RU2789818C1 - Systems and methods for enhanced random access procedure - Google Patents

Abstract

FIELD: wireless communication.

SUBSTANCE: to realise the technical result, the method for random access includes the stage of the wireless communication apparatus transmitting a first message including a header and payload to the network. The wireless communication apparatus receives a second message from the network in response to the first message. Herewith, the second message constitutes a MAC PDU including one or more MAC subPDUs, and each MAC subPDU of the one or more MAC subPDUs includes at least one of the following: (a) a first MAC subtitle only with a backoff indicator, (b) a second MAC subtitle and a SuccessRAR, or (c) a third MAC subtitle and a backup RAR.

EFFECT: possibility of supporting a two-stage random access procedure and a four-stage random access procedure using signalling of switching between said procedures.

20 cl, 8 dwg

Description

The field of technology to which the invention belongs

The disclosure relates generally to wireless communications and, in particular, to systems and methods for an improved random access procedure.

State of the art

In fifth generation (5G) New Radio (New Radio, NR) mobile networks, before the user equipment (UE) can send data to the base station (BS), the UE must acquire uplink timing and downlink timing from the BS. Uplink time synchronization can be achieved by performing a random access procedure. To meet the demand for faster and more efficient communication, the random access procedure needs to be improved.

The essence of the invention

Approximate implementation options, disclosed in this document, are aimed at solving problems related to one or more of existing problems, as well as to provide additional functions that will become obvious when referring to the following detailed description in combination with accompanying drawings. In accordance with various embodiments in this document, approximate systems, methods, devices and computer software products are disclosed. However, it is clear that these implementation options are presented as examples and are not limiting, and for specialists in this field of equipment who read this disclosure, it will be obvious that various modifications of the disclosed embodiments can be performed without going beyond this disclosure.

In one embodiment, a method performed by a wireless communication device includes: receiving, from a wireless communication node, information indicative of a value; comparing the randomly generated value with the value; selecting, based on the comparison, either a 4-way random access procedure or a 2-way random access procedure to access the wireless node; and transmitting a first message for accessing the wireless node, the content of the first message being based on the selection of the 4-way random access procedure or the 2-way random access procedure.

In another embodiment, the device includes a processor configured to implement the method. The method includes receiving, by the wireless communication device from the wireless communication node, information indicating a value; comparing, by the wireless communication device, the randomly generated value with the value; selecting, by the wireless communication device based on the comparison, either a 4-way random access procedure or a 2-way random access procedure to access the wireless node; and transmitting, by the wireless communication device, a first message to access the wireless node, the contents of the first message being based on the selection of the 4-way random access procedure or the 2-way random access procedure.

In yet another embodiment, the computer-readable storage medium contains code stored thereon, wherein the code, when executed by a processor, causes the processor to implement a method. The method includes receiving, by the wireless communication device from the wireless communication node, information indicating a value; comparing, by the wireless communication device, the randomly generated value with the value; selecting, by the wireless communication device based on the comparison, either a 4-way random access procedure or a 2-way random access procedure to access the wireless node; and transmitting, by the wireless communication device, a first message to access the wireless node, the contents of the first message being based on the selection of the 4-way random access procedure or the 2-way random access procedure.

In one embodiment, a method performed by a wireless communication device includes: reception, from a wireless communication unit, information indicating many values, and many values, respectively, corresponds to many parameters; choosing one of a variety of options; a comparison of a random way developed with a value from many values, and the value selected from many values corresponds to the selected access control parameter; the choice, based on a comparison, either a 4-storey procedure of arbitrary access, or the second 2-stage procedure of arbitrary access for access to a wireless unit; And the transfer of the first message for access to the wireless unit, and the content of the first message is based on the choice of a 4-stage procedure of arbitrary access or a 2-stage procedure of arbitrary access.

In another embodiment, the device includes a processor configured to implement the method. The method includes receiving, by the wireless communication device from the wireless communication node, information indicating a plurality of values, the plurality of values corresponding to the plurality of parameters respectively; selecting, by the wireless communications device, one of a plurality of options; comparing, by the wireless communication device, the randomly generated value with a value from the plurality of values, the value selected from the plurality of values corresponding to the selected access control parameter; selecting, by the wireless communication device based on the comparison, either a 4-way random access procedure or a second 2-way random access procedure to access the wireless node; and transmitting, by the wireless communication device, a first message to access the wireless node, the contents of the first message being based on the selection of the 4-way random access procedure or the 2-way random access procedure.

In yet another embodiment, the computer-readable storage medium contains code stored thereon, wherein the code, when executed by a processor, causes the processor to implement a method. The method includes receiving, by the wireless communication device from the wireless communication node, information indicating a plurality of values, the plurality of values corresponding to the plurality of parameters respectively; selecting, by the wireless communications device, one of a plurality of options; comparing, by the wireless communication device, the randomly generated value with a value from the plurality of values, the value selected from the plurality of values corresponding to the selected access control parameter; selecting, by the wireless communication device based on the comparison, either a 4-way random access procedure or a second 2-way random access procedure to access the wireless node; and transmitting, by the wireless communication device, a first message to access the wireless node, the contents of the first message being based on the selection of the 4-way random access procedure or the 2-way random access procedure.

In one embodiment, a method performed by a wireless communications device includes: receiving, from a wireless communications node, information indicative of a timer; selecting, in response to determining that the timer is in an active state, a 4-way random access procedure for accessing the wireless node; selecting, in response to determining that the timer is in the idle state, either a 4-way random access procedure or a 2-way random access procedure to access the wireless node; and transmitting a first message for accessing the wireless node, the contents of the first message being based on the selection of the 4-way random access procedure or the 2-way random access procedure.

In another embodiment, the device includes a processor configured to implement the method. The method includes receiving, by the wireless communication device from the wireless communication node, information indicative of a timer; selecting, by the wireless communication device, in response to determining that the timer is in the active state, a 4-way random access procedure to access the wireless node; selecting, by the wireless communication device, in response to determining that the timer is in the idle state, either a 4-way random access procedure or a 2-way random access procedure to access the wireless node; and transmitting, by the wireless communication device, a first message to access the wireless node, the contents of the first message being based on the selection of the 4-way random access procedure or the 2-way random access procedure.

In yet another embodiment, the computer-readable storage medium has code stored thereon, wherein the code, when executed by a processor, causes the processor to implement a method. The method includes receiving, by the wireless communication device from the wireless communication node, information indicative of a timer; selecting, by the wireless communication device, in response to determining that the timer is in the active state, a 4-way random access procedure to access the wireless node; the choice, a wireless device, in response to the determination that the timer is inactive, or a 4-storey procedure of arbitrary access, or a 2-stage procedure of arbitrary access for access to a wireless unit; And the transfer, wireless communication device, the first message for access to the wireless unit node, and the content of the first message is based on the choice of a 4-storey procedure of arbitrary access or a 2-etap procedure of arbitrary access.

In one embodiment, a method performed by a wireless communication device includes: transmitting a first message for accessing a wireless node, the contents of the first message being based on a selection of a 4-way random access procedure or a 2-way random access procedure; receiving, from the wireless communication node, in response to the transmission of the first message, a second message indicating the first timer; and selecting, in response to determining that the timer is in the idle state, either a 4-way random access procedure or a 2-way random access procedure to retransmit the first message.

In another embodiment, the device includes a processor configured to implement the method. The method includes transmitting, by the wireless communication device, a first message to access the wireless node, the contents of the first message being based on a selection of a 4-way random access procedure or a 2-way random access procedure; receiving, by the wireless communication device from the wireless communication node, in response to the transmission of the first message, a second message indicating the first timer; and selecting, by the wireless communication device, in response to determining that the timer is in the idle state, either a 4-way random access procedure or a 2-way random access procedure to retransmit the first message.

In another embodiment, the machine -readable media of the information has the code stored on it, and the code when it executes the processor, orders the processor to implement the method. The method includes transmission, a wireless device, the first message for access to the wireless unit node, and the content of the first message is based on the choice of a 4-storey procedure of arbitrary access or a 2-storey procedure of arbitrary access; reception, a wireless device from a wireless unit, in response to the transfer of the first message, the second message indicating the first timer; And the choice, a wireless device, in response to the determination that the timer is inactive, or a 4-storey procedure of arbitrary access, or a 2-storey procedure of arbitrary access for re-transmission of the first message.

The above and other aspects and their implementation are described in more detail in the following description with reference to the drawings and in the claims.

Brief description of the drawings

Various exemplary embodiments of the present solution are described in detail below with reference to the accompanying figures or drawings. The drawings are provided for purposes of illustration only and simply depict exemplary embodiments of the present solution in order to facilitate the reader's understanding of the present solution. Thus, the drawings should not be construed as limiting the breadth, scope, or applicability of this solution. It should be noted that, for clarity and ease of illustration, these drawings are not necessarily drawn to scale.

1 is an example of a cellular communication network in which the technologies and other aspects disclosed herein may be implemented in accordance with an embodiment of the present disclosure.

2 is a block diagram of an exemplary base station and an exemplary user equipment device in accordance with some embodiments of the present disclosure.

3 is an example of a 4-way random access procedure in accordance with some embodiments of the present disclosure.

4 is an example of a 2-way random access procedure in accordance with some embodiments of the present disclosure.

5 is a flowchart illustrating an exemplary process for an extended random access procedure using a RACH type selection factor, in accordance with some embodiments of the present disclosure.

6 is a flowchart illustrating another exemplary process for an extended random access procedure using a RACH type selection factor, in accordance with some embodiments of the present disclosure.

7 is a flowchart illustrating an exemplary process for an extended random access procedure using a RACH type selection timer, in accordance with some embodiments of the present disclosure.

8 is a flowchart illustrating an exemplary process for an extended random access procedure with backoff indication, in accordance with some embodiments of the present disclosure.

Detailed description of the invention

Various exemplary embodiments of the present solution are described below with reference to the accompanying drawings in order to enable a person skilled in the art to make and use the present solution. As will be apparent to those skilled in the art, after reading this disclosure, various changes or modifications to the examples described herein may be made without departing from the scope of this decision. Thus, the present solution is not limited to the exemplary embodiments and applications described and illustrated herein. In addition, the specific order or hierarchy of steps in the methods disclosed herein are merely exemplary approaches. Based on design preferences, the specific order or hierarchy of steps of the disclosed methods or processes may be changed while remaining within the scope of the present disclosure. Thus, those skilled in the art will appreciate that the methods and techniques disclosed herein represent the various steps or steps in an exemplary order, and the present disclosure is not limited to a particular order or hierarchy presented, unless explicitly stated otherwise.

