with a period/duration of N slots after PRACH transmission in XDD slot #n, the RAR window size is increased by M slots.

In another example, the parameter ra-ResponseWindow 18 signaled by the second indicates the RAR window size for monitoring the PDCCH to decode DCI formats received by the scheduled PDSCH, while the parameter ra-ResponseWindow signaled by the first indicates the size of the subsequent RAR window for PRACH transmissions in UL slots without FD. For example, the first signaled parameter may be set to a value of 10 milliseconds, while the second signaled parameter is set to 20 milliseconds.

In another example, the RAR window length may depend on transmission parameters of XDD slots or symbols used for PRACH transmission. For example, after PRACH preamble transmission, the RAR window size may be adjusted by a predetermined number of N slots or a set of such values to account for the time offset starting position of PRACH preamble transmission in the symbols of the XDD slot. For example, when FD operation is enabled in a cell, the signaled parameter ra-ResponseWindow increases by a factor of 2, resulting in a window size of 20 milliseconds when a value of 10 milliseconds is signaled.

The motivation for increasing the RAR monitoring window size is to consider the possible loss of DL transmission opportunities in a full duplex system. For example, for a maximum setting of 10 ms for RA-ResponseWindow in a 4-step RA procedure, 17 full DL slots are available in a TDD DDDDDDDSUU configuration with 30kHz SCS. Fewer DL slots per UL-DL configuration period are available for DDSU or DDDSU. In the case of FD enabled in the cell, multiple DL slots may not allow transmission of Msg2 depending on DL and UL initial BWP sizes during initial access and the location of initial BWP. Thus, the increased RAR window size allows the base station to handle the flexibility of the timeline and Msg2 scheduling and avoids unnecessary retransmission of the PRACH preamble of the UE.

As shown in fig. 22, method 2200 describes an example process for determining a RAR window size according to an embodiment of the present disclosure. The UE determines the value of the first parameter ra-ResponseWindow. The UE determines a second parameter value associated with the RAR window size _RAR (value RAR). When the UE determines that adjustment of the RAR window size is needed or requested, the UE determines the RAR window size by combining the first parameter value and the second parameter value to obtain ra-response window and value as _RAR The RAR window size of the sum, either by selecting the larger of the two values, or by selectively applying one of the two values, such as value _RAR Values.

In step 2210, a UE (such as UE 116) determines a value of a parameter ra-ResponseWindow. In step 2220, the UE determines whether more than M DL slots are not available during the DL-UL configuration period. In response to determining that more than M DL slots are not available during the DL-UL configuration period (as determined in step 2220), the UE uses the value in step 2230 _RAR To adjust the RAR window size. In response to determining that M or less DL slots are not available (as determined in step 2220) during the DL-UL configuration period or after adjusting the RAR window size (in step 2230), the UE monitors PDCCH reception of DCI with RA-RNTI in step 2240.

Although fig. 19 illustrates method 1900, fig. 20 illustrates method 2000, fig. 21 illustrates diagram 2100, and fig. 22 illustrates diagram 2200, various changes may be made to fig. 19-22. For example, while the methods are illustrated as a series of steps, the individual steps may overlap, occur in parallel, occur in a different order, or occur multiple times. In another example, steps may be omitted or replaced with other steps. For example, the steps of method 1900 may be performed in a different order.

The above-described flowcharts illustrate example methods that may be implemented in accordance with the principles of the present disclosure, and various changes may be made to the methods illustrated in the flowcharts herein. For example, while shown as a series of steps, individual steps in each figure may overlap, occur in parallel, occur in a different order, or occur multiple times. In another example, steps may be omitted or replaced with other steps.

Fig. 23 shows a block diagram of a terminal (or User Equipment (UE)) according to an embodiment of the present disclosure.

As shown in fig. 23, a terminal according to an embodiment may include a transceiver 2310, a memory 2320, and a controller 2330. The transceiver 2310, the memory 2320 and the controller 2330 of the terminal may operate according to the communication method of the terminal described above. However, the components of the terminal are not limited thereto. For example, the terminal may include more or fewer components than those depicted in fig. 23. In addition, the controller 2330, the transceiver 2310, and the memory 2320 may be implemented as a single chip. In addition, the controller 2330 may include at least one processor.

