Blind random access response physical downlink shared channel detection

Abstract

Example embodiments of the present invention provide at least one method and apparatus to perform a predetermined link identifying, by a user equipment of a communication network, at least one physical random access channel occasion of a random access channel procedure for at least one random access response physical downlink shared channel candidate based on determined information; determining, based on the identification, at least one random access response physical downlink shared channel candidate having different time or frequency configurations; blind decoding the at least one random access response physical downlink shared channel candidate based on the determination; and for the at least one random access response physical downlink shared channel candidate, determining a resource of the at least one random access response physical downlink shared channel candidate for a random access response to a random access channel transmission, determining a resource of the at least one random access response physical downlink shared channel candidate is performed without decoding a physical downlink control channel associated with the random access response physical downlink shared channel candidate. Furthermore, to perform transmitting, by a network node of the communication network to the user equipment, information of a configuration map comprising a mapping between at least one random access response occasion and one physical random access channel occasion, wherein the information identifies a predetermined link of at least one physical random access channel occasion of a random access channel procedure for at least one random access response physical downlink shared channel candidate; receiving a preamble index for the random access procedure on a random access channel occasion based on the information; and transmitting a random access response for the preamble index based on the receiving, the random access response indicating that the random access procedure is successful.

Description

Technical Field

[0001] Teachings of exemplary embodiments according to the present invention generally relate to blind decoding of at least one random access response, and more particularly, to blind decoding of at least one random access response without decoding a physical downlink control channel associated with a random access response physical downlink shared channel candidate. Background Art

[0002] This section is intended to provide a background or context for the invention recited in the claims. The description herein may include concepts that could be implemented, but not necessarily concepts that have been previously conceived or implemented. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.

[0003] Certain abbreviations that may be found in the specification and / or drawings are defined herein as follows: CCE: Control Channel Element CCH: Control Channel CRS: Cell Reference Symbol DCI: Downlink Control Information DMRS: Demodulation Reference Symbol DSS: Dynamic Spectrum Sharing HW: Hardware MCS: Modulation and Coding Scheme PDCCH: Physical Downlink Control Channel PDSCH: Physical Downlink Shared Channel PRB: Physical Resource Block RACH: Random Access Channel RAR: Random Access Response RA-RNTI: Random Access-RNTI RE: Resource Element RNTI: Radio Network Temporary Identifier SIB: System Information Block TRP: Transmission Point UE: User Equipment

[0004] Dynamic Spectrum Sharing (DSS) is a technology that enables the parallel use and real-time determination of demand for 5G and LTE in the same frequency band. The available bandwidth is independently divided by the network to use the divided frequencies for mobile communications.

[0005] Note that with all the work done in 3GPP for 5G DSS, for example, the limitations of the PDCCH channel are severe. However, the entire PDCCH blind decoding process is still computationally intensive and still power-hungry, which seems to be one of the reasons for the low adoption of 4G-5G DSS features.

[0006] Example embodiments of the present invention are directed to improving DSS operation to reduce and / or eliminate at least these problems. Summary of the Invention

[0007] This section contains examples of possible implementations and is not meant to be limiting.

[0008] In an exemplary aspect of the present invention, there is an apparatus, such as a user equipment side apparatus, comprising: at least one processor; and at least one non-transitory memory storing instructions, which, when executed by the at least one processor, cause the apparatus to at least: identify, by a user equipment of a communication network, a predetermined link of at least one physical random access channel opportunity for a random access channel procedure for at least one random access response physical downlink shared channel candidate based on determined information; determine, based on the identification, at least one random access response physical downlink shared channel candidate having a different time or frequency configuration; blindly decode the at least one random access response physical downlink shared channel candidate based on the determination; and determine, for the at least one random access response physical downlink shared channel candidate, resources of the at least one random access response physical downlink shared channel candidate for use in a random access response to a random access channel transmission, wherein determining the resources of the at least one random access response physical downlink shared channel candidate is performed without decoding a physical downlink control channel associated with the random access response physical downlink shared channel candidate.

[0009] In another exemplary aspect of the present invention, there is a method comprising: a user equipment of a communication network identifying, based on determined information, a predetermined link of at least one physical random access channel opportunity for a random access channel process for at least one random access response physical downlink shared channel candidate; based on the identification, determining at least one random access response physical downlink shared channel candidate with different time or frequency configurations; based on the determination, blindly decoding the at least one random access response physical downlink shared channel candidate; and, for at least one random access response physical downlink shared channel candidate, determining resources of at least one random access response physical downlink shared channel candidate for a random access response to a random access channel transmission, wherein determining the resources of at least one random access response physical downlink shared channel candidate is performed without decoding a physical downlink control channel associated with the random access response physical downlink shared channel candidate.

[0010] Another example embodiment is an apparatus and a method, comprising the apparatus and method of the preceding paragraphs. wherein the determined information is predetermined by the user equipment or received from a network node of the communication network, wherein the determined information comprises a configuration mapping of a mapping between at least one random access response opportunity and a physical random access channel opportunity, wherein the determined information comprises random access response transmission parameters, wherein a preamble index for a random access procedure is initiated by transmitting an indexed preamble on a random access channel opportunity based on blind decoding; wherein verifying that the random access response is for the transmitted preamble indicates that the received random access response is in response to the transmitted preamble and that the random access response is correct and deemed to be successfully received, wherein determining a resource of at least one random access response physical downlink shared channel candidate to be used by the network node to send the random access response comprises: determining that a successfully decoded physical downlink shared channel candidate carries a valid random access response message based on whether the random access response message indicates the preamble index of the transmitted preamble.

[0011] A non-transitory computer-readable medium storing program code, the program code being executed by at least one processor to perform at least the method as described in the above paragraphs.

[0012] In another example aspect of the present invention, there is an apparatus comprising: a component for identifying, by a user equipment of a communication network, a predetermined link of at least one physical random access channel opportunity for a random access channel process for at least one random access response physical downlink shared channel candidate based on determined information; a component for blindly decoding at least one random access response physical downlink shared channel candidate having at least one different time configuration or frequency configuration based on the identification; blindly decoding at least one random access response physical downlink shared channel candidate based on the determination; and a component for determining, for at least one random access response physical downlink shared channel candidate, resources of at least one random access response physical downlink shared channel candidate for a random access response to a random access channel transmission, wherein determining the resources of at least one random access response physical downlink shared channel candidate is performed without decoding a physical downlink control channel associated with the random access response physical downlink shared channel candidate.