A. Network environment and computing environment

FIG. 1 shows an exemplary wireless communication network and/or system 100 in which the methods disclosed herein may be implemented, in accordance with an embodiment of the present disclosure. In the following description, wireless communication network 100 can be any wireless network, such as a cellular network or a narrowband Internet of Things (NB-IoT) network, and is referred to herein as "network 100". Such an exemplary network 100 includes a base station 102 (hereinafter referred to as "BS 102") and a user equipment device 104 (hereinafter referred to as "UE 104") that can communicate with each other via a communication channel 110 (e.g., a wireless channel). communication), and a cluster of cells 126, 130, 132, 134, 136, 138, and 140 covering geographic area 101. In FIG. , 134, 136, 138, and 140 may include at least one base station operating with dedicated bandwidth to provide adequate radio coverage for its intended user.

For example, BS 102 may operate with dedicated channel bandwidth to provide adequate coverage to UE 104. BS 102 and UE 104 may communicate via downlink radio frame 118 and uplink radio frame 124, respectively. Each radio frame 118/124 may be further divided into subframes 120/127, which may include data symbols 122/128. In the present disclosure, BS 102 and UE 104, respectively, are described herein generally as non-limiting examples of "communication node" (or "wireless communication node") and "communication device" (or "wireless communication device") that can be used on practice disclosed in this document methods. Such communication nodes and devices are capable of supporting wireless and/or wired communication in accordance with various embodiments of the present solution.

2 shows a block diagram of an exemplary wireless communication system 200 for transmitting and receiving wireless communication signals, such as OFDM/OFDMA signals, in accordance with some embodiments of the present solution. System 200 may include components and elements configured to support known or conventional operating functions that do not need to be described in detail herein. In one exemplary embodiment, system 200 may be used to transmit (eg, send and receive) data symbols in a wireless communication environment, such as wireless communication environment 100 as shown in FIG. 1 and described above.

System 200 typically includes a base station 202 (hereinafter referred to as "BS 202") and a user equipment device 204 (hereinafter referred to as "UE 204"). The BS 202 includes a BS transceiver (base station) module 210, a BS antenna 212, a BS processor module 214, a BS memory module 216, and a network communication module 218, each module being connected and interconnected with each other via a communication bus 220 as necessary. The UE 204 includes a UE (user equipment) transceiver module 230, a UE antenna 232, a UE memory module 234, and a UE processor module 236, each module being connected and interconnected to each other via a communication bus 240 as needed. The BS 202 communicates with the UE 204 via a communication channel 250, which can be any wireless channel or other medium suitable for data transmission as described herein.

As will be understood by those skilled in the art, system 200 may further include any number of modules other than those shown in FIG. Those skilled in the art will appreciate that the various illustrative blocks, modules, circuits, and processing logic described in connection with the embodiments disclosed herein may be implemented in hardware, computer-readable software, firmware, or any their practical combination. To clearly illustrate this interchangeability and compatibility of hardware, firmware, and software, various illustrative components, blocks, modules, circuits, and steps are described generally in terms of their functionality. Whether such functionality is implemented as hardware, firmware, or software may depend on the particular application and design constraints imposed on the overall system. Those familiar with the concepts described herein may implement such functionality appropriately for each particular application, but such implementation decisions should not be interpreted as limiting the scope of this disclosure.

In accordance with some embodiments, UE transceiver 230 may be referred to herein as "uplink" transceiver 230, which includes a radio frequency (RF) transmitter and a radio frequency receiver, each of which contains circuitry that is coupled to antenna 232. Duplex Switch (not shown) may alternatively connect an uplink transmitter or receiver to the uplink antenna in time duplex mode. Similarly, in accordance with some embodiments, BS transceiver 210 may be referred to herein as "downlink" transceiver 210, which includes an RF transmitter and an RF receiver, each of which contains circuitry that is connected to an antenna 212 The downlink duplex switch may alternatively connect the downlink transmitter or receiver to the downlink antenna 212 in time duplex mode. The operation of the two transceiver modules 210 and 230 can be time coordinated so that the uplink receiver circuit is connected to the uplink antenna 232 to receive transmissions on the wireless transmission link 250 at the same time that the downlink transmitter is connected to the antenna 212 downlink. In some embodiments, there is close timing with a minimum guard time between changes in the duplex direction.

UE transceiver 230 and base station transceiver 210 are configured to communicate via wireless data link 250 and cooperate with a suitably configured RF antenna device 212/232 that can support a particular wireless communication protocol and modulation scheme. In some exemplary embodiments, UE transceiver 210 and base station transceiver 210 are configured to support industry standards such as Long Term Evolution (LTE) and emerging 5G standards, and the like. However, it should be noted that the present disclosure is not necessarily limited to the application of a particular standard and associated protocols. In contrast, UE transceiver 230 and base station transceiver 210 may be configured to support alternative or additional wireless communication protocols, including future standards or variations thereof.

In accordance with various options for the implementation of BS 202, for example, the next generation node (GNODEB or GNB), a developed node B (ENB) that serves ENB, target ENB, a femo -stem, a pico or an acceptance point (TRP), can be. In some embodiments, UE 204 can be embodied in the form of user devices of various types, such as a mobile phone, a smartphone, a personal digital assistant (PDA), a tablet computer, a portable computer, a computing device, etc. Modules 214 and 236 processing are implemented or can be implemented using a general purpose processor, memory addressable in content, digital signal processor, specialized integrated circuit, a programmable valve matrix, any suitable programmable logical device, discrete valve or transistor logical scheme, discrete components hardware or any of their combinations designed to perform the functions described in this document. Thus, the processor can be implemented in the form of a microprocessor, controller, microcontroller, final machine, etc. The processor can also be implemented in the form of a combination of computing devices, for example, combinations of the digital signal and microprocessor processor, many microprocessors, one or more microprocessors in combination with the core of the digital signal processor or any other such configuration.

In addition, the steps of a process, method, or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, firmware, software, software module executed by processing modules 214 and 236, respectively, or any practical combination thereof. Memory modules 216 and 234 may be implemented as RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or any other form of storage media known in the art. In this regard, memory modules 216 and 234 may be coupled to processing modules 210 and 230, respectively, such that processing modules 210 and 230 can read information from and write information to memory modules 216 and 234, respectively. Memory modules 216 and 234 may also be integrated into their respective processing modules 210 and 230. In some embodiments, memory modules 216 and 234 may each include a cache for storing temporary variables or other intermediate information during execution of instructions to be executed by processing modules 210 and 230, respectively. Each of the memory modules 216 and 234 may also include non-volatile memory for storing instructions to be executed by the processing modules 210 and 230, respectively.

Network communication module 218 is typically hardware, software, firmware, processing logic, and/or other components of base station 202 that provide bi-directional communication between base station transceiver 210 and other network components and communication nodes, configured to communicate with base station 202. For example, network communication module 218 may be configured to support Internet or WiMAX traffic. In a typical deployment, without limitation, the network communication module 218 provides an 802.3 Ethernet interface so that the base station transceiver 210 can communicate with a traditional Ethernet-based computer network. Thus, the network communication module 218 may include a physical interface for connecting to a computer network (eg, a mobile switching center (MSC)). The terms "configured for", "capable of", and combinations thereof, as used herein in relation to a specified operation or function, refer to a device, component, circuit, structure, machine, signal, etc., that is physically constructed, programmed, formatted and/or configured to perform the specified operation or function.

B. Exemplary random access procedures

3 shows an example of a 4-round random access procedure 300 in accordance with some embodiments of the present disclosure. As shown in FIG. 3, a 4-round random access (RACH) procedure 300 is performed between a BS 302 (eg, gNB) and a UE 304. BS 302 and UE 304 may be the same or similar to BS 202 and UE 204 in FIG. 2 , respectively. In some embodiments, in step 1 (306), UE 304 transmits a random access channel (RACH) preamble or a physical random access channel (PRACH) preamble in message 1 (Msg1) on the uplink random access channel (RACH) to the BS 302. On step 2 (308), after the preamble is successfully received by the BS 302, the BS 302 sends message 2 (Msg2) back to the UE 304, in which a medium access control (MAC) random access response (RAR ) can be included as a response to the preamble. In step 3 (310), after receiving the MAC RAR with the corresponding random access preamble (RAP) identifier (ID), the UE 304 transmits message 3 (Msg3) to the BS 302 with the grant carried in the RAR MAC. In step 4 (312), after receiving Msg3, BS 302 sends message 4 (Msg4) back to UE 304, which may include a collision resolution ID to resolve collisions. In some embodiments, to reduce latency and speed up the initial access procedure, a 2-round random access procedure may be used, as described below with reference to FIG.

Figure 4 shows an exemplary 2-stage random access procedure 400 in accordance with some embodiments of the present disclosure. In some embodiments, the 2-round random access procedure (RACH) 400 may complete the four steps shown in FIG. 3 in two messages or two steps. In some embodiments, at least some of the content of Msg1 and Msg3 in the 4-way RACH is included in Msg1 of the 2-way RACH, and at least some of the content of Msg2 and Msg4 (RAR and decollision) in the 4-way RACH is included in Msg2 of the 2-way RACH. staged RACH. As shown in FIG. 4, a 2-way random access procedure 400 is performed between a BS 402 (eg, gNB) and a UE 404. BS 402 and UE 404 may be the same or similar to the BS 202 and UE 204 shown in FIG. 2, respectively. In some embodiments, in step 1 (406), UE 404 transmits Msg1, which includes a preamble and data payload, to BS 402 to access BS 402. In some embodiments, the payload may be optional. In some implementations, the preamble may be optional. In step 2 (408), the BS 402 transmits Msg2 as a response to Msg1 to the UE 404. Details of the 2-way random access procedure are described below.

C. Random Access (RA) type selection between 2-round RACH and 4-round RACH

In some embodiments, when both the 2-way RA configuration and the 4-way RA configuration are broadcast in system information (e.g., in a System Information Type 1 Block (SIB1)), RA type selection is performed, for example, between random access procedure (2-way RACH) and 4-way random access procedure (4-way RACH). For example, in some embodiments, RA type selection may be performed for step 1 of the 2-way random access procedure.

In some embodiments, the following alternatives or options may be considered or implemented when selecting an RA type between 2-round RACH and 4-round RACH. These alternatives or options may be performed individually or in combination. Briefly, a decision based on "RACH Type Selection Factor" may be considered or implemented in a first alternative (ALT 1), a decision based on a "RACH Type Selection Timer" may be considered or implemented in a second alternative (ALT 2 ), and a backoff indicator based solution may be considered or implemented in a third alternative (ALT 3), as described in more detail herein below.

