Apparatus and method for communication

Abstract

A method includes sending a message from a communication device to a transmission reception point during a random access procedure. The message includes information identifying a plurality of different beam directions. The method further includes receiving a response to the message from the plurality of different beam directions.

Description

Technical Field

[0001] The present disclosure relates to an apparatus, a method, and a computer program, and more particularly but not exclusively, to an apparatus, a method, and a computer program for use in a random access procedure. Background Art

[0002] A communication system may be regarded as a facility that enables a communication session between two or more entities (such as communication devices, base stations / access points, and / or other nodes) by providing a carrier between various entities involved in a communication path. For example, a communication system may be provided by means of a communication network and one or more compatible communication devices.

[0003] A communication system may be accessed via a suitable communication device or terminal. The communication device is provided with suitable signal receiving and transmitting means for enabling communication, such as enabling access to a communication network or directly communicating with other communication devices. The communication device may access a carrier provided by a station or access point and transmit and / or receive communication on the carrier.

[0004] Communication systems and associated devices typically operate according to a given standard or specification that defines what the various entities associated with the system are allowed to do and how it should be achieved. Summary of the Invention

[0005] According to one aspect, there is provided a method including: sending, during a random access procedure, a message from a communication device to a transmission reception point, the message including information identifying a plurality of different beam directions; and receiving, from the plurality of different beam directions, a response to the message.

[0006] The method may include receiving a reference beam signal from one or more transmission reception points.

[0007] The reference beam signal may include a synchronization signal block beam.

[0008] The method may include determining a plurality of preferred beam directions, the information identifying the preferred beam directions.

[0009] The information may include one or more of a beam identifier of a corresponding preferred beam direction and a cell identifier associated with the corresponding beam.

[0010] The message may be a MsgA message.

[0011] The response may be a MsgB message.

[0012] Information identifying multiple beam directions can be provided in the following ways: as part of uplink control information; as part of one or more media access control control elements; using a preamble index; and / or using a physical random access channel occasion.

[0013] The method can include receiving the response from multiple different beam directions substantially at the same time.

[0014] The method can include receiving the response from multiple different beam directions at different times.

[0015] The method can include combining the responses received from multiple different beam directions.

[0016] The method can include receiving configuration information indicating one or more of the following: the number of beam directions to be identified in the message; and the number of transmission reception points from which one or more beam directions are to be identified in the message.

[0017] The method can be performed by a device. The device can be in or be a communication device.

[0018] According to another aspect, a method is provided, including: receiving, during a random access procedure, a message for a transmission reception point, the message being from a communication device and including information identifying multiple different beam directions; and causing a response to the message to be sent from multiple different beam directions.

[0019] The method can include causing multiple reference beam signals to be sent to the communication device.

[0020] The reference beam signals can include synchronization signal block beams.

[0021] The information can include one or more of a beam identifier of a corresponding preferred beam direction and a cell identifier associated with the corresponding beam.

[0022] The message can be a MsgA message.

[0023] The response can be a MsgB message.

[0024] Information identifying multiple beam directions can be provided in the following ways: as part of uplink control information; as part of one or more media access control control elements; using a preamble index; using a physical random access channel occasion.

[0025] The method may include causing configuration information to be sent to the communication device, the configuration information indicating one or more of: the number of beam directions to be identified in the message; and the number of transmission reception points from which one or more beam directions are to be identified in the message.

[0026] The method may include causing a request to be sent to another transmission reception point to request the other transmission reception point to send the response in at least one beam direction among the plurality of different beam directions.

[0027] The request may include beam information indicating the at least one beam direction among the plurality of different beam directions.

[0028] The method may include receiving a message from another transmission reception point, the message including information indicating whether the response has been successfully sent from the other transmission reception point.

[0029] The method may be performed by a device. The device may be provided in or be a transmission reception point.

[0030] According to another aspect, a method is provided, including: receiving, from a transmission reception point, a request to request another transmission reception point to send a random access (RA) response message to a communication device in at least one beam direction, the request including information identifying the at least one beam direction; and causing the random access response message to be sent from the at least one beam direction.

[0031] The random access response message may be a MsgB message.

[0032] The method may include causing a message to be sent from another transmission reception point to the transmission reception point, the message including information indicating whether the random access response message has been successfully sent from the other transmission reception point.

[0033] The method may be performed by a device. The device may be provided in or be a transmission reception point.

[0034] According to another aspect, a device is provided, including components for: during a random access procedure, causing a message to be sent from a communication device to a transmission reception point, the message including information identifying a plurality of different beam directions; and receiving responses to the message from the plurality of different beam directions.

[0035] The components may be for receiving reference beam signals from one or more transmission reception points.

[0036] The reference beam signals may include synchronization signal block beams.

[0037] The component can be used to determine multiple preferred beam directions, and the information identifies the preferred beam directions.

[0038] The information can include one or more of a beam identifier of a corresponding preferred beam direction and a cell identifier associated with the corresponding beam.

[0039] The message can be a MsgA message.

[0040] The response can be a MsgB message.

[0041] The information identifying multiple beam directions can be provided in the following ways: as part of uplink control information; as part of one or more media access control elements; using a preamble index; and / or using a physical random access channel occasion.

[0042] The component can be used to receive the response from multiple different beam directions substantially at the same time.

[0043] The component can be used to receive the response from multiple different beam directions at different times.

[0044] The component can be used to combine the responses received from multiple different beam directions.

[0045] The component can be used to receive configuration information indicating one or more of: the number of beam directions identified in the message; and the number of transmission reception points from which one or more beam directions are to be identified in the message.

[0046] The device can be in or be a communication device.

[0047] According to another aspect, there is provided a device including components for: receiving, during a random access procedure, a message for a transmission reception point, the message from a communication device and including information identifying multiple different beam directions; and causing a response to the message to be sent from multiple different beam directions.

[0048] The component can be used to cause multiple reference beam signals to be sent to the communication device.

[0049] The reference beam signals can include synchronization signal block beams.

[0050] The information can include one or more of a beam identifier of a corresponding preferred beam direction and a cell identifier associated with the corresponding beam.

[0051] The message can be a MsgA message.

[0052] The response can be a MsgB message.

[0053] Information identifying multiple beam directions can be provided in the following ways: as part of uplink control information; as part of one or more media access control (MAC) control elements (CEs); using a preamble index; and / or using a physical random access channel occasion.

[0054] This component can be used to cause configuration information to be sent to the communication device, the configuration information indicating one or more of the following: the number of beam directions to be identified in the message; and the number of transmission reception points from which one or more beam directions are to be identified in the message.

[0055] This component can be used to cause a request to be sent to another transmission reception point to request the other transmission reception point to send the response in at least one of the multiple different beam directions.

[0056] The request can include beam information indicating the at least one beam direction among the multiple different beam directions.

[0057] This component can be used to receive a message from another transmission reception point, the message including information indicating whether the response has been successfully sent from the other transmission reception point.

[0058] This device can be provided in or be a transmission reception point.