[0013] According to the example embodiments described in the above paragraphs, at least means for identifying, blind decoding, and determining include a network interface, and computer program code stored on a computer-readable medium and executed by at least one processor.

[0014] In another exemplary aspect of the present invention, there is an apparatus, such as a network-side apparatus, comprising: at least one processor; and at least one non-volatile memory storing instructions, which, when executed by the at least one processor, causes the apparatus to at least: send information of a configuration mapping including a mapping between at least one random access response opportunity and a physical random access channel opportunity to a user equipment by a network node of a communication network, wherein the information identifies a predetermined link of at least one physical random access channel opportunity for a random access channel process for at least one random access response physical downlink shared channel candidate; based on the information, receive a preamble for the random access process on the random access channel opportunity; and based on the reception, send a random access response for the preamble index, the random access response indicating that the random access process is successful.

[0015] In another exemplary aspect of the present invention, there is a method comprising: sending, by a network node of a communication network, information of a configuration mapping including a mapping between at least one random access response opportunity and a physical random access channel opportunity to a user equipment, wherein the information identifies a predetermined link of at least one physical random access channel opportunity for a random access channel procedure for at least one random access response physical downlink shared channel candidate; based on the information, receiving a preamble for the random access procedure on the random access channel opportunity; and based on the reception, sending a random access response for the preamble index, the random access response indicating that the random access procedure was successful.

[0016] Another example embodiment is an apparatus and method including the apparatus and method of the previous paragraph 2, wherein the information includes a configuration mapping of a mapping between at least one random access response opportunity and one physical random access channel opportunity.

[0017] A non-transitory computer-readable medium storing program code, the program code being executed by at least one processor to perform at least the method as described in the above paragraphs.

[0018] In another example aspect of the present invention, an apparatus is provided, comprising: a component for sending, by a network node of a communication network, information of a configuration mapping including a mapping between at least one random access response opportunity and a physical random access channel opportunity to a user equipment, wherein the information identifies a predetermined link of at least one physical random access channel opportunity for a random access channel process for at least one random access response physical downlink shared channel candidate; a component for receiving, based on the information, a preamble for the random access process on the random access channel opportunity; and a component for sending, based on the receiving, a random access response for a preamble index, the random access response indicating that the random access process was successful.

[0019] According to the example embodiments described in the above paragraphs, at least the means for sending, identifying and receiving include a network interface, and computer program code stored on a computer readable medium and executed by at least one processor. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and other aspects, features and benefits of various embodiments of the present disclosure will become more apparent from the following detailed description with reference to the accompanying drawings, in which like reference numerals are used to represent similar or equivalent elements. The accompanying drawings are shown to facilitate a better understanding of the embodiments of the present disclosure and are not necessarily drawn to scale, wherein:

[0021] Figure 1 shows a message sequence for a random access response (RAR) blind decoding procedure according to an example embodiment of the present invention;

[0022] Figure 2 shows a user equipment flow chart for a blind decoding process according to an example embodiment of the present invention;

[0023] Figure 3 shows high-level block diagrams of various devices used to perform various aspects of the present invention; and

[0024] Figure 4A and Figure 4B Each shows a method according to an exemplary embodiment of the present invention that can be performed by an apparatus. DETAILED DESCRIPTION

[0025] Example embodiments of the present invention are directed to blindly decoding at least one random access response without decoding a physical downlink control channel associated with a random access response physical downlink shared channel candidate.

[0026] As mentioned above, Dynamic Spectrum Sharing (DSS) is a technology that enables the parallel use and real-time determination of demand for 5G and LTE in the same frequency band. The available bandwidth is independently divided by the network for mobile communications using the divided frequencies.

[0027] DSS (Dynamic Spectrum Sharing): “Spectrum sharing” means that multiple radio access technologies share the same spectrum. In one example, the two radio access technologies sharing the same spectrum are LTE and NR, while in another example, the two radio access technologies sharing the same spectrum are NR and 6G. "Dynamic" means that the channel allocation is not static, but varies in time and / or frequency (e.g., from one subframe / time slot to another), and • DSS is a very important feature for certain (big) operators (eg in the US).

[0028] When deploying 4G-5G Dynamic Spectrum Sharing (DSS), one of the fundamental principles is to minimize the impact on the legacy LTE network. This has led to DSS deployments in low-frequency bands where NR has very limited PDCCH resources. At the time of this application, the standard also addresses this shortcoming with regard to cross-carrier scheduling from SCell to PCell. However, at least for DSS use cases, cross-carrier scheduling is a complex feature and its adoption by the ecosystem seems to be low (it should be noted that cross-carrier scheduling requires separate UE capabilities on top of the carrier aggregation feature).

[0029] At the time of this application, a consensus was reached in the standards submission work item to further help resolve the NRPDCCH bottleneck in DSS deployment. The goals of the work item were stated as follows: Study and, if necessary, specify NR PDCCH reception in symbols utilizing LTE CRS REs. [RAN1]: o Study enabling LTE CRS puncturing of NR PDCCH, including the impact on NR PDCCH DMRS, if there is a performance gain from additional PDCCH resources; A UE is allowed to support and be configured with two overlapping CRS rate matching modes, regardless of whether multiple TRPs are supported or configured [RAN1, RAN2].

[0030] PDCCH basics:

[0031] For example, in addition to scheduling broadcast messages, the PDCCH channel is also used for dynamic scheduling of UEs in UL and DL. The PDCCH as a control channel is an overhead for the system and it should be minimized.

