Probabilistic random access

Abstract

A set of contention-based random access occasions for a base station of a network are generated by a user equipment (UE) of a wireless access network with a random number on an interval. For a generated random number that meets a threshold value within the interval, a random access preamble is transmitted by the UE to the base station within one of the random access occasions of the set. For a generated random number that does not meet the threshold value, contention-based access to the network is attempted by the UE within a subsequent set of random access occasions of the base station, the subsequent set of random access occasions occurring after the set of contention-based random access occasions of the base station.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to Provisional Patent Application No. 63 / 047,617, filed July 2, 2020, entitled “PROBABILISTIC RANDOM ACCES”; and U.S. Patent Application No. 17 / 365,584, filed July 1, 2021, entitled “PROBABILISTIC RANDOM ACCES”, which have been assigned to the assignee of this application and are hereby expressly incorporated herein by reference for all purposes. Technical Field

[0003] In summary, this disclosure relates to communication systems, and more specifically, in some examples, to random access procedures for user equipment in wireless communication access networks. Background Technology

[0004] Wireless communication systems are widely deployed to provide a variety of telecommunications services such as telephone, video, data, messaging, and broadcasting. Typical wireless communication systems employ multiple access technologies capable of supporting communication with multiple users by sharing available system resources. Examples of such multiple access technologies include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, Single Carrier Frequency Division Multiple Access (SC-FDMA) systems, and Time Division Synchronous Code Division Multiple Access (TD-SCDMA) systems. These multiple access technologies have been adopted in various telecommunications standards to provide a common protocol that enables different wireless devices to communicate at the city, national, regional, and even global levels. One example telecommunications standard is 5G New Radio (NR). 5G NR is part of the Continuous Mobile Broadband Evolution program released by the 3rd Generation Partnership Project (3GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., in the case of the Internet of Things (IoT),) and other requirements. 5G NR includes services associated with enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), and ultra-reliable low-latency communications (URLLC). Some aspects of 5G NR can be based on the 4G Long Term Evolution (LTE) standard. There is a need for further improvements to 5G NR technology. These improvements can also be applied to other multiple access technologies and telecommunications standards that employ these technologies. Summary of the Invention

[0005] The following is a simplified overview of one or more aspects to provide a basic understanding of such aspects. This overview is not an exhaustive summary of all anticipated aspects, nor is it intended to identify key or important elements of all aspects, nor to depict the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed descriptions given later.

[0006] The techniques disclosed herein include methods, apparatus, and computer-readable media including instructions for wireless communication. In this technique, a user equipment (UE) of a wireless network generates random numbers at intervals for a contention-based random access opportunity set of a base station of the network. For a generated random number that satisfies a threshold within the interval, the UE sends a random access preamble to the base station within one random access opportunity of the set. For a generated random number that does not satisfy the threshold, the UE attempts contention-based access to the network within a subsequent random access opportunity set of the base station, which occurs after the contention-based random access opportunity set of the base station.

[0007] In some examples of the techniques disclosed herein, the set of random access opportunities is one of the following: a set of {time slot, frequency, beam} tuples; a set of {time slot, frequency} tuples; a set of {time slot, beam} tuples; a set of {frequency, beam} tuples; a set of time slots; or a set of frequencies.

[0008] In some examples, the UE receives a threshold value from the base station before transmission, which is an information element in at least one of a Radio Resource Control message, a Downlink Control Information (DCI) message, a Medium Access Control-Control Element (MAC-CE) message, and a paging message. In some such examples, the threshold value remains valid i) until the threshold value is explicitly changed by the base station, or ii) until a predetermined time period expires.

[0009] In some examples, if i) the generated random number does not meet the threshold or ii) the UE does not obtain access in response to sending a random access preamble, the UE changes the threshold before attempting contention-based access to the network within the base station's subsequent random access opportunity set. In some such examples, the UE increases the threshold. In some such examples, the UE decreases the threshold.

[0010] To achieve the foregoing and related objectives, one or more aspects include the features fully described below and specifically pointed out in the claims. The following description and drawings set forth certain illustrative features of one or more aspects in detail. However, these features indicate only a few of the various ways in which the principles of each aspect may be employed, and this description is intended to include all such aspects and their equivalents. Attached Figure Description

[0011] Figure 1 This is a schematic diagram illustrating an example of a wireless communication system and an access network.

[0012] Figure 2A , 2B Figures 2C and 2D are schematic diagrams illustrating examples of the DL channel within the first 5G / NR frame, the DL channel within the 5G / NR subframe, the UL channel within the second 5G / NR frame, and the UL channel within the 5G / NR subframe, respectively.

[0013] Figure 3 This is a diagram illustrating a base station and user equipment (UE) in an access network according to an example of the technology disclosed herein.

[0014] Figure 4 This is a diagram illustrating a portion of the conceptual 5G NR frame structure used for base stations.

[0015] Figure 5 This is a flowchart illustrating an example of a wireless communication method according to the technology disclosed herein.

[0016] Figure 6 This is a diagram illustrating a portion of a conceptual 5G NR frame structure for a base station, based on an example of the technology disclosed herein.

[0017] Figure 7 This is a diagram illustrating a portion of a conceptual 5G NR frame structure for a base station, based on an example of the technology disclosed herein.

[0018] Figure 8 This is a diagram illustrating a portion of a conceptual 5G NR frame structure for a base station, based on an example of the technology disclosed herein.

[0019] Figure 9 This is a flowchart illustrating an example of a wireless communication method according to the technology disclosed herein.

[0020] Figure 10 This is a flowchart illustrating an example of a wireless communication method according to the technology disclosed herein.

[0021] Figure 11 This is a block diagram of a UE based on an example of the technology disclosed herein. Detailed Implementation

[0022] The detailed description below, taken in conjunction with the accompanying drawings, is intended as a description of various configurations and not as representing only the configurations in which the concepts described herein can be implemented. To provide a thorough understanding of the various concepts, the detailed description includes specific details. However, it will be apparent to those skilled in the art that these concepts can be implemented without these specific details. In some instances, well-known structures and components are shown in block diagram form to avoid obscuring such concepts.

[0023] Use cases already identified for 5G NR include wearable devices, industrial wireless sensors (typically fixed equipment, mMTC use cases), and video surveillance (typically static)—each use case involves a class of devices, sometimes referred to as “RedCap”. Common characteristics of RedCap devices include lower complexity, lower cost, and smaller size. Some RedCap device scenarios exhibit higher potential spatial density and concentrated time requirements for accessing wireless communication infrastructure.

[0024] Specifically, for fixed RedCap devices, the UE distribution within the coverage area of ​​a base station (such as a gNB) may result in some beams of the base station having significantly more UEs requesting access compared to other beams, potentially leading to overload of high-demand beams. In some cases, many RedCap / IoT devices may be best connected to the same cell or beam, and many RedCap / IoT devices may attempt to access the network using a contention-based random access channel (RACH) or physical random access channel procedure (PRACH) within the same random access opportunity. For example, many rentable bicycles or scooters parked in high-demand locations may attempt network access almost simultaneously upon unlocking (e.g., during peak hours). As another example, co-located fixed industrial cameras and sensors may be scheduled to upload data to a server via a wireless communication network at one or more specific times each day. A random access opportunity (RO), or “RACH opportunity”, or “PRACH opportunity” includes a set of resource elements dedicated to random access.