[0059] According to another aspect, there is provided a device including operating components for: receiving, from a transmission reception point, a request to request another transmission reception point to send a random access response message to a communication device in at least one beam direction, the request including information identifying the at least one beam direction; and causing the random access response message to be sent from the at least one beam direction.

[0060] The random access response message can be a MsgB message.

[0061] This component can be used to cause a message to be sent from another transmission reception point to the transmission reception point, the message including information indicating whether the random access response message has been successfully sent from the other transmission reception point.

[0062] This device can be provided in or be a transmission reception point.

[0063] According to another aspect, there is provided an apparatus comprising at least one processor and at least one memory, the at least one memory including computer code for one or more programs, the at least one memory and the computer code being configured to, with the at least one processor, cause the apparatus to at least: during a random access procedure, send a message from a communication device to a transmission reception point, the message including information identifying a plurality of different beam directions; and receive a response to the message from the plurality of different beam directions.

[0064] The at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus to at least receive a reference beam signal from one or more transmission reception points.

[0065] The reference beam signal may include a synchronization signal block beam.

[0066] The at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus to at least determine a plurality of preferred beam directions, the information identifying the preferred beam directions.

[0067] The information may include one or more of a beam identifier of a corresponding preferred beam direction and a cell identifier associated with the corresponding beam.

[0068] The message may be a MsgA message.

[0069] The response may be a MsgB message.

[0070] The information identifying the plurality of beam directions may be provided by: being part of uplink control information; being part of one or more media access control elements; using a preamble index; and / or using a physical random access channel occasion.

[0071] The at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus to at least receive the response from the plurality of different beam directions substantially at the same time.

[0072] The at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus to at least receive the response from the plurality of different beam directions at different times.

[0073] The at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus to at least combine the responses received from the plurality of different beam directions.

[0074] At least one memory and computer program code may be configured to, together with at least one processor, cause the apparatus to at least receive configuration information indicating one or more of the following: the number of beam directions to be identified in the message; and the number of transmission reception points from which one or more beam directions are to be identified in the message.

[0075] The apparatus may be in or be a communication device.

[0076] According to another aspect, there is provided an apparatus comprising at least one processor and at least one memory, the at least one memory including computer code for one or more programs, the at least one memory and computer code being configured to, together with at least one processor, cause the apparatus to at least: receive, during a random access procedure, a message for a transmission reception point, the message being from a communication device and including information identifying a plurality of different beam directions; and cause a response to the message to be sent from a plurality of different beam directions.

[0077] At least one memory and computer program code may be configured to, together with at least one processor, cause the apparatus to at least cause a plurality of reference beam signals to be sent to the communication device.

[0078] The reference beam signals may include synchronization signal block beams.

[0079] The information may include one or more of a beam identifier of a corresponding preferred beam direction and a cell identifier associated with the corresponding beam.

[0080] The message may be a MsgA message.

[0081] The response may be a MsgB message.

[0082] The information identifying a plurality of beam directions may be provided by: being part of uplink control information; being part of one or more media access control (MAC) control elements (CEs); using a preamble index; and / or using a physical random access channel occasion.

[0083] At least one memory and computer program code may be configured to, together with at least one processor, cause the apparatus to at least cause configuration information to be sent to the communication device, the configuration information indicating one or more of the following: the number of beam directions to be identified in the message; and the number of transmission reception points from which one or more beam directions are to be identified in the message.

[0084] The at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus to at least cause a request to be sent to a further transmission reception point requesting the further transmission reception point to transmit the response in at least one beam direction of the plurality of different beam directions.

[0085] The request may include beam information indicating a beam direction of the at least one of the plurality of different beam directions.

[0086] The at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus to receive a message from a further transmission reception point, the message comprising information indicating whether the response has been successfully transmitted from the further transmission reception point.

[0087] The apparatus may be provided in or be a transmission reception point.

[0088] According to another aspect, a device is provided, comprising at least one processor and at least one memory, the at least one memory comprising computer code for one or more programs, the at least one memory and the computer code being configured to, together with the at least one processor, cause the device to at least: receive a request from a transmission receiving point to request another transmission receiving point to send a random access response message to a communication device in at least one beam direction, the request comprising information identifying the at least one beam direction; and cause the random access response message to be sent from the at least one beam direction.

[0089] The random access response message may be a MsgB message.

[0090] The at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus to cause a message to be sent from the further transmission reception point to the transmission reception point, the message comprising an indication of whether the random access response message has been successfully sent from the further transmission reception point.

[0091] The apparatus may be provided in or be a transmission reception point.

[0092] According to one aspect, there is provided a computer program comprising computer executable code configured to cause any of the aforementioned methods to be performed when run on at least one processor.

[0093] According to one aspect, a computer-readable medium is provided, comprising program instructions stored thereon, the program instructions being used to execute at least one of the above methods.

[0094] According to one aspect, a non-transitory computer-readable medium is provided, the non-transitory computer-readable medium including program instructions stored thereon for performing at least one of the above methods.

[0095] According to one aspect, a non-volatile tangible storage medium is provided, including program instructions stored thereon for performing at least one of the above methods.

[0096] Above, many different aspects have been described. It should be understood that additional aspects may be provided by combinations of any two or more of the above aspects.

[0097] Various other aspects are also described in the following detailed description and the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0098] Embodiments will now be described by way of example only with reference to the drawings, in which:

[0099] Figure 1 An example of a 4-step RACH process is illustrated;

[0100] Figure 2 An example of a 2-step RACH process is illustrated;

[0101] Figure 3 An example of a PUSCH (Physical Uplink Shared Channel) occasion with control and data resource elements is shown;

[0102] Figure 4 An example of a 2-step RACH process with beamforming is shown;

[0103] Figure 5 The signal flow of some embodiments of the TRP in the same cell is shown;

[0104] Figure 6 The signal flow of some embodiments of the TRP in different cells is shown;

[0105] Figure 7 A schematic diagram of an example communication system including multiple base stations and communication devices is shown;

[0106] Figure 8 A schematic diagram of an example mobile communication device is shown;

[0107] Figure 9 A schematic diagram of an example device provided in a base station is shown;

[0108] Figure 10 A schematic diagram of a non-volatile storage medium storing instructions that, when executed by a processor, allow the processor to perform one or more steps of the method of some embodiments is shown;

[0109] Figure 11 illustrates example apparatuses that may be provided in a base station or a communication device;

[0110] Figure 12 illustrates a method performed at least in part by apparatuses of a communication device;

[0111] Figure 13 illustrates a method performed at least in part by apparatuses of a primary transmission reception point;

[0112] Figure 14 illustrates a method performed at least in part by apparatuses of a secondary transmission reception point;

[0113] Figure 15 illustrates a method performed by apparatuses of a communication device;

[0114] Figure 16 illustrates a method performed by apparatuses of a primary transmission reception point; and

[0115] Figure 17 illustrates a method performed by apparatuses of a secondary transmission reception point. DETAILED DESCRIPTION

[0116] As is well known, a wireless system can be divided into cells and is thus often referred to as a cellular system. Typically, an access point (such as a base station) provides at least one cell. A cellular system can support communication between user equipments (UEs). This disclosure relates to cellular radio implementations, including 2G, 3G, 4G, and 5G radio access networks (RANs); cellular Internet of Things (IoT) RANs; and cellular radio hardware.