[0032] Typically, the PDCCH is already located in the first 1 to first 3 symbols of the timeslot. In cells with small bandwidth (e.g., 5 MHz), the amount of available PDCCH resources can become a bottleneck for scheduling. As an example, in a DSS configuration between 4G and 5G, typically only one symbol is allocated for the 5G PDCCH. This limits the scheduler to 4 CCEs for scheduling in UL and DL. In this case, if a cell-edge user requires 4 CCEs for UL scheduling, there are no CCEs left for any DL scheduling, so DL PRBs for NR may be wasted in the NR timeslot of the DSS cell.

[0033] Furthermore, it should be considered that many CCH messages, such as SIB, paging, and random access response (RAR) messages, are sent using an aggregation level of at least 4, which is the minimum configuration for the common search space allowed by the 3GPP specifications.

[0034] UE blind decoding process for PDCCH

[0035] A UE is typically configured with time (symbols), frequency resources, and time slots (monitoring occasions) in which a PDCCH containing an UL or DL ​​grant is available to the UE. During each PDCCH monitoring occasion, the UE must perform blind decoding within the defined region where the PDCCH may be transmitted to determine whether something was transmitted. To facilitate blind decoding, the specification provides the UE with hash tables to determine the starting elements for different aggregation levels and limits the number of blind decodes the UE can perform. During the blind decoding process, the UE must derive the location of the PDCCH DMRS, perform channel estimation, and then attempt to decode the data on the associated resource elements based on the possible RNTI it is decoding. Overall, the number of blind decodes a UE requires to get through each monitoring occasion is a trade-off between PDCCH scheduling flexibility and the UE's ability to process PDCCH candidates. The latter is known as the PDCCH blind decoding (BD) budget, and the more BDs a UE needs to support per time unit, the more PDCCH decoding hardware it requires and the more power it consumes searching for potential PDCCH transmissions per time unit.

[0036] From all the work done in 3GPP for 5G DSS, it can be seen that the limitation of PDCCH channel is serious and is one of the (many) reasons that has led to the low adoption of 4G-5G DSS features.

[0037] The entire PDCCH blind decoding process is computationally intensive and, in addition, power-intensive. In fact, a large number of fundamental energy-saving measures from the UE side focus on optimizing the time periods during which the UE can avoid monitoring the PDCCH channel. The PDCCH BD budget supported by the UE must be allocated across the different DCI formats in a way that enables the network to use these formats, leading to a complex optimization problem where the BD budget is always too small from the network's perspective, and too much from the UE's perspective from a hardware and energy efficiency perspective.

[0038] There are certain transmissions, such as random access responses, for which the UE only needs to know a few parameters in order to decode them correctly, however, in order to obtain these parameters the UE must perform the entire blind decoding process of the PDCCH.

[0039] Furthermore, although the specification allows for configurability of parameters associated with the transmission of RAR (or Msg2), these are typically always configured in a static manner in the cell since at this stage of the random access procedure the network has no knowledge of the UE capabilities or radio conditions.

[0040] How to use PDCCH resources more efficiently and improve UE energy saving?

[0041] According to the random access response detection process of the prior art:

[0042] During the random access procedure, the UE selects a preamble index, transmits a preamble on a RACH opportunity, and then attempts to detect DCI format 1_0 scrambled with RA-RNTI during a predetermined time window (ra-Response Window). At a higher level, if the UE detects DCI 1_0 scrambled with the RA-RNTI associated with the RACH opportunity on which the UE sent the preamble, the UE will proceed to decode the PDSCH indicated by that PDCCH opportunity, and the UE will proceed according to the action of the received RAR.

[0043] Example embodiments of the present invention provide a framework by which a UE does not need to perform blind decoding of the PDCCH for the RAR and then decode the PDSCH for the RAR.

[0044] Before describing in detail the exemplary embodiments of the invention herein, reference is made to Figure 3 , which shows a simplified block diagram of various electronic devices that are suitable for use in practicing the example embodiments of this invention.

[0045] Figure 3 A block diagram of one possible and non-limiting exemplary system in which example embodiments may be practiced is shown. Figure 3In the embodiment, user equipment (UE) 10 performs wireless communication with wireless network 1 or network 1, such as Figure 3 As shown. Figure 3 The wireless network 1 or network 1 in the present disclosure may include a communication network, such as a mobile network, for example the mobile network 1 or the first mobile network of the present disclosure. Figure 3 Any reference to the wireless network 1 in the can be considered as a reference to any wireless network as invented herein. Figure 3 The wireless network 1 in the embodiment may also include hardwired features that may be required by the communication network. A UE is a wireless, typically mobile device that can access a wireless network. A UE may be, for example, a mobile phone (also known as a "cellular" phone) and / or a computer with mobile terminal functionality. For example, a UE or mobile terminal may be a portable, pocket-sized device, a handheld device, a computer-embedded device, or a mobile device mounted in a vehicle, and may perform voice signaling and / or data exchanges with the RAN.

[0046] UE 10 includes one or more processors DP 10A, one or more memories MEM 10B, and one or more transceivers TRANS 10D, interconnected via one or more buses. Each of the one or more transceivers TRANS 10D includes a receiver and a transmitter. The one or more buses can be an address bus, a data bus, or a control bus, and can include any interconnection mechanism, such as grouped lines on a motherboard or integrated circuit, optical fibers, or other optical communication devices. The one or more transceivers TRANS 10D can optionally be connected to one or more antennas for communication with network network 12. The one or more memories MEM 10B include computer program code PROG 10C. UE 10 communicates with network network 12 via wireless link 11 or wireless link 16.

[0047] NN 12 (NR / 5G Node B, evolved NB or LTE equipment) is a network node, such as a Figure 3NN 12 provides access to wireless devices, such as UE 10, for communication with a wireless network 1. NN 12 includes one or more processors DP 12A, one or more memories MEM 12B, and one or more transceivers TRANS 12D, interconnected by one or more buses. According to example embodiments, these TRANS 12D may include X2 and / or Xn interfaces for performing example embodiments. Each of the one or more transceivers TRANS 12D includes a receiver and a transmitter. The one or more transceivers TRANS 12D may optionally be connected to one or more antennas for communicating with UE 10 via at least link 11. The one or more memories MEM 12B and computer program code PROG 12C are configured to utilize the one or more processors DP 12A to cause NN 12 to perform one or more operations as described herein. NN 12 may communicate with another gNB or another eNB, such as via link 16. In addition, link 11, link 16 and / or any other link may be wired or wireless or both, and may implement, for example, an X2 or Xn interface. In addition, link 11 and / or link 16 may be connected through other network devices, such as, but not limited to, Figure 3 The NN 12 may include NCE / MME / SGW / UDM / PCF / AMF / SMF 14 devices. The NN 12 may perform functions of an MME (Mobility Management Entity) or an SGW (Serving Gateway), such as user plane functions and / or access management functions for LTE and similar functions for 5G.

