RU2774872C2 - Procedure of prioritized random access - Google Patents

Abstract

FIELD: wireless communication.

SUBSTANCE: base station configures user equipment with parameters of transmission delay adjustment for one or more priority levels for random access requests, receives from user equipment a random access request and transmits to user equipment a response to the random access request, including a base transmission delay interval, to modify a transmission delay interval in user equipment based on priority of the random access request.

EFFECT: increase in the flexibility of processing events of prioritized random access.

28 cl, 12 dwg

Description

Cross-reference to related applications

[0001] This application claims priority of U.S. Application No. 16/105,750, filed August 20, 2018, which claims priority of U.S. Provisional Application No. 62/548,291, filed August 21, 2017, entitled “Prioritized Random Access Procedure” and assigned to the assignee of this application, contents which are incorporated herein by reference in their entirety.

disclosure area

[0002] Aspects of the present invention relate to wireless communications, more specifically to prioritized random access in wireless communication systems.

Description of the prior art

[0003] Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Exemplary wireless communication systems may use multiple access technologies capable of communicating with multiple users by sharing available system resources (eg, bandwidth, transmit power). 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) and Synchronous Time Division Code Division Multiple Access (TD-SCDMA) systems.

[0004] In some examples, a multiple access wireless communication system may include a number of base stations, each of which simultaneously communicates with multiple communication devices, otherwise known as user equipments (UEs). In a Long Term Evolution (LTE) or LTE Evolved (LTE-A) network, a set of one or more base stations may define an eNodeB (eNB). In other examples (e.g., in a next generation or 5G network), a multiple access wireless communication system may include a number of distributed units (DUs) (e.g., edge units (EU), edge nodes (EN), radio heads (RH), smart radio heads (SRHs), transmit-receive points (TRPs), etc.) in communication with a number of central units (CUs) (e.g. central nodes (CNs), access node controllers (ANCs), etc.). ), where a set of one or more distributed units, in communication with a central unit, may define an access node (e.g., new radio base station (NR BS), new radio node-B (NR NB), network node, 5G NB, gNB , gNodeB etc.). A base station or DU may communicate with a set of UEs on downlink channels (eg, for transmissions from a base station or to a UE) and uplink channels (eg, for transmissions from a UE to a base station or distributed unit).

[0005] These multiple access technologies have been adopted in various telecommunications standards to provide a common protocol that allows various wireless devices to communicate at a municipal, national, regional, and even global level. An example of a new telecommunications standard is the new radio (NR), such as 5G radio access. NR is a set of extensions to the LTE mobile communication standard promulgated by the 3rd Generation Partnership Project (3GPP). It is designed to better support mobile broadband Internet access by improving spectrum efficiency, reducing costs, improving services, utilizing new spectrum, and better integrating with other open standards using Cyclic Prefix (CP) OFDMA in the downlink (DL) and in the uplink (UL), as well as support for beamforming, multiple input/multiple output (MIMO) antenna technology, and carrier aggregation.

[0006] However, as the demand for mobile broadband access continues to increase, there is a need for further improvements in NR technology. Preferably, these improvements should be applicable to other multiple access technologies and telecommunications standards that use these technologies.

BRIEF DESCRIPTION OF THE INVENTION

[0007] As described herein, some wireless systems may use directional beams for transmission and reception.

[0008] Some aspects of the present disclosure provide a method for wireless communication, which can be performed by, for example, a base station (BS). The method typically includes receiving, from a user equipment (UE), a random access request including information identifying the type of random access event to be triggered, identifying one or more backoff adjustment parameters (backoff) associated with a backoff interval. to be observed at the user equipment based at least in part on the priority associated with the random access event type, and transmitting, to the user equipment, a random access response including the identified one or more backoff adjustment parameters.

[0009] Some aspects of the present disclosure provide a method for wireless communication, which can be performed by, for example, a UE. The method typically includes transmitting, to a base station, a random access request, receiving, from the base station, a random access response including one or more backoff adjustment parameters, and based on one or more backoff adjustment parameters and a priority associated with the random access request type, determining a backoff interval specifying the amount of time to wait before retransmitting the random access request.

[0010] Some aspects of the present disclosure provide a method for wireless communication, which may be performed by, for example, a base station (BS). The method typically includes transmitting, to a user equipment (UE), configuration information comprising one or more backoff adjustment scaling factors, each backlog adjustment scaling factor being associated with a different random access priority level, receiving from the UE, a request random access including information identifying the type of random access event being triggered, and transmitting, to the UE, a random access response including a backoff parameter used in conjunction with one or more backoff adjustment scaling factors to calculate backoff period.

[0011] Some aspects of the present disclosure provide a method for wireless communication, which can be performed by, for example, a user equipment (UE). The method typically includes receiving, from a base station (BS), configuration information comprising one or more backoff adjustment scaling factors, each backoff adjustment scaling factor associated with a different random access priority level, transmitting, to the BS, a random access request, receiving, from the BS, a random access response including a backoff parameter, calculating a backoff period based on the backoff parameter and one or more backoff correction scaling factors, and retransmitting the random access request after the calculated backoff period has elapsed transmission.

[0012] Aspects typically include methods, apparatuses, systems, computer-readable media, and processing systems as generally described herein with reference to and as illustrated in the accompanying drawings.

[0013] Other aspects, features, and embodiments of the present invention will become apparent to those skilled in the art upon consideration of the following description of specific exemplary embodiments of the present invention in conjunction with the accompanying drawings. Although features of the present invention may be discussed below with respect to certain embodiments and drawings, all embodiments of the present invention may include one or more of the preferred features discussed herein. In other words, although one or more embodiments may be discussed as having some preferred features, one or more of such features may also be used in accordance with the various embodiments of the invention discussed herein. Likewise, while exemplary embodiments may be discussed below as apparatus, system, or method embodiments, it should be understood that such exemplary embodiments may be implemented in various devices, systems, and methods.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG. 1 is a block diagram conceptually illustrating an exemplary telecommunications system, in accordance with some aspects of the present disclosure.

[0015] FIG. 2 is a block diagram illustrating an example distributed RAN logical architecture, in accordance with some aspects of the present disclosure.

[0016] FIG. 3 is a schematic diagram illustrating an exemplary distributed RAN physical architecture, in accordance with some aspects of the present disclosure.

[0017] FIG. 4 is a block diagram conceptually illustrating the structure of an exemplary BS and UE, in accordance with some aspects of the present disclosure.

[0018] FIG. 5 is a diagram showing examples for implementing a communications protocol stack, in accordance with some aspects of the present disclosure.

[0019] FIG. 6 illustrates an example frame format for a new radio (NR) system, in accordance with some aspects of the present disclosure.

[0020] FIG. 7 illustrates an exemplary operation performed by a base station (BS) to perform prioritized random access, in accordance with some aspects of the present disclosure.

[0021] FIG. 8 illustrates an exemplary operation performed by a UE) to perform prioritized random access, in accordance with some aspects of the present disclosure.

[0022] FIG. 9 illustrates an exemplary operation performed by a base station (BS) to configure a user equipment (UE) for prioritized random access, in accordance with some aspects of the present disclosure.

[0023] FIG. 10 illustrates an exemplary operation performed by a user equipment (UE) to perform prioritized random access, in accordance with some aspects of the present disclosure.

[0024] In FIG. 11 is a message flow diagram illustrating messages exchanged between a base station and user equipment to perform prioritized random access, in accordance with some aspects of the present disclosure.