[0117] In the following, certain embodiments are explained with reference to a communication device capable of communicating via a wireless cellular system and a communication system serving such a communication device. Before explaining the exemplary embodiments in detail, certain general principles of wireless communication systems, their access systems, and communication devices are briefly explained to assist in understanding the technology underlying the examples described. Figures 7 to 11 Briefly explains certain general principles of wireless communication systems, their access systems, and communication devices to assist in understanding the technology underlying the examples described as the basis.

[0118] An example of a wireless communication system is an architecture standardized by the Third Generation Partnership Project (3GPP). The latest 3GPP-based development is commonly referred to as 5G or New Radio (NR). Other examples of radio access systems include those provided by base stations of systems based on technologies such as Wireless Local Area Network (WLAN) and / or WiMAX (Worldwide Interoperability for Microwave Access). It should be understood that although some embodiments are described in the context of 5G systems, other embodiments can be provided in any other suitable system, including but not limited to subsequent systems or similar protocols defined outside the 3GPP forum.

[0119] Figure 7 FIG. 1 shows a part of a wireless communication system 100. It can be seen that communication device 102 is served by cell 1 106 provided by first base station 110a. In this example, communication device 102 can be served by a second cell (cell 2) provided by second base station 110b. Depending on the system, the base station can be any suitable transmission and reception point TRP. For example, the TRP (sometimes referred to as TRxP) can be a gNB or ng-eNB or provided by a gNB or ng-eNB.

[0120] In this document, the communication device will be referred to as a UE (user equipment), but it should be understood that the device can be any suitable communication device, and the term UE is intended to cover any such device. Some examples of communication devices are discussed below, and as used in this document, the term UE is intended to cover any one or more of those devices and / or any other suitable device. The communication device has a wireless connection to a base station or other suitable TRP.

[0121] Figure 8 FIG. 2 illustrates an example of a communication device 300, such as Figure 7 the wireless communication device 102 shown above. The wireless communication device 300 can be provided by any device capable of transmitting and receiving radio signals. Non-limiting examples include a mobile station (MS) or mobile device, such as a mobile phone or a so-called "smartphone", a computer provided with a wireless interface card or other wireless interface facility (e.g., a USB dongle), a personal digital assistant (PDA) or a tablet computer provided with wireless communication capabilities, a machine type communication (MTC) device, an IoT type communication device, or any combination thereof.

[0122] Device 300 can receive signals via a suitable means for reception over the air or radio interface 307, and can transmit signals via a suitable means for transmitting radio signals. In Figure 8 FIG. 2, the transceiver means is schematically designated by block 306. The transceiver means 306 can be provided, for example, by means of a radio part and an associated antenna arrangement. The antenna means can be arranged inside or outside the mobile device.

[0123] The wireless communication device 300 may be provided with at least one processor 301 and at least one memory. The at least one memory may include at least one ROM 302a and / or at least one RAM 302b. The communication device may include other possible components 303 for use in the software and hardware assisted execution of the tasks it is designed to perform, including access to and communication with access systems and other communication devices. At least one processor 301 is coupled to at least one memory. At least one processor 301 may be configured to execute suitable software code 308 to implement one or more of the following aspects. The software code 308 may be stored in at least one memory, for example, stored in at least one ROM 302a.

[0124] The processor, memory, and other associated control means may be provided on a suitable circuit board and / or chipset. This feature is denoted by reference numeral 304.

[0125] The device may optionally have a user interface, such as a keyboard 305, a touch-sensitive screen or panel, combinations thereof, and the like.

[0126] Optionally, one or more of a display, a speaker, and a microphone may be provided depending on the type of the device.

[0127] Generally, the communication protocols and / or parameters to be used for connection are also defined. The communication device may access the communication system based on various access technologies.

[0128] Figure 9 An example device is shown. Figure 9 An example of the device 200 for a base station is shown. The device includes at least one memory. The at least one memory may be at least one random access memory (RAM) 211a and / or at least one read-only memory (ROM) 211b, at least one processor 212, 213, and an input / output interface 214. At least one processor 212, 213 is coupled to the RAM 211a and the ROM 211b. At least one processor 212, 213 may be configured to execute suitable software code 215 to implement one or more of the following aspects. The software code 215 may be stored in the ROM 211b.

[0129] Figure 10 A schematic diagram of non-volatile storage media 1600a (such as a computer disk (CD) or a digital versatile disk (DVD)) and 1600b (such as a universal serial bus (USB) memory stick) storing instructions and / or parameters 1602 is shown. The instructions and / or parameters 1602, when executed by a processor, allow the processor to execute one or more steps of any method of any embodiment.

[0130] Figure 11 Device 148 is shown. Device 148 may be provided in a TRP or a communication device. The device may include at least one processor 150 and at least one memory 152, and the at least one memory 152 includes computer code for one or more programs.

[0131] The device may be configured to cause some embodiments to be executed.

[0132] One or more of the following aspects are related to a 5G system (5GS). (5G is sometimes referred to as New Radio (NR)). However, it should be understood that some of these aspects may be used with any other suitable radio access technology system, such as UTRAN (3G radio), Long Term Evolution (LTE) of Universal Mobile Telecommunications System (UMTS), and / or any other suitable system.

[0133] Figure 1 A schematic diagram of a signaling graph of a four-step RACH (Random Access Channel procedure) is shown. This procedure may be supported in NR.

[0134] In step 1, the UE may select a RACH preamble from the configured set of RACH preambles. The UE may send the RACH preamble in one of the multiple predetermined RACH opportunities.

[0135] In step 2, the gNB may send a Random Access Response (RAR). The RAR may be generated by the Medium Access Control (MAC) layer. The RAR may provide at least one of 23 advance, an initial UL grant for sending Message 3 (Msg3), and the assignment of a Temporary Cell Radio Network Temporary Identifier (C-RNTI).

[0136] In step 3, using the UL grant provided in the RAR, the UE may send Msg 3 to the gNB. The content for Msg3 may depend on whether the UE performs initial access (Msg3 may include RRCSetupRequest), RRC reconstruction (Msg 3 may include RRCReestablishmen), handover (Msg 3 may include RRCReconfigurationComplete), or beam failure recovery (Msg 3 may include C-RNTI MAC CE). For example, this may be as described in 3GPP TS 38.331 (Release 15).

[0137] In step 4, contention resolution may be performed in Message 4 (Msg4). In the case where the UE loses the contention (e.g., due to a possible collision with another UE in the RACH preamble transmission), the UE may repeat the RACH procedure.

[0138] A two-step RACH has been proposed for NR. The two-step RACH procedure can facilitate channel access and / or enhance the connection setup / resumption procedure.

[0139] In the two-step RACH, the first message (MsgA) combines the preamble signal (Msg1) and the data signal (Msg3), while the second message (MsgB) combines the random access response (Msg2) and the contention resolution (Msg4). In this regard, refer to Figure 2 。

[0140] In step A, the UE sends MsgA to the gNB.