[0048] LMF 13 (NR / 5G, Evolved NB or LTE equipment) is a network device such as a Figure 3The LMF 13 is a location management function device (e.g., for NR or LTE Long Term Evolution) that communicates with devices such as the NN 12 and the UE 10. The LMF 13 can be associated with a mobility function device such as an AMF or SMF. Furthermore, the LMF 13 can communicate with devices such as the NN 12 and / or the UE 10 and / or the wireless network 1. The LMF 13 includes one or more processors DP 13A, one or more memories MEM 13B, one or more network interfaces, and one or more transceivers TRANS 13D, interconnected via one or more buses. According to example embodiments, these network interfaces of the LMF 13 may include X2 and / or Xn interfaces for implementing the example embodiments. Each of the one or more transceivers TRANS 13D includes a receiver and a transmitter that can optionally be connected to one or more antennas. The one or more memories MEM 13B include computer program code PROG 13C. For example, the one or more memories MEM 13B and the computer program code PROG 13C are configured to, using the one or more processors DP 13A, cause the LMF 13 to perform one or more operations described herein. The LMF 13 may communicate with another mobility function device and / or an eNB (such as the NN 12 and the UE 10 or any other device or the NCE / MME / SGW / UDM / PCF / AMF / SMF 14) using, for example, the link 11 or the link 16 or another link. Figure 3 The links 16 shown may be used for communication between NN 12 and NN 13. These links may be wired or wireless or both and may implement, for example, an X2 or Xn interface. In addition, as described above, the links 11 and / or 16 may pass through other network devices such as, but not limited to, NCE / MME / SGW devices, such as Figure 3 NCE / MME / SGW / UDM / PCF / AMF / SMF 14.

[0049] Figure 3 The one or more buses of the devices may be an address bus, a data bus, or a control bus, and may include any interconnection mechanism, such as a series of wires on a motherboard or integrated circuit, optical fiber or other optical communication equipment, a wireless channel, etc. For example, one or more transceivers TRANS12D, TRANS13D, and / or TRANS10D may be implemented as a remote radio head (RRH), where other elements of the NN 12 are physically located at a different location than the RRH, and these devices may include one or more buses that may be implemented in part as fiber optic cables to connect the other elements of the NN 12 to the RRH.

[0050] It should be noted that although Figure 3A network node such as NN 12 is shown, but the node may be incorporated into or incorporated into an eNodeB or eNB or gNB such as for LTE and NR and still be configurable to perform the example embodiments.

[0051] It should also be noted that while the description herein indicates that a "cell" performs a function, it should be understood that it is the gNB and / or user equipment and / or mobility management function equipment that form the cell that performs the function. Furthermore, a cell forms part of a gNB, and each gNB can have multiple cells.

[0052] The wireless network 1 or any network it may represent may or may not include NCE / MME / SGW / UDM / PCF / AMF / SMF 14, which may include (NCE) network control element function, MME (Mobility Management Entity) / SGW (Serving Gateway) function, and / or Serving Gateway (SGW), and / or MME (Mobility Management Entity) and / or SGW (Serving Gateway) function, and / or User Data Management Function (UDM), and / or PCF (Policy Control) function, and / or Access and Mobility Management Function (AMF) function, and / or Session Management (SMF) function, and / or Location Management Function (LMF), and / or Authentication Server (AUSF) function, and the AUSF function provides connection to another network (such as a telephone network and / or a data communication network (e.g., the Internet)), and the network is configured to perform any 5G and / or NR operations in addition to or instead of other standard operations at the time of this application. NCE / MME / SGW / UDM / PCF / AMF / SMF / LMF 14 may be configured to perform operations according to any example embodiment of LTE, NR, 5G, and / or any standard-based communication technology implemented or discussed at the time of this application. Additionally, it should be noted that operations performed by NN 12 and / or LMF 13 according to example embodiments may also be performed at NCE / MME / SGW / UDM / PCF / AMF / SMF / LMF 14.

[0053] NCE / MME / SGW / UDM / PCF / AMF / SMF / LMF 14 includes one or more processors DP 14A, one or more memories MEM 14B, and one or more network interfaces (N / W I / Fs) interconnected via one or more buses coupled to link 13 and / or link 16. According to example embodiments, these network interfaces may include X2 and / or Xn interfaces for implementing example embodiments. One or more memories MEM 14B include computer program code PROG 14C. One or more memories MEM 14B and computer program code PROG 14C are configured to utilize one or more processors DP 14A to cause NCE / MME / SGW / UDM / PCF / AMF / SMF / LMF 14 to perform one or more operations that may be required to support operations according to example embodiments.

[0054] It should be noted that the NN 12 and / or LMF 13 and / or UE 10 may be configured (e.g., based on a standard implementation, etc.) to perform the functionality of a location management function (LMF). The LMF functionality may be embodied in any of these network devices or other devices associated with these devices. In addition, the functionality of the LMF (e.g., LMF 13) may be co-located with the UE 10 to communicate with the LMF. Figure 3 The NN 12 and / or LMF 13 are separated for performing operations according to example embodiments as disclosed herein.

[0055] Wireless network 1 can implement network virtualization, which is the process of combining hardware network resources and software network resources and network functions into a single software-based management entity, a virtual network. Network virtualization involves platform virtualization, which is often combined with resource virtualization. Network virtualization is categorized as external, combining many networks or parts of networks into virtual units, or internal, providing network-like functionality to software containers on a single system. Note that the virtualized entities resulting from network virtualization are still implemented at some level using hardware such as processors DP 10, DP 12A, DP 13A, and / or DP 14A and memories MEM 10B, MEM 12B, MEM 13B, and / or MEM 14B, and such virtualized entities also produce technical effects.