The transceiver 2310 is collectively referred to as an end station receiver and a terminal transmitter, and may transmit/receive signals to/from a base station or another terminal. The signals transmitted to or received from the terminal may include control information and data. The transceiver 2310 may include an RF transmitter for up-converting and amplifying the frequency of a transmitted signal, and an RF receiver for amplifying the frequency of a low noise and down-converting received signal. However, this is merely an example of transceiver 2310 and the components of transceiver 2310 are not limited to RF transmitters and RF receivers.

In addition, the transceiver 2310 may receive signals through a wireless channel and output signals to the controller 2330, and transmit signals output from the controller 2330 through a wireless channel.

The memory 2320 may store programs and data required for operation of the terminal. In addition, the memory 2320 may store control information or data included in signals obtained by the terminal. The memory 2320 may be a storage medium such as read-only memory (ROM), random-access memory (RAM), hard disk, CD-ROM, and DVD, or a combination of storage media.

The controller 2330 may control a series of processes so that the terminal performs the operations as described above. For example, the controller 2330 may transmit data signals and/or control signals to a base station, and the controller 2330 may receive data signals and/or control signals from a base station.

Fig. 24 shows a block diagram of a base station according to an embodiment of the present disclosure.

As shown in fig. 24, a base station of the present disclosure may include a transceiver 2410, a memory 2420, and a controller 2430. The transceiver 2410, memory 2420 and controller 2430 of a base station may operate according to the communication methods of the base station described above. However, the components of the base station are not limited thereto. For example, the base station may include more or fewer components than depicted in fig. 24. Further, the controller 2430, the transceiver 2410, and the memory 2420 may be implemented as a single chip. Further, the controller 2430 can include at least one processor.

The transceiver 2410 is collectively referred to as a base station receiver and a base station transmitter, and may transmit/receive signals to/from a terminal, another base station, and/or a core network function (or entity). The signals transmitted to or received from the base station may include control information and data. Transceiver 2410 may include an RF transmitter for up-converting and amplifying the frequency of the transmitted signal, and an RF receiver for amplifying the frequency of the low noise and down-converting received signal. However, this is merely an example of transceiver 2410 and components of transceiver 2410 are not limited to RF transmitters and RF receivers.

In addition, the transceiver 2410 may receive and output signals to the controller 2430 through a wireless channel and transmit signals output from the controller 2430 through the wireless channel.

The memory 2420 may store programs and data required for the operation of the base station. Further, the memory 2420 may store control information or data included in a signal obtained by the base station. The memory 2420 may be a storage medium such as ROM, RAM, a hard disk, a CD-ROM, and a DVD, or a combination of storage media.

The controller 2430 may control a series of processes so that the base station performs the operations as described above. For example, the controller 2430 can receive data signals and/or control signals from a terminal, and the controller 2430 can transmit data signals and/or control signals to the terminal.

The methods according to the embodiments described in the claims or the detailed description of the present disclosure may be implemented in hardware, software, or a combination of hardware and software.

When the electrical structure and method are implemented in software, a computer-readable recording medium having one or more programs (software modules) recorded thereon may be provided. One or more programs recorded on the computer-readable recording medium are configured to be executable by one or more processors in the electronic device. The one or more programs include instructions for performing the methods of the embodiments described in the claims or the detailed description of the disclosure.

The program (e.g., software module or software) may be stored in Random Access Memory (RAM), non-volatile memory including flash memory, read Only Memory (ROM), electrically Erasable Programmable Read Only Memory (EEPROM), magnetic disk storage devices, compact disk-ROM (CD-ROM), digital Versatile Disks (DVD), another type of optical storage device, or a magnetic tape cartridge. Alternatively, the program may be stored in a memory system comprising a combination of some or all of the above-described memory devices. Further, each storage device may be included in a plurality of numbers.

The program may also be stored in an attachable storage device that may be accessed over a communication network such as the internet, an intranet, a Local Area Network (LAN), a Wireless LAN (WLAN), or a Storage Area Network (SAN), or a combination thereof. According to embodiments of the present disclosure, a storage device may be connected to an apparatus through an external port. Other storage devices on the communication network may also be connected to an apparatus that performs embodiments of the present disclosure.