[0025] FIG. 12 illustrates a communications device that may include various components configured to perform operations for the methods disclosed herein, in accordance with aspects of the present disclosure.

[0026] To facilitate understanding, the same reference numbers have been used, where possible, to refer to the same elements that are common in the drawings. It is contemplated that elements disclosed in one aspect may be used with advantage in other aspects without specific reference to it.

DETAILED DESCRIPTION

[0027] The following description provides examples and does not limit the scope, applicability or examples set forth in the claims. Changes may be made to the operation and arrangement of the elements discussed without departing from the scope of this disclosure. Various examples may omit, replace, or add various procedures or components, as needed. For example, the methods described may be performed in a different order from that described, and various steps may be added, omitted, or combined. In addition, functions described with reference to some examples may be combined in some other examples. For example, an apparatus may be implemented, or a method may be implemented using any number of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method that is practiced using a different structure, functionality, or structure and functionality in addition to or otherwise than the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure described herein may be embodied by one or more elements of a claim. The word "illustrative" is used here to mean "serving as an example, instance or illustration". Any aspect described herein as "exemplary" is not necessarily to be construed as preferable or advantageous over other aspects.

[0028] The methods described in this application can be used for various wireless communication technologies such as LTE, CDMA, TDMA, FDMA, OFDMA, SC-FDMA and other networks. The terms "network" and "system" are often used interchangeably. A CDMA network may implement a radio technology such as Universal Terrestrial Radio Access (UTRA), cdma2000, and so on. UTRA includes Wideband CDMA (WCDMA) and other CDMA variants. cdma2000 covers IS-2000, IS-95 and IS-856 standards. A TDMA network may implement a radio technology such as Global System for Mobile Communications (GSM). OFDMA network can implement radio technology such as NR (such as 5G RA), Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDMA, etc. UTRA and E-UTRA are part of the Universal Mobile Telecommunications System (UMTS).

[0029] New Radio (NR) is a new wireless communication technology under development along with the 5G Technology Forum (5GTF). 3GPP Long Term Evolution (LTE) and LTE Evolved (LTE-A) are UMTS releases that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents from an organization called the 3rd Generation Partnership Project (3GPP). cdma2000 and UMB are described in documents from an organization called 3rd Generation Partnership Project 2 (3GPP2). The methods described in this document can be used for the wireless networks and radio technologies mentioned above, as well as other wireless networks and radio technologies. For clarity, while aspects may be described herein using terminology commonly associated with 3G and/or 4G wireless technologies, aspects of the present disclosure may be applied to other generations of communication systems such as 5G and beyond, including NR technologies.

[0030] NR can support various wireless services such as Enhanced Mobile Broadband (eMBB) oriented to wide bandwidth (e.g. above 80 MHz), millimeter wave (mmW) oriented to high carrier frequency (e.g. 60 GHz ), Massive MTC (mMTC) oriented towards MTS methods without backwards compatibility, and/or task-critical communication oriented towards ultra-reliable low latency communication (URLLC). These services may include latency and reliability requirements. These services may also have different transmission time intervals (TTIs) to meet the respective quality of service (QoS) requirements. In addition, these services may coexist in the same subframe.

[0031] Some multipath wireless systems, such as mmW systems, provide gigabit speeds over cellular networks due to the availability of large amounts of bandwidth. However, the unique high path loss problems faced by millimeter wave systems require new techniques such as hybrid beamforming (analogue and digital), which are not available in 3G and 4G systems. Hybrid beamforming can increase the link budget/signal-to-noise ratio (SNR) that can be used in the RACH.

[0032] In such systems, a node B (NB) and a user equipment (UE) may communicate on active beamformed transmission beams. In order for beamforming (beamforming) to function correctly, the NB may need to monitor the beams using beam measurements performed (eg, based on reference signals transmitted by the NB) and feedback generated at the UE. However, since the direction of the reference signal is unknown at the UE, the UE may need to evaluate multiple beams to obtain the best Rx beam for a given NB Tx beam. Accordingly, if the UE must sweep all of its Rx beams to perform measurements (eg, to determine the best Rx beam for a given NB Tx beam), then the UE may experience significant measurement delays and impact on battery life. In addition, the need to sweep all Rx paths results in resource inefficiency. Thus, aspects of the present disclosure provide methods for assisting a UE in making serving and neighbor cell measurements using Rx beamforming.

EXAMPLE WIRELESS COMMUNICATION SYSTEM

[0033] FIG. 1 illustrates an exemplary wireless network 100 in which aspects of the present disclosure may be performed. According to an example, the wireless network may be an NR or 5G network that can support mmW communication. mmW communication relies on beamforming to satisfy link margin. mmW communications may use directional beamforming so that signaling is directional. Accordingly, the transmitter may focus the transmission energy in some narrow direction (eg, the beams may have a narrow angle), as shown in FIG. 8. The receiving entity may use beamforming at the receiver to receive the transmitted signaling.

[0034] In order to more efficiently use resources and conserve power when communicating using beamforming, UE 120 may be configured to perform operations 900 and the methods described herein to beamform a UE receiver. BS 110 may include a transmit-receive point (TRP), a Node B (NB), a 5G NB, an access point (AP), an NR (new radio) BS, a master BS, a primary BS, and so on. NR network 100 may include a central unit.

[0035] As shown in FIG. 1, wireless network 100 may include a number of base stations 110 and other network entities. According to one example, network entities, including BSs and UEs, can communicate at high frequencies (eg > 6 GHz) using beams.

[0036] The BS may be a station that communicates with the UE. Each BS 110 may provide communication coverage for a specific geographic area. In 3GPP, the term “cell” may refer to the coverage area of a Node B (Node B) and/or the Node B subsystem serving that coverage area, depending on the context in which the term is used. In NR systems, the term “cell” and gNB, Node B, 5G NB, AP, NR BS, NR BS, or TRP may be used interchangeably. In some examples, the cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of the mobile base station. In some examples, base stations may be interconnected with each other and/or with one or more other base stations or network nodes (not shown) in wireless network 100 via various types of transport network interfaces such as direct physical connection, virtual network, or volume. similar using any suitable transport network.

[0037] Typically, any number of wireless networks can be deployed in a given geographic area. Each wireless network may support a specific radio access technology (RAT) and may operate on one or more frequencies. RAT may also be referred to as radio technology, air interface, etc. A frequency may also be referred to as a carrier, a frequency channel, and so on. Each frequency can support one RAT in a given geographic area to avoid mutual interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed.

[0038] The BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or other types of cells. A macro cell may cover a relatively large geographic area (eg, several kilometers in radius) and may allow unrestricted access by a UE with a service subscription. A pico cell may cover a relatively small geographic area and may allow unrestricted access by a UE with a service subscription. A femtocell may cover a relatively small geographic area (eg, at home) and may allow limited access to UEs associated with a femtocell (eg, UEs in a Closed Dialogue Group (CSG), UEs for users in a home, etc.). A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In the example shown in FIG. 1, BSs 110a, 110b, and 110c may be macro BSs for macro cells 102a, 102b, and 102c, respectively. BS 110x may be a pico BS for pico cell 102x. BSs 110y and 110c may be femto BSs for femtocells 102y and 102z, respectively. The BS may support one or more (eg, three) cells.