[0056] The computer-readable memories MEM 12B, MEM 13B, and MEM 14B may be of any type suitable for the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and removable memory. The computer-readable memories MEM 12B, MEM 13B, and MEM 14B may be components for performing storage functions. As non-limiting examples, the processors DP 10, DP 12A, DP 13A, and DP 14A may be of any type suitable for the local technical environment and may include one or more of a general-purpose computer, a special-purpose computer, a microprocessor, a digital signal processor (DSP), and a processor based on a multi-core processor architecture. The processors DP 10, DP 12A, DP 13A, and DP 14A may be components for performing functions such as controlling the UE 10, NN 12, LMF 13, and other functions described herein.

[0057] In general, various embodiments of any of these devices may include, but are not limited to, cellular telephones (e.g., smart phones), tablet computers, personal digital assistants (PDAs) with wireless communication capabilities, portable computers with wireless communication capabilities, image capture devices (e.g., digital cameras) with wireless communication capabilities, gaming devices with wireless communication capabilities, music storage and playback appliances with wireless communication capabilities, Internet appliances permitting wireless Internet access and browsing, tablet computers with wireless communication capabilities, and portable units or terminals incorporating combinations of such functionality.

[0058] Furthermore, various embodiments of any of these devices may be used with a UE vehicle, a high altitude platform station, or any other such type of node associated with a terrestrial network or any drone type radio or radio in an aircraft or other airborne vehicle or vessel traveling on water, such as a ship.

[0059] Similar to what was described above, example embodiments of the present invention provide a framework by which a UE does not need to perform blind decoding of the PDCCH for a RAR and then decode the PDSCH for the RAR.

[0060] The framework provided is based on the UE performing blind decoding of PDSCH RAR using some predetermined information on how the RAR PDSCH is parameterized. The high-level steps according to an example embodiment of the present invention include: • For example, via RRC or system information, the UE is configured or provided for blind RAR decoding (time / frequency (multi ) configuration, MCS, ...); The UE is configured or provided with a predetermined linkage of PRACH opportunities and a time window for RAR PDSCH candidates; The UE blindly decodes only the PDSCH of different RAR PDSCH candidates (without PDCCH for RARPDSCH) with potentially different time / frequency configurations; When a UE detects a valid PDSCH RAR, the UE verifies its link to the preamble / RACH timing used by the UE based on the indication carried by the RAR. According to an exemplary embodiment of the present invention, the UE must discover that the PDSCH is for RAR via PDSCH decoding. In the prior art, the UE learns this based on the PDCCH. If the verification is successful, the UE proceeds according to the actions of the received RAR.

[0061] Note that the described invention is applicable to both DSS and non-DSS scenarios and for both contention-free or contention-based random access for 4-step RACH and 2-step RACH.

[0062] Note that this mechanism is a challenge in attempting to eliminate common DCI formats sent in the common search space, which complicates dedicated user plane traffic transmission due to the size of the PDCCH BD and having to support different DCI format sizes and the need to multiplex the PDCCH for unicast UEs with common search space common DCI formats (such as PDCCH scheduling RAR).

[0063] It is worth noting that the UE already has the PDSCH decoding HW sized to be able to handle large transport blocks (large number of PDSCH code blocks) per transmission time interval for regular user plane data traffic, whereas the RAR message is very small and therefore the need to blindly decode the RAR multiple times over a transmission time interval does not require any UE HW which does not exist anyway.

[0064] This procedure does not pose any additional security risk, as any UE can monitor RARPDCCH and decode the corresponding PDSCH even based on today's implementation.

[0065] Figure 1 An example of the message sequence of the proposed framework is depicted. In step

[10] , the gNB provides the UE with information used to determine the mapping between RACH opportunities (RA-RNTI) and possible locations of the RAR. This information can be provided, for example, via a system information broadcast message for idle mode UEs or, for example, via a dedicated RRC for the UE in dual connectivity.

[0066] By providing this information, the UE no longer needs a PDCCH grant (DCI) to decode the RAR on the PDSCH, as the information that was previously provided by the PDCCH grant after the RACH preamble was received by the gNB is now provided before the RACH procedure even starts.

[0067] According to 3GPP TS 38.213, only limited information is required to decode the RAR. A DCI format 1_0 is scheduled to provide UE information about, for example, frequency and time domain resources, the modulation and coding scheme employed, and so on. In current technology, this DCI information is scrambled with the RA-RNTI, and the UE will perform blind decoding to decode this information before attempting to decode the PDSCH indicated by the PDCCH. A very similar process is also used for LTE random access.

[0068] exist Figure 1 In step

[20] , the UE selects the preamble index and passes Figure 1 The UE initiates the random access procedure by transmitting the preamble on the RACH opportunity step

[30] . The UE determines the resources where the gNB can send the RAR step

[40] based on the information from step

[10] . Figure 1 In step

[50] , the UE starts a timer that determines the time period during which the gNB can send the RAR. This timer may be provided by the gNB via, for example, a system information message. Figure 1 In step

[60] , the gNB decides to transmit the preamble after detecting the preamble transmitted by the UE. Figure 1 (There may also be several candidate RAR instances with the same timing but separated in frequency to allow for some frequency selectivity in the scheduling decision, in which case there are multiple candidates to flexibly select any one of them to actually transmit the RAR). Figure 1 In step

[10] , the gNB performs the following operations in the resources indicated for the RACH opportunity used by the UE: Figure 1 The UE performs the transmission of the RAR in step

[90] .