[0025] Methods, non-transitory computer-readable media, and apparatuses are provided in various aspects of this disclosure. In some examples of the techniques disclosed herein, a user equipment (UE) of a wireless network generates random numbers at intervals for a contention-based random access opportunity set of a base station of the network. For a generated random number that satisfies a threshold within the interval, the UE sends a random access preamble to the base station within one random access opportunity of that set. For a generated random number that does not satisfy the threshold, the UE attempts contention-based access to the network within a subsequent random access opportunity set of the base station, which occurs after the contention-based random access opportunity set of the base station.

[0026] In some examples of the techniques disclosed herein, the set of random access opportunities is one of the following: a set of {time slot, frequency, beam} tuples; a set of {time slot, frequency} tuples; a set of {time slot, beam} tuples; a set of {frequency, beam} tuples; a set of time slots; or a set of frequencies.

[0027] In some examples, the UE receives a threshold value from the base station before transmission, which is an information element in at least one of a Radio Resource Control message, a Downlink Control Information (DCI) message, a Medium Access Control-Control Element (MAC-CE) message, and a paging message. In some such examples, the threshold value remains valid i) until the threshold value is explicitly changed by the base station, or ii) until a predetermined time period expires.

[0028] In some examples, if i) the generated random number does not meet the threshold or ii) the UE does not obtain access in response to sending a random access preamble, the UE changes the threshold before attempting contention-based access to the network within the base station's subsequent random access opportunity set. In some such examples, the UE increases the threshold. In some such examples, the UE decreases the threshold.

[0029] To achieve the foregoing and related objectives, one or more aspects include the features fully described below and specifically pointed out in the claims. The following description and drawings set forth certain illustrative features of one or more aspects in detail. However, these features indicate only a few of the various ways in which the principles of each aspect may be employed, and this description is intended to include all such aspects and their equivalents.

[0030] Several aspects of a telecommunications system will now be described with reference to various apparatuses and methods. These apparatuses and methods will be described in detail below and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as “elements”). These elements can be implemented using electronic hardware, computer software, or any combination thereof. Whether these elements are implemented as hardware or software depends on the specific application and the design constraints imposed on the system as a whole. For example, an element, or any part of an element, or any combination of elements, can be implemented as a “processing system” comprising one or more processors. Examples of processors include: microprocessors, microcontrollers, graphics processing units (GPUs), central processing units (CPUs), application processors, digital signal processors (DSPs), reduced instruction set computing (RISC) processors, system-on-a-chip (SoCs), baseband processors, field-programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functions described throughout this disclosure. One or more processors in the processing system can execute software. Whether referred to as software, firmware, middleware, microcode, hardware description language, or other names, software should be broadly interpreted to mean instructions, instruction sets, code, code segments, program code, programs, subroutines, software components, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc.

[0031] Accordingly, in one or more example embodiments, the described functionality can be implemented using hardware, software, or any combination thereof. If implemented in software, the functionality can be stored on or encoded as one or more instructions or code on a computer-readable medium. A computer-readable medium includes a computer storage medium. The storage medium can be any available medium accessible by a computer. By way of example, and not limitation, such a computer-readable medium can include random access memory (RAM), read-only memory (ROM), electrically erasable programmable ROM (EEPROM), optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of computer-readable media of the types described above, or any other medium capable of storing computer-executable code in the form of instructions or data structures accessible by a computer.

[0032] Figure 1This is a schematic diagram illustrating an example of a wireless communication system and access network 100. The wireless communication system (also referred to as a Wireless Wide Area Network (WWAN)) includes a base station 102, a UE 104, an Evolved Packet Core (EPC) 160, and another core network 190 (e.g., a 5G core (5GC)). The base station 102 may include macro cells (high-power cellular base stations) and / or small cells (low-power cellular base stations). Macro cells include base stations. Small cells include femtocells, picocells, and microcells. The base station 102 configured for 4G LTE (collectively referred to as the Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN)) can interface with the EPC 160 via a first backhaul link 132 (e.g., an S1 interface). The base station 102 configured for 5G NR (collectively referred to as the Next Generation RAN (NG-RAN)) can interface with the core network 190 via a second backhaul link 186. In addition to other functions, base station 102 may perform one or more of the following functions: transmission of user data, radio channel encryption and decryption, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection establishment and release, load balancing, distribution of non-access stratum (NAS) messages, NAS node selection, synchronization, radio access network (RAN) sharing, multimedia broadcast multicast service (MBMS), subscriber and device tracking, RAN information management (RIM), paging, location, and transmission of warning messages. Base station 102 may communicate with each other directly or indirectly (e.g., via EPC 160 or core network 190) via a third backhaul link 134 (e.g., X2 interface). The first backhaul link 132, the second backhaul link 186, and the third backhaul link 134 may be wired or wireless.

[0033] Base station 102 can wirelessly communicate with UE 104. Each of base stations 102 can provide communication coverage for a corresponding geographic coverage area 110. Overlapping geographic coverage areas 110 may exist. For example, small cell 102' may have a coverage area 110' that overlaps with the coverage areas 110 of one or more macro base stations 102. A network that includes both small cells and macro cells can be referred to as a heterogeneous network. The heterogeneous network may also include evolved home node B (eNB) (HeNB), which can provide services to restricted groups referred to as closed user groups (CSG). The communication link 120 between base station 102 and UE 104 may include uplink (UL) (also referred to as reverse link) transmission from UE 104 to base station 102 and / or downlink (DL) (also referred to as forward link) transmission from base station 102 to UE 104. The communication link 120 may use multiple-input multiple-output (MIMO) antenna technology, which includes spatial multiplexing, beamforming, and / or transmit diversity. In some examples of the techniques disclosed herein, both the DL and UL between the base station and the UE use the same multi-beam set to transmit / receive physical channels. For example, a given beam set may carry multiple copies of the Physical Downlink Shared Channel (PDSCH) on the DL and multiple copies of multiple Physical Uplink Control Channels (PUCCH) on the UL.

[0034] The communication link can be via one or more carriers. Base station 102 / UE 104 can use a spectrum of up to Y MHz (e.g., 5, 10, 15, 20, 100, 400 MHz, etc.) bandwidth allocated to each carrier in a carrier aggregation for transmission in each direction. Carriers can be adjacent to each other or can be non-adjacent. Carrier allocation can be asymmetric with respect to DL and UL (e.g., more or fewer carriers can be allocated to DL compared to UL). Component carriers can include primary component carriers and one or more secondary component carriers. The primary component carrier can be referred to as the primary cell (PCell), and the secondary component carriers can be referred to as secondary cells (SCells).

[0035] Some UEs 104 may communicate with each other using device-to-device (D2D) communication link 158. D2D communication link 158 may use DL / UL WWAN spectrum. D2D communication link 158 may use one or more sidelink channels, such as Physical Sidelink Broadcast Channel (PSBCH), Physical Sidelink Discovery Channel (PSDCH), Physical Sidelink Shared Channel (PSSCH), and Physical Sidelink Control Channel (PSCCH). D2D communication can be achieved through a variety of wireless D2D communication systems, such as FlashLinQ, WiMedia, Bluetooth, ZigBee, Wi-Fi based on the IEEE 802.11 standard, LTE, or NR. The wireless communication system may also include a Wi-Fi access point (AP) 150, which communicates with a Wi-Fi station (STA) 152 via a communication link 154 in the 5 GHz unlicensed spectrum. When communicating in the unlicensed spectrum, STA 152 / AP 150 may perform a free channel assessment (CCA) before communication to determine if the channel is available. Small cell 102' can operate in licensed and / or unlicensed spectrum. When operating in unlicensed spectrum, small cell 102' can employ NR and use the same 5GHz unlicensed spectrum as the Wi-Fi AP150. Small cell 102' employing NR in unlicensed spectrum can improve coverage of the access network and / or increase the capacity of the access network.