[0039] Wireless network 100 may also include relay stations. A relay station is a station that receives a transmission of data and/or other information from a previous station (eg, BS or UE) and sends the transmission of data and/or other information to a subsequent station (eg, UE or BS). The relay station may also be a UE that relays transmissions for other UEs. In the example shown in FIG. 1, relay station 110r may communicate with BS 110a and UE 120r to facilitate communication between BS 110a and UE 120r. A relay station may also be referred to as a BS relay, a repeater, and so on.

[0040] The wireless network 100 may be a heterogeneous network that includes various types of BSs, such as macro BSs, pico BSs, femto BSs, repeaters, and so on. These different types of BSs may have different transmit power levels, different coverage areas, and different effects on interference in the wireless network 100. BSs and repeaters may have a lower transmit power level (eg, 1 watt).

[0041] Wireless network 100 may support synchronous or asynchronous operation. For synchronous operation, BSs may have similar frame timing, and transmissions from different BSs may be approximately aligned in time. For an asynchronous operation, BSs may have different frame timings, and transmissions from different BSs may not be time aligned. The methods described in this document can be used for both synchronous and asynchronous operation.

[0042] Network controller 130 may communicate with a set of BSs and provide coordination and control for those BSs. Network controller 130 may communicate with BS 110 via a transport network. BS 110 may also communicate with each other, for example, directly or indirectly, via a wireless or wired transport network.

[0043] UEs 120 (eg, 120x, 120y, etc.) may be dispersed throughout wireless network 100, and each UE may be fixed or mobile. A UE may also be referred to as a mobile station, a terminal, an access terminal, a subscriber unit, a station, a customer premises equipment (CPE), a cellular phone, a smartphone, a personal digital assistant (PDA), a wireless modem, a wireless communication device, a portable device, a laptop computer , cordless phone, wireless local loop station (WLL), tablet, camera, gaming device, netbook, smartbook, ultrabook, medical device or medical equipment, biometric sensor/device, wearable device such as smart watch, smart wear, smart glasses, smart bracelet, smart jewelry (such as a smart ring, smart bracelet, etc.), an entertainment device (such as a music device, video device, satellite radio, etc.), an automotive component, or sensor, smart meter/sensor, industrial manufacturing equipment, global positioning system device, or any other suitable device that is configured, to communicate via a wireless or wired medium. Some UEs may be referred to as evolved or machine type communication devices (MTC) or evolved MTC devices (eMTC). MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, counters, monitors, location tags, etc. that can communicate with a BS, another device (for example, a remote device), or some other entity. . A wireless node may provide, for example, connectivity to or to a network (eg, a wide area network such as the Internet or a cellular network) via a wired or wireless link. Some UEs may be considered as Internet of Things (IoT) devices.

[0044] FIG. 1, a solid line with double arrows indicates desired transmissions between a UE and a serving BS, which is a BS intended to serve the UE on the downlink and/or uplink. The dotted line with double arrows indicates interfering transmissions between the UE and the BS.

[0045] Some wireless networks (eg, LTE) use orthogonal frequency division multiplexing (OFDM) in the downlink and single carrier frequency division multiplexing (SC-FDM) in the uplink. OFDM and SC-FDM partition the system bandwidth into multiple (K) orthogonal subcarriers, which are also commonly referred to as tones, bins, and so on. Each subcarrier may be modulated with data. Typically, modulation symbols are sent in the frequency domain with OFDM and in the time domain with SC-FDM. The spacing (spacing) between adjacent subcarriers may be fixed and the total number of subcarriers (K) may be dependent on the system bandwidth. For example, the subcarrier spacing may be 15 kHz, and the minimum resource allocation (so-called “resource block”) may be 12 subcarriers (or 180 kHz). Therefore, the nominal FFT size can be 128, 256, 512, 1024, or 2048 for a system bandwidth of 1.25, 2.5, 5, 10, or 20 megahertz (MHz), respectively. The system bandwidth may also be divided into subbands. For example, a subband may span 1.08 MHz (e.g., 6 resource blocks) and there may be 1, 2, 4, 8, or 16 subbands for a system bandwidth of 1.25, 2.5, 5, 10, or 20 MHz, respectively. .

[0046] While aspects of the examples described herein may be associated with LTE technologies, aspects of the present disclosure may be applicable in other wireless communication systems such as NR.

[0047] The NR may use OFDM with CPs in the uplink and downlink, and include support for half-duplex operation using TDD. A single component carrier bandwidth of 100 MHz can be supported. NR resource blocks may span 12 subcarriers with a subcarrier bandwidth of 75 kHz over a duration of 0.1 ms. In one aspect, each radio frame may consist of 50 10 ms subframes. Therefore, each subframe may be 0.2 ms long. In another aspect, each radio frame may consist of 10 10 ms subframes, where each subframe may be 1 ms in length. Each subframe may indicate a link direction (ie, DL or UL) for data transmission, and the link direction for each subframe may be dynamically switched. Each subframe may include DL/UL data as well as DL/UL control data. The UL and DL subframes for NR may be as described in more detail below with reference to FIG. 6 and 7. Beamforming may be supported and the beam direction may be dynamically configured. MIMO transmissions with precoding may also be supported. MIMO configurations in DL can support up to 8 transmit antennas with DL multilayer transmissions up to 8 streams and up to 2 streams per UE. Multilayer transmissions of up to 2 streams per UE may be supported. Multi-cell aggregation can be supported with up to 8 serving cells. Alternatively, NR may support a different air interface other than OFDM. NR networks may include entities such as CUs and/or DUs.

[0048] In some examples, air interface access may be scheduled, with the scheduling entity (eg, base station) allocating communication resources to some or all of the devices and equipment within its coverage area or cell. In the present disclosure, as described below, a scheduling entity may be responsible for scheduling, assigning, reconfiguring, and releasing resources for one or more subordinate entities. That is, for scheduling communication, subordinate entities use the resources allocated by the scheduling entity. Base stations are not the only entities that can function as a scheduling entity. That is, in some examples, the UE may function as a scheduling entity scheduling resources for one or more subordinate entities (eg, one or more other UEs). In this example, the UE functions as a scheduling entity and other UEs use the resources scheduled by the UE for wireless communication. The UE may function as a scheduling entity in a peer-to-peer (P2P) network and/or in a mesh network. In the mesh network example, UEs may optionally communicate directly with each other in addition to communicating with a scheduling entity.

[0049] Thus, in a wireless communication network with scheduled access to time-frequency resources and having a cellular configuration, a P2P configuration, and a mesh configuration, a scheduling entity and one or more subordinate entities can communicate using scheduled resources.

[0050] As noted above, a RAN may include a CU and a DU. A NR BS (eg, gNB, 5G Node B, Node B, transmit-receive point (TRP), access point (AP)) may correspond to one or more BSs. NR cells can be configured as access cells (ACell) or data only cells (DCell). For example, a RAN (eg, a central unit or a distributed unit) may configure cells. DCells may be cells used for carrier aggregation or dual connectivity, but are not used for initial access, cell selection/reselection, or handover. In some cases, DCells cannot transmit clock signals, in some cases DCells may transmit SS. The NR BSs may transmit downlink signals to the UE indicating the cell type. Based on the cell type indication, the UE may communicate with the NR BS. For example, the UE may determine the NR of the BS to consider for cell selection, access, handover, and/or measurement based on the specified cell type.

[0051] FIG. 2 illustrates an exemplary logical architecture for a distributed radio access network (RAN) 200 that may be implemented in the wireless communication system shown in FIG. 1. 5G access node 206 may include an access node controller (ANC) 202. The ANC may be a central unit (CU) of a distributed RAN 200. A transport network interface to a next generation core network (NG-CN) 204 may terminate at an ANC. The transport network interface to neighboring next generation access nodes (NG ANs) may terminate at ANC. The ANC may include one or more TRPs 208 (which may also be referred to as BS, NR BS, Node B, 5G NB, AP, or some other term). As described above, TRP can be used interchangeably with "cell".