ALT 1: Decision based on "RACH type selection factor"

In some embodiments, by (or after, in response to, after, when) configuring a RACH type selection factor (which is described in more detail below), a UE (e.g., UE 404) may derive, obtain, or determine a random number or a randomly generated number "rand", for example, in the range 0 ≤ rand < 1. In other embodiments, "rand" may be in other ranges. In some embodiments, "rand" may be generated randomly by the UE or another device. In some embodiments, the UE may compare "rand" with a value indicated by a RACH type selection coefficient. If "rand" is less than (or less than or equal to, or greater than or greater than or equal to) than the value indicated by the RACH type selection coefficient, the UE is allowed to select the 2-stage RACH. Otherwise, the UE selects the 4-round RACH.

In some embodiments, by (or after, in response to, after, when) configuring the RACH type selection factor, the UE may derive, obtain, or determine a random number or a random number "rand", e.g., in the range 0 ≤ rand < 1. In other embodiments, "rand" may be in other ranges. In some embodiments, "rand" may be generated randomly by the UE or another device. In some embodiments, the UE may compare "rand" with a value indicated by a RACH type selection factor. If "rand" is less than (or less than or equal to, or greater than or greater than or equal to) than the value indicated by the RACH type selection factor, the UE shall select the 2-round RACH. Otherwise, the UE must select the 4-way RACH.

In some embodiments, in addition to the ratio-based decision, some other criteria may also be considered when selecting the type of RA (e.g., RSRP threshold and 2-round RACH may only be selected if the measured RSRP exceeds the RSRP threshold). Thus, coefficient-based RA type selection can be used in the following two ways: Alt1: coefficient-based decision is used to determine whether 2-way RACH is allowed; and Alt2: A ratio based decision is used to determine whether a 2-stage RACH should be selected. In Alt1, a coefficient-based decision can be used along with other criteria, and a 2-way RACH can only be selected if the 2-way RACH selection is allowed by all criteria. In Alternative 2, a coefficient based decision should be used if 2-way RACH is allowed, which may be determined by other criteria.

In some embodiments, the following alternatives or options may be considered or implemented for RACH type selection factor configuration.

In Alternative 1 configuration of the RACH type selection coefficient, the RACH type selection coefficient may be configured for each access category. With (based on, using) the "RACH type selection factor" configured for each access category, the UE can first determine the access category and then use the corresponding "RACH type selection factor" to determine which random access procedure (e.g., 2-way random access procedure or 4-way random access procedure) must be selected.

In Alternative 2 RACH type selection coefficient configuration, the RACH type selection coefficient may be configured for the Unified Access Control (UAC)-BarringInfoSet. With (based on, using) the "RACH Type Selection Factor" configured for each access category, the UE may first determine the UAC-BarringInfoSet and then use the corresponding "RACH Type Selection Factor" to determine which random access procedure (e.g. , 2-way random access procedure or 4-way random access procedure) must be selected.

In Alternative 3 RACH type selection factor configuration, the RACH type selection factor may be configured for each access ID. With (based on, using) the "RACH Type Selection Factor" configured for each access category, the UE may first determine the access identifier and then use the corresponding "RACH Type Selection Factor" to determine which random access procedure (e.g., 2-way random access procedure or 4-way random access procedure) must be selected.

In the RACH Type Selection Factor Configuration Alternative 4, the RACH Type Selection Factor may be configured for each Public Land Mobile Network (PLMN). With (based on, using) the "RACH type selection factor" configured for each PLMN, the UE may first determine the PLMN and then use the corresponding "RACH type selection factor" to determine which random access procedure (e.g., 2- step random access procedure or 4-step random access procedure) must be selected.

In the RACH type selection factor configuration alternative 5, the RACH type selection factor may be configured to trigger various triggers or trigger events of the RACH procedure. In some embodiments, the following RACH procedure triggers or trigger events may be considered or implemented: (a) initial access from radio resource control (RRC)_IDLE; (b) an RRC connection re-establishment procedure; (c) handover; (d) receiving data on the downlink (DL) or uplink (UL) during RRC_CONNECTED when the UL synchronization status is as "unsynchronized"; (e) receiving data on UL during RRC_CONNECTED when there are no physical uplink control channel (PUCCH) resources available for scheduling request (SR); (f) SR failure; (g) RRC request on synchronous reconfiguration; (h) transition from RRC_INACTIVE; (i) establishing (or setting) time alignment when adding a secondary cell (SCell); (j) requesting other system information (which may sometimes be referred to as remaining and other system information in NR mobile networks) or system information (SI) messages; (k) recovery from beam failure. In some embodiments, with (based on, using) the "RACH type selection factor" configured for the trigger, the UE may first determine the trigger and then use the corresponding "RACH type selection factor" to determine which random access procedure (e.g., , 2-way random access procedure or 4-way random access procedure) must be selected.

In the RACH Type Selection Factor Configuration Alternative 6, the RACH Type Selection Factor may be configured for services with different Quality of Service (QoS) requirements, or for a different logical channel or a different group of logical channels. For each service type with different QoS requirement, logical channel or group of logical channels, a "RACH type selection factor" can be configured. Then, according to (based on, using) the QoS requirement, the logical channel or logical channel group from which data is retrieved for transmission, the UE uses the corresponding "RACH type selection factor" to determine which random access procedure (e.g., 2 -step random access procedure or 4-step random access procedure) must be selected.

In Alternative 7 configuration of the RACH type selection coefficient, the RACH type selection coefficient may be configured for each cell. With (based on, using) the "RACH type selection factor" configured for each cell, the UE can first determine the cell, and then use the corresponding "RACH type selection factor" to determine which random access procedure (for example, 2 -step random access procedure or 4-step random access procedure) must be selected.

In Alternative 8 configuration of the RACH type selection coefficient, the RACH type selection coefficient may be configured for each portion of the bandwidth (BWP). With (based on, using) the "RACH type selection factor" configured for each BWP, the UE can first determine the BWP, and then use the corresponding "RACH type selection factor" to determine which random access procedure (for example, 2 -step random access procedure or 4-step random access procedure) must be selected.

In some embodiments, a combination of the aforementioned alternatives may be considered or implemented to configure the RACH type selection factor. For example, for each cell or BWP, different RACH type selection coefficients can be configured for different access category, access ID, UAC-BarringInfoSet, trigger or service type, and so on.

In some embodiments, in relation to the aforementioned alternative options for configuring the selection coefficient of the type Rach, if the "selection coefficient of the type Rach" is absent for the corresponding access/uac-barringinfoset/triger/bvp/bvp/logical requirements/logical The channel/groups of logical channels, the following additional alternative options (A) are used, an additional alternative option 1, where UE uses a 4-storey procedure for arbitrary access; (b) an additional alternative option 2, where the default value (for example, configured by the network or BS, or fixed/specified in the specification) is used for the "selection coefficient of the type RACH"; (C) An additional alternative option 3, where UE uses a 2-storey procedure of arbitrary access.

FIG. 5 is a flow diagram illustrating an exemplary process 500 for an extended random access procedure using a RACH type selection factor, in accordance with some embodiments of the present disclosure. In some embodiments, process 500 may be performed by a wireless communications device (eg, UE 404). In step 502, the wireless communication device receives information indicative of a value from the wireless communication node (eg, BS 402). In some embodiments, the information may be broadcast in system information or via RRC signaling. In some embodiments, the value may correspond to or be associated with a RACH type selection coefficient. In some embodiments, the value may be configured by the wireless node. For example, the value may be configured using alternatives for configuring a RACH type selection factor, as described herein above.

In some embodiments, the value indicated by the information received at step 502 may be configured based on the access category. In some embodiments, the value may be configured based on the UAC-BarringInfoSet. In some embodiments, the value may be configured based on the access identifier. In some embodiments, the value may be configured based on the PLMN. In some embodiments, the value may be configured based on one or more triggers or trigger events of a 4-way random access procedure or a 2-way random access procedure for accessing a wireless node. In some embodiments, the value may be configured based on the QoS requirement. In some embodiments, the implementation of the set of values may be respectively configured based on the set of logical channels or groups of logical channels. In some embodiments, the value may be configured based on the cell in which the wireless communication device resides. In some embodiments, the value may be configured based on the BWP.

Referring again to FIG. 5, at step 504, the wireless communication device may compare the randomly generated value with the value received from the wireless node to determine if the randomly generated value satisfies that value. In some embodiments, the wireless communication device may generate the random number as a randomly generated value. In other embodiments, the randomly generated value may be generated by another device and transmitted to the wireless communication device. In some embodiments, the randomized value may be in the range greater than or equal to 0 and less than 1 (0 ≤ randomized value < 1). In other embodiments, the randomly generated value may be in other ranges.

In some embodiments, in response to determining that the randomly generated value matches the value (e.g., the randomly generated value is less than, or less than or equal to, or greater than, or greater than or equal to the value), at step 504, the process 500 proceeds to step 506. Otherwise, process 500 proceeds to block 508.

In step 506, the wireless communication device selects a 2-way random access procedure to access the wireless node. At step 508, the wireless communication device selects a 4-way random access procedure to access the wireless node. If 2-way random access procedure is selected at block 506, process 500 may proceed to block 510. If 4-way random access procedure is selected at block 508, process 500 may proceed to block 512.

At step 510, the wireless communication device transmits a first message to access the wireless node. The content of the first message transmitted at step 510 may be based on the selection of the 2-way random access procedure. In some embodiments, the content of the first message may include a random access preamble and a payload when (in response) a 2-way random access procedure is selected. In some embodiments, the payload may be optional. In some implementations, the preamble may be optional.

At step 512, the wireless communication device transmits a first message to access the wireless node. The content of the first message transmitted at step 512 may be based on the selection of a 4-way random access procedure. In some embodiments, the content of the first message may include a random access preamble when (in response) a 4-way random access procedure is selected.

In some embodiments, the implementation of the wireless node (eg, BS 402) may send to the wireless device (eg, UE 404) information indicating the value. In some embodiments, the value may correspond to or be associated with a RACH type selection factor. In some embodiments, the value may be configured by the wireless node. For example, the value may be configured using alternatives for configuring a RACH type selection factor, as described herein above. In some embodiments, the implementation of the wireless node may receive, from the wireless device, the first message to access the wireless node. In some embodiments, the first message may include a random access preamble when a 4-round random access procedure is selected (eg, by a wireless communication device). In some embodiments, the first message may include a random access preamble and payload when a 2-way random access procedure is selected (eg, by a wireless communication device). In some embodiments, the payload may be optional. In some implementations, the preamble may be optional. In some embodiments, the wireless node may send a second message in response to the first message.