[0036] Base station 102 (whether it is a small cell 102' or a large cell (e.g., a macro base station)) may include and / or be referred to as an eNB, gNodeB (gNB), or another type of base station. Some base stations (such as gNB 180) may operate in one or more frequency bands within the electromagnetic spectrum. Base station 180 and UE 104 may each include multiple antennas (such as antenna elements, antenna panels, and / or antenna arrays) to facilitate beamforming.

[0037] The electromagnetic spectrum is typically subdivided into various categories, bands, channels, etc., based on frequency / wavelength. In 5G NR, the two initial operating bands have been designated as frequency range names FR1 (410MHz-7.125GHz) and FR2 (24.25GHz-52.6GHz). Frequencies between FR1 and FR2 are generally referred to as mid-band frequencies. Although a portion of FR1 is greater than 6GHz, FR1 is often (interchangeably) referred to as the "below 6GHz" band in various documents and articles. Similar naming issues sometimes arise regarding FR2, although it differs from the extremely high frequency (EHF) band (30GHz-300GHz) designated as the "millimeter wave" (mmW) band by the International Telecommunication Union (ITU), FR2 is often (interchangeably) referred to as the "millimeter wave" band in documents and articles.

[0038] Considering the above, unless otherwise specifically stated, it should be understood that when the term "below 6 GHz" is used herein, it can broadly refer to frequencies that are less than 6 GHz, within FR1, or may include intermediate frequency band frequencies. Furthermore, unless otherwise specifically stated, it should be understood that when the term "millimeter wave" is used herein, it can broadly refer to frequencies that may include intermediate frequency band frequencies, within FR2, or within the EHF band. Communication using the mmW radio frequency band has extremely high path loss and short range. The mmW base station 180 can utilize beamforming with UE 104 / 184 to use beam 182 to compensate for path loss and short range.

[0039] Base station 180 may transmit beamforming signals to UE 104 / 184 in one or more transmit directions 182'. UE 104 / 184 may receive beamforming signals from base station 180 in one or more receive directions 182'. UE 104 / 184 may also transmit beamforming signals to base station 180 in one or more transmit directions. Base station 180 may receive beamforming signals from UE 104 in one or more receive directions. Base station 180 / UE 104 / 184 may perform beam training to determine the optimal receive and transmit directions for each of base station 180 / UE 104 / 184. The transmit and receive directions for base station 180 may be the same or different. The transmit and receive directions for UE 104 / 184 may be the same or different.

[0040] EPC 160 may include Mobility Management Entity (MME) 162, other MMEs 164, Serving Gateway 166, Multimedia Broadcast Multicast Service (MBMS) Gateway 168, Broadcast Multicast Service Center (BM-SC) 170, and Packet Data Network (PDN) Gateway 172. MME 162 can communicate with Home Subscriber Server (HSS) 174. MME 162 is the control node that handles signaling between UE 104 and EPC 160. Typically, MME 162 provides bearer and connection management. All user Internet Protocol (IP) packets are transmitted through Serving Gateway 166, which is itself connected to PDN Gateway 172. PDN Gateway 172 provides UE IP address allocation and other functions. PDN Gateway 172 and BM-SC 170 are connected to IP Service 176. IP Service 176 may include the Internet, intranet, IP Multimedia Subsystem (IMS), Packet Switched (PS) streaming service, and / or other IP services. The BM-SC 170 can provide functions for the provisioning and delivery of MBMS user services. The BM-SC 170 can act as an entry point for MBMS transmissions for content providers, authorize and initiate MBMS bearer services within a Public Land Mobile Network (PLMN), and schedule MBMS transmissions. The MBMS gateway 168 can distribute MBMS services to base stations 102 belonging to Multicast-Broadcast Single Frequency Network (MBSFN) areas belonging to broadcast-specific services, and can be responsible for session management (start / stop) and collecting billing information related to eMBMS.

[0041] Core network 190 may include Access and Mobility Management Functions (AMF) 192, other AMFs 193, Session Management Functions (SMF) 194, and User Plane Functions (UPF) 195. AMF 192 may communicate with Unified Data Management (UDM) 196. AMF 192 is the control node that processes signaling between UE 104 and core network 190. Typically, AMF 192 provides QoS streaming and session management. All user Internet Protocol (IP) packets are transmitted via UPF 195. UPF 195 provides UE IP address allocation and other functions. UPF 195 connects to IP service 197. IP service 197 may include the Internet, intranet, IP Multimedia Subsystem (IMS), PS streaming service, and / or other IP services.

[0042] Base stations may also include and / or be referred to as gNB, Node B, eNB, access point, base transceiver, radio base station, radio transceiver, transceiver functional unit, Basic Service Set (BSS), Extended Service Set (ESS), Transmitter Receiver Point (TRP), or some other suitable term. Base station 102 provides UE 104 with access to EPC 160 or core network 190. Examples of UE 104 include cellular phones, smartphones, Session Initiation Protocol (SIP) phones, laptops, personal digital assistants (PDAs), satellite radio units, global positioning systems, multimedia devices, video devices, digital audio players (e.g., MP3 players), cameras, game consoles, tablet devices, smart devices, wearable devices, vehicles, electricity meters, air pumps, large or small kitchen appliances, healthcare devices, implants, sensors / actuators, displays, or any other similarly functional devices. Some UEs in UE 104 may be referred to as IoT devices (e.g., parking meters, air pumps, ovens, vehicles, heart monitors, etc.). UE 104 may also be referred to as a station, mobile station, subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, mobile phone, user agent, mobile client, client, or some other suitable term.

[0043] Continue to refer to Figure 1 In some aspects, UE 104 is configured to generate random numbers over intervals on a contention-based random access opportunity set for base station 102 on a link such as communication link 120. For generated random numbers that satisfy a threshold within the interval, UE 104 sends a random access preamble to base station 102 within one random access opportunity of that set. For generated random numbers that do not satisfy the threshold, UE 104 attempts contention-based access to the network within a subsequent random access opportunity set for base station 102, which occurs after the contention-based random access opportunity set for the base station. UE 104 may use UE probabilistic random access component 142 to perform this generation, transmission, and attempt of subsequent access.

[0044] Although the following description may focus on 5G NR, the concepts described in this article can be applied to other similar areas such as LTE, LTE-A, CDMA, GSM and other wireless technologies.

[0045] Figure 2A This is a schematic diagram 200 showing an example of the first subframe within a 5G / NR frame structure. Figure 2B This is a schematic diagram 230 illustrating an example of a DL channel within a 5G / NR subframe. Figure 2CThis is a schematic diagram 250 showing an example of a second subframe within a 5G / NR frame structure. Figure 2D This is a schematic diagram 280 illustrating an example of a UL channel within a 5G / NR subframe. The 5G / NR frame structure can be Frequency Division Duplex (FDD) (where subframes within a specific set of subcarriers (carrier system bandwidth) are dedicated to either DL or UL), or Time Division Duplex (TDD) (where subframes within a specific set of subcarriers (carrier system bandwidth) are dedicated to both DL and UL). Figure 2A , 2C In the provided example, the 5G / NR frame structure is assumed to be TDD, where subframe 4 is configured with slot format 28 (mostly DL), where D is DL, U is UL, and X is flexibly usable between DL / UL, and subframe 3 is configured with slot format 34 (mostly UL). Although subframes 3 and 4 are shown as having slot formats 34 and 28, respectively, any particular subframe can be configured with any of the various available slot formats 0-61. Slot formats 0 and 1 are full DL and full UL, respectively. Other slot formats 2-61 include a mixture of DL, UL, and flexible symbols. The UE is configured to have a slot format via the received Slot Format Indicator (SFI) (dynamically configured via DL Control Information (DCI) or semi-statically / statically configured via Radio Resource Control (RRC) signaling). It should be noted that the following description also applies to the 5G / NR frame structure as TDD.