[0052] TRP 208 may be a DU. TRPs may be connected to one ANC (ANC 202) or more than one ANC (not shown). For example, for sharing RAN, radio as a service (RaaS), and service-specific AND deployments, a TRP may be connected to more than one ANC. The TRP may include one or more antenna ports. The TRP may be configured to individually (eg, dynamic selection) or cooperatively (eg, joint transmission) serve traffic to the UE.

[0053] Local architecture 200 can be used to illustrate the definition of a fronthaul (interface from a centralized radio controller to remote radio units). An architecture can be defined that supports fronthauling solutions for various deployment types. For example, the architecture may be based on the capabilities of the transmission network (eg, bandwidth, delay, and/or jitter).

[0054] The architecture may share features and/or components with LTE. In accordance with aspects, the next generation AN (NG-AN) 210 may support dual connectivity with the NR. NG-AN may share a common fronthaul for LTE and NR.

[0055] The architecture may allow interworking between and among TRPs 208. For example, interworking may be pre-established in TRPs and/or among TRPs via ANC 202. In accordance with aspects, no inter-TRP interface may be required/present.

[0056] In accordance with aspects, dynamic configuration of separated logic functions may be present in architecture 200. As will be described in more detail with reference to FIG. 5, Radio Resource Control (RRC) layer, Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer, Media Access Control (MAC) layer, Layer and Physical layer (PHY) can be adaptively placed on a DU or CU (for example , TRP or ANC, respectively). In accordance with some aspects, a BS may include a central unit (CU) (eg, ANC 202) and/or one or more distributed units (eg, one or more TRPs 208).

[0057] FIG. 3 illustrates an exemplary physical architecture of a distributed RAN 300, in accordance with aspects of the present disclosure. A core network centralized unit (C-CU) 302 may host core network functions. The C-CU may be centrally deployed. C-CU functionality can be offloaded (eg, to Advanced Wireless Services (AWS)) to handle peak traffic.

[0058] Centralized RAN unit (C-RU) 304 may host one or more ANC functions. Optionally, the C-RU may host core network functions locally. C-RU may have a distributed deployment. C-RU may be closer to the edge of the network.

[0059] The DU 306 may host one or more TRPs (Edge Node (EN), Edge Unit (EC), Radio Head (RH), Smart Radio Head (SRH), or the like). The DU may be located at the edges of a network with radio frequency (RF) functionality.

[0060] FIG. 4 illustrates exemplary components of BS 110 and UE 120 shown in FIG. 1 that can be used to implement aspects of the present disclosure. The BS may include TRP or gNB.

[0061] According to an example, antennas 452, DEMOD/MOD 454, processors 466, 458, 464, and/or controller/processor 480 of UE 120 may be used to perform the operations described and illustrated with reference to FIG. 9 and 11-12. According to an example, antennas 434, DEMOD/MOD 432, processors 430, 420, 438, and/or controller/processor 440 of BS 110 may be used to perform the operations described and illustrated with reference to FIG. 10-12.

[0062] As an example, one or more of the antennas 452, DEMOD/MOD 454, processors 466, 458, 464, and/or controller/processor 480 of UE 120 may be configured to perform the operations described here for beam-based UE marking. Similarly, one or more of 434, DEMOD/MOD 432, processors 430, 420, 438, and/or controller/processor 440 of base station 110 may be configured to perform the operations described herein.

[0063] For a restricted association scenario, base station 110 may be macro BS 110c in FIG. 1 and UE 120 may be UE 120y. Base station 110 may also be some other type of base station. Base station 110 may be equipped with antennas 434a-434t and UE 120 may be equipped with antennas 452a-452r.

[0064] At base station 110, transmit processor 420 may receive data from data source 412 and control information from controller/processor 440. The control information may be for a Physical Broadcast Channel (PBCH), a Physical Control Format Indicator Channel (PCFICH), a Physical Channel hybrid ARQ indicator (PHICH), physical downlink control channel (PDCCH), etc. The data may be for a physical downlink shared channel (PDSCH), and so on. Processor 420 may process (eg, encode and map to symbols) data and control information to obtain data symbols and control symbols, respectively. Processor 420 may also generate reference symbols for, for example, PSS, SSS, and cell-specific reference signal (CRS). Multiple Input/Multiple Output (MIMO) transmit processor 430 may perform spatial processing (eg, precoding) on data symbols, control symbols, and/or reference symbols, if applicable, and may provide output symbol streams to modulators (MOD) 432a-432t. Each modulator 432 may process a corresponding output symbol stream (eg, for OFDM, etc.) to obtain an output sample stream. Each modulator 432 may further process (eg, convert to analog, amplify, filter, and upconvert) the output data stream to obtain a downlink signal. Downlink signals from modulators 432a-432t may be transmitted via antennas 434a-434t, respectively.

[0065] At UE 120, antennas 452a-452r may receive downlink signals from base station 110 and may provide received signals to demodulators (DEMOD) 454a-454r, respectively. Each demodulator 454 may process (eg, filter, amplify, downconvert, and digitize) a respective received signal to obtain input signal samples. Each demodulator 454 may further process the input samples (eg, for OFDM, etc.) to obtain the received symbols. MIMO detector 456 may receive received symbols from all demodulators 454a-454r, perform MIMO detection on the received symbols, if applicable, and provide the detected symbols. Receive processor 458 may process (eg, demodulate, deinterleave, and decode) the detected symbols, provide decoded data for UE 120 to data receiver 460, and provide decoded control information to controller/processor 480.

[0066] In the uplink, at UE 120, a transmission processor 464 may receive and process data (eg, for a physical uplink shared channel (PUSCH)) from a data source 462 and control information (eg, for a physical uplink control channel communication link (PUCCH) from controller/processor 480. TX processor 464 may also generate reference symbols for the reference signal.The symbols from TX processor 464 may be precoded by TX MIMO processor 466, if applicable, further processed by demodulators 454a-454r (e.g., for SC- FDM, etc.) and transmitted to base station 110. At base station 110, uplink signals from UE 120 may be received by antennas 434, processed by modulators 432, detected by MIMO detector 436, if applicable, and further processed by processor 438 receive to receive decoded data and control information sent by UE 120. Receiver 438 may provide decoded data to data sink 439 and decoded control information to controller/processor 440.

[0067] Controllers/processors 440 and 480 may control the operation of base station 110 and UE 120, respectively. Scheduler 444 may schedule the UE for data transmission on the downlink and/or uplink. Processor 480 and/or other processors and modules at UE 120 may execute or direct, for example, the execution of the functional blocks shown in FIG. 9 and/or other processes for the methods described here and illustrated in the accompanying drawings. Processor 440 and/or other processors and modules in BS 110 may perform or direct processes for the methods described herein and illustrated in the accompanying drawings. Memories 442 and 482 may store data and program codes for base station 110 and UE 120, respectively.