In the foregoing embodiments of the present disclosure, elements included in the present disclosure are represented in singular or plural form according to the embodiments. However, for convenience of explanation, singular or plural forms are appropriately selected, and the present disclosure is not limited thereto. Thus, elements expressed in plural may also be configured as a single element, and elements expressed in singular may also be configured as a plurality of elements.

Although the figures show different examples of user equipment, various changes may be made to the figures. For example, the user device may include any number of each component in any suitable arrangement. In general, the drawings are not intended to limit the scope of the disclosure to any particular configuration. Further, while the figures illustrate an operating environment in which the various user device features disclosed in this patent document may be used, these features may be used in any other suitable system.

Although the figures show different examples of user equipment, various changes may be made to the figures. For example, the user device may include any number of each component in any suitable arrangement. In general, the drawings are not intended to limit the scope of the disclosure to any particular configuration. Further, while the figures illustrate an operating environment in which the various user device features disclosed in this patent document may be used, these features may be used in any other suitable system.

Although the present disclosure has been described with exemplary embodiments, various changes and modifications may be suggested to one skilled in the art. The disclosure is intended to embrace such alterations and modifications that fall within the scope of the appended claims. Any description in this application should not be construed as implying that any particular element, step, or function is a essential element which must be included in the scope of the claims. The scope of patented subject matter is defined by the claims.

Claims (15)

1. A method performed by a User Equipment (UE) in a wireless communication system for transmitting a Random Access Channel (RACH) associated with a Random Access (RA) procedure, the method comprising:

and (3) receiving:

first information for a first parameter of a first RACH configuration associated with a first subset of time slots from a set of time slots on a cell,

second information for a second parameter of a second RACH configuration associated with a second subset of time slots from the set of time slots on the cell, and

third information for a condition;

determining whether the condition is valid for transmission in a time slot from the second subset of time slots; and

transmitting RACH in a slot based on a first RACH configuration when the condition is valid, an

When the condition is not valid, RACH is transmitted in a slot based on the second RACH configuration.

2. The method according to claim 1, wherein:

the time slots from the first subset of time slots are not indicated for simultaneous transmission and reception during the same time domain resource on the cell, an

The time slots from the second subset of time slots are indicated for simultaneous transmission and reception during the same time domain resource on the cell.

3. The method according to claim 1, wherein:

The conditions are one of the following:

the value of the maximum counter is set to be the maximum value,

the value of the maximum timer is set to be the maximum timer value,

message reception, or

A signal reception quality value, the signal reception quality value being one of:

reference signal received power level (RSRP), or

Reference Signal Received Quality (RSRQ) value

The conditions are valid in the following cases:

the number of random access attempts is equal to or greater than the maximum counter value,

the duration from the first RACH transmission for the RA procedure is equal to or greater than the maximum timer value,

the message indicating that the condition is valid, or

The value associated with the measurement of the received reference signal is equal to or less than the signal reception quality value.

4. The method of claim 1, further comprising:

resetting the value of a variable associated with the RA procedure based on the second RACH configuration when the condition is valid, and

the value of the variable is used as the value of the first parameter of the first RACH configuration.

5. A User Equipment (UE) in a wireless communication system for transmitting a Random Access Channel (RACH) associated with a Random Access (RA) procedure, the UE comprising:

a transceiver configured to receive:

first information for a first parameter of a first RACH configuration associated with a first subset of time slots from a set of time slots on a cell,

Second information for a second parameter of a second RACH configuration associated with a second subset of time slots from the set of time slots on the cell, and

third information for a condition;

a processor operatively coupled to the transceiver, the processor configured to determine whether the condition is valid for transmission in a time slot from the second subset of time slots,

wherein the transceiver is further configured to:

transmitting RACH in a slot based on a first RACH configuration when the condition is valid, an

When the condition is not valid, RACH is transmitted in a slot based on the second RACH configuration.

6. The UE of claim 5, wherein:

the time slots from the first subset of time slots are not indicated for simultaneous transmission and reception during the same time domain resource on the cell, an

The time slots from the second subset of time slots are indicated for simultaneous transmission and reception during the same time domain resource on the cell.