[0046] Other wireless communication technologies may have different frame structures and / or different channels. A frame (10 ms) can be divided into 10 equal-sized subframes (1 ms). Each subframe may include one or more time slots. Subframes may also include micro-time slots, which may include 7, 4, or 2 symbols. Each time slot may include 7 or 14 symbols, depending on the time slot configuration. For time slot configuration 0, each time slot may include 14 symbols, while for time slot configuration 1, each time slot may include 7 symbols. Symbols on the DL can be Cyclic Prefix (CP) OFDM (CP-OFDM) symbols. Symbols on the UL can be CP-OFDM symbols (for high-throughput scenarios) or Discrete Fourier Transform (DFT) Spread Spectrum OFDM (DFT-s-OFDM) symbols (also known as Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols) (for power-constrained scenarios; limited to single-stream transmission). The number of time slots within a subframe can be based on the time slot configuration and the numbering scheme. For slot configuration 0, different digital schemes μ0 to μ5 allow 1, 2, 4, 8, 16, and 32 slots per subframe, respectively. For slot configuration 1, different digital schemes 0 to μ2 allow 2, 4, and 8 slots per subframe, respectively. Correspondingly, for slot configuration 0 and digital scheme μ, there are 14 symbols / slot and 2... μ Each time slot / subframe. Subcarrier spacing and symbol length / duration are functions of the digital scheme. Subcarrier spacing can be equal to 2. μ *15kHz, where μ is the digital scheme from 0 to 5. Therefore, digital scheme μ = 0 has a subcarrier spacing of 15kHz, and digital scheme μ = 5 has a subcarrier spacing of 480kHz. The symbol length / duration is negatively correlated with the subcarrier spacing. Figures 2A-2D Examples are provided for slot configuration 0 with 14 symbols per slot and digital scheme μ=2 with 4 slots per subframe. The slot duration is 0.25 ms, the subcarrier spacing is 60 kHz, and the symbol duration is approximately 16.67 μs.

[0047] A resource grid can be used to represent the frame structure. Each time slot includes a resource block (RB) (also known as a physical RB (PRB)), which extends 12 consecutive subcarriers. The resource grid is divided into multiple resource elements (REs). The number of bits carried by each RE depends on the modulation scheme.

[0048] like Figure 2A As shown, some of the REs carry reference (pilot) signals (RS) for the UE. The RS may include a demodulated RS (DM-RS) for channel estimation at the UE (indicated as R for a specific configuration). x(Where 100x is the port number, but other DM-RS configurations are possible) and Channel State Information Reference Signal (CSI-RS). RS may also include Beam Measurement RS (BRS), Beam Refinement RS (BRRS), and Phase Tracking RS (PT-RS). Some examples of the techniques disclosed herein use the DM-RS of the Physical Downlink Control Channel (PDCCH) to assist in channel estimation of the Physical Downlink Shared Channel (PDSCH) (and final demodulation of the user data portion).

[0049] Figure 2B Examples of various DL channels within a subframe of a frame are shown. The Physical Downlink Control Channel (PDCCH) carries the DCI within one or more Control Channel Elements (CCEs), each CCE comprising nine RE Groups (REGs), each REG comprising four consecutive REs in an OFDM symbol. The Primary Synchronization Signal (PSS) may be located within symbol 2 of a specific subframe of the frame. The PSS is used by UE104 to determine subframe / symbol timing and physical layer identification. The Secondary Synchronization Signal (SSS) may be located within symbol 4 of a specific subframe of the frame. The SSS is used by the UE to determine the Physical Layer Cell Identifier Group Number and radio frame timing. Based on the Physical Layer Identifier and Physical Layer Cell Identifier Group Number, the UE can determine the Physical Cell Identifier (PCI). Based on the PCI, the UE can determine the location of the aforementioned DM-RS. The Physical Broadcast Channel (PBCH) (which carries the Master Information Block (MIB)) may logically be grouped with the PSS and SSS to form a Synchronization Signal (SS) / PBCH block. The MIB provides the number of RBs in the system bandwidth and the System Frame Number (SFN). The Physical Downlink Shared Channel (PDSCH) carries user data, broadcast system information (e.g., System Information Block (SIB)) that is not transmitted via the PBCH, and paging messages.

[0050] like Figure 2C As shown, some REs in the REs carry DM-RS for channel estimation at the base station (indicated as R for a specific configuration, but other DM-RS configurations are possible). The UE can transmit DM-RS for the Physical Uplink Control Channel (PUCCH) and DM-RS for the Physical Uplink Shared Channel (PUSCH). The PUSCH DM-RS can be transmitted in the first one or two symbols preceding the PUSCH. In different configurations, the PUCCH DM-RS can be transmitted depending on whether a short or long PUCCH is transmitted and the specific PUCCH format used. The UE can transmit a Sounding Reference Signal (SRS). The SRS can be transmitted in the last symbol of a subframe. The SRS can have a comb structure, and the UE can transmit the SRS on one of the combs. The SRS can be used by the base station for channel quality estimation to enable frequency-dependent scheduling on the UL.

[0051] Figure 2D Examples of various UL channels within a subframe of a frame are shown. The PUCCH can be positioned as indicated in one configuration. The PUCCH carries uplink control information (UCI), such as scheduling requests, channel quality indicators (CQI), precoding matrix indicators (PMI), rank indicators (RI), and hybrid automatic repeat request (HARQ) acknowledgment (ACK) / negative ACK (NACK) feedback. The PUCCH carries data and may also be used to carry buffer status reports (BSR), power headroom reports (PHR), and / or UCI.

[0052] Figure 3 This is a block diagram illustrating communication between base station 310 and UE 350 in the access network. In the DL, IP packets from EPC160 can be provided to controller / processor 375. Controller / processor 375 implements Layer 3 and Layer 2 functions. Layer 3 includes the Radio Resource Control (RRC) layer, and Layer 2 includes the Serving Data Adaptation Protocol (SDAP) layer, Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer, and Media Access Control (MAC) layer. The controller / processor 375 provides: RRC layer functions associated with: broadcasting system information (e.g., MIB, SIB), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-Radio Access Technology (RAT) mobility, and measurement configuration for UE measurement reporting; PDCP layer functions associated with: header compression / decompression, security (encryption, decryption, integrity protection, integrity verification), and handover support functions; RLC layer functions associated with: transmission of upper-layer packet data units (PDUs), error correction via ARQ, concatenation, segmentation and reassembly of RLC service data units (SDUs), resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functions associated with: mapping between logical channels and transport channels, multiplexing of MAC SDUs to transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction via HARQ, priority handling, and logical channel prioritization.