[0069] From the UE's perspective, after step

[50] , the UE attempts to decode the PDSCH within the frequency and time (symbol) range associated with its selected RACH opportunity. To do this, the UE needs to perform channel estimation based on the DMRS pattern and then attempt to decode the PDSCH based on the information provided in step

[10] . The RAR is typically transmitted with a robust modulation and coding scheme to enable cell edge users to decode it, however it typically occupies much fewer PRB blocks than the PDCCH and only needs to be attempted to be decoded once for each possible RAR opportunity. This reduces UE complexity and potentially promotes UE energy saving. In response to not correctly decoding the RAR PDSCH in the RAR candidate in steps [70, 80], i.e., the UE performs the blind decoding process but determines that there is no RAR in either of the two candidates, the UE continues to perform blind decoding of the PDSCH. In step

[90] , the UE successfully decodes the RAR sent by the gNB because this is the candidate that the gNB selected to send the RAR (for robustness, the gNB may send the RAR in multiple candidates, but this may not be the desired mode of operation). In step

[100] , the UE verifies that the RAR is actually for the preamble index / RO it sent before declaring the RAR to be successfully received. Figure 1 steps

[110] .

[0070] exist Figure 2 A flowchart for the RAR blind decoding process from the UE perspective is provided in for further explanation. These steps are similar to those explained above.

[0071] Figure 2 FIG. 4 shows a flow chart of a user equipment for a blind decoding process according to an exemplary embodiment of the present invention. Figure 2 As shown in step 10, a configuration is received to map the RAR opportunity to the RACH opportunity. Figure 2 As shown in step 20, a RACH preamble index is selected and transmitted. Figure 2 As shown in step 30, the PDSCH resource to be monitored for RAR is determined, such as Figure 2 As shown in step 50, it is determined whether the PDSCH is successfully decoded. Figure 2 If the result of step 50 is no, then as long as the T_rar timer has not expired, it is determined again whether the PDSCH is successfully decoded. Figure 2 If the step 50 is yes, then Figure 2 As shown in step 60 of the embodiment, it is determined whether the decoded PDSCH corresponds to the RAR associated with the transmitted preamble index. If yes at step 50, then Figure 2 As shown in step 70, the RAR is successfully received. If the answer is no at step 50, then Figure 2As shown in step 80, determine whether T_rar has expired. If the T_rar timer has not expired, return to Figure 2 If T_rar has expired, then as shown in step 90, it is determined that the RACH process has failed.

[0072] Figure 4A and Figure 4B Each shows a method according to an exemplary embodiment of the present invention that can be performed by an apparatus.

[0073] Figure 4A It shows that the device can be used by, for example, but not limited to, Figure 3 The operation performed by the UE 10) device in FIG. Figure 4A As shown in step 410, a user equipment of the communication network identifies a predetermined link of at least one physical random access channel opportunity for a random access channel procedure of at least one random access response physical downlink shared channel candidate based on the determined information. Figure 4A As shown in step 420, based on the identifier, at least one random access response physical downlink shared channel candidate with different time or frequency configuration is determined. Figure 4A As shown in step 425, based on the determination, blind decoding is performed on at least one random access response physical downlink shared channel candidate physical downlink shared channel candidate. Figure 4A As shown in step 430, for at least one random access response physical downlink shared channel candidate, determine the resources of at least one random access response physical downlink shared channel candidate for random access response to random access channel transmission. Then, as Figure 4A As shown in step 440, determining the resources of at least one random access response physical downlink shared channel candidate is performed without decoding a physical downlink control channel associated with the random access response physical downlink shared channel candidate.

[0074] According to the example embodiments described in the above paragraphs, the determined information is predetermined by the user equipment or received from a network node of the communication network.

[0075] According to the example embodiment described in the above paragraphs, the determined information includes a configuration mapping of a mapping between at least one random access response opportunity and one physical random access channel opportunity.

[0076] According to the example embodiment described in the above paragraphs, the determined information includes random access response transmission parameters.

[0077] According to the example embodiments described in the above paragraphs, a preamble index for a random access procedure is initiated by transmitting an indexed preamble on a random access channel opportunity based on blind decoding; and verifying that a random access response is for the transmitted preamble, the verification indicating that the received random access response is in response to the transmitted preamble, and the random access response is correct and is deemed to be successfully received.

[0078] According to the example embodiment described in the above paragraphs, determining resources of at least one random access response physical downlink shared channel candidate to be used by the network node to send a random access response includes: based on whether the random access response message indicates a preamble index of the transmitted preamble, determining that a successfully decoded physical downlink shared channel candidate carries a valid random access response message.

[0079] A stored program code ( Figure 3 PROG 10C) non-transitory computer readable medium ( Figure 3 MEM 10B), the program code is executed by at least one processor ( Figure 3 DP 10A) is executed to perform at least the operations described in the above paragraphs.

[0080] According to an exemplary embodiment of the present invention as described above, there is an apparatus comprising: Figure 3 Users in network 1) (such as Figure 3 UE 10 in the embodiment of the present invention) identifies (one or more transceivers 10D; MEM 10B; PROG 10C; and DP 10A) a predetermined linked component for at least one physical random access channel opportunity of a random access channel procedure for at least one random access response physical downlink shared channel candidate based on the determined information; and is configured to identify (such as Figure 3 One or more transceivers 10D; MEM 10B; PROG 10C; and DP 10A) having at least one random access response physical downlink shared channel candidate with different time or frequency configurations; for performing (such as Figure 3 One or more transceivers 10D; MEM 10B; PROG 10A; and DP 10A) blind decoding (such as Figure 3 one or more transceivers 10D; MEM 10B; PROG 10C; and DP 10A); and a resource for determining at least one random access response physical downlink shared channel candidate is performed without decoding a physical downlink control channel associated with the random access response physical downlink shared channel candidate (e.g., Figure 3Components of one or more transceivers 10D; MEM 10B; PROG 10A; and DP 10A).

[0081] In an exemplary aspect of the invention according to the above paragraphs, wherein at least the means for identifying, blind decoding and monitoring comprises encoding operably controlled by at least one processor [ Figure 3 Computer program executed by DP 10A] Figure 3 PROG10C] in a non-transitory computer readable medium [ Figure 3 MEM 10B].