FIG. 6 is a flowchart illustrating an exemplary process 600 for an extended random access procedure using a RACH type selection factor, in accordance with some embodiments of the present disclosure. In some embodiments, process 600 may be performed by a wireless communications device (eg, UE 404). In step 602, the wireless communication device receives information indicative of a plurality of values from a wireless communication node (eg, BS 402). In some embodiments, the information may be broadcast in system information or via RRC signaling. In some embodiments, the implementation of the set of values, respectively, corresponds to the set of parameters. In some embodiments, the parameter set may be an access control parameter set, such as an access category set, a UAC-BarringInfoSets set, or an access identifier set. In some embodiments, the parameter set may be a non-access control parameter set, such as a PLMN set, a random access procedure trigger or event set, a QoS requirement set, a logical channel or logical channel group set, a cell ID set, or a BWP set. In some embodiments, a plurality of values may be configured by the wireless node. For example, a plurality of values may be configured using alternatives for configuring a RACH type selection factor, as described herein above.

In some embodiments, the set of values received at block 602 may be appropriately configured based on the set of access categories. In some embodiments, the implementation of the set of values may be respectively configured based on the set of UAC-BarringInfoSets. In some embodiments, the implementation of the set of values may be respectively configured based on the set of access identifiers. In some embodiments, a plurality of values may be respectively configured based on a plurality of PLMNs. In some embodiments, the set of values may be respectively configured based on the set of triggers or trigger events of a 4-way random access procedure or a 2-way random access procedure for accessing a wireless node. In some embodiments, the implementation of the set of values may be respectively configured based on the set of QoS requirements. In some embodiments, the implementation of the set of values may be respectively configured based on the set of logical channels or groups of logical channels. In some embodiments, the implementation of the set of values may be respectively configured based on the set of cells. In some embodiments, the implementation of the set of values may be respectively configured based on the set of BWP.

As an example, when the parameter set is a plurality of access categories (i.e., when the "RACH type selection factor" for each access category), the wireless node may configure factor 1 for access category 1, factor 2 for access category 2, factor 3 for access category 3, etc. Continuing with this example, the wireless communication device may then determine or decide on the access category, generate a randomly generated value, and compare the randomly generated value with an appropriate coefficient. For example, if the access category is category 2, the coefficient to be compared is coefficient 2.

Referring again to FIG. 6, in step 604, the wireless communication device selects one parameter from a plurality of parameters. In the above example, when the parameter set is a plurality of access categories, the wireless communication device may select one category from the plurality of access categories. At 606, the wireless communication device may compare the randomly generated value with a value selected from the plurality of values to determine if the randomly generated value satisfies that value. In some embodiments, a value is selected or determined from a plurality of values in accordance with the selected parameter in step 604. In some embodiments, the wireless communication device may generate a random number as the randomly generated value. In other embodiments, the randomly generated value may be generated by another device and transmitted to the wireless communication device. In some embodiments, the randomized value may be in the range greater than or equal to 0 and less than 1 (0 ≤ randomized value <1). In other embodiments, the randomly generated value may be in other ranges.

In some embodiments, in response to determining that the randomly generated value satisfies a value selected from a plurality of values (e.g., the randomly generated value is less than, or less than or equal to, or greater than, or greater than or equal to a value) at 606, the process 600 proceeds to block 608. Otherwise, process 600 proceeds to block 610.

At 608, the wireless communication device selects a 2-way random access procedure to access the wireless node. At step 610, the wireless communication device selects a 4-way random access procedure to access the wireless node. If 2-way random access is selected at 608, process 600 may proceed to 612. If 4-way random access is selected at 610, process 500 may proceed to 614.

At 612, the wireless communication device transmits a first message for accessing the wireless node. The content of the first message transmitted at step 612 may be based on the selection of the 2-way random access procedure. In some embodiments, the content of the first message may include a random access preamble and a payload in the event that (in response) a 2-way random access procedure is selected. In some embodiments, the payload may be optional. In some implementations, the preamble may be optional.

At 614, the wireless communication device transmits a first message for accessing the wireless node. The content of the first message transmitted at 614 may be based on the selection of the 4-round random access procedure. In some embodiments, the content of the first message may include a random access preamble when (in response) a 4-way random access procedure is selected.

In some embodiments, the wireless node (eg, BS 402) may send to the wireless device (eg, UE 404) information indicating a plurality of values. In some embodiments, the implementation of the set of values may, respectively, correspond to the set of parameters. In some embodiments, the implementation of the set of values, respectively, corresponds to the set of parameters. In some embodiments, the parameter set may be an access control parameter set, such as an access category set, a UAC-BarringInfoSets set, or an access identifier set. In some embodiments, the parameter set may be a non-access control parameter set, such as a PLMN set, a random access procedure trigger or event set, a QoS requirement set, a logical channel set, a logical channel group set, a cell ID set, or a BWP set. . In some embodiments, a plurality of values may be configured by the wireless node. For example, a plurality of values may be configured using alternatives for configuring a RACH type selection factor, as described herein above.

In some embodiments, the implementation of the wireless node may receive, from the wireless device, the first message to access the wireless node. In some embodiments, the first message may include a random access preamble when a 4-round random access procedure is selected (eg, by a wireless communication device). In some embodiments, the first message may include a random access preamble and payload when a 2-way random access procedure is selected (eg, by a wireless communication device). In some embodiments, the payload may be optional. In some implementations, the preamble may be optional. In some embodiments, the wireless node may send a second message in response to the first message.

ALT 2: Solution based on "RACH type selection timer"

In some embodiments, a "RACH Type Selection Timer" based decision may be considered or implemented for RACH type selection. In some embodiments, during the operation of each timer, the corresponding UE (eg, UE 404) is not allowed to initiate the 2-way random access procedure, regardless of whether the condition for selecting the 2-way random access procedure is met, if configured. On the other hand, when the timer expires or stops, the UE may select the 2-way random access procedure or the 4-way random access procedure, or perform RACH type selection if other type selection threshold(s) is configured.

In some embodiments, during the operation of each timer, the corresponding UE (e.g., UE 404) is only allowed to initiate a 2-way random access procedure, or is allowed to initiate a 2-way random access procedure, provided that the condition for selecting the 2-way random access procedure is met if it is configured. On the other hand, when the timer expires or stops, the UE may only perform the 4-round RACH.

In some embodiments, one or more timers may be configured with the same or different run time durations. In some embodiments, the duration of the timer may be configured using the following alternatives or options. In a first alternative, the timer may be directly configured by the network or BS and may be broadcast in system information or signaled with Radio Resource Control (RRC) signaling. In a second alternative, the default timer duration may be configured or predetermined (set), and scaling factors may be used to configure the timer duration. If there is no scaling factor, the default duration is used.

In some embodiments, regarding the start of the timer, the "RACH Type Select Timer On Indicator" may be used to control a configurable timer. In some embodiments, the "RACH Type Select Timer On Indicator" may be represented as a single bit if a unified timer is configured, or may be a bit string if multiple timers are configured. In some embodiments, the "RACH Type Selection Timer Enable Indicator" having a value of "1" means that the timer has started and "0" means that the timer has stopped. In other embodiments, complex "RACH Type Selection Timer On Indicator" values or formats may be used. In some embodiments, the "RACH Type Selection Timer On Indicator" may be delivered or transmitted to the UE using system information or RRC signaling, or included in the RA or Msg 2 response. In some embodiments, the UE may receive the "Type Selection Timer On Indicator RACH", which can activate the timer. In some embodiments, the timer may start after the first transmission Msg1 of the 2-round RACH (or after a certain period of time) or after the first transmission of Msg1 of the 4-round RACH (or after a certain period of time).

In some embodiments, the timer configuration may be broadcast in system information or signaled with RRC signaling. In some embodiments, the following alternatives or options may be considered or implemented for RACH type selection timer configuration.

In Alternative 1 RACH Type Selection Timer Configuration, a timer may be configured for each access category. With (based on, using) a timer configured for each access identifier, the UE may first determine the access category and then use the corresponding RACH type selection timer to determine which random access procedure (e.g., 2-way random access procedure or 4-step random access procedure (random access procedure) must be selected.

In Alternative 2 RACH type selection timer configuration, a timer may be configured for each UAC-BarringInfoSet. With (based on, using) the UAC-BarringInfoSet configured for each timer, the UE may first determine the UAC-BarringInfoSet, and then use the corresponding RACH type selection timer to determine which random access procedure (e.g., 2-way procedure random access or 4-step random access procedure) must be selected.

In Alternative 3 RACH Type Selection Timer Configuration, a timer may be configured for each access ID. With (based on, using) a timer configured for each access identifier, the UE may first determine the access identifier and then use the corresponding RACH type selection timer to determine which random access procedure (e.g., 2-way random access procedure or 4-step random access procedure) must be selected.

In Alternative 4 RACH Type Selection Timer Configuration, a timer may be configured for each PLMN. With (based on, using) a timer configured for each PLMN, the UE may first determine the PLMN and then use the corresponding RACH type selection timer to determine which random access procedure (e.g., 2-round random access procedure or 4- staged random access procedure) must be selected.

In the RACH type selection time configuration alternative 5, the timer may be configured to trigger various triggers or trigger events of the RACH procedure. In some embodiments, the following RACH procedure triggers or trigger events may be considered or implemented: (a) initial access from RRC_IDLE; (b) an RRC connection re-establishment procedure; (c) handover; (d) receiving data on the downlink (DL) or uplink (UL) during RRC_CONNECTED when the UL synchronization status is as "unsynchronized"; (e) arrival of UL data during RRC_CONNECTED when there are no available PUCCH resources for a scheduling request (SR); (f) SR failure; (g) RRC request on synchronous reconfiguration; (h) transition from RRC_INACTIVE; (i) establishing (or setting) time alignment when adding SCell; (j) requesting other system information (which may sometimes be referred to as remaining and other system information in NR mobile networks) or system information (SI) messages; (k) recovery from beam failure. In some embodiments, with (based on, using) a timer configured for a particular trigger, the UE may first determine the trigger and then use the appropriate timer to determine which random access procedure (e.g., 2-round random access procedure or 4- staged random access procedure) must be selected.