[0141] In step B, the gNB sends MsgB to the UE.

[0142] In some embodiments, the events that trigger the two-step RACH procedure can be the same as those for triggering the four-step RACH procedure.

[0143] By way of example only, the events that can trigger the RACH procedure can include one or more of the following events:

[0144] Initial access from the idle mode (such as the RRC (Radio Resource Control) idle mode);

[0145] Connection reestablishment procedure, such as the RRC connection reestablishment procedure;

[0146] When the UL synchronization state is "unsynchronized", DL (Downlink) or UL (Uplink) data arrives during the connected mode. The connected mode can be the RRC connected mode;

[0147] When there are no uplink control channel resources available for SR (Scheduling Request), UL data arrives during the connected mode. The connected mode can be the RRC connected mode. The uplink control channel can be the PUCCH (Physical Uplink Control Channel);

[0148] SR failure;

[0149] Request during synchronization reconfiguration (e.g., handover). The request can be an RRC request;

[0150] Transition from the inactive mode. The inactive mode can be the RRC inactive mode;

[0151] Establishing time alignment at secondary cell (SCell) addition; and

[0152] Beam failure recovery.

[0153] This is by way of example only, and in other embodiments, one or more other events can trigger the RACH procedure.

[0154] Reference Figure 3 , which shows an example of a PUSCH occasion with control and data resource elements for MsgA.

[0155] In some embodiments, for MsgA, a one-to-one and many-to-one mapping between the preamble and the associated PUSCH resource unit in each RO (RACH occasion) may be supported. To increase the probability of successfully decoding MsgA at the gNB, the UE may, for example, select different modulation and coding schemes (MCS) depending on the measured channel conditions. However, the multiple decoding scenarios at the gNB may increase the complexity of the gNB receiver. To avoid this, uplink control information (UCI) may, for example, provide information to assist the gNB in decoding the MsgA PUSCH transmission. This may be sent together with the uplink data. The information may include information on one or more of the MCS used, the payload size, and the resource size, etc. This may reduce the amount of hypothesis testing required and / or the subsequent risk of incorrect decoding.

[0156] In Figure 3 's example, MsgA includes a preamble 400 and a PUSCH occasion for the data portion 401. The MsgA data portion includes control information 402 (UCI) and data information 404. The data information is the actual data transmitted on MsgA.

[0157] In NR, for beam-based operations, different synchronization signal block (SSB) time indices are associated with different ROs (in time and / or frequency) and / or different preambles. Since different SSB time indices correspond to SSB transmissions in different downlink beams, based on the detected preamble, the network will be able to determine the best beam for the user equipment that has sent the corresponding preamble. This may be an implicit indication of the preferred beam from the UE side through preamble transmission. The network may then use this beam for downlink transmission to the user equipment.

[0158] Reference Figure 4 , which shows an example of a two-step RACH process with beamforming.

[0159] As Figure 4 shown, in step 410, the gNB is configured to send multiple SSBs to the UE on different transmission beams.

[0160] Based on the received transmission beams, the UE determines which of the received beams is the best receiving beam. In this example, the best receiving beam is labeled 409. The corresponding transmission beam on the gNB side is labeled 411.

[0161] In the next step 412, the UE transmits on the transmission beam corresponding to the best receiving beam. The UE transmits MsgA with its preamble and data. The UE also indicates its preferred SSB. The gNB receives MsgA on the receiving beam corresponding to the transmission beam labeled 411.

[0162] In step 414, the gNB transmits MsgB to the UE using the beam labeled 411. The UE receives MsgB on the beam labeled 409.

[0163] In step 416, the UE transmits on the transmission beam used in step 412. The UE transmits HARQ-ACK (Hybrid Automatic Repeat reQuest ACKnowledgment). The gNB receives the HARQ-ACK on the receiving beam of step 412.

[0164] Thus, using the two-step RACH procedure, the UE transmits a preamble on the RO associated with its selected SSB beam. By assuming beam correspondence, then MsgA and MsgB will be transmitted / received on the selected beam. One feature of using the two-step RACH may be to reduce the latency of the random access procedure.

[0165] In some embodiments, it may be desirable to transmit MsgA and / or MsgB (and their corresponding HARQ-ACK) in a relatively fast and / or relatively reliable manner. For example, this may be useful in critical use cases for random access and / or other scenarios.

[0166] The reliability of MsgB may be affected by one or more factors. This may have an adverse impact on latency. There are many different scenarios in which this may occur. The following are some examples of scenarios that may occur. For example, after transmitting MsgA, a scenario may occur in which there is misalignment or blockage on the selected SSB beam. Another example scenario may occur when the channel quality of the selected SSB is not good enough. In these scenarios, MsgB and / or the corresponding HARQ-ACK may not be received correctly. This may cause MsgB to be retransmitted multiple times and / or the UE may need to start the RACH procedure from the beginning. This may be undesirable in terms of latency and / or resource efficiency. If the UE does not receive MsgB, the UE needs to retransmit MsgA. This may increase the power consumption of the UE and / or network interference.

[0167] Some embodiments may improve the reliability and / or latency of MsgB for the two-step RACH procedure.

[0168] One or more of the options described may be used in combination with the four-step RACH procedure. For example, the preferred beam / TRP information may be included in Msg 3. Msg 4 may be transmitted through two or more beams to obtain better reliability.

[0169] In some embodiments, the UE is configured to notify the network not only of the preferred / best beam from one TRP (Transmission Reception Point), but also of the (multiple) preferred / best beams from one or more secondary TRPs.

[0170] In some embodiments, the UE is alternatively or additionally configured to notify the network of multiple preferred / best beams from one TRP (Transmission Reception Point).

[0171] This may be provided by MsgA. The network may use this information to increase the reliability of MsgB transmission, for example, by sending MsgB from one or more other TRPs rather than just from one TRP, or by using different beams from the same TRP.

[0172] In some embodiments, the UE will include information about its preferred / best beam and information about one or more other suitable beams in the MsgA transmission. This may be from the same TRP as the best beam and / or the best / preferred beam from one or more other secondary TRPs.

[0173] Beam selection may be based on the DL RS (Reference Signal) from one or more candidate TRPs.

[0174] Any suitable technique may be used to determine which beams are the preferred or best beams from different primary and secondary TRPs.

[0175] If the (multiple) other TRPs are in the same cell, the beam ID may be signaled on the physical resources associated with the best TRP. If one or more other TRPs are in different cells, the beam ID and the cell ID are signaled to the best TRP. As an example, the beam ID may be in the form of an SSB index.

[0176] This information (e.g., beam ID or beam ID with cell ID) may be carried in MsgA.

[0177] This information may be carried in MsgA as part of the uplink control information (UCI). In this case, one or more control fields may be provided for this purpose.

[0178] Alternatively or additionally, this information may be carried in MsgA as part of one or more media access control (MAC) control elements (CEs). In this case, (multiple) MAC control elements are defined for this purpose, or elements with existing MAC CEs may be defined.