7. The UE of claim 5, wherein:

the conditions are one of the following:

the value of the maximum counter is set to be the maximum value,

the value of the maximum timer is set to be the maximum timer value,

message reception, or

A signal reception quality value, the signal reception quality value being one of:

reference signal received power level (RSRP), or

Reference Signal Received Quality (RSRQ) value

The conditions are valid in the following cases:

the number of random access attempts is equal to or greater than the maximum counter value,

the duration from the first RACH transmission for the RA procedure is equal to or greater than the maximum timer value,

the message indicating that the condition is valid, or

The value associated with the measurement of the received reference signal is equal to or less than the signal reception quality value.

8. The UE of claim 5, wherein the processor is further configured to:

resetting the value of a variable associated with the RA procedure based on the second RACH configuration when the condition is valid, and

the value of the variable is used as the value of the first parameter of the first RACH configuration.

9. A Base Station (BS) in a wireless communication system, the BS comprising:

a transceiver configured to:

first information for a first parameter of a first Random Access Channel (RACH) configuration associated with a first subset of time slots from a set of time slots on a cell is transmitted,

transmitting second information for a second parameter of a second RACH configuration associated with a second subset of time slots from the set of time slots on the cell,

transmitting third information for the condition

For a Random Access (RA) procedure, when the condition is valid, a RACH is received in a slot based on a first RACH configuration, and

For a Random Access (RA) procedure, when the condition is not valid, a RACH is received in a slot based on a second RACH configuration.

10. The base station of claim 9, wherein:

the time slots from the first subset of time slots are not indicated for simultaneous transmission and reception during the same time domain resource on the cell, an

The time slots from the second subset of time slots are indicated for simultaneous transmission and reception during the same time domain resource on the cell.

11. The base station of claim 9, wherein:

the conditions are one of the following:

the value of the maximum counter is set to be the maximum value,

the value of the maximum timer is set to be the maximum timer value,

message reception, or

A signal reception quality value, the signal reception quality value being one of:

reference signal received power level (RSRP), or

Reference Signal Received Quality (RSRQ) value

The conditions are valid in the following cases:

the number of random access attempts is equal to or greater than the maximum counter value,

the duration from the first RACH transmission for the RA procedure is equal to or greater than the maximum timer value,

the message indicating that the condition is valid, or

The value associated with the measurement of the received reference signal is equal to or less than the signal reception quality value.

12. The BS of claim 9, wherein when the condition is valid, a value of a variable associated with an RA procedure based on the second RACH configuration is reset and used as a value of a first parameter of the first RACH configuration.

13. A method performed by a Base Station (BS) in a wireless communication system, the method comprising:

first information for a first parameter of a first Random Access Channel (RACH) configuration associated with a first subset of time slots from a set of time slots on a cell is transmitted,

transmitting second information for a second parameter of a second RACH configuration associated with a second subset of time slots from the set of time slots on the cell,

transmitting third information for the condition

For a Random Access (RA) procedure, when the condition is valid, a RACH is received in a slot based on a first RACH configuration, and

for a Random Access (RA) procedure, when the condition is not valid, a RACH is received in a slot based on a second RACH configuration.

14. The method according to claim 13, wherein:

the time slots from the first subset of time slots are not indicated for simultaneous transmission and reception during the same time domain resource on the cell, an

The time slots from the second subset of time slots are indicated for simultaneous transmission and reception during the same time domain resource on the cell.

15. The method according to claim 13, wherein:

the conditions are one of the following:

the value of the maximum counter is set to be the maximum value,

the value of the maximum timer is set to be the maximum timer value,

Message reception, or

A signal reception quality value, the signal reception quality value being one of:

reference signal received power level (RSRP), or

Reference Signal Received Quality (RSRQ) value

The conditions are valid in the following cases:

the number of random access attempts is equal to or greater than the maximum counter value,

the duration from the first RACH transmission for the RA procedure is equal to or greater than the maximum timer value,

the message indicating that the condition is valid, or

A value associated with a measurement of the received reference signal is equal to or less than a signal reception quality value, an

Wherein when the condition is valid, the value of the variable associated with the RA procedure based on the second RACH configuration is reset and used as the value of the first parameter of the first RACH configuration.