For example, if timers for various trigger events are configured and the "RACH type selection timer enable indicator" is set to "11111111110" and broadcast in the system information, then the "RACH type selection timer" configured for trigger events other than recovery can be started. beam after failure (BFR). During the operation of each timer, the RACH triggered by the corresponding events can only follow the 4-way random access procedure, except for the RACH triggered by the BFR, where the UE can select 2-way random access procedure or 4-way random access procedure according to one or several specific thresholds, if configured.

In alternative 6 RACH type selection timer configuration, the timer may be configured for services with different QoS requirements, or different logical channels or different groups of logical channels. A timer can be configured for each service type with different QoS requirements/logical channels/logical channel groups. Then, according to (based on, using) the QoS requirements/logical channels/logical channel groups, the UE uses the corresponding "RACH type selection timer" to determine which random access procedure (e.g., 2-way random access procedure or 4-step random access procedure) must be selected.

In Alternative 7 RACH Type Selection Timer Configuration, the timer may be configured for each cell. With (based on, using) a timer configured for each cell, the UE may first determine the cell and then use the corresponding "RACH type selection timer" to determine which random access procedure (e.g., 2-way random access procedure or 4-step random access procedure) must be selected.

In alternative 8 RACH type selection timer configuration, the RACH type selection coefficient may be configured for each BWP. With (based on, using) a timer configured for each BWP, the UE may first determine the BWP, and then use the corresponding "RACH type selection timer" to determine which random access procedure (e.g., 2-way random access procedure or 4-step random access procedure) must be selected.

In some embodiments, a combination of the above alternatives may be considered or implemented to configure the RACH type selection timer. For example, for each cell or BWP, different RACH type selection timers (timer) may be configured for a different access category, access identifier, UAC-BarringInfoSet, trigger or service type, and so on. In some embodiments, if there is no timer configuration, the UE may select the RACH type according to another configured or predefined criteria, if configured.

FIG. 7 is a flow diagram illustrating an exemplary process 700 for an extended random access procedure using a RACH type selection timer, in accordance with some embodiments of the present disclosure. In some embodiments, process 700 may be performed by a wireless communications device (eg, UE 404). In step 702, the wireless communication device receives information indicative of the timer from the wireless communication node (eg, BS 402). In some embodiments, the information may be broadcast in system information or via RRC signaling. In some embodiments, the timer may be or match a RACH type selection timer. In some embodiments, the timer may be configured by the wireless node. For example, the timer may be configured using alternatives for configuring the RACH type selection timer as described herein above.

In some embodiments, the timer (eg, timer duration) indicated by the information received at 702 may be configured based on the access category. In some embodiments, the implementation of the timer (for example, the duration of the timer) can be configured based on the UAC-BarringInfoSet. In some embodiments, the implementation of the timer (eg, the duration of the timer) can be configured based on the access identifier. In some embodiments, the implementation of the timer (eg, the duration of the timer) can be configured based on the PLMN. In some embodiments, a timer (eg, timer duration) may be configured based on one or more triggers or trigger events of a 4-way random access procedure or a 2-way random access procedure for accessing a wireless node. In some embodiments, a timer (eg, timer duration) may be configured based on a QoS/logical channel/logical channel group requirement. In some embodiments, the implementation of the timer (eg, the duration of the timer) may be configured based on the cell in which the wireless device is located. In some embodiments, the implementation of the timer (for example, the duration of the timer) can be configured based on the BWP.

In some embodiments, the duration of the timer may be configured by the communication network or BS and transmitted in system information. In some embodiments, the duration of the timer may be configured by the communication network or base station and signaled using Radio Resource Control (RRC) signaling. In some embodiments, the duration of the timer may be configured based on a scaling factor, and in case there is no scaling factor, a default duration may be used.

In some embodiments, a wireless device can take an inclusion indicator (for example, an indicator of turning on the Rach type Tyer type), which can activate or run the timer. In some embodiments, the inclusion indicator can be transmitted from the wireless unit.

Referring again to FIG. 7, at step 704, the wireless communication device may determine if the timer is in an active state. In some embodiments, the timer is active when the timer is active and the timer is inactive when the timer expires or is stopped. In some embodiments, in response to determining that the timer is active at block 704, process 700 proceeds to block 706, and in response to determining that the timer is inactive at block 704, process 700 proceeds to block 708.

At step 706, the wireless device selects a 4-way random access procedure to access the wireless node in response to determining that the timer is in the active state. At 708, the wireless communication device selects either a 4-way random access procedure or a 2-way random access procedure to access the wireless node in response to determining that the timer is in the idle state. If 4-way random access procedure is selected at block 706, process 700 may proceed to block 710. If either 4-way random access procedure or 2-way random access procedure is selected at block 708, process 700 may proceed to block 712.

At 710, the wireless communication device transmits a first message for accessing the wireless node. The content of the first message transmitted at step 710 may be based on the selection of a 4-way random access procedure. In some embodiments, the content of the first message may include a random access preamble when (in response) a 4-way random access procedure is selected.

At 712, the wireless communication device transmits a first message for accessing the wireless node. The content of the first message transmitted in step 712 may be based on the selection of 4-way random access procedure or 2-way random access procedure in step 708. In some embodiments, the content of the first message may include a random access preamble in the case where at block 708 (in response to this), a 4-round random access procedure is selected. In some embodiments, the content of the first message may include a random access preamble and a payload in the event that a 2-way random access procedure is selected in step 708 (in response to this). In some embodiments, the payload may be optional. In some implementations, the preamble may be optional.

In some embodiments, the implementation of the wireless node (eg, BS 402) may send to the wireless device (eg, UE 404) information indicating the timer. In some embodiments, the timer may be or match a RACH type selection timer. In some embodiments, the timer may be configured by the wireless node. For example, the value may be configured using alternatives for configuring the RACH type selection timer as described herein above. In some embodiments, the implementation of the wireless node may receive, from the wireless device, the first message to access the wireless node. In some embodiments, the first message may include a random access preamble when a 4-round random access procedure is selected (eg, by a wireless communication device). In some embodiments, the first message may include a random access preamble and payload when a 2-way random access procedure is selected (eg, by a wireless communication device). In some embodiments, the payload may be optional. In some implementations, the preamble may be optional. In some embodiments, the wireless node may send a second message in response to the first message.

ALT 3: Deferral indicator based solution

In some embodiments, a backoff indicator may be included in Msg2 (eg, Msg2 in a 2-way random access procedure or a 4-way random access procedure). When the UE receives the backoff indicator, the UE may determine the backoff time according to the backoff indicator. During backoff, the UE is not allowed to repeat the corresponding random access or RACH procedure.

In some embodiments, the backoff indicator may be configured according to the following alternatives: (a) in a first alternative, one backoff indicator may be configured for both RACH types (e.g., 2-way random access procedure and 4-way random access procedure) ; (b) in a second alternative, one backoff indicator is configured for either a 2-way random access procedure or a 4-way random access procedure; (c) in a third alternative, separate backoff indicators may be configured for the 2-way random access procedure and the 4-way random access procedure, respectively, and may be included in Msg2. For example, during the backoff time, the UE cannot initiate the random access procedure for the 2-way random access procedure and the 4-way random access procedure. However, if the backoff time for the 2-way random access procedure is started and the backoff time for the 4-way random access procedure is not started, the UE may only initiate the 4-way random access procedure. Similarly, if the backoff time for the 4-way random access procedure is started and the backoff time for the 2-way random access procedure is not started, the UE may only initiate the 2-way random access procedure.

In some embodiments, a combination of the above alternatives may be considered or implemented. For example, different "RACH type selection factors" may be configured for different trigger events. On top of that, separate backoff times can be configured for the 2-way random access procedure and the 4-way random access procedure. An example is given below assuming that the backoff time for a 2-way random access procedure is longer than the backoff time for a 4-way random access procedure.

In step 1 of the example, the UE determines the RACH type selection coefficient based on the trigger events. The UE then selects the RACH type by comparing the randomly generated number with the RACH type selection coefficient.

In step 2 of the example, the UE selects a RACH resource and transmits Msg1 on the selected RACH resource.

In step 3 of the example, the UE receives Msg2, which includes separate backoff indicators for the 2-way random access procedure and the 4-way random access procedure.

In step 4 of the example, after or when the backoff time for the 4-way random access procedure expires or stops while the backoff time for the 2-way random access procedure has not yet expired, the UE reattempts to perform the 4-way random access procedure. If the UE still has not accessed the BS after the backoff time for the 2-way random access procedure expires or stops, then the UE reattempts to perform the RACH, returning to step 1.

FIG. 8 is a flowchart illustrating an exemplary process 800 for an extended random access procedure with a backoff indicator, in accordance with some embodiments of the present disclosure. In some embodiments, process 800 may be performed by a wireless communications device (eg, UE 404). In step 802, the wireless communication device transmits a first message for accessing the wireless communication node (BS 402). In some embodiments, the content of the first message may be based on the selection of a 4-way random access procedure or a 2-way random access procedure. In some embodiments, selection of a 4-way random access procedure or a 2-way random access procedure may be performed using the processes associated with the "RACH Type Selection Factor" or "RACH Type Selection Timer" as described herein above. In some embodiments, the content of the first message may include a random access preamble in the case where a 4-round random access procedure is selected. If a 2-way random access procedure is selected, the contents of the first message may include a random access preamble and a payload. In some embodiments, the payload may be optional. In some implementations, the preamble may be optional.

In step 804, the wireless communication device receives, from the wireless communication node, in response to the transmission of the first message, a second message indicating the first timer. In some embodiments, the first timer may be a backoff timer or indicator, for example, as described herein above.

At 806, the wireless communication device determines that the first timer is in the idle state. In some embodiments, the wireless communication device may determine if the first timer is active (eg, if the first timer is running). If the first timer is active or running, the wireless communication device is not allowed to repeat the random access or RACH procedure. In such a case, the wireless communication device may wait until the first timer expires or stops. On the other hand, if the first timer is in an inactive state (eg, idle, stops, or terminates when the timer expires), the wireless communication device may repeat the random access procedure.

At 808, in response to determining that the first timer is in the idle state at 806, the wireless device selects either a 4-way random access procedure or a 2-way random access procedure to retransmit the first message. In some embodiments, the first timer may be configured for both a 4-way random access procedure and a 2-way random access procedure. In such a case, the wireless communication device may either retransmit the first message in step 808 using the same random access procedure as in step 802, or select one of the 4-way random access procedure or the 2-way random access procedure according to the process associated with the "RACH Type Selection Coefficient" or "RACH Type Selection Timer" as described herein above.