[0179] Alternatively or additionally, the preamble index can be used to carry information in MsgA. With this method, the preamble space can be partitioned in such a way that the selection of the preamble index is associated with, for example, the beam ID from one or more other TRPs. To indicate the cell ID in the case of TRPs in different cells, different subsets of preamble indices can be used. In this case, the mapping between the preamble and the beam ID / cell ID can be pre-known to the UE and the gNB. For example, the gNB can send such information in an RRC message or other broadcast / unicast message.

[0180] Alternatively or additionally, the PRACH (Physical Random Access Channel) occasion (RO) can be used to carry this information. In this case, the RO associated with each SSB can be partitioned in such a way that the selection of the RO is associated with, for example, the beam ID from the corresponding TRP. To indicate the cell ID in the case of TRPs in different cells, one or more different ROs can be used.

[0181] After sending MsgA, the UE starts monitoring for the reception of MsgB from one or more TRPs on the corresponding reported beam(s).

[0182] After receiving MsgA, the best TRP can send a request to one or more reported TRPs to send MsgB to the UE. Depending on one or more of the selected beam, UE capabilities, and resource availability, MsgB can then be sent to the UE from different TRPs at the same time or at different time instances to achieve a diversity effect. Additionally, MsgB can also be sent to the UE from different beams of the same TRP.

[0183] In some embodiments, the network can control the reporting of the activation / deactivation / steering beam and / or cell information.

[0184] Refer to Figure 5 , which shows the signal flow of some embodiments of the TRP in the same cell.

[0185] In step 500, the apparatus TRP1 of the first TRP is configured to cause the first TRP to send a number of SSBs to the UE on different transmission beams.

[0186] In step 502, the apparatus TRP2 of the second TRP is configured to cause the second TRP to send a number of SSBs to the UE on different transmission beams.

[0187] Generally, step 500 and step 502 occur concurrently or more or less at the same time.

[0188] Based on the received transmission beams, the device of the UE determines which of the received beams are the best receiving beams. In this example, the best receiving beam from the first TRP is labeled 514. The corresponding transmission beam on the TRP side is labeled 515. The best receiving beam from the second TRP is labeled 513. The corresponding transmission beam on the TRP side is labeled 512.

[0189] In the next step 504, the device of the UE is configured to cause the UE to transmit to the first TRP on the transmission beam corresponding to the best / preferred receiving beam from the first TRP. The device of the UE is configured to cause the UE to transmit MsgA with its preamble and data. Additionally, information about the preferred SSB of the first TRP and the preferred SSB of the second TRP is provided.

[0190] The first TRP receives MsgA with the preferred beam information on the receiving beam corresponding to the transmission beam labeled 515.

[0191] In step 506, the device of the first TRP is configured to cause a message to be sent from the first TRP to the second TRP. The message requests the second TRP to send MsgB to the UE and provides information about the preferred SSB from the second TRP. The content of MsgB is also sent from the first TRP to the second TRP, which can be in the same request message or in a different message.

[0192] In step 508, the device of the first TRP causes the TRP to send MsgB to the UE using the beam labeled 515 and corresponding to the preferred SSB beam from the first TRP. The UE receives MsgB from the first TRP on the beam labeled 514.

[0193] In step 510, the device of the second TRP causes the TRP to send MsgB to the UE using the beam labeled 512 and corresponding to the preferred SSB beam from the second TRP. The UE receives MsgB from the second TRP on the beam labeled 513.

[0194] Steps 508 and 510 can generally occur at the same time or at different time instances. This can depend on one or more of the selected beams, UE capabilities, and resource availability.

[0195] Therefore, the device of the UE causes the UE to not only notify the first TRP (TRP1) about the preferred beam from the first TRP through MsgA, but also notify about the preferred / best beam from the second TRP (TRP2).

[0196] In some embodiments, beam selection may be based on the DL RS (Downlink Reference Signal) from those TRPs. It should be understood that any other suitable beam selection technique may alternatively or additionally be used.

[0197] Figure 5 The arrangement of shows a scenario where the first TRP and the second TRP are in the same cell. Therefore, it is only necessary to signal the beam ID to the first TRP to correctly identify the beam associated with the second TRP. Otherwise, in addition to the beam ID, the cell ID (of the second TRP) also needs to be signaled.

[0198] Refer to Figure 6 , which shows the signal flow of some embodiments where the TRPs are in different cells.

[0199] In step 600, the apparatus of the first TRP (TRP1) is configured to cause the first TRP to send a number of SSBs to the UE on different transmission beams.

[0200] In step 602, the apparatus of the second TRP, TRP2, is configured to cause the second TRP to send a number of SSBs to the UE on different transmission beams.

[0201] Generally, step 600 and step 602 occur concurrently or more or less at the same time.

[0202] Based on the received transmission beams, the apparatus of the UE determines which of the received beams are the best / preferred receiving beams. In this example, the best receiving beam from the first TRP is labeled 614. The corresponding transmission beam on the TRP side is labeled 615. The best receiving beam from the second TRP is labeled 613. The corresponding transmission beam on the TRP side is labeled 612.

[0203] In the next step 604, the apparatus of the UE is configured to cause the UE to send to the first TRP on the transmission beam corresponding to the best receiving beam from the first TRP. The apparatus of the UE is configured to cause the UE to send MsgA with its preamble and data. Additionally, information about the preferred SSB of the first TRP and the preferred SSB of the second TRP is provided together with the cell ID associated with the second TRP.

[0204] The first TRP receives MsgA with the preferred beam information on the receiving beam corresponding to the transmission beam labeled 615.

[0205] In step 606, the apparatus of the first TRP is configured to cause a message to be sent from the first TRP to the second TRP. The message requests the second TRP to send MsgB to the UE and provides information about the preferred SSB from the second TRP. The cell ID is used by the apparatus to determine which TRP is the second TRP. The content of MsgB is also sent from the first TRP to the second TRP, which may be in the same request message or in a different message.

[0206] In step 608, the apparatus of the first TRP causes the TRP to send MsgB to the UE using the beam labeled 615 and corresponding to the preferred SSB beam of the first TRP. The UE receives MsgB from the first TRP on the beam labeled 614.

[0207] In step 610, the apparatus of the second TRP causes the TRP to send MsgB to the UE using the beam labeled 612 and corresponding to the preferred SSB beam of the second TRP. The UE receives MsgB from the second TRP on the beam labeled 613.

[0208] Steps 608 and 610 can generally occur at the same time or at different time instances. This may depend on one or more of the selected beam, UE capabilities, and resource availability.

[0209] In some embodiments, the beam ID or the beam ID with the cell ID can be carried in MsgA. The beam ID or the beam ID with the cell ID can be carried as part of the UCI, part of the MAC CE, using the preamble index, or using the PRACH occasion (RO).

[0210] After sending MsgA, the apparatus of the UE causes the UE to start monitoring MsgB on the corresponding reported beams not only from TRP1 but also from TRP2.

[0211] Some embodiments may allow multiple MsgB transmissions from different TRPs or on different beams of the same TRP. In the case where one beam is blocked, another beam can be received.