[0053] Transmit (TX) processor 316 and receive (RX) processor 370 implement Layer 1 functions associated with various signal processing functions. Layer 1 (which includes the physical (PHY) layer) may include error detection on the transport channel, forward error correction (FEC) encoding / decoding of the transport channel, interleaving, rate matching, mapping to the physical channel, modulation / demodulation of the physical channel, and MIMO antenna processing. TX processor 316 processes the mapping to the signal constellation diagram based on various modulation schemes (e.g., binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M-phase shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The encoded and modulated symbols can then be split into parallel streams. Each stream can then be mapped to OFDM subcarriers, multiplexed with reference signals (e.g., pilots) in the time and / or frequency domains, and subsequently combined using inverse fast Fourier transform (IFFT) to produce a physical channel carrying a stream of time-domain OFDM symbols. The OFDM stream is spatially precoded to generate multiple spatial streams. Channel estimates from channel estimator 374 can be used to determine coding and modulation schemes, as well as for spatial processing. Channel estimates can be derived based on reference signals transmitted by UE 350 and / or channel condition feedback. Each spatial stream can then be provided to a different antenna 320 via a separate transmitter 318TX. Each transmitter 318TX can utilize the corresponding spatial stream to modulate a radio frequency (RF) carrier for transmission.

[0054] At UE 350, each receiver 354RX receives signals through its respective antenna 352. Each receiver 354RX recovers the information modulated onto the RF carrier and provides this information to the receive (RX) processor 356. The TX processor 368 and RX processor 356 implement Layer 1 functions associated with various signal processing functions. The RX processor 356 can perform spatial processing on this information to recover any spatial stream destined for UE 350. If multiple spatial streams are destined for UE 350, the RX processor 356 can combine them into a single OFDM symbol stream. The RX processor 356 then uses a Fast Fourier Transform (FFT) to transform the OFDM symbol stream from the time domain to the frequency domain. The frequency domain signal includes a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols and reference signals on each subcarrier are recovered and demodulated by determining the most probable signal constellation points transmitted by base station 310. These soft decisions can be based on channel estimates calculated by channel estimator 358. The soft decision is then decoded and deinterleaved to recover the data and control signals originally transmitted by base station 310 on the physical channel. This data and control signals are then provided to controller / processor 359, which implements layer 3 and layer 2 functions.

[0055] The controller / processor 359 may be associated with a memory 360 that stores program code and data. The memory 360 may be referred to as a computer-readable medium. In the UL, the controller / processor 359 provides demultiplexing, packet reassembly, decryption, header decompression, and control signal processing between transport and logical channels to recover IP packets from the EPC 160. The controller / processor 359 is also responsible for error detection to support HARQ operation using ACK and / or NACK protocols.

[0056] Similar to the functions described in the DL transmission performed in conjunction with base station 310, controller / processor 359 provides: RRC layer functions associated with: system information (e.g., MIB, SIB) capture, RRC connection, and measurement reporting; PDCP layer functions associated with: header compression / decompression, and security (encryption, decryption, integrity protection, integrity verification); RLC layer functions associated with: transmission of upper-layer PDUs, error correction via ARQ, concatenation, segmentation and reassembly of RLC SDUs, resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functions associated with: mapping between logical channels and transport channels, multiplexing of MAC SDUs to TBs, demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction via HARQ, priority handling, and logical channel prioritization.

[0057] The TX processor 368 can use the channel estimate derived by the channel estimator 358 based on a reference signal or feedback transmitted by the base station 310 to select an appropriate coding and modulation scheme and facilitate spatial processing. The spatial stream generated by the TX processor 368 can be provided to different antennas 352 via individual transmitters 354TX. Each transmitter 354TX can use the corresponding spatial stream to modulate an RF carrier for transmission.

[0058] At base station 310, UL transmission is processed in a manner similar to that described in conjunction with the receiver function at UE 350. Each receiver 318RX receives signals through its respective antenna 320. Each receiver 318RX recovers the information modulated onto the RF carrier and provides that information to the RX processor 370.

[0059] The controller / processor 375 may be associated with a memory 376 that stores program code and data. The memory 376 may be referred to as a computer-readable medium. In the UL, the controller / processor 375 provides demultiplexing, packet reassembly, decryption, header decompression, and control signal processing between transport and logical channels to recover IP packets from the UE 350. IP packets from the controller / processor 375 can be provided to the EPC 160. The controller / processor 375 is also responsible for error detection to support HARQ operation using ACK and / or NACK protocols.

[0060] Continue to refer to Figure 3 Referring again to the preceding figures for context, in some respects, UE 350 is configured to generate random numbers over intervals on a contention-based random access opportunity set for base station 310 on a link such as communication link 120 (e.g., using one or more of the controller processors 359 that perform the UE probabilistic random access component 142). For a generated random number that satisfies a threshold value within an interval, UE 350 transmits a random access preamble to base station 310 (e.g., using TX processor 368, TX 354, and antenna system 352) within one of the random access opportunities in that set. For a generated random number that does not satisfy the threshold value, UE 350 attempts contention-based access to the network (e.g., via base station 310) within a subsequent random access opportunity set for base station 310. UE 350 may use the UE probabilistic random access component 142 to perform this generation, transmission, and attempt of subsequent access.

[0061] In mathematics, a tuple is a finite, ordered list (sequence) of elements. An n-tuple is a sequence (or ordered list) of n elements, where n is a non-negative integer. Examples include 1-tuples (i.e., a single element), 2-tuples (i.e., a pair), 3-tuples (three elements), 4-tuples (i.e., four elements), 5-tuples (i.e., five elements), and 6-tuples (i.e., six elements). In some aspects, the set of random access opportunities is characterized by one of the following: a set of {timeslot, frequency, beam} tuples (e.g., a set of {timeslot, frequency, beam} 3-tuples) that distributes the set of random access opportunities across time, frequency, and beam; a set of {timeslot, frequency} tuples (e.g., a set of {timeslot, frequency} 2-tuples) that distributes the set of random access opportunities across time and frequency on a single beam; a set of {timeslot, beam} tuples that distributes the set of random access opportunities across multiple timeslots and beams on a single frequency; a set of {frequency, beam} tuples that distributes the set of random access opportunities across frequency and beam in a single timeslot; a set of timeslots that distributes the set of random access opportunities across times on a single {frequency, beam} tuple; and a set of frequencies that distributes the set of random access opportunities across frequencies on a single {timeslot, beam} tuple. In some aspects, UE 350 receives from base station 310 a threshold value as an information element in at least one of radio resource control messages, downlink control information (DCI) messages, media access control-control element (MAC-CE) messages, and paging messages before transmission. In some such examples, the threshold value remains valid i) until the threshold value is explicitly changed by the base station, or ii) until a predetermined time period expires.

[0062] In some examples, if i) the generated random number does not meet the threshold value or ii) UE 350 does not obtain access in response to sending a random access preamble, UE 350 (e.g., using UE probabilistic random access component 142) changes the threshold value before attempting contention-based access to the network within the subsequent random access opportunity set of base station 310. In some such examples, UE 350 increases the threshold value. In some such examples, UE 350 decreases the threshold value.

[0063] Reference Figure 4Continuing with reference to the previous figures for context, a portion of a conceptual 5G NR frame structure 400 for a base station (such as base station 180) is shown. Beams A 182a, B 182b, C 182c, and D 182d are shown to have certain resources allocated for contention-based random access across RACH_slot_0 450 (Beam A 182a, B 182b) and RACH_slot_1 460 (Beam C 182c and D 182d), and then repeat across the same beam 182 with RACH_slot_2. During the normal RACH process, a UE (such as UE 184) receives configuration information broadcast to all UEs within range of base station 180, even those UEs that have not yet been authorized to access the wireless network. The configuration information indicates resource sets (e.g., resource set 402) in which any UE can transmit a random access preamble as part of a contention-based random access procedure. Each of the resources (402a, 402b, 402c, and 402d) is referred to as a “random access opportunity” (RO) or “RACH opportunity” for transmitting the random access preamble. In a normal RACH procedure, UE 184 transmits the random access preamble in any of the four ROs (402a, 402b, 402c, and 402d); this means that the probability of transmission of the random access preamble in resource set 402 of the RO is 100%, and the probability of UE 184 transmitting the random access preamble in any one RO is 25%.