[0082] Figure 4B It shows that the device can be used by, for example, but not limited to, Figure 3 The operation performed by the device in NC 12). Figure 4A As shown in step 450, the network node of the communication network sends configuration mapping information including mapping between at least one random access response opportunity and a physical random access channel opportunity to the user equipment. Figure 4A As shown in step 460, the information identifies a predetermined link of at least one physical random access channel opportunity of a random access channel procedure for at least one random access response physical downlink shared channel candidate. Figure 4A As shown in step 470, based on this information, a preamble index for the random access procedure is received on a random access channel opportunity. Then, as Figure 4A As shown in step 480, based on the reception, a random access response for the preamble index is sent, where the random access response indicates that the random access procedure is successful.

[0083] According to an exemplary embodiment of the present invention invented above, the information includes a configuration mapping of a mapping between at least one random access response opportunity and one physical random access channel opportunity.

[0084] A stored program code ( Figure 3 PROG 12C) non-transitory computer readable medium ( Figure 3 MEM 12B), the program code is executed by at least one processor ( Figure 3 DP 12A) is executed to perform at least the operations described in the above paragraphs.

[0085] According to an exemplary embodiment of the present invention as described above, there is an apparatus comprising: Figure 3 Network nodes in network 1) (such as Figure 3 ND 12) to the user equipment (such as Figure 3 UE 10 in sends (such as Figure 3One or more transceivers 12D; MEM 12B; PROG 12C; and DP 12A in the figure) includes a component for configuring mapping information between at least one random access response opportunity and a physical random access channel opportunity, wherein the information identifies (the one or more transceivers 12D; MEM 12B; PROG 12C; and DP 12A in the figure) a predetermined link of at least one physical random access channel opportunity for a random access channel procedure of at least one random access response physical downlink shared channel candidate; a component for receiving (the one or more transceivers 12D; MEM 12B; PROG 12C; and DP 12A in the figure) a preamble code index for the random access procedure on the random access channel opportunity based on the information; and then, a component for sending (the one or more transceivers 12D; MEM 12B; PROG 12C; and DP 12A in the figure) a random access response for the preamble code index based on the reception, the random access response indicating that the random access procedure is successful.

[0086] In an exemplary aspect of the invention according to the above paragraphs, wherein at least the means for transmitting, identifying, receiving and sending comprises means operable by at least one processor [ Figure 3 Computer program executed by DP 12A] Figure 3 PROG 12C] encoded non-transitory computer readable medium [ Figure 3 MEM 12B].

[0087] Advantages of example embodiments according to the present invention include: Reduced computational cost for decoding RAR at the UE, i.e. energy saving; Reduced transmissions from the gNB, as PDCCH for RAR is not required, i.e. energy saving; Increased PDCCH capacity, as no budget is needed for RAR; and

[0088] Furthermore, according to an exemplary embodiment of the present invention, there is a circuit system for performing operations according to the exemplary embodiment of the present invention as invented herein. The circuit system may include any type of circuit, including content encoding circuit system, content decoding circuit system, processing circuit system, image generation circuit system, data analysis circuit system, etc.). Furthermore, the circuit system may include discrete circuit systems, application-specific integrated circuit systems (ASICs) and / or field-programmable gate array circuit systems (FPGAs), etc., as well as processors specifically configured by software to perform corresponding functions, or dual-core processors with software and corresponding digital signal processors, etc.). In addition, the necessary inputs to the circuit system and the necessary outputs from the circuit system, the functions performed by the circuit system, and the interconnection of the circuit system with other components, which may include other circuit systems (possibly via inputs and outputs), are provided to perform the exemplary embodiments of the present invention as described herein.

[0089] According to example embodiments of the present invention disclosed in this application, the provided “circuitry” may include at least one or more or all of the following: (a) hardware circuit implementation only (such as implementation in analog and / or digital circuitry only); (b) a combination of hardware circuitry and software, such as, if applicable: (i) a combination of analog and / or digital hardware circuit(s) and software / firmware; and (ii) any portion of hardware processor(s) with software (including digital signal processor(s), software and memory(s) that work together to enable a device (such as a mobile phone or server) to perform various functions, such as the functions or operations of the exemplary embodiments of the invention as invented herein; and (c) hardware circuit(s) and / or processor(s) such as microprocessor(s) or portion(s) of microprocessor(s) that requires software (e.g., firmware) for operation, but which may not be present when not required for operation.

[0090] In general, various embodiments may be implemented in hardware or dedicated circuitry, software, logic, or any combination thereof. For example, some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software that may be executed by a controller, microprocessor, or other computing device, but the invention is not limited thereto. Although various aspects of the invention may be shown and described as block diagrams, flow charts, or using some other graphical representation, it should be understood that, as non-limiting examples, the blocks, devices, systems, techniques, or methods described herein may be implemented in hardware, software, firmware, dedicated circuitry or logic, general-purpose hardware or a controller or other computing device, or some combination thereof.

[0091] Embodiments of the present invention can be practiced in various components such as integrated circuit modules. The design of integrated circuits is a highly automated process. Complex and powerful software tools are available to convert a logic level design into a semiconductor circuit design ready to be etched and formed on a semiconductor substrate.

[0092] The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. All of the embodiments described in this detailed description are exemplary embodiments provided to enable those skilled in the art to make or use the invention and are not intended to limit the scope of the invention, which is defined by the claims.

[0093] The foregoing description has provided by way of exemplary and non-limiting examples a complete description and informative description of the best method and apparatus presently contemplated by the inventors for carrying out the present invention. However, various modifications and adaptations may become apparent to those skilled in the relevant arts in view of the foregoing description when read in conjunction with the accompanying drawings and the appended claims. Nevertheless, all such and similar modifications of the teachings of this invention will still fall within the scope of this invention.

[0094] It should be noted that the terms "connect," "couple," or any variations thereof, mean any connection or coupling, direct or indirect, between two or more elements, and may encompass the presence of one or more intermediate elements between two elements that are "connected" or "coupled" together. The coupling or connection between elements may be physical, logical, or a combination thereof. As used herein, two elements may be considered to be "connected" or "coupled" together by using one or more wires, cables, and / or printed electrical connections, as well as by using electromagnetic energy, such as electromagnetic energy having a wavelength in the radio frequency region, the microwave region, and the optical (visible and invisible) region, as several non-limiting and non-exhaustive examples.