[0212] Alternatively or additionally, some embodiments may perform soft combining of the received MsgB at the UE. This may be the case if the data is unicast to a single UE. This can provide an advantage in terms of the reliability and / or latency of receiving MsgB. This may mean that the two-step RACH process may have relatively high reliability and / or the latency may be relatively short.

[0213] In the case of a high load on one of the TRPs in a TRP, some embodiments may have one or more advantages. In a scenario where the number of UEs attempting to access or transmit data on a given TRP is relatively large, the number of MsgBs that may need to be transmitted may be relatively large. In some embodiments, the apparatus of the TRP with the relatively heavy load may cause a request to be sent to another TRP, which requests that the TRP send a MsgB to the UE.

[0214] Some embodiments may be used in the case of contention-based access to a radio channel. For example, some embodiments may be used with NR unlicensed access. Some examples of contention-based access to a radio channel are listen-before-talk (LBT) or clear channel assessment (CCA). In these embodiments, having the opportunity to transmit MsgB from two or more candidate responding TRPs that may have different interference scenarios may have one or more advantages.

[0215] In a classic (4-step) RACH procedure, the UE transmits a preamble associated with a selected SSB beam on the RO. In other words, the TRP (to which the preamble is sent) only knows which of its beams is the preferred beam for that UE. In a previously proposed 2-step RACH procedure, that beam would be used to transmit / receive MsgA and MsgB (and the corresponding HARQ-ACK). This assumes beam correspondence, i.e., the beam selected by the UE based on the DL RS for transmitting MsgA is also suitable for transmitting MsgB (from the gNB to the UE). However, after transmitting MsgA, the selected beam may become blocked, which means that MsgB may not be correctly received. This may cause this message to be sent multiple times and / or the RACH procedure to be restarted from the beginning. It should be understood that for various reasons, the selected SSB beam may not be the "best" beam for the UE (e.g., the best beam may increase human exposure). Therefore, embodiments that provide two or more selected SSB beams may provide a more robust system.

[0216] In some embodiments, providing such additional information about one or more alternative beams and potential TRPs to be used may be beneficial for operation in an unlicensed spectrum.

[0217] In the described embodiments, one preferred beam from one TRP and one preferred beam from another TRP are determined. In some embodiments, multiple preferred beams may alternatively or additionally be determined and used.

[0218] In some embodiments, more than two preferred beams may be determined. For example, MsgB may be transmitted on more than 2 beams.

[0219] In some embodiments, a preferred beam set is determined, and a subset of the beams of the set is determined, and MsgB is transmitted thereon.

[0220] Thus, depending on whether the other TRP is in the same cell or a different cell:

[0221] If the two TRPs are in the same cell: In this case, the UE's device causes the UE to report the beam ID.

[0222] If the two TRPs are in different cells: In this case, the UE's device causes the UE to report the beam ID and the cell ID.

[0223] As previously mentioned, the above information can be sent as part of MsgA:

[0224] As part of the uplink control information. With this alternative, the field can be provided in the uplink control information part of MsgA.

[0225] As part of the MAC CE. In this case, the control element should be defined.

[0226] Using the preamble index. In this case, the preamble space is partitioned in such a way that the selection of the preamble index is associated with, for example, the beam ID from the involved TRP. To indicate the cell ID in the case of TRPs in different cells, different subsets of preambles can be used.

[0227] Using the PRACH occasion (RO). In this case, the RO associated with each SSB is partitioned in such a way that the selection of the RO is associated with, for example, the beam ID from the corresponding TRP. To indicate the cell ID in the case of TRPs in different cells, one or more different ROs can be used.

[0228] Depending on the selected beams of each TRP, there may be a case where MsgB needs to be sent from TRP1 and TRP2 at the same time. This can happen if the selected beams are associated with the same time instance. In this case, the UE needs to be able to receive from both TRPs simultaneously. If the UE does not have such an ability, or if the network does not yet know (e.g., in the case of initial access) whether the UE has such an ability, the network can, for example, simply delay the transmission of MsgB from one of the TRPs (e.g., the secondary TRP2) until the next available opportunity. As another alternative, MsgB can be sent in a manner similar to the single-frequency network (SFN) transmission used for multicast / broadcast.

[0229] In some embodiments, the apparatus of the first TRP may attempt to send MsgB a given number of times (e.g., once or more), and in the case where the first TRP does not receive an ACK, the apparatus of the first TRP may cause the first TRP to send a request to the second TRP to request the second TRP to send MsgB.

[0230] In some embodiments, in the case where the first TRP does not receive any HARQ-ACK for the transmission of its MsgB, the apparatus of the first TRP may cause the first TRP to send a request to the second TRP to request the second TRP to send MsgB.

[0231] In some embodiments, the network may control the configuration of whether the UE reports preferred beams from a second TRP in addition to the first TRP. The network may determine the number of beams reported by the UE to the first TRP.

[0232] Reference Figure 12 shows a method performed at least in part by the apparatus of a communication device.

[0233] Optionally, in some embodiments, in step S0, the apparatus of the communication device may receive configuration information from the network, the configuration information indicating one or more of the number of beams to be reported and / or the number of TRPs from which one or more beams are to be reported. In other embodiments, the apparatus of the communication device may use one or more default values or make a determination based on one or more factors or parameters.

[0234] In step S1, the communication device receives SSB beams from one or more TRPs.

[0235] In step S2, the apparatus of the communication device determines two or more preferred SSB beams. The beams may be from the same or different TRPs.

[0236] In step S3, the apparatus of the communication device causes the communication device to send MsgA to the first TRP or the primary TRP. Beam information for the plurality of preferred beams is provided together with MsgA or as part of MsgA. The beam information may include beam identification information and / or cell information and / or any other information identifying the beam.

[0237] In step S4, the communication device receives MsgB on one or more preferred beams.

[0238] Reference Figure 13 shows a method performed at least in part by the apparatus of the primary TRP.

[0239] Optionally, in some embodiments, in step T0, the apparatus of the TRP may cause the configuration information to be sent to the communication device. The configuration information from the network may indicate one or more of the number of beams to be reported and / or the number of TRPs from which one or more beams are to be reported.

[0240] In step T1, the apparatus causes the primary TRP to transmit the SSB beam.

[0241] In step T2, the apparatus of the TRP receives MsgA and beam information. The beam information for multiple preferred beams is provided together with MsgA or as part of MsgA. The beam information may include beam identification information and / or cell information and / or any other information identifying the beam. The apparatus will determine which one or more beams are associated with the primary TRP and which one or more beams are associated with one or more secondary TRPs.

[0242] In step T3, the apparatus will cause a message to be sent to one or more secondary TRPs, requesting the corresponding TRP to send MsgB. The associated beam information is provided to the one or more secondary TRPs.

[0243] In step T4, the apparatus will cause the primary TRP to transmit MsgB on one or more preferred beams for the primary TRP.

[0244] Optionally, in step T5, the apparatus will receive a message from the secondary TRP. The message may indicate to the primary TRP the success or failure of the transmission of MsgB (from the secondary TRP).