In some embodiments, the first timer may be configured for one of a 4-way random access procedure or a 2-way random access procedure. In such a case, the wireless communication device may retransmit the first message based on a random access procedure (ie, either a 4-way random access procedure or a 2-way random access procedure) associated with the first timer.

In some embodiments, the first timer may include a first value and a second value. For example, the first value may be configured for a 4-way random access procedure, and the second value may be configured for a 2-way random access procedure. In such a case, the wireless communication device may retransmit the first message using the random access procedure associated with the value indicating the idle timer. If both the first value and the second value indicate idle timers, the wireless device may either retransmit the first message in step 808 using the same random access procedure as in step 802 or select one of the 4-way random access procedure or a 2-way random access procedure according to the process associated with the "RACH Type Selection Coefficient" or "RACH Type Selection Timer" as described herein above.

In some embodiments, a wireless node (eg, BS 402) may receive a first message from a wireless communication device (eg, UE 404). In some embodiments, the content of the first message may be based on the selection of a 4-way random access procedure or a 2-way random access procedure. In some embodiments, the wireless node may send to the wireless device, in response to receiving the first message, a second message indicating the first timer. For example, the first timer may be a backoff time or an indicator. In some embodiments, the implementation of the wireless node may receive the first message transmitted from the wireless device.

D. Content in Msg1 of 2-way RACH

In some embodiments, at least one of the following information may be included in the useful load of MSG1 in a 2-storey procedure of arbitrary access for an implicit or explicit indication of the resource of the temporary area on which the corresponding preamble is transmitted. For example, the information may include: (A) the system frame number (SFN) or the younger meaningful bit (LSB) of the SFN index and the temporary interval index; (b) absolute synchronization, which may contain at least a universal coordinated time corresponding to the SFN border or immediately after the final border of the temporary interval in which the preamble is transmitted; (C) SFN Mod N, where SFN is the radio frame index in which the preamble is transmitted, and n is the frequency of sequential events Rach (RO); and (d) a Random Access Radio Network Temporal Identifier (RA-RNTI) value, which is determined by the RO in which the preamble is transmitted.

E. 2-way RACH Msg1 Transmission Control

In some embodiments, a counter solution may be considered or implemented to control the transmission of Msg1 in a 2-way random access procedure. In some embodiments, the UE may implement a counter at the MAC layer or the physical layer. For each Msg1 transmission, the UE may increase the counter by 1. When the counter exceeds the maximum number of allowed transmission times, the UE may send a RACH error report.

In some embodiments, the implementation of the counter and the maximum number of allowed transmission times can be configured in accordance with the following alternatives.

In a first alternative, one transmission counter and one maximum number of allowed transmission times are defined or configured (eg, Transmax is defined for both 2-hop RACH and 4-hop RACH). For each Msg1 transmission, whether Msg1 of 2-round RACH or 4-round RACH, the counter is incremented by 1. For example, if counter>=(Transmax+1), the UE sends a RACH failure report.

In a second alternative, one transmission counter and a separate maximum number of allowed transmission times are defined or configured for 2-hop RACH and 4-hop RACH (eg, transmax-2step for 2-hop RACH and transmax-4step for 4-hop RACH). In the case where transmax-2step is less than transmax-4step, if the transmission counter value is <= transmax-2step, the UE may initiate 2-round RACH or 4-round RACH; if transmax-2step < transmission counter value <= transmax-4step, the UE is only allowed to initiate a 4-round RACH. Similarly, in the case where transmax-4step < transmax-2step, if the transmission counter value is <= transmax-4step, the UE may initiate a 2-round RACH or a 4-round RACH; if transmax-4step < transmission counter value <= transmax-2step, the UE is allowed to initiate only 2-stage RACH. If the counter value is greater than max{transmax-4step, transmax-2step}, the UE sends a RACH error report.

In a third alternative, separate counters and a separate maximum number of allowable transmission times are defined or configured. You can define or configure one total allowed transmax-total. Separate counters and a separate maximum number of allowable transmission times are supported for 2-step RACH and 4-step RACH (for example, counter-2stepRACH and transmax-2stepRACH are for 2-step RACH (2-stepRACH), while counter-4stepRACH and transmax -4stepRACH are for 4-step RACH (4stepRACH)). The UE is not allowed to select 2-hop RACH or 4-hop RACH if the corresponding counter exceeds the configured corresponding maximum number of allowed transmission times. The UE sends a RACH failure report when (counter-2stepRACH + counter-4stepRACH) exceeds the transmax-total value.

A fourth alternative is to configure a counter to transmit Msg1 (regardless of whether it is Msg1 for 4-hop RACH or Msg1 for 2-hop RACH) and the maximum number of allowable transmission times for 2-hop RACH, such as TransCounter and transmax -2stepRACH. The counter value may be incremented by 1 for each 2-way RACH attempt. After the first 2-stage RACH attempt, the UE may retry the 2-stage RACH only if TransCounter <= transmax-2stepRACH. If Transcounter> = Transmax-2Steprach + 1, then UE is allowed to perform only a 4-stage Rach. In addition to this, a maximum amount of total allowed transmission time can be configured, eg transmax. If TransCounter>=transmax+1, then the UE sends a RACH failure report.

In a fifth alternative, a timer may be introduced to report a RACH failure. The timer is started on the first transmission of Msg1. While the timer is running, the UE may retry the RACH if necessary. The timer stops after the successful completion of the Rach procedure. After the timer, UE sends a rach failure report.

In some embodiments, a combination of one or more of the aforementioned alternatives may also be considered or implemented. For example, you can configure one counter and one transmax; in addition, you can additionally configure the timer. If the conditions for any of the thresholds are met, the UE sends a RACH failure report.

F. RA-RNTI for receiving Msg2 2-way RACH

In some embodiments, after transmitting Msg1, the UE may monitor the corresponding search space with a random access radio network temporary identifier (RA-RNTI) that is calculated based on the RO in which the preamble portion of Msg1 is transmitted.

The RA-RNTI associated with the PRACH case in which the random access preamble is transmitted can be calculated as follows:

RA-RNTI= 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × ul_carrier_id,

where s_id is the index of the first OFDM symbol of the PRACH event (0 ≤ s_id < 14), t_id is the index of the first slot of the PRACH event in the system frame (0 ≤ t_id < 80), f_id is the index of the PRACH event in the frequency domain (0 ≤ f_id < 8 ), and ul_carrier_id is the UL carrier used to transmit the random access preamble (0 is used for a NUL carrier, and 1 for a SUL carrier).

In some embodiments of the present disclosure, the RNTI is 16 bits wide. For cases where the cell size is very large (eg Non-Terrestrial Network (NTN)), or user density is very high (eg Internet of Things (IoT) services), the RNTI capacity can be extended to meet connectivity requirements. Thus, some guidelines may be introduced to allow the use of a long RNTI. For example, a one-bit indicator (eg, with long RNTI enabled) may be introduced. In some embodiments, if the long-RNTI-enabled parameter is set to "1", the long RNTI sequence may be used for scrambling; if the long-RNTI-enabled parameter is set to "0", the traditional RNTI sequence can be used for scrambling. The absence of this indicator is interpreted as long-RNTI-enabled is set to "0" and the normal RNTI sequence may be used for scrambling.

In some embodiments, the indicator may be configured in the following alternatives: (a) in a first alternative, the indicator is included in a Master Information Block (MIB); (b) in a second alternative, the indicator is included in a system information block (SIB); (c) in a third alternative, the indicator is configured for each frequency band (eg, for transmissions using a frequency band configured with "long-RNTI-enabled" set to "1", the long RNTI sequence will be used for scrambling); and (d) in a fourth alternative, an indicator is configured for each PLMN.

In some embodiments, if a long RNTI is used, the RO system frame information in which the Msg1 preamble part is transmitted may be included in the RA-RNTI formula, which may be one of the following: (a) SFN index LSB; (b) SFN_index; (c) SFN_index mod N, where the SFN index is equal to the index of the system frame number where the PRACH event starts, and the PRACH event is the location where the Msg1 preamble part is transmitted. N is the smallest integer greater than or equal to the RAR window size in radio frames (eg, if the RAR window size is 2.5 radio frames, then N is 3).

Below is an example:

RA-RNTI= 1 + s_id + 14*t_id + 14*80*f_id + 14*80*8*ul_carrier_id + 14*80*8*2*frame_id,

where frame_id = SFN_index mod N; N is the smallest integer greater than or equal to the RAR window size in radio frames, which can be written as CIEL (RAR window size in radio frames); and SFN_index is the index of the system frame number where the PRACH event starts, and the PRACH event is the location where the Msg1 preamble part is transmitted.

G. Content and format MSG2 2-Stap Rach

In some embodiments, the following alternatives may be considered or implemented with respect to the content and format of Msg2 of the 2-way random access procedure.

First alternate content and format Msg2

MAC subPDU in Msg2

In some embodiments, a Msg2 MAC Protocol Data Unit (PDU) may include one or more MAC subPDUs and padding as necessary. Each MAC subPDU may include one of the following: (a) a MAC subheader with backoff indicator only; (b) MAC subtitle and successRAR; and (c) MAC subheader and fallback RAR.

MAC subheader format

In some embodiments, the MAC subheader for Msg2 includes the following fields: (a) E: the "Extension" field is a flag indicating whether the MAC subPDU that includes this MAC subheader is the last MAC subPDU in the PDU Mac. In some embodiments, the size of the E field is 1 bit. (b) T: The Type field is a flag indicating the presence of a backoff indicator in the MAC subheader, the presence of a MAC RAR after the MAC subheader, and the type of the corresponding RAR MAC if present (eg, successRAR or fallback RAR). In some embodiments, the size of the T field is 2 bits. (c) BI: The Backoff Indicator field identifies the congestion condition in the cell. In some embodiments, the size of the BI field is 4 bits. (d) R: reserved bit, set to "0" in some embodiments.

In some embodiments, the definition of the 2-bit T field may be implemented as follows: (a) "00": indicates the presence of a backoff indicator field in the subheader (BI); (b) "01": indicates the presence of SUCCESSRAR in Subpdu Mac; (c) "10": indicates the presence of FallBackrar in Subpdu Mac; and d) "11": reserved. In some embodiments, the T field may also be used to indicate the presence of a MAC subPDU for the general resource configuration for sending the MsgB receive ACK, in which case the value "11" of the T field may be used.

It should be noted that the value used for each case listed above is an example, and the mapping between value and case is not limited to the above examples. They are provided for illustrative purposes only and should not be construed as limiting.