[0064] refer to Figure 5 And continuing with reference to the preceding figures for context, a flowchart of a wireless communication method 500, an example of the technology disclosed herein, is shown. In such a method 500, the UE 184 generates random numbers at intervals for a contention-based set of ROs of a base station 180 of the network (box 510). (Refer to...) Figure 6 And continuing to refer to the previous figures for context, a portion of the conceptual 5G NR frame structure 600 for base station 180 is shown as part of the continued example. In the continued example, the interval is [0, 1]. Figure 6 This shows a set 602 of four contention-based ROs 602a, 602b, 602c, and 602d allocated to BeamA 182a in RACH_slot_0 650, similar to Figure 4The RO set in RACH_slot_0 650 is allocated to BeamB 182b, while BeamC 182c and BeamD 182d are allocated RACH_slot_1 660. When the frame structure begins to repeat beam RACH allocation in RACH slot 2, the RO set for BeamA 182a repeats as set 604 after set 602. The RO set for BeamA 182a remains within the PRACH quasi-co-location (QCL) for BeamA 182a, within ROs 602a, 602b, 602c, and 602d associated with the synchronization signal block (SSB) being used by UE 184. The RO set 602 structure spans time and frequency extensions of ROs 602a, 602b, 602c, and 602d. A contention-based RO set can contain one or more ROs. Note that, as Figure 6 In the example, for a subsequent set that occurs after the set, each RO of the subsequent set is later in time than all ROs of the set.

[0065] Reference Figure 11 And continuing to refer to the previous figures for context, examples of the techniques disclosed herein are shown for use with Figure 3 Another representation of the UE 350 for wireless communication. UE 350 includes a UE probabilistic random access component 142, a controller / processor 359, and a memory 360, as described above. Figure 3 The UE probabilistic random access component 142 includes a generation component 142a. In some examples, the generation component 142a generates random numbers at intervals for a contention-based set of ROs for base stations 180 of the network. Therefore, the generation component 142a can provide a unit for generating random numbers at intervals for a contention-based set of ROs for base stations 180 of the network.

[0066] Refer again Figure 5 For a generated random number that meets a threshold value within an interval, UE 184 sends a random access preamble to base station 180 within one random access opportunity (RO) of that set—box 520 (yes), box 530. In the continuing example, the threshold (q) RO The value is 0.8, and UE 184 generates a random number of 0.45 in the interval [0, 1]. Assume the random number (0.45) is less than or equal to q. RO(0.8) Then UE 184 sends a random access preamble in one of RO 602a, 602b, 602c, or 602d within the set of RO 602. In NR, base station 180 uses SS / PBCH block-to-PRACH(RO) beam association to know which beam 182 UE 184 is using. There can be one SS / PBCH block (also called "SSB") to many ROs or many SS / PCCH blocks to one RO. Association is performed in the frequency domain, then in the time domain within the RACH time slot, and then across the RACH time slot in the time domain. Refer again Figure 6 Each of RO 602a, 602b, 602c and 602d has (1 / 4q) RO There is a 90% chance that UE 184 will use it to send a random access preamble to base station 180 within RO set 602.

[0067] Although in the continuing examples, the generated random number "satisfying the threshold" corresponds to the generated random number being less than or equal to the threshold, other relations can be used, as long as these relations maintain the logic that, for a given set of ROs, the probability that UE 184 will send a random access preamble to base station 180 may be less than 100%. As disclosed herein, this method can be used to extend the random access preamble received at the base station in terms of time, frequency, and space (beam and SSB).

[0068] Refer again Figure 11 Referring again to the previous figures for context, the UE probabilistic random access component 142 includes a transmitting component 142b. In some examples, the transmitting component 142b transmits a random access preamble to the base station 180 within one random access opportunity (RO) of the set, for a random number generated that meets a threshold value within the interval. Therefore, the transmitting component 142b can provide elements for transmitting a random access preamble to the base station 180 within one random access opportunity (RO) of the set, for a random number generated that meets a threshold value within the interval.

[0069] Refer again Figure 5 For random numbers generated that do not meet the threshold value within the interval, UE 184 attempts contention-based random access to base station 180 within the subsequent random access opportunity set—box 520 (no), box 540. See again... Figure 6 In a variation of the continued example, UE 184 generates a random number of 0.9 in the interval [0, 1]. Assume the random number (0.9) is greater than q. RO(0.8) means that UE 184 does not send a random access preamble in one of the ROs (602a, 602b, 602c, 602d) in the set of RO 602, but waits until the next RO set. In the continuing example, the subsequent RO set is set 604 in RACH_slot_2 670, and occurs after the base station's contention-based random access timing set 602.

[0070] Refer again Figure 11 Referring again to the previous figures for context, the UE probabilistic random access component 142 includes an attempt component 142c. In some examples, the attempt component 142c attempts contention-based random access to the base station within a subsequent set of random access opportunities for the base station 180 for a randomly generated number that does not meet a threshold value within an interval. Therefore, the attempt component 142c can provide elements for attempting contention-based random access to the base station within a subsequent set of random access opportunities for the base station 180 for a randomly generated number that does not meet a threshold value within an interval.

[0071] In some respects, the RO set is characterized by one of the following: a set of {timeslot, frequency, beam} tuples distributing random access opportunities across multiple timeslots, frequencies, and beams; a set of {timeslot, frequency} tuples distributing random access opportunities across multiple timeslots and frequencies on a single beam; a set of {timeslot, beam} tuples distributing random access opportunities across multiple timeslots and beams on a single frequency; a set of {frequency, beam} tuples distributing random access opportunities across multiple frequencies and beams in a single timeslot; a set of timeslots distributing random access opportunities across timeslots on a single {frequency, beam} tuple; and a set of frequencies distributing random access opportunities across frequencies on a single {timeslot, beam} tuple.

[0072] Reference Figure 7 And continuing to refer to the previous figures for context, a portion of a conceptual 5G NR frame structure 700 for base station 180 is shown, based on examples of the technology disclosed herein. This RO set 702 in frame structure 700 spans the ROs in the beam-extended RO set 702 at a given frequency: RO 702a / BeamA 182a, RO 702b / BeamB 182b, RO702c / BeamC 182c, and RO 702d / BeamD 182d. The next subsequent RO set 704 begins in RACH_slot_2 670 with RO 704 / BeamA 182a. The probability that any RO in RO set 702 will send a random access preamble is (1 / 4q) RO )x100%.

[0073] Reference Figure 8And continuing to refer to the previous figures for context, a portion of a conceptual 5G NR frame structure 800 for base station 180 is shown, based on examples of the techniques disclosed herein. This RO set 802 in frame structure 800 extends the RO across time, frequency, and space (beam / SSB). Specifically, each RO in RO set 802 is first increased in frequency, then in time, and then in beam across RACH slots. The next subsequent RO set 804 begins in RACH_slot_2 670 with RO 804 / BeamA182a. The probability that any RO in RO set 802 will contain a random access preamble is (1 / 16q). RO )%.

[0074] Reference Figure 9 And continuing to refer to the preceding figures for context, a flowchart of a wireless communication method 900, an example of the technology disclosed herein, is shown. In such a method 900, as combined with... Figure 5 Boxes 510, 520, 530, and 540 are described in detail. In such a method, UE 184 receives from base station 180 a threshold value (box 940) for an information element among at least one of a radio resource control message, a downlink control information (DCI) message, a media access control-control element (MAC-CE) message, and a paging message before transmission.