[0095] In addition, some features of the preferred embodiments of the present invention may be used to advantage without corresponding use of other features. Therefore, the above description should be considered as merely illustrative of the principles of the present invention, rather than limiting the present invention.

Claims

1. A device comprising: at least one processor; as well as at least one non-transitory memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least: identifying, by a user equipment of the communication network, a predetermined link of at least one physical random access channel opportunity for a random access channel procedure for at least one random access response physical downlink shared channel candidate based on the determined information; determining, based on the identifier, at least one random access response physical downlink shared channel candidate having a different time or frequency configuration; Based on the determination, blindly decoding the at least one random access response physical downlink shared channel candidate; as well as determining, for the at least one random access response physical downlink shared channel candidate, resources of the at least one random access response physical downlink shared channel candidate for use in a random access response to a random access channel transmission, The determining of the resource of the at least one random access response physical downlink shared channel candidate is performed without decoding a physical downlink control channel associated with the random access response physical downlink shared channel candidate. 2 . The apparatus according to claim 1 , wherein the determined information is predetermined by the user equipment or received from a network node of the communication network.

3. The apparatus according to claim 2, wherein the determined information comprises a configuration mapping of a mapping between the at least one random access response opportunity and one physical random access channel opportunity. The apparatus of claim 2 , wherein the determined information comprises random access response transmission parameters.

5. The apparatus of claim 1 , wherein the at least one non-transitory memory stores instructions that, when executed by the at least one processor, cause the apparatus to: Initiating the preamble index for a random access procedure by transmitting the preamble index on the random access channel opportunity based on the blind decoding; and The random access response is verified to be for the transmitted preamble, the verification indicating that the received random access response is in response to the transmitted preamble and that the random access response is correct and deemed to be successfully received.

6. The apparatus of claim 1 , wherein determining a resource of the at least one random access response physical downlink shared channel candidate to be used by the network node to send a random access response comprises: Based on whether the random access response message indicates the preamble index of the transmitted preamble, it is determined that the successfully decoded physical downlink shared channel candidate carries a valid random access response message.

7. A method comprising: identifying, by a user equipment of the communication network, a predetermined link of at least one physical random access channel opportunity for a random access channel procedure for at least one random access response physical downlink shared channel candidate based on the determined information; determining, based on the identifier, at least one random access response physical downlink shared channel candidate having a different time or frequency configuration; Based on the determination, blindly decoding the at least one random access response physical downlink shared channel candidate; as well as determining, for the at least one random access response physical downlink shared channel candidate, resources for a random access response to a random access channel transmission, The determining of the resource of the at least one random access response physical downlink shared channel candidate is performed without decoding a physical downlink control channel associated with the random access response physical downlink shared channel candidate.

8. The method according to claim 7, wherein the determined information is subscribed by the user equipment or received from a network node of the communication network.

9. The method according to claim 8, wherein the determined information comprises a configuration mapping of a mapping between the at least one random access response opportunity and one physical random access channel opportunity.

10. The method of claim 8, wherein the determined information comprises random access response transmission parameters.

11. The method according to claim 7, comprising: Initiating a preamble index for a random access procedure via an indexed preamble transmitted on the random access channel opportunity based on the blind decoding; as well as The random access response is verified to be for the transmitted preamble, which indicates that the received random access response is in response to the transmitted preamble and the random access response is correct and deemed to be successfully received.

12. The method of claim 7, wherein determining a resource of the at least one random access response physical downlink shared channel candidate to be used by the network node to send a random access response comprises: Based on whether the random access response message indicates the preamble index of the transmitted preamble, it is determined that the successfully decoded physical downlink shared channel candidate carries a valid random access response message.

13. An apparatus comprising: means for identifying, by a user equipment of the communications network, a predetermined linkage of at least one physical random access channel opportunity of a random access channel procedure for at least one random access response physical downlink shared channel candidate based on the determined information; means for blindly decoding at least one random access response physical downlink shared channel candidate having at least one different time configuration or frequency configuration based on the identification; as well as means for determining, based on the blind decoding, a resource for a random access response physical downlink shared channel candidate of the at least one random access response physical downlink shared channel candidate for monitoring a random access response transmitted on a random access channel, The determining of the resource of the at least one random access response physical downlink shared channel candidate is performed without decoding a physical downlink control channel associated with the random access response physical downlink shared channel candidate.

14. An apparatus comprising: at least one processor; as well as at least one non-transitory memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least: A network node of the communication network sends information including a configuration mapping of a mapping between at least one random access response opportunity and one physical random access channel opportunity to a user equipment, wherein the information identifies a predetermined link of at least one physical random access channel opportunity of a random access channel procedure for at least one random access response physical downlink shared channel candidate; receiving, based on the information, a preamble index for a random access procedure on a random access channel opportunity; as well as Based on the receiving, a random access response for the preamble index is sent, the random access response indicating that the random access procedure is successful.

15. The apparatus according to claim 14, wherein the information comprises a configuration mapping of a mapping between the at least one random access response opportunity and one physical random access channel opportunity.

16. A method comprising: A network node of the communication network sends information including a configuration mapping of a mapping between at least one random access response opportunity and one physical random access channel opportunity to a user equipment, wherein the information identifies a predetermined link of at least one physical random access channel opportunity of a random access channel procedure for at least one random access response physical downlink shared channel candidate; receiving, based on the information, a preamble index for a random access procedure on a random access channel opportunity; as well as Based on the receiving, a random access response for the preamble index is sent, the random access response indicating that the random access procedure is successful.

17. The method according to claim 16, wherein the information comprises a configuration mapping of a mapping between the at least one random access response opportunity and one physical random access channel opportunity.

18. An apparatus comprising: means for sending, by a network node of a communication network to a user equipment, information configuring a mapping comprising a mapping between at least one random access response opportunity and one physical random access channel opportunity, wherein the information identifies a predetermined link of at least one physical random access channel opportunity of a random access channel procedure for at least one random access response physical downlink shared channel candidate; means for receiving a preamble index for a random access procedure on a random access channel opportunity based on the information; as well as means for sending a random access response for the preamble index based on the receiving, the random access response indicating that the random access procedure was successful.

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