[0068] FIG. 5 illustrates a diagram 500 showing examples for implementing a communications protocol stack, in accordance with aspects of the present disclosure. The illustrated communication protocol stacks may be implemented by devices operating in a 5G system. Diagram 500 illustrates a communication protocol stack including a radio resource control (RRC) layer 510, a packet data convergence protocol (PDCP) layer 515, a radio link control (RLC) layer 520, a medium access control (MAC) layer 525, and a physical (PHY) level 530. In various examples, the layers of the protocol stack may be implemented as separate software modules, parts of a processor or ASIC, parts of non-co-located devices connected by a communication link, or various combinations thereof. Co-located and non-co-located implementations may be used, eg, in the protocol stack for the network access device (eg, AN, CU and/or DU) or UE.

[0069] The first option 505-a shows a split implementation of the protocol stack, wherein in this implementation the protocol stack is split between a centralized network access device (eg, ANC 202 in FIG. 2) and a distributed network access device (eg, DU 208 in FIG. 2 ). In the first option 505-a, RRC layer 510 and PDCP 515 can be implemented by the central unit, and RLC layer 520, MAC layer 525 and PHY layer 530 can be implemented by DU. In various examples, CU and DU may be collocated or non-co-located. The first option 505-a may be useful in a macro cell, micro cell or pico cell deployment.

[0070] The second option 505-b shows a combined protocol stack implementation, where the protocol stack is implemented in a single network access device (e.g., Access Node (AN), New Radio Base Station (NR BS), New Radio Node-B (NR NB) , network node (NN), or the like). In the second option, RRC layer 510, PDCP layer 515, RLC layer 520, MAC layer 525, and PHY layer 530 may each be implemented in the AN. The second option 505-b may be useful when deploying a femtocell.

[0071] Regardless of whether the network access device implements part or all of the protocol stack, the UE may implement the entire protocol stack (eg, RRC layer 510, PDCP layer 515, RLC 520, MAC layer 525, and PHY layer 530).

[0072] FIG. 6 is a diagram showing an example of frame format 600 for NR. The transmission timeline for each of the downlink and uplink may be divided into blocks of radio frames. Each radio frame may have a predetermined duration (eg, 10 ms) and may be divided into 10 subframes, each 1 ms long, with indices 0 to 9. Each subframe may include a variable number of slots depending on the subcarrier interval. Each slot may include a different number of symbol periods (eg, 7 or 14 symbols) depending on the subcarrier spacing. Symbol periods in each slot can be assigned indices. A mini-slot is a sub-slot structure (eg 2, 3 or 4 symbols).

[0073] Each symbol in a slot may indicate a link direction (eg, DL, UL, or soft) for data transmission, and the link direction for each subframe may be dynamically switched. The link directions may be based on the slot format. Each slot may include DL/UL data as well as DL/UL control information.

[0074] In NR, a synchronization signal (SS) block is transmitted. The SS block includes a PSS, an SSS, and two PBCH symbols. The SS block may be transmitted at a fixed slot location, such as symbols 0-3, as shown in FIG. 6. PSS and SSS may be used by the UE for cell search and synchronization acquisition. PSS may provide half-frame timing, SS may provide CP length and frame timing. PSS and SSS may provide cell identity. The PBCH carries some basic system information such as downlink system bandwidth, timing information in the radio frame, SS burst rate, system frame number, and so on. SS blocks can be organized into SS bursts to support beam sweeps. Additional system information such as Remaining Minimum System Information (RMSI), System Information Blocks (SIB), Other System Information (OSI) may be transmitted on a Physical Downlink Shared Channel (PDSCH) in some subframes.

[0075] In some cases, two or more subordinate entities (eg, a UE) may communicate with each other using forward link signals. Realistic applications of such forward link transmissions may include public safety, near field services, UE-to-network relay, vehicle-to-vehicle (V2V) communications, Internet of Everything (IoE) transmissions, Internet of Things (IoT) transmissions , critical to the network task, and/or various other suitable applications. Generally, a forward link signal may refer to a signal transmitted from one slave entity (eg, UE1) to another slave entity (eg, UE2) without relaying that transmission through the scheduling entity (eg, UE or BS), even though the scheduling entity can be used for planning and/or management purposes. In some examples, direct link signals may be transmitted using licensed spectrum (as opposed to wireless LANs, which typically use unlicensed spectrum).

[0076] The UE may operate in various radio resource configurations, including a configuration associated with transmitting pilot signals using a dedicated set of resources (eg, a dedicated radio resource control (RRC) state, etc.), or a configuration associated with transmitting a pilot signal. signals using a common set of resources (eg, common RRC state, etc.). When operating in the dedicated RRC state, the UE may select a dedicated set of resources for pilot transmission to the network. When operating in the normal RRC state, the UE may select a common set of resources for pilot transmission to the network. In any case, the pilot transmitted by the UE may be received by one or more network access devices such as ANs or DUs, or parts thereof. Each receiving network access device may be configured to receive and measure pilots transmitted on a common resource set, and to receive and measure pilots transmitted on dedicated resource sets allocated to UEs for which the network access device is a member of the controlling resource set. a set of network access devices for the UE. One or more network access receivers or CUs to which the network access receiver(s) transmit(s) the pilot measurements may use the measurements to identify serving cells for the UE or initiate a serving cell change for one or more UEs.

Exemplary Prioritized Random Access Procedure

[0077] In some wireless communication systems, UEs may perform the same random access procedure with the same set of configured parameters. In these systems, no differentiation or prioritization may be available to distinguish certain types of events from other types of events. However, event prioritization can be useful in various scenarios. For example, in cases where a network supports different types of services with different goals for network access, some services may prioritize speed (for example, Ultra Reliable Low Latency Communications, or ULRRC) services, while other services may not be delay sensitive. and may prioritize power usage over access speed (eg, Machine Type Enhanced Communications Systems, or eMTS). In another example, where network segmentation allows differentiation of transport services within the same physical network, some of the differentiated services may require faster network access than other services. In addition, different types of random access events may be processed using different access delays. For example, a UE in RRC connection mode that uses a random access procedure for resynchronization may have priority over a UE in RRC idle mode that attempts to gain initial network access.

[0078] Aspects of the present disclosure prioritize random access procedures by adjusting backoff intervals and reporting backoff interval adjustments based on the priority of the random access event. By modifying the backoff adjustment parameters based on the priority associated with the random access event, the system can prioritize higher priority random access events (eg, by instructing the user equipment to retransmit immediately or with a short backoff interval) compared to a random access event with lower priority, which may be associated with longer backoff intervals.

[0079] In order to achieve prioritization among different types of UEs and different types of random access events, the backoff adjustment parameter value used in the backoff mechanism can be configured to assign different priorities, and thus different backoff periods, to different types of random access events. . Each priority j can be configured with a backoff parameter. In some embodiments, the backoff parameter may be defined as the interval between the lower bound T1 j and the upper bound T2 j for a given priority level j . The lower bound T1 j and the upper bound T2 j may be transmitted from the base station to the UE, for example, in dedicated signaling or one or more system information blocks (SIBs). When the UE prepares to invoke the random access procedure to request access, the UE delays transmission of the request to the base station by a random amount of time between T1 j and T2 j . In some cases, one or more of T1 j and T2 j may be set to 0 by the network to provide fast initial access.

[0080] In some embodiments, the UE may be configured with a backoff scaling factor associated with each priority j , as described in more detail below. The backoff scaling factor may be used, in conjunction with the backoff interval signaled by the base station, to determine the backoff period for a particular random access event. For example, the backoff scaling factor may indicate a percentage or fraction of a signaled backoff interval for the UE to use random access events in the transmission delay. When the UE prepares to invoke the random access procedure to request access, the UE delays transmission of the request to the base station by a time value equal to the product of the backoff scaling factor and the signaled backoff interval. In some cases, high priority random access events may be associated with a backoff scaling factor of 0 to provide fast network access.