[0075] For example, q RO The value q can be received by the UE 184 semi-statically (e.g., in RRC) or dynamically (in DCI, MAC-CE, or paging messages), or included in the random access response (MSG.2) in the event of a previous collision. In some aspects, the value q RO It can be changed according to a predefined pattern.

[0076] Refer again Figure 11 Referring again to the preceding figures for context, the UE probabilistic random access component 142 includes a receiving component 142d. In some examples, the receiving component 142d of the UE 184 receives from the base station 180 a threshold value for an information element that is at least one of a Radio Resource Control message, a Downlink Control Information (DCI) message, a Medium Access Control-Control Element (MAC-CE) message, and a paging message before transmission. Therefore, the receiving component 142d can provide a unit for the UE 184 to receive from the base station 180 a threshold value for an information element that is at least one of a Radio Resource Control message, a Downlink Control Information (DCI) message, a Medium Access Control-Control Element (MAC-CE) message, and a paging message before transmission.

[0077] Reference Figure 10And continuing to refer to the preceding figures for context, a flowchart of a wireless communication method 1000, an example of the technology disclosed herein, is shown. In such a method 1000, as combined with... Figure 5 Boxes 510, 520, 530, and 540 are executed as described. In such a method, if i) the generated random number does not meet a threshold value or ii) UE 184 does not obtain access in response to sending a random access preamble, UE 184 changes the threshold value before attempting contention-based access to the network within the subsequent random access opportunity set of base station 180—box 1050 (no) box 1060. This change can be rule-based (embodied in UE 184 or base station 180 / network).

[0078] q RO The value can be configured to change between failed attempts within consecutive RACH slots. For example, if the generated random number is greater than q... RO If, under the given value, no random access preamble is sent after a certain number of configuration attempts, then q RO The value can be set to "1". As another example, if the generated random number is greater than q... RO If, given a value of q, no random access preamble is sent after a certain number of configuration attempts, the UE can incrementally increase q. RO The value of q. As another example, if a random access preamble is sent but a collision occurs (which causes a specific UE 184 to back off and allows other UEs to successfully connect to base station 180 in a contention-based random access process), the UE can incrementally increase q. RO The value of .

[0079] The following examples are merely illustrative and may be combined with, but are not limited to, other embodiments or aspects of the teachings described herein.

[0080] Example 1 is a wireless communication method comprising: a user equipment (UE) of a wireless access network generating random numbers at intervals for a contention-based random access opportunity set of a base station of the network. For a generated random number that satisfies a threshold value within the interval, the UE transmits a random access preamble to the base station within one of the random access opportunities in the set. For a generated random number that does not satisfy the threshold value, the UE attempts contention-based access to the network within a subsequent set of random access opportunities of the base station, the subsequent set of random access opportunities occurring after the contention-based random access opportunity set of the base station.

[0081] In Example 2, the method according to Example 1 further includes: wherein the set of random access opportunities is one of the following: a set of {time slot, frequency, beam} tuples distributed across time, frequency, and beam; a set of {time slot, frequency} tuples distributed across time and frequency on a single beam; a set of {time slot, beam} tuples distributed across multiple time slots and beams on a single frequency; a set of {frequency, beam} tuples distributed across frequency and beam in a single time slot; a set of time slots distributed across time slots on a single {frequency, beam} tuple; and a set of frequencies distributed across frequencies on a single {time slot, beam} tuple.

[0082] In Example 3, the method according to Example 1 or Example 2 further includes: the UE receiving, prior to transmission, the threshold value as an information element of at least one of a Radio Resource Control message, a Downlink Control Information (DCI) message, a Medium Access Control-Control Element (MAC-CE) message, and a paging message from the base station. In Example 4, the method according to any one of Examples 1-3 further includes: wherein the threshold value remains valid i) until the threshold value is explicitly changed by the base station, or ii) until a predetermined time period expires.

[0083] In Example 5, the method according to any one of Examples 1-4 further includes: changing the threshold value before the UE attempts to access the network based on contention within the subsequent random access opportunity set of the base station when i) the generated random number does not satisfy the threshold value or ii) the UE does not obtain access in response to sending the random access preamble. In Example 6, the method according to Example 5 includes: increasing the threshold value. In Example 6, the method according to Example 5 includes: decreasing the threshold value.

[0084] Example 8 includes an apparatus for wireless communication, comprising: a memory; and at least one processor coupled to the memory and configured to perform the method according to any one or more of Examples 1-7. Example 9 includes a computer-readable medium storing computer-executable code that, when executed by a processor, causes the processor to perform the method according to any one or more of claims 1-7. Example 10 includes an apparatus for wireless communication, comprising units for performing the method according to any one or more of claims 1-7.

[0085] The foregoing description is provided to enable any person skilled in the art to implement the various aspects described herein. Various modifications to these aspects will be apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects. Therefore, the claims are not intended to be limited to the aspects shown herein, but are given the full scope consistent with the text claims, wherein reference to the singular form of an element is not intended to mean "one and only one," but rather "one or more," unless expressly stated otherwise. The term "exemplary" as used herein means "serving as an example, instance, or illustration." Any aspect described herein as "exemplary" is not necessarily to be construed as preferred over or superior to other aspects. Unless expressly stated otherwise, the term "some" refers to one or more. Combinations such as "at least one of A, B, or C," "one or more of A, B, or C," "at least one of A, B, and C," "one or more of A, B, and C," and "A, B, C, or any combination thereof" include any combination of A, B, and / or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as "at least one of A, B, or C", "one or more of A, B, or C", "at least one of A, B, and C", "one or more of A, B, and C", and "A, B, C, or any combination thereof" can be A only, B only, C only, A and B, A and C, B and C, or A and B and C, wherein any such combination may contain one or more members of A, B, or C. All structural and functional equivalents of the elements described throughout the various aspects of this disclosure are expressly incorporated herein by reference and intended to be included by the claims, and such structural and functional equivalents are known to or will be known later to those skilled in the art. Furthermore, nothing disclosed herein is intended to be offered to the public, whether or not such disclosure is expressly stated in the claims. The terms "module", "mechanism", "element", "device", etc., may not be a substitute for the term "unit". Therefore, no claim element is to be interpreted as a unit plus a function unless the element is expressly stated using the phrase "unit for...".

Claims

1. A method for wireless communication, comprising: Random numbers are generated at intervals from the set of random access opportunities of the user equipment (UE) of the wireless network to the base station of the wireless network; The UE receives from the base station a threshold value as an information element of at least one of a radio resource control message, a downlink control information (DCI) message, a media access control-control element (MAC-CE) message, and a paging message, wherein the threshold value remains valid i) until the threshold value is explicitly changed by the base station, or ii) until a predetermined time period expires. For a randomly generated number that satisfies the threshold value within the interval, the UE sends a random access preamble to the base station within one random access opportunity of the random access opportunity set; and For any random number generated that does not meet the threshold value, the UE attempts to access the wireless network based on contention within the subsequent random access opportunity set of the base station, the subsequent random access opportunity set occurring after the random access opportunity set of the base station.