In some embodiments, the following two kinds of MAC subheader may be supported in the MAC PDU for the Msg1 response in the 2-way RACH: (a) a MAC subheader with backoff indicator only, which includes four header fields: E/T/R/BI; and (b) a MAC sub-header for successRAR and fallbackRAR, which includes seven header fields: E/T/R/R/R/R/R.

successRAR format

In some embodiments, successRAR has a fixed size and may include the following fields: (a) Contention Resolution ID: This field contains a UL Common Control Channel (CCCH) Service Data Unit (SDU). In some embodiments, if the UL CCCH SDU is longer than 48 bits, this field contains the first 48 bits of the UL CCCH SDU. In some embodiments, the size of the conflict resolution identifier is 48 bits. (b) Timing Advance Command (TAC): The size of this field is the same as the TAC field in the RAR MAC for 4-round RACH. In some embodiments, the size of the timing advance command field is 12 bits. (C) C-RNTI (temporary identifier of the Sota radio network): C-RNTI, selected for UE in Sota. In some embodiments, the C-RNTI field size is 16 bits. (d) R: reserved bit, set to 0 in some embodiments. (e) In some embodiments, the UL grant may be included in successRAR or in some field to carry resource configuration to send ACK to receive MsgB.

fallback RAR format

In some embodiments, the fallbackRAR has a fixed size and may include the following fields: (a) RAPID: The random access preamble identifier field identifies the transmitted random access preamble. In some embodiments, the size of the RAPID field is 6 bits. (b) Time Ahead Command (TAC): The size of this field is the same as the TAC field in the RAR MAC for the 4-round RACH. In some embodiments, the size of the timing advance command field is 12 bits. (c) UL Grant: The size of this field is the same as the UL Grant field in the RAR MAC for 4-round RACH. In some embodiments, the UL grant field size is 27 bits. (d) Temporary C-RNTI: The temporary C-RNTI field indicates the temporary identity that is used by the MAC entity during random access. In some embodiments, the size of the C-RNTI is 16 bits. (e) R: reserved bit, set to 0 in some embodiments.

Second alternative content and format Msg2

MAC subPDU in Msg2

In some embodiments, the Msg2 MAC PDU includes one or more MAC subPDUs and padding as needed. Each MAC subPDU may include one of the following: (a) a MAC subheader with backoff indicator only; and (b) a MAC subheader with RAPID and RAR MAC, where RAR MAC can be used to carry successRAR or fallbackRAR.

MAC subheader format

In some embodiments, the MAC subheader for Msg2 may include the following fields: (a) E: the "Extension" field is a flag indicating whether the MAC subPDU that includes this MAC subheader is the last MAC subPDU in MAC PDU. In some embodiments, the size of the E field is 1 bit. (b) T: The Type field is a flag indicating the presence of a backoff indicator in the MAC subheader and the presence of a MAC RAR after the MAC subheader. In some embodiments, the size of the T field is 1 bit. (c) BI: The Backoff Indicator field indicates the congestion condition in the cell. In some embodiments, the size of the BI field is 4 bits. (d) RAPID: The random access preamble identifier field identifies the transmitted random access preamble. In some embodiments, the size of the RAPID field is 6 bits. (e) R: reserved bit, set to "0" in some embodiments.

In some embodiments, the definition of the 1-bit T field in the MAC subheader may be implemented as follows: (a) "0": indicates the presence of a backoff indicator field in the subheader (BI), and "1": indicates the presence of a MAC RAR in subPDU MAC; or (b) "1": indicates the presence of a backoff indicator field in the subheader (BI), and "0": indicates the presence of a MAC RAR in the MAC subPDU.

In some embodiments, the following two kinds of MAC subheader may be supported in the MAC PDU for the Msg1 response in the 2-way RACH: (a) a MAC subheader with backoff indicator only, which includes four header fields: E/T/R/BI; and (b) a MAC sub-header for successRAR and fallbackRAR, which includes seven header fields: E/T/RAP ID.

Format for RAR MAC

In some embodiments, the RAR MAC has a flexible size and includes one T field and fields for successRAR or fields for fallbackRAR. T: The Type field is a flag indicating whether the RAR MAC includes fields for successRAR or fields for fallbackRAR.

In some embodiments, the 1-bit T field in the RAR MAC is defined as follows: (a) "0": indicates that the RAR MAC includes fields for successRAR, and "1": indicates that the RAR MAC includes fields for fallback RAR; or (b) "1": indicates that the RAR MAC includes fields for successRAR, and "0": indicates that the RAR MAC includes fields for fallbackRAR. In some embodiments, the size of the T field may also be greater than 1 bit. If the T field is greater than 1 bit, in addition to the value used to indicate the RAR MAC, including the field for successRAR or fallbackRAR, another value may be reserved for future use or may be used for other purposes.

In some embodiments, Random Access Successful Response (RAR) fields are included in the following information: (a) Collision Resolution ID: This field contains the UL CCCH SDU. In some embodiments, if the UL CCCH SDU is longer than 48 bits, this field contains the first 48 bits of the UL CCCH SDU. In some embodiments, the size of the conflict resolution identifier is 48 bits. (b) Time Ahead Command (TAC): The size of this field is the same as the TAC field in the RAR MAC for the 4-round RACH. In some embodiments, the size of the timing advance command field is 12 bits. (C) C-RNTI: C-RNTI, selected for UE in Sota. In some embodiments, the C-RNTI field size is 16 bits. (d) R: reserved bit set to 0 in some embodiments. In some embodiments, the UL grant may be included in successRAR or in some field to carry resource configuration to send ACK to receive MsgB.

In some embodiments, the fallbackRAR fields are included in the following information: (a) time advance command (TAC): same as the TAC field in the MAC RAR for 4-round RACH. In some embodiments, the size of the timing advance command field is 12 bits. (b) UL Grant: The size of this field is the same as the UL Grant field in the MAC RAR for 4-way RACH. In some embodiments, the size of the UL grant field is 27 bits. (c) Temporary C-RNTI: The temporary C-RNTI field indicates the temporary identity that is used by the MAC entity during random access. In some embodiments, the size of the C-RNTI is 16 bits. (D) R: Reserve bit established in some embodiments of 0.

H. ACK Resource Configuration for Msg2 2-round RACH

In some embodiments for both Decision 1 and Decision 2 (Alt 1 and Alt 2 below), acknowledgment (ACK) resource information may also be included in Msg2. With the ACK resource information included, the UE determines a resource to send an ACK for Msg2. In some embodiments, the following decisions may be ACK resource configuration decisions: (a) Alternative 1: separate MAC subPDU for the shared resource and explicit configuration of the UE-specific resource in another separate MAC subPDU; (b) Alternative 2: a separate MAC subPDU for a shared resource and an implicit configuration of a UE-specific resource in another separate MAC subPDU; and (c) Alternative 3: UE specific ACK resource as part of successRAR.

In some embodiments, the share configuration, or part of the share configuration, may also be included in the DCI that is used to schedule the MsgB. In some embodiments, the MsgB receive ACK may be sent on PUCCH, PUSCH, or some other physical channel specifically designed for feedback.

In some embodiments, for Alternative 1 and Alternative 2, the common MAC subPDU may be a time and/or frequency and/or code domain resource that may be used by multiple UEs for which a corresponding successful RAR can be found in the same Msg2 . In some embodiments, a code domain resource refers to a code or sequence to be used in transmitting an ACK of receiving an MsgB, including generating an ACK signal.

In some embodiments for Alternative 1, some UE-specific resource configuration may be explicitly included in another separate MAC subPDU. In some embodiments, the explicit configuration resource may be at least one of the following: (a) a code domain resource that may be used by the UE when transmitting the ACK, or some parameters that may be used to calculate or obtain a code domain resource to be used by the UE ; (b) a frequency domain resource that can be used by the UE when transmitting an ACK, or some parameters that can be used to calculate or obtain a frequency domain resource that should be used by the UE; (c) a time domain resource that can be used by the UE when transmitting an ACK, or some parameters that can be used to calculate or obtain a time domain resource that should be used by the UE; and (d) a resource index configured in the shared MAC subPDU for the shared resource, where the resource pool may be configured as a shared resource. For example, the shared resource pool indicates that codes X to Y are reserved for ACK transmission, and in a UE-specific resource configuration, an index can be used to indicate that the nth code should be used for ACK transmission.

In some embodiments for Alternative 2, some kind of UE-specific resource configuration may be implicitly included in another separate MAC subPDU. In some embodiments, the implicit configuration resource may be at least one of the following: (a) the UE obtains a time domain resource based on a RAP identifier (eg, a random access preamble identifier corresponding to the transmitted PREAMBLE_INDEX preamble index), or a sequence of MAC subPDUs in all PDUs MAC in Msg2, or successive MAC RAR sequences in all successful MAC RARs in Msg2, or MAC RAR sequences in all MAC RARs included in Msg2; (b) The UE obtains a frequency domain resource based on the RAP ID (eg, random access preamble ID corresponding to the transmitted PREAMBLE_INDEX), or the MAC subPDU sequence in all MAC PDUs in Msg2, or the success RAR MAC sequence in all successful MAC RARs in Msg2, or sequences of Rar Mac in all Rar Mac included in MSG2; and (c) the UE obtains the code domain resource based on the RAP ID (e.g., random access preamble ID corresponding to the transmitted PREAMBLE_INDEX), or the MAC subPDU sequence in all MAC PDUs in the Msg2 message, or the MAC RAR success sequence in all successful MAC RARs in MSG2 or Rar Mac sequences in all successful Rar Mac included in MSG2.

In some embodiments, for Alternative 1 and Alternative 2 above, the method of combining the common resource and the UE-specific resource may be: (a) Alt1: The ACK resource may include a time/frequency/code domain resource. Some of the resources may be configured as a shared resource and the rest may be configured as a UE-specific resource. For example, a common resource may include a resource in the frequency and time domain, and a UE-specific resource may include a resource in the code domain. Alternatively, the shared resource may include a resource in the time domain, and the UE-specific resource may include a resource in the code domain and the frequency domain. (b) Alt2: The shared resource may include a pool of resources (eg, a list of resources or a range of resources), and the UE-specific resource may include an index to indicate one of the resources in the pool. (c) Alt3: A combination of Alt1 and Alt2. For example, the shared resource may include a time and frequency resource configuration, as well as a range or list of code domain resources. The UE may determine the code domain resource based on some kind of index derived from the UE-specific resource configuration (explicit or implicit) and the range/list specified in the shared resource.