[0245] Reference Figure 14 , which shows a method performed at least in part by the apparatus of the secondary TRP.

[0246] In step A1, the apparatus causes the secondary TRP to transmit the SSB beam.

[0247] In step A2, the secondary TRP will receive a message from the primary TRP, requesting the secondary TRP to send MsgB. The associated beam information is provided to the secondary TRP.

[0248] In step A3, the apparatus will cause the secondary TRP to transmit MsgB on one or more preferred beams for the secondary TRP.

[0249] In step A4, the apparatus will cause the secondary TRP to send a message to notify the primary TRP of the success or failure of the transmission of MsgB from the secondary TRP after receiving the HARQ-ACK feedback from the communication device.

[0250] Reference Figure 15 , which shows a method performed by the apparatus. The apparatus may be provided in or be the communication device.

[0251] In step B1, the method includes transmitting a message from a communication device to a transmission reception point or a network element during a random access procedure. The message includes information identifying a plurality of different beam directions.

[0252] In step B2, the method includes receiving a response to the message from a plurality of different beam directions.

[0253] Reference Figure 16 , which shows a method performed by a device. The device may be provided in or be a master TRP or network element, or a TRP or network element.

[0254] The method includes, in step C1, receiving, during a random access procedure, a message for a transmission reception point. The message is from a communication device and includes information identifying a plurality of different beam directions.

[0255] The method includes, in step C2, transmitting a response to the message from a plurality of different beam directions.

[0256] Reference Figure 17 , which shows a method performed by a device. The device may be provided in or be a secondary TRP or network element, or a TRP or network element.

[0257] The method includes, in step D1, receiving, from a transmission reception point, a request to request another transmission reception point to send a random access response message to a communication device in at least one beam direction. The request includes information identifying the at least one beam direction.

[0258] The method included in step D2 causes the random access response message to be sent from the at least one beam direction.

[0259] Note that although example embodiments have been described above, several variations and modifications may be made to the disclosed solution without departing from the scope of the present invention. In particular, different embodiments have been described. Different features from different embodiments may be combined.

[0260] Accordingly, embodiments may vary within the scope of the appended claims. In general, some 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 executable by a controller, microprocessor, or other computing device, although the embodiments are not limited thereto. Although various embodiments may be illustrated and described as block diagrams, flowcharts, or using some other graphical representation, it is well understood that, as a non-limiting example, 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.

[0261] These embodiments may be implemented by computer software stored in a memory and executable by at least one data processor of the entities involved, or by hardware, or by a combination of software and hardware. Further in this regard, it should be noted that any of the above processes may represent program steps, or interconnected logic circuits, blocks, and functions, or a combination of program steps and logic circuits, blocks, and functions. The software may be stored on a physical medium, such as a memory chip, or a memory block implemented within a processor, a magnetic medium (such as a hard disk or a floppy disk), and an optical medium (such as a DVD and its data variant CD).

[0262] The memory may be of any type suitable for the local technical environment and may be implemented using any appropriate data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and removable memory. The data processor may be of any type suitable for the local technical environment and, as a non-limiting example, may include one or more of the following: general purpose computers, dedicated computers, microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASICs), gate-level circuits, and processors based on multi-core processor architectures.

[0263] Alternatively or additionally, some embodiments may be implemented using circuitry. The circuitry may be configured to perform one or more of the functions and / or method steps described previously. The circuitry may be provided in a base station and / or a communication device.

[0264] As used in this application, the term "circuitry" may refer to one or more or all of the following:

[0265] (a) A pure hardware circuit implementation (such as an implementation only in analog and / or digital circuitry);

[0266] (b) A combination of hardware circuitry and software, such as:

[0267] (i) A combination of (one or more) analog and / or digital hardware circuits and software / firmware, and

[0268] (ii) Any portion of (one or more) hardware processors (including (one or more) digital signal processors), software, and (one or more) memories with software that work together to cause a device, such as a communication device or a base station, to perform the various functions described previously; and

[0269] (c) (One or more) hardware circuits and / or (one or more) processors, such as (one or more) microprocessors or a portion of (one or more) microprocessors, that require software (e.g., firmware) for operation, but the software may be absent when not required for operation.

[0270] This definition of circuitry applies to all uses of the term in this application, including in any claims. As a further example, as used in this application, the term circuitry also encompasses implementations of only hardware circuits or processors (or one or more processors) or a portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also encompasses, for example, integrated devices.

[0271] The foregoing description has provided a complete and informative description of some embodiments by way of example and not limitation. However, various modifications and adaptations may become apparent to those skilled in the relevant art when read in conjunction with the accompanying drawings and the appended claims. However, all such and similar modifications of the teachings will still fall within the scope defined by the appended claims.

Claims

1. A communication method, comprising: sending, during a random access procedure, a message from a communication device to a transmission reception point (TRP), the message including information identifying a plurality of different beam directions, wherein at least one beam of the plurality of different beam directions is from the TRP, and at least one beam of the plurality of different beam directions is from another TRP, the message triggering the sending of a request from the TRP to the other TRP, the request requesting the other TRP to send a random access response message to the communication device in at least one beam direction, the request including information identifying the at least one beam direction; and monitoring, from the plurality of different beam directions, a random access response to the message.

2. The method according to claim 1, comprising receiving a reference beam signal from one or more transmission reception points.

3. The method according to claim 2, wherein the reference beam signal includes a synchronization signal block beam.

4. The method according to any one of claims 1 to 3, comprising determining a plurality of preferred beam directions, the information identifying the preferred beam directions.

5. The method according to any one of claims 1 to 3, wherein the information includes one or more of a beam identifier of a corresponding preferred beam direction and a cell identifier associated with the corresponding beam.

6. The method according to any one of claims 1 to 3, wherein the message is a MsgA message.

7. The method according to any one of claims 1 to 3, wherein the random access response is a MsgB message.

8. The method according to any one of claims 1 to 3, wherein the information identifying the plurality of beam directions is provided by: being part of uplink control information; being part of one or more media access control control elements; using a preamble index; and / or using a physical random access channel occasion.

9. The method according to any one of claims 1 to 3, comprising receiving the random access response from the plurality of different beam directions at the same time.

10. The method according to any one of claims 1 to 3, comprising receiving the random access response from the plurality of different beam directions at different times.

11. The method according to any one of claims 1 to 3, comprising combining the random access responses received from the plurality of different beam directions.

12. The method according to any one of claims 1 to 3, comprising receiving configuration information indicating one or more of: the number of beam directions to be identified in the message; and the number of transmission reception points, from which one or more beam directions are to be identified in the message.

13. A communication method, comprising: Receiving, during a random access procedure, a message for a transmission reception point (TRP), the message being from a communication device and including information identifying a plurality of different beam directions, wherein at least one beam of the plurality of different beam directions is from the TRP, and at least one beam of the plurality of different beam directions is from another TRP; Causing a request to be sent to the another TRP to request the another TRP to send a random access response to the message on at least one of the plurality of different beam directions, the request including information identifying the at least one beam direction; And Causing the random access response to the message to be sent from the plurality of different beam directions.