2. The method according to claim 1, wherein, The set of random access opportunities is one of the following: The set of {time slot, frequency, beam} tuples, which distributes the set of random access opportunities across time, frequency, and beam; The set of {time slot, frequency} tuples, distributed across time and frequency on a single beam, represents the set of random access opportunities. The set of {time slot, beam} tuples, which distributes the set of random access opportunities across multiple time slots and beams on a single frequency; The set of {frequency, beam} tuples, which distributes the set of random access opportunities across frequency and beam in a single time slot; The time slot set is the set of random access opportunities distributed across time slots on a single {frequency, beam} tuple; as well as The frequency set is the set of random access opportunities distributed across frequencies on a single {time slot, beam} tuple.

3. The method according to claim 1, further comprising: If i) the generated random number does not meet the threshold value or ii) the UE does not obtain access in response to sending the random access preamble, the following operations are performed: The threshold value is changed by the UE before attempting contention-based access to the wireless network within the subsequent random access opportunity set of the base station.

4. The method according to claim 3, further comprising: If the generated random number does not meet the threshold value, the threshold value is increased.

5. The method according to claim 3, further comprising: When the UE does not obtain access in response to sending the random access preamble, the threshold value is reduced.

6. A user equipment (UE) for wireless communication, comprising: Memory; as well as At least one processor is coupled to the memory, the memory including instructions executable by the at least one processor to cause the UE to perform the following operations: For the random access opportunity set of the base station of the wireless network, random numbers are generated at intervals; The base station receives a threshold value as an information element of at least one of a radio resource control message, a downlink control information (DCI) message, a media access control-control element (MAC-CE) message, and a paging message, wherein the threshold value remains valid i) until the threshold value is explicitly changed by the base station, or ii) until a predetermined time period expires. For a randomly generated number that satisfies the threshold value within the interval, a random access preamble is sent to the base station within one random access opportunity of the random access opportunity set; and For any generated random number that does not meet the threshold value, a contention-based access attempt is made to the wireless network within a subsequent random access opportunity set of the base station, which occurs after the random access opportunity set of the base station.

7. The user equipment according to claim 6, wherein, The set of random access opportunities is one of the following: The set of {time slot, frequency, beam} tuples, which distributes the set of random access opportunities across time, frequency, and beam; The set of {time slot, frequency} tuples, distributed across time and frequency on a single beam, represents the set of random access opportunities. The set of {time slot, beam} tuples, which distributes the set of random access opportunities across multiple time slots and beams on a single frequency; The set of {frequency, beam} tuples, which distributes the set of random access opportunities across frequency and beam in a single time slot; The time slot set is the set of random access opportunities distributed across time slots on a single {frequency, beam} tuple; as well as The frequency set is the set of random access opportunities distributed across frequencies on a single {time slot, beam} tuple.

8. The user equipment according to claim 6, wherein, The memory further includes instructions executable by the at least one processor to cause the UE to perform the following operations when i) the generated random number does not meet the threshold value or ii) the UE does not obtain access in response to sending the random access preamble: The threshold value is changed before attempting contention-based access to the wireless network within the subsequent random access opportunity set of the base station.

9. The user equipment according to claim 8, wherein, The memory also includes instructions executable by the at least one processor to cause the UE to perform the following operation: increase the threshold value when the generated random number does not meet the threshold value.

10. The user equipment according to claim 8, wherein, The memory also includes instructions executable by the at least one processor to cause the UE to decrease the threshold value when the UE does not obtain access in response to sending the random access preamble.

11. A non-transitory computer-readable medium storing computer-executable code, said code, when executed by a processor, causing the processor to perform the following operations: For the random access opportunity set of the base station of the wireless network, random numbers are generated at intervals; The threshold value received from the base station as an information element in at least one of radio resource control messages, downlink control information (DCI) messages, medium access control-control element (MAC-CE) messages, and paging messages, wherein, The threshold value remains valid i) until the threshold value is explicitly changed by the base station, or ii) until the predetermined time period expires; For a random number generated that satisfies the threshold value within the interval, a random access preamble is sent to the base station within one of the random access opportunities in the set of random access opportunities. as well as For any generated random number that does not meet the threshold value, a contention-based access attempt is made to the wireless network within a subsequent random access opportunity set of the base station, which occurs after the random access opportunity set of the base station.

12. The non-transitory computer-readable medium according to claim 11, wherein, The set of random access opportunities is one of the following: The set of {time slot, frequency, beam} tuples, which distributes the set of random access opportunities across time, frequency, and beam; The set of {time slot, frequency} tuples, distributed across time and frequency on a single beam, represents the set of random access opportunities. The set of {time slot, beam} tuples, which distributes the set of random access opportunities across multiple time slots and beams on a single frequency; The set of {frequency, beam} tuples, which distributes the set of random access opportunities across frequency and beam in a single time slot; The time slot set is the set of random access opportunities distributed across time slots on a single {frequency, beam} tuple; as well as The frequency set is the set of random access opportunities distributed across frequencies on a single {time slot, beam} tuple.

13. The non-transitory computer-readable medium of claim 11, further storing computer-executable code that, when executed by the processor, causes the processor to perform the following operations: when i) the generated random number does not satisfy the threshold value or ii) the processor's device does not obtain access in response to sending the random access preamble, the processor performs the following operations: The threshold value is changed before attempting contention-based access to the wireless network within the subsequent random access opportunity set of the base station.

14. The non-transitory computer-readable medium of claim 13, further storing computer-executable code that, when executed by the processor, causes the processor to: increase the threshold value when the generated random number does not satisfy the threshold value.

15. The non-transitory computer-readable medium of claim 13, further storing computer-executable code that, when executed by the processor, causes the processor to: decrease the threshold value when the device does not obtain access in response to sending the random access preamble.

16. An apparatus for wireless communication, comprising: A unit used to generate random numbers at intervals for the set of random access opportunities for base stations of wireless networks; A unit for receiving from the base station a threshold value as an information element of at least one of a radio resource control message, a downlink control information (DCI) message, a media access control-control element (MAC-CE) message, and a paging message, wherein the threshold value remains valid i) until the threshold value is explicitly changed by the base station, or ii) until a predetermined time period expires. A unit for transmitting a random access preamble to the base station within a random access opportunity of the random access opportunity set, based on a random number generated that satisfies the threshold value within the interval; and A unit for attempting contention-based access to the wireless network within a subsequent set of random access opportunities of the base station for a generated random number that does not meet the threshold value, the subsequent set of random access opportunities occurring after the random access opportunity set of the base station.

17. The apparatus according to claim 16, wherein, The set of random access opportunities is characterized by one of the following: The set of {time slot, frequency, beam} tuples is distributed across multiple time slots, frequencies, and beams to represent the set of random access opportunities; The set of {time slot, frequency} tuples is distributed across multiple time slots and frequencies on a single beam to represent the set of random access opportunities. The set of {time slot, beam} tuples, which distributes the set of random access opportunities across multiple time slots and beams on a single frequency; The set of {frequency, beam} tuples, which distributes the set of random access opportunities across multiple frequencies and beams in a single time slot; The time slot set is the set of random access opportunities distributed across time slots on a single {frequency, beam} tuple; as well as The frequency set is the set of random access opportunities distributed across frequencies on a single {time slot, beam} tuple.

18. The apparatus of claim 16, further comprising: A unit for changing the threshold value before attempting contention-based access to the wireless network within the subsequent random access opportunity set of the base station when i) the generated random number does not meet the threshold value or ii) the device fails to obtain access in response to sending the random access preamble.

19. The apparatus of claim 18, further comprising: A unit for increasing the threshold value when the generated random number does not meet the threshold value.

20. The apparatus of claim 18, further comprising: A unit for reducing the threshold value when the device does not obtain access in response to sending the random access preamble.

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