[0081] In some cases, the network may experience high access loads. To provide high access load, the network may use the backoff indicator field to instruct the UE performing the random access procedure to gain access to the network to delay transmission and retransmission of certain random access requests. As discussed here, the network may prioritize some random access events by initializing the lower bound T1 j and the upper bound T2 j or the backoff scaling factor to 0 and not adjusting the backoff intervals for these random access events or making a small adjustment to the backoff intervals for these random access events (eg, by applying a small or zero backoff scaling factor to the signaled backoff interval). For low-priority random access events, the network may make increased adjustments for backoff intervals, for example, by applying a large backoff scaling factor (e.g., a backoff scaling factor approaching 1, indicating to use the maximum of the entire signaled backoff interval) to the signaled backoff interval. transmission, which may cause a UE causing low priority random access events to wait for an extended period of time before transmitting or retransmitting a random access request.

[0082] FIG. 7 illustrates exemplary operations that may be performed by a base station for prioritized random access, in accordance with an embodiment. As illustrated, operations 700 begin at 702 where the base station receives from the user equipment a random access request including information identifying the type of random access event to be raised. At 704, the base station identifies one or more backoff adjustment parameters associated with a backoff interval to be observed in the user equipment. One or more backoff adjustment parameters may be identified based at least in part on a priority associated with the random access event type. At 706, the base station transmits, to the user equipment, a random access response including the identified one or more backoff adjustment parameters.

[0083] FIG. 8 illustrates exemplary operations that may be performed by user equipment for prioritized random access, in accordance with an embodiment. As illustrated, operations 800 begin at 802 where the user device transmits, to the base station, a random access request. At 804, the user device receives, from the base station, a random access response. The random access response typically includes one or more backoff adjustment parameters. At 806, the user equipment determines a backoff interval specifying the amount of time to wait before retransmitting the random access request. The backoff interval may be determined based on one or more backoff adjustment parameters and a priority associated with the random access request type.

[0084] FIG. 9 illustrates exemplary operations that may be performed by a base station for prioritized random access, in accordance with an embodiment. As illustrated, operations 900 begin at 902 where the base station configures the user equipment with one or more backoff adjustment parameters for one or more priority levels for random access requests. In some embodiments, as described herein, one or more backoff adjustment parameters may include backoff scaling factors associated with different random access priority levels, which the UE may use to modify the base backoff interval. At 904, the base station receives, from the user equipment, a random access request. The random access request may include information identifying the type of random access event to be invoked. At 906, the base station transmits, to the user equipment, a random access response including a base backoff interval.

[0085] FIG. 10 illustrates exemplary operations that may be performed by user equipment for prioritized random access, in accordance with an embodiment. As illustrated, operations 1000 begin at 1002 where the user equipment receives, from the base station, configuration information including one or more backoff adjustment parameters. In some embodiments, as described herein, one or more backoff adjustment parameters may include scaling factors associated with different random access priority levels. At 1004, the user equipment transmits, to the base station, a random access request, and at 1006, the user equipment receives, from the base station, a random access response. The random access response typically includes information identifying a base backoff interval. At 1008, the user equipment determines a backoff interval specifying the amount of time to wait before retransmitting the random access request. The backoff interval may be determined based on a scaling factor associated with the priority level of the random access request and a base backoff interval.

[0086] FIG. 11 illustrates messages that may be exchanged between a base station and a user equipment for prioritized random access, in accordance with an embodiment. As illustrated, base station 1102 transmits, to user equipment 1104, a configuration message 1112 including one or more backoff scaling factors and random access priority levels associated with each of the one or more backoff scaling factors. The user equipment 1104 then transmits, to the base station 1102, a random access request message 1114. In response, the base station 1102 transmits a random access response message 1116. The random access response message 1116 typically includes a base backoff interval that the user equipment 1104 uses, in particular, to determine the backoff interval for retransmitting the random access request. At 1118, the user equipment calculates a backoff interval for retransmitting the random access request. As discussed, the backoff interval can be calculated as the product of the base backoff interval and the backoff scaling factor for the priority level of the random access request. After the calculated backoff time interval has elapsed, the user equipment 1104 retransmits the random access request in random access message retransmission 1120 to establish a connection with the base station. Once the user equipment 1104 has established a connection with the base station 1102, data and control communication can then be performed between the base station 1102 and the user equipment 1104.

[0087] In some embodiments, the backoff correction parameters transmitted from the base station to the user equipment may include two parameters: a priority threshold p and a scaling factor s . As discussed here, the priority information p and the scaling factor s may be signaled to the UE in configuration information from the base station or in response to granting random access. In embodiments where the UE receives the priority information p and the scaling factor s in the configuration information from the base station, the UE may use the configured scaling factor s associated with the priority information p for a particular type of random access event and the signaled backoff interval included in the random access response to calculate the backoff interval for the random access event. For example, for a random access request with a given priority level p _l associated with a backoff scaling factor s _l , the UE may calculate a backoff interval for the random access request according to a function s _l *signaled_backoff_interval.

[0088] In some embodiments, when the UE receives backoff adjustment parameters (eg, in a random access response), the UE may compare the priority of a random access event triggered in a previously transmitted random access request with a priority threshold p . If the priority of the random access event exceeds the priority threshold p , the UE does not need to adjust the backoff interval for the random access event. Otherwise, if the random access event priority is lower than the priority threshold p , the UE updates the backoff interval based on the index j (described above) and the scaling factor s . To update the backoff interval, the UE may adjust T1 j and T2 j based on the scaling factor and the a priori determined equation f(j, s) for T1 j and g(j, s) for T2 j . The functions f() and g() may be predefined as functions that receive a priority index j and a scaling factor s as input and may be known to both the network and the UE. In some cases, the functions f() and g() may be the same function. In one example, the scaling functions may be defined as f=j*s, f=s*2 ^j , f=s, and so on.

[0089] In some embodiments, each access priority level may be associated with a backoff table. The backoff tables for each priority level may be determined a priori and known to both the network and the UE, or transmitted in acknowledgment information from the base station to the UE. The backoff tables may include a plurality of entries, with an index in the backoff table associated with the backoff timing information. In some cases, the backoff timing information in the backoff table may include lower and upper bounds T1 j and T2 j , respectively, for each index in the table. In some cases, the start time may be static for each entry in the backoff table and fixed to a particular value. In some cases, the backoff timing information may include a backoff scaling factor associated with each priority level.

[0090] The user equipment may receive one parameter d as a backoff indicator included in the random access response. The UE may use the d parameter to look up a suitable backoff interval in a lookup table (which, as discussed above, may be a priori determined and known to both the network and the UE). The UE may determine a backoff interval to use in transmitting and retransmitting random access requests by searching the lookup table for the backoff interval associated with the write priority index j (e.g., two tuples {T1 j , T3 j }) associated with the received parameter d .

[0091] In some embodiments, random access events can be divided into four categories: control plane events, idle mode data plane events, connected mode data plane events, and initial attach random access. Each of these events may be associated with a different priority, as discussed above.

[0092] In some embodiments, the lookup tables may be determined a priori. A plurality of lookup tables may be established, with each lookup table associated with a different access priority level. Since there are few control plane events, and since data plane random access events can be represented by a Quality of Service (QoS) class indicator (QCI), mappings between different random access events and access priority levels can also be defined a priori. For the initial join event, since the UE may not have a QCI, the initial join event may be mapped to a default access priority.