In some embodiments, in order to include a MAC subPDU for a shared ACK resource, a new MAC subPDU must be supported that includes a MAC subheader and ACK resources. In some embodiments, the definition of the 2-bit T field in the MAC subheader may be implemented as follows: (a) "00": indicates the presence of a backoff indicator field in the subheader (BI); (b) "01": indicates the presence of successRAR in the MAC subPDU; (c) "10": indicates the presence of FallBackrar in Subpdu Mac; and (D) "11": indicates the availability of ACK resource in Subpdu Mac.

It should be noted that the value used for each case listed above is an example, and the mapping between value and case is not limited to the above examples. They are provided for illustrative purposes only and should not be construed as limiting.

While various embodiments of the present solution have been described above, it should be noted that they have been presented by way of example only and not as a limitation. Likewise, various diagrams may depict an exemplary architecture or configuration that is provided to enable those skilled in the art to understand the exemplary features and functions of the present solution. However, those skilled in the art will appreciate that the solution is not limited to the illustrated example architectures or configurations, but may be implemented using a variety of alternative architectures and configurations. In addition, as will be understood by those skilled in the art, one or more features of one embodiment may be combined with one or more features of another embodiment described herein. Thus, the breadth and scope of the present disclosure should not be limited by any of the illustrative embodiments described above.

It is also understood that any reference to an element in this document using designations such as "first", "second" and so on, as a rule, does not limit the number or order of these elements. Rather, these designations may be used herein as a convenient means of distinguishing between two or more elements or instances of an element. Thus, referring to the first and second elements does not mean that only two elements can be used, or that the first element must in any way precede the second element.

In addition, one of ordinary skill in the art will appreciate that information and signals may be represented using any/any of a variety of different technologies and methods. For example, data, instructions, commands, information, signals, bits, and symbols, such as may be referred to in the above description, may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof. .

One of ordinary skill in the art will further appreciate that any of the various illustrative logical blocks, modules, processors, means, circuits, methods, and functions described in connection with the aspects disclosed herein may be implemented in electronic hardware (e.g., a digital implementation, analog implementation, or a combination thereof), firmware, various forms of program or design code, including instructions (which for convenience may be referred to in this document as "software" or "software module"), or any combination of these methods. To clearly illustrate this interchangeability of hardware, firmware, and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware, firmware, or software, or a combination of these methods, depends on the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in a variety of ways for each particular application, but such implementation decisions do not cause a departure from the scope of this disclosure.

In addition, one of ordinary skill in the art will appreciate that the various illustrative logical blocks, modules, devices, components, and circuits described herein may be implemented or implemented by an integrated circuit (IC), which may include a common processor destination, digital signal processor (DSP), application specific integrated circuit (ASIC), field programmable gate array (FPGA), or other programmable logic device, or any combination thereof. The logic blocks, modules, and circuits may further include antennas and/or transceivers for communicating with various components on a network or within a device. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, 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 suitable configuration to perform the functions described herein.

Where the functions are implemented in software, they may be stored as one or more instructions or code on a computer-readable storage medium. Thus, the steps of a method or algorithm disclosed herein may be implemented in software stored on a computer-readable storage medium. Computer-readable media includes both computer storage media and communication media, including any media that can be included to transfer a computer program or code from one place to another. A storage media can be any available storage media that can be accessed by a computer. By way of example, and not limitation, such computer-readable storage media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage device, magnetic disk storage device or other magnetic storage devices, or any other storage medium. , which can be used to store desired program code in the form of instructions or data structures that can be accessed by a computer.

As used herein, the term "module" refers to software, firmware, hardware, and any combination of these elements to perform the associated functions described in this document. In addition, for purposes of discussion, the various modules are described as separate modules; however, as will be apparent to one of ordinary skill in the art, two or more modules may be combined to form a single module that performs their associated functions according to embodiments of the present solution.

In addition, memory or other storage device as well as communication components may be used in embodiments of the present solution. It should be noted that, for the sake of clarity, in the above description, embodiments of the present solution have been described with reference to various functional blocks and processors. However, it will be apparent that any suitable distribution of functionality between different functional blocks, processing logic elements, or domains can be used without prejudice to the present solution. For example, functionality shown to be performed by separate processing logic elements or controllers may be performed by the same processing logic element or controller. Thus, references to specific functional blocks are only references to appropriate means to provide the described functionality, and do not indicate a strict logical or physical structure or organization.

Various modifications to the implementations described in this disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other implementations without departing from the scope of this disclosure. Thus, the disclosure is not intended to be limited to the implementations shown herein, but is to be accorded the broadest scope consistent with the novel features and principles disclosed herein as set forth in the following claims.

Claims (66)

1. A way of arbitrary access containing: transmitting by the wireless communication device a first message including a header and a payload to the network; the wireless communication device receiving a second message from the network in response to the first message, where the second message is a MAC PDU that includes one or more MAC subPDUs, where each MAC subPDU of the one or more MAC subPDUs includes at least one of the following: (a) a first MAC subheader with a backoff indicator only (Backoff Indicator), (b) a second MAC subheader and a SuccessRAR, or (c) a third MAC subheader and a fallback RAR. 2. The method of claim 1, wherein at least one of the first MAC subheader, the second MAC subheader, or the third MAC subheader includes at least one of the following: (a) an extension field indicating whether the subPDU is a MAC, which includes a MAC subheader, the last MAC subPDU in the MAC PDU, (b) a type field indicating the presence of a backoff indicator in the MAC subheader, the presence of a MAC RAR after the MAC subheader, and the type of the corresponding MAC RAR if present, (c) an indicator field a backoff that identifies an congestion condition in the cell, and (d) a reserved bit. 3. The method of claim 2, wherein the type field contains two bits, when set to "00", the type field indicates the presence of a backoff indicator field in the subheader, and when set to "01", the type field indicates the presence of SuccessRAR in the MAC subPDU. 4. The method according to claim 1, wherein SuccessRAR has a fixed size and contains: conflict resolution ID, timing advance command (TAC), Cell Radio Network Temporary Identifier (C-RNTI), spare bit and an acknowledgment resource configuration for transmitting an acknowledgment of receipt of the second message. 5. The method of claim 1, wherein the backup RAR has a fixed size and contains: Temporary False Command (TAC), uplink grant (UL), Cell Radio Network Temporary Identifier (C-RNTI) and spare bit. 6. The method of claim 4, wherein the acknowledgment resource configuration comprises: code area resource information, frequency domain resource information and time domain resource information. 7. The method of claim 4, further comprising transmitting an acknowledgment of receipt of the second message on a physical uplink control channel (PUCCH). 8. The method of claim 1, wherein the wireless communication device implements a counter and is configured with a first maximum number and a second maximum number, wherein the first maximum number indicates a maximum allowable number of transmission times for the first message when transmitted in a 2-way random access (RACH) procedure. ), and the second maximum number indicates the total maximum allowed number of transmission times for the first message when transmitted on the 2-way RACH or 4-way RACH. 9. The method of claim 8, further comprising: incrementing the counter by 1 for each 2-way RACH attempt to transmit the first message; And performing another 2-round RACH attempt if the counter value is less than or equal to the first maximum number; or performing a 4-round RACH attempt if the counter value is greater than or equal to the first maximum number + 1. 10. The method of claim 9, further comprising: increment counter by 1 for each 4-round RACH attempt; And transmitting a RACH failure report in response to determining that the counter value is equal to the second maximum number + 1. 11. A wireless communication device, comprising: CPU; And a memory that stores executable instructions, wherein the executable instructions, when executed by the processor, instruct the processor to: transmit a first message including a header and a payload to the network; And receive a second message from the network in response to the first message, where the second message is a MAC PDU that includes one or more MAC subPDUs, where each MAC subPDU of the one or more MAC subPDUs includes at least one of the following: (a) a first MAC subheader with a backoff indicator only, (b) second MAC subheader and SuccessRAR or (c) third MAC subheader and fallback RAR. 12. The wireless communications apparatus of claim 11, wherein at least one of the first MAC subheader, the second MAC subheader, or the third MAC subheader includes at least one of the following: (a) an extension field indicating whether the subPDU is MAC that includes the MAC subheader, the last MAC subPDU in the MAC PDU, (b) a type field indicating the presence of a backoff indicator in the MAC subheader, the presence of a MAC RAR after the MAC subheader, and the type of the corresponding RAR MAC, if present, (c) a backoff indicator field identifying the congestion condition in the cell, and (d) a reserved bit. 13. The wireless communications device of claim 12, wherein the type field contains two bits, when set to "00", the type field indicates the presence of a backoff indicator field in the subheader, and when set to "01", the type field indicates the presence of SuccessRAR in the MAC subPDU. 14. The wireless communications device of claim 11, wherein the SuccessRAR has a fixed size and comprises: conflict resolution ID, timing advance command (TAC), Cell Radio Network Temporary Identifier (C-RNTI), spare bit and an acknowledgment resource configuration for transmitting an acknowledgment of receipt of the second message. 15. The wireless communications apparatus of claim 11, wherein the standby RAR has a fixed size and contains: timing advance command (TAC), uplink grant (UL), Cell Radio Network Temporary Identifier (C-RNTI) and spare bit. 16. The wireless communications device of claim 14, wherein the acknowledgment resource configuration comprises: code area resource information, frequency domain resource information and time domain resource information. 17. The wireless communications apparatus of claim 14, wherein the executable instructions, when executed by the processor, further cause the processor to transmit an acknowledgment of receipt of the second message on a physical uplink control channel (PUCCH). 18. The wireless communication apparatus of claim 11, wherein the wireless communication implements a counter and is configured with a first maximum number and a second maximum number, the first maximum number defining the maximum allowable number of transmission times for the first message when transmitted in a 2-way random access procedure ( RACH), and the second maximum number indicates the total maximum allowed number of transmission times for the first message when transmitted on a 2-way RACH or a 4-way RACH. 19. The wireless communications device of claim 18, wherein the executable instructions, when executed by the processor, further cause the processor to: increment the counter value by 1 for each 2-way RACH attempt to transmit the first message; And perform another 2-step RACH attempt if the counter value is less than or equal to the first maximum number; or perform a 4-way RACH attempt if the counter value is greater than or equal to the first maximum number + 1. 20. The wireless communication device of claim 18, wherein the executable instructions, when executed by the processor, further cause the processor to: increment counter by 1 for each 4-round RACH attempt; And send a RACH error report in response to determining that the counter value is equal to the second maximum number + 1.

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