[0093] In some embodiments, mappings between random access events and access priority levels may be configured by the network and transmitted wirelessly. These mappings may be carried, for example, in dedicated signaling or one or more System Information Blocks (SIBs), which may be periodically broadcast over the air. Because the network can configure how different types of random access events are mapped to different access priorities, configuring mappings between random access events and access priority levels can increase flexibility in handling prioritized random access events. In addition, as network conditions change, the network can dynamically adjust the mappings between random access events and access priority levels.

[0094] In some embodiments, a priori determined information and dynamically mapped information may be used together to prioritize random access events. For example, since the relative priority among random access events may be relatively static, relative priority information (eg, access priority levels) may be determined a priori and captured in a ranking index. The network may communicate mappings between ranking indexes and wireless access priority to UEs in the network. The mapping data may, in some embodiments, be carried in dedicated signaling or one or more system information blocks (SIBs).

[0095] FIG. 12 illustrates a communications device 1200 that may include various components (eg, corresponding to the tool-plus-function components) configured to perform operations for the disclosed methods, such as those shown in FIG. 7-11. Communications device 1200 includes a processing system 1202 coupled to transceiver 1208. Transceiver 1208 is configured to transmit and receive signals to communication device 1200 via antenna 1210, such as the various signals described herein. Processing system 1202 may be configured to perform function processing for communication device 1200, including processing of signals received and/or to be transmitted by communication device 1200.

[0096] The processing system 1202 includes a processor 1204 coupled to a computer-readable medium/memory 1212 via a bus 1206. In some aspects, the computer-readable medium/memory 1212 is configured to store instructions that, when executed by the processor 1204, cause the processor 1204 to execute the operations illustrated in Fig. 7-11, or other steps for performing the various methods described.

[0097] In some aspects, processing system 1202 further includes a random access request generation component 1214 to perform the operations illustrated in FIG. 7-11. In addition, the processing system 1202 includes a backoff interval determination component 1216 for performing the operations illustrated in FIG. 7-11. Random access request generation component 1214 and backoff interval determination component 1216 may be coupled to processor 1204 via bus 1206. In some aspects, random access request generation component 1214 and backoff interval determination component 1216 may be hardware circuits. In some aspects, random access request generation component 1214 and backoff interval determination component 1216 may be software components that execute and operate on processor 1204.

[0098] The methods disclosed herein comprise one or more steps or actions for implementing the described method. The steps and/or steps of the method may be interchanged with each other without departing from the scope of the claims. In other words, unless a specific order of steps or actions is given, the order and/or use of specific steps and/or actions can be modified without departing from the scope of the claims.

[0099] As used herein, a phrase referring to "at least one of" a list of elements refers to any combination of those elements, including individual elements. For example, "at least one of a, b, or c" is meant to include a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combinations of multiples of the same element (e.g., a-a, a -a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c and c-c-c or any other order of a, b and c).

[0100] As used herein, the term "definition" covers a wide variety of actions. For example, “determining” may include calculating, computing, processing, obtaining, examining, searching (eg, searching in a table, database, or other data structure), establishing, and the like. In addition, “determining” may include receiving (eg, receiving information), accessing (eg, accessing data in memory), and the like. In addition, "determining" may include permission, selection, selection, creation, and the like.

[0101] The previous description is provided to enable any person skilled in the art to put into practice the various aspects described herein. Various modifications to these aspects will be apparent to those skilled in the art, and the general principles defined here may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown here, but are to be kept to their fullest extent consistent with the terminology of the claims, and reference to an element in the singular is intended to mean "one and only one", unless specifically indicated thus, and "one or more". Unless otherwise noted, the term "some" refers to one or more. All structural and functional equivalents of elements of the various aspects described in this disclosure that are known or will later become known to those skilled in the art are expressly incorporated herein by reference and are intended to be included in the claims. Moreover, nothing disclosed herein is intended to be publicly provided, whether or not such disclosure is expressly set forth in the claims. No claim element shall be construed under the provisions of 35 U.S.C. §112, sixth paragraph, unless that element is explicitly listed using the phrase “means for” or, in the case of a method claim, the element is not explicitly listed using the phrase “step for”.

[0102] The various operations of the methods described above may be performed by any suitable means capable of performing the respective functions. The means may include various hardware and/or software components and/or modules, including, but not limited to, a circuit, an application specific integrated circuit (ASIC), or a processor. In general, where there are operations illustrated in the drawings, these operations may have corresponding equivalent means-plus-function components with similar numbering.

[0103] Various illustrative logical blocks, modules, and circuits described in connection with the present disclosure may be implemented or implemented with a general purpose processor, digital signal processor (DSP), application specific integrated circuit (ASIC), field programmable gate array (FPGA) or other programmable logic device (PLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof, designed to perform the functions described in this document. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any commercially available processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in combination with a DSP core, or any other similar configuration.

[0104] When implemented in hardware, an exemplary hardware configuration may include a processing system at a wireless node. The processing system may be implemented with a bus architecture. The bus may include any number of interconnecting buses and bridges, depending on the particular application of the processing system and general design constraints. A bus may link together various circuits, including a processor, computer-readable media, and a bus interface. A bus interface can be used to connect a network adapter to, among other things, a processing system via a bus. The network adapter can be used to implement signal processing functions at the PHY level. In the case of user terminal 120 (see FIG. 1), a user interface (eg, keyboard, display, mouse, joystick, etc.) may also be connected to the bus. The bus may also interface with various other circuits such as timing sources, peripherals, voltage regulators, power management circuits, and the like, which are well known in the art and therefore will not be described further. The processor may be implemented by one or more general purpose and/or special purpose processors. Examples include microprocessors, microcontrollers, digital signal processors, and other circuits that can execute software. Those skilled in the art will appreciate how best to implement the described functionality for a processing system, depending on the particular application and the general design constraints imposed on the overall system.

[0105] When implemented in software, the functions may be stored or transmitted as one or more instructions or code on a computer-readable medium. Software shall be construed broadly to mean instructions, data, or any combination thereof, which may be referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. Computer-readable media includes both computer storage media and communication media, including any media that facilitates the transfer of a computer program from one place to another. The processor may be responsible for bus administration and general processing, including execution of program modules stored on computer-readable media. A computer-readable storage medium may be coupled to the processor such that the processor can read information from, and write information to, the storage medium. Alternatively, the storage medium may be integrated into the processor. By way of example, computer-readable media may include a transmission line, a data-modulated carrier wave, and/or a computer-readable storage medium with instructions stored thereon separately from the wireless node, all of which may be accessed by a processor via a bus interface. Alternatively or additionally, computer-readable media, or any portion thereof, may be integrated into the processor, such as in the case of cache and/or conventional register files, for example. Examples of computer readable storage media may include, by way of example, RAM (Random Access Memory), Flash Memory, ROM (Read Only Memory), EPROM (Programmable Read Only Memory), EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically Erasable Memory). read-only memory), registers, magnetic disks, optical disks, hard disk drives, or any other storage medium, or any combination thereof. Computer readable media may be embodied in a computer program product.

[0106] A software module may contain a single instruction or multiple instructions, and may be distributed across several different code segments, among different programs, and across multiple media. Computer-readable media may contain a number of program modules. Program modules include instructions that, when executed by a device such as a processor, cause the processing system to perform various functions. The software modules may include a transmit module and a receive module. Each software module may reside on a single storage device or be distributed across multiple storage devices. As an example, a program module may be loaded into RAM from a hard disk drive when a startup event occurs. During the execution of a program module, the processor may load some of the instructions into the cache to increase access speed. One or more cache lines may then be loaded into a shared registry file for execution by the processor. With reference to the functionality of a software module below, it will be understood that such functionality is implemented by the processor when executing instructions from that software module.

[0107] In addition, any connection is properly defined as a computer-readable medium. For example, if software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared (IR), radio, and microwave, then coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the media definition. The magnetic disc and optical disc as used herein include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disc, and Blu-ray® disc, where magnetic discs typically reproduce data magnetically. , while optical discs reproduce data optically using lasers. Thus, in some aspects, computer-readable media may comprise non-transitory computer-readable media (eg, tangible media). In addition, for other aspects, computer-readable media may comprise temporary computer-readable media (eg, a signal). Combinations of the above should also be included in the scope of computer-readable media.

[0108] Thus, some aspects may include a computer program product for performing the operations presented herein. For example, such a computer program product may include a computer-readable medium having instructions stored (and/or encoded) thereon, the instructions being executed by one or more processors to perform the operations described herein. For example, instructions for performing the operations described in this document and in the attached drawings.

[0109] In addition, it should be understood that modules and/or other appropriate means for performing the methods and methods described herein may be downloaded and/or otherwise obtained by the user terminal and/or base station, as applicable. For example, such a device may be associated with a server to facilitate the transfer of a means to perform the methods described herein. Alternatively, the various methods described herein may be provided with storage media (eg, RAM, ROM, physical storage media such as a compact disk (CD) or floppy disk, etc.), so that the user terminal and /or the base station may receive various methods after linking or providing the storage medium to the device. In addition, any other suitable method may be used to provide the methods and techniques described herein to a device.

[0110] It should be understood that the claims are not limited to the exact configuration and components illustrated above. Various modifications, changes and variations may be made to the arrangement, operation and details of the methods and apparatus described above without departing from the scope of the claims.

Claims (46)

1. A method for wireless communication via a base station, comprising the steps of: configuring the user equipment with backoff adjustment parameters for one or more priority levels for random access requests, wherein the configured backoff adjustment parameters comprise a lower bound and an upper bound for a backoff interval for each of said one or more priority levels; receiving a random access request from the user equipment; and transmitting to the user equipment a random access request response including a base backoff interval to modify the backoff interval in the user equipment based on the priority of the random access request. 2. The method of claim 1, wherein the random access request includes information identifying the type of random access event to be triggered. 3. The method of claim 1, wherein said one or more backoff adjustment parameters comprise a priority threshold and a scaling factor. 4. The method of claim 1, wherein said one or more backoff adjustment parameters comprise a lookup table including a plurality of priority levels associated with different types of random access events, and a backoff scaling factor associated with each priority level. 5. The method of claim 4, wherein the access priority information and backoff parameter lookup tables are communicated to the user equipment via one or more system information blocks (SIBs). 6. The method of claim 1, further comprising sending to the user equipment a mapping between ranking index information for each type of random access event and an access priority. 7. The method of claim 6, wherein said mapping is transmitted to the user equipment via dedicated signaling or one or more system information blocks (SIBs). 8. A method for wireless communication by means of user equipment, comprising the steps of: receiving from the base station configuration information including backoff adjustment parameters for one or more priority levels for random access requests, the configuration information comprising a lower bound and an upper bound for a backoff interval for each of said one or more priority levels; transmitting a random access request to the base station; receiving from the base station a response to the random access request including a base backoff interval; and based on the backoff adjustment parameter associated with the priority of the random access request and the base backoff interval, a backoff interval is determined specifying the amount of time to wait before retransmission of the random access request, wherein the determined backoff interval is selected based on the lower and upper bounds for the interval transmission delay. 9. The method of claim 8, wherein said one or more backoff adjustment parameters comprise a priority threshold and a scaling factor. 10. The method of claim 8, wherein said backoff interval determination comprises: upon determining that a priority associated with a random access request type is lower than a priority threshold, adjusting the backoff interval based on a scaling factor, a priority associated with the random access request type, and a base backoff interval. 11. The method of claim 8, wherein said one or more backoff adjustment parameters comprise an index into a lookup table. 12. The method of claim 11, wherein said backoff interval determination comprises identifying a backoff scaling factor associated with an index in a lookup table associated with a random access request type priority. 13. The method of claim 8, further comprising receiving access priority information and backoff parameter lookup tables from the base station. 14. The method of claim 13, wherein the access priority information and backoff parameter lookup tables are received from the base station via one or more system information blocks (SIBs). 15. The method of claim 8, further comprising receiving from the base station a mapping between ranking index information for each type of random access event and an access priority. 16. The method of claim 15, wherein said mapping is received from the base station via dedicated signaling or one or more system information blocks (SIBs). 17. Device for wireless communication, containing: a processor configured to: configure the user equipment with backoff adjustment parameters for one or more priority levels for random access requests, wherein the configured backoff adjustment parameters comprise a lower bound and an upper bound for a backoff interval for each of said one or more priority levels, receive a random access request from the user equipment, and transmitting to the user equipment a random access request response including a base backoff interval to modify the backoff interval in the user equipment based on the priority of the random access request; and memory. 18. The apparatus of claim 17, wherein the random access request includes information identifying the type of random access event to be triggered. 19. The apparatus of claim 17, wherein said one or more backoff adjustment parameters comprise a priority threshold and a scaling factor. 20. The apparatus of claim 17, wherein said one or more backoff adjustment parameters comprise a lookup table including a plurality of priority levels associated with different types of random access events and a backoff scaling factor associated with each priority level. 21. The apparatus of claim 20, wherein the access priority information and backoff parameter lookup tables are communicated to the user equipment via one or more system information blocks (SIBs). 22. The apparatus of claim 18, further comprising transmitting, to the user equipment, a mapping between the ranking index information for each type of random access event and the access priority. 23. The apparatus of claim 22, wherein said mapping is communicated to the user equipment via dedicated signaling or one or more system information blocks (SIBs). 24. A device for wireless communication, comprising: a processor configured to: receive from the base station configuration information including backoff adjustment parameters for one or more priority levels for random access requests, wherein the configured backoff adjustment parameters comprise a lower bound and an upper bound for a backoff interval for each of said one or more priority levels priority, send a random access request to the base station, receive from the base station a random access response including a base backoff interval, and based on the backoff adjustment parameter associated with the priority of the random access request and the base backoff interval, determine a backoff interval specifying the amount of time to wait before retransmission of the random access request, wherein the determined backoff interval is selected based on the lower and upper bounds for the interval transfer delays; and memory. 25. The apparatus of claim 24, wherein said one or more backoff adjustment parameters comprise a priority threshold and a scaling factor, wherein the processor is configured to determine the backoff interval by: determining that a priority associated with a random access request type lower than the priority threshold, backoff interval adjustments based on the scaling factor, the priority associated with the random access request type, and the base backoff interval. 26. The apparatus of claim 24, wherein said one or more backoff adjustment parameters comprise an index in a lookup table, wherein the processor is configured to determine the backoff interval by identifying a scaling factor associated with an index in a lookup table associated with a request type priority. random access. 27. The apparatus of claim 24, wherein the processor is further configured to receive access priority information and backoff parameter lookup tables from the base station. 28. The apparatus of claim 24, wherein the processor is further configured to receive from the base station a mapping between ranking index information for each type of random access event and an access priority.

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