14. The method according to claim 13, including causing a plurality of reference beam signals to be sent to the communication device.

15. The method according to claim 14, wherein the reference beam signal includes a synchronization signal block beam.

16. The method according to any one of claims 13 to 15, wherein the information includes one or more of a beam identifier of a corresponding preferred beam direction and a cell identifier associated with the corresponding beam.

17. The method according to any one of claims 13 to 15, wherein the message is a MsgA message.

18. The method according to any one of claims 13 to 15, wherein the random access response is a MsgB message.

19. The method according to any one of claims 13 to 15, wherein the information identifying the plurality of beam directions is provided by: being part of uplink control information; being part of one or more media access control control elements; using a preamble index; and / or using a physical random access channel occasion.

20. The method according to any one of claims 13 to 15, including causing configuration information to be sent to the communication device, the configuration information indicating one or more of: the number of beam directions to be identified in the message; and the number of transmission reception points, from which one or more beam directions are to be identified in the message.

21. The method according to any one of claims 13 to 15, wherein the request includes beam information indicating the at least one beam direction of the plurality of different beam directions.

22. A method of communication, including: Receiving, by a transmission reception point (TRP) from another TRP, a request that requests the TRP to send a random access response message to a communication device on at least one beam direction, the request including information identifying the at least one beam direction, the random access response message being a response to a message sent from the communication device to the another TRP; And Causing the random access response message to be sent from the at least one beam direction.

23. The method according to claim 22, wherein the random access response message is a MsgB message.

24. An apparatus for communication, including components for the following operations: Cause a message to be sent from a communication device to a transmission reception point (TRP) during a random access procedure, the message including information identifying a plurality of different beam directions, wherein at least one beam of the plurality of different beam directions is from the TRP and at least one beam of the plurality of different beam directions is from another TRP, the message triggering the transmission of a request from the TRP to the other TRP, the request requesting the other TRP to send a random access response message to the communication device in at least one beam direction, the request including information identifying the at least one beam direction; and Monitor for a random access response to the message from the plurality of different beam directions.

25. The apparatus according to claim 24, wherein the component is for receiving a reference beam signal from one or more transmission reception points.

26. The apparatus according to claim 25, wherein the reference beam signal includes a synchronization signal block beam.

27. The apparatus according to any one of claims 24 to 26, wherein the component is for determining a plurality of preferred beam directions, the information identifying the preferred beam directions.

28. The apparatus according to any one of claims 24 to 26, wherein the information includes one or more of a beam identifier of a corresponding preferred beam direction and a cell identifier associated with the corresponding beam.

29. The apparatus according to any one of claims 24 to 26, wherein the message is a MsgA message.

30. The apparatus according to any one of claims 24 to 26, wherein the random access response is a MsgB message.

31. The apparatus according to any one of claims 24 to 26, wherein the information identifying the plurality of beam directions is provided by: being part of uplink control information; being part of one or more media access control elements; using a preamble index; and / or using a physical random access channel occasion.

32. The apparatus according to any one of claims 24 to 26, wherein the component is for receiving the random access response from the plurality of different beam directions at the same time.

33. The apparatus according to any one of claims 24 to 26, wherein the component is for receiving the random access response from the plurality of different beam directions at different times.

34. The apparatus according to any one of claims 24 to 26, wherein the component is for combining the random access responses received from the plurality of different beam directions.

35. The apparatus according to any one of claims 24 to 26, wherein the component is for receiving configuration information indicating one or more of: the number of beam directions to be identified in the message; and the number of transmission reception points from which one or more beam directions are to be identified in the message.

36. An apparatus for communication, comprising components for the following operations: Receive, during a random access procedure, a message for a transmission reception point (TRP), the message being from a communication device and including information identifying a plurality of different beam directions, wherein at least one beam of the plurality of different beam directions is from the TRP, and at least one beam of the plurality of different beam directions is from another TRP; Cause a request to be sent to the other TRP to request the other TRP to send a random access response to the message on at least one of the plurality of different beam directions, the request including information identifying the at least one beam direction; And Cause a random access response to the message to be sent from the plurality of different beam directions.

37. The apparatus according to claim 36, wherein the component is for causing a plurality of reference beam signals to be sent to the communication device.

38. The apparatus according to claim 37, wherein the reference beam signal includes a synchronization signal block beam.

39. The apparatus according to any one of claims 36 to 38, wherein the information includes one or more of a beam identifier of a corresponding preferred beam direction and a cell identifier associated with the corresponding beam.

40. The apparatus according to any one of claims 36 to 38, wherein the message is a MsgA message.

41. The apparatus according to any one of claims 36 to 38, wherein the random access response is a MsgB message.

42. The apparatus according to any one of claims 36 to 38, wherein the information identifying the plurality of beam directions is provided by: being part of uplink control information; being part of one or more media access control control elements; using a preamble index; and / or using a physical random access channel occasion.

43. The apparatus according to any one of claims 36 to 38, wherein the component is for causing configuration information to be sent to the communication device, the configuration information indicating one or more of: the number of beam directions to be identified in the message; and the number of transmission reception points, from which one or more beam directions are to be identified in the message.

44. The apparatus according to any one of claims 36 to 38, wherein the request includes beam information indicating the at least one beam direction of the plurality of different beam directions.

45. An apparatus for communication, comprising components for: Receiving, by a transmission reception point (TRP), from another TRP a request that requests the TRP to send a random access response message to a communication device on at least one beam direction, the request including information identifying the at least one beam direction, the random access response message being a response to a message sent from the communication device to the other TRP; and Causing the random access response message to be sent from the at least one beam direction.

46. The apparatus according to claim 45, wherein the random access response message is a MsgB message.

47. A device for communication, comprising at least one processor and at least one memory, the at least one memory including computer code for one or more programs, the at least one memory and the computer code being configured to, together with the at least one processor, cause the device to at least: Cause a message to be sent from a communication device to a transmission reception point (TRP) during a random access procedure, the one message including information identifying a plurality of different beam directions, wherein at least one beam of the plurality of different beam directions is from the TRP, and at least one beam of the plurality of different beam directions is from another TRP, the one message triggering the transmission of a request from the TRP to the other TRP, the request requesting the other TRP to send a random access response message to the communication device in at least one beam direction, the request including information identifying the at least one beam direction; and Monitor for a random access response to the one message from a plurality of different beam directions.

48. The device according to claim 47, wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the device to at least receive a reference beam signal from one or more transmission reception points.

49. The device according to claim 48, wherein the reference beam signal includes a synchronization signal block beam.

50. The device according to any one of claims 47 to 49, wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the device to at least determine a plurality of preferred beam directions, the information identifying the preferred beam directions.

51. The device according to any one of claims 47 to 49, wherein the information includes one or more of a beam identifier of a corresponding preferred beam direction and a cell identifier associated with the corresponding beam.

52. The device according to any one of claims 47 to 49, wherein the one message is a MsgA message.

53. The device according to any one of claims 47 to 49, wherein the random access response is a MsgB message.

54. The device according to any one of claims 47 to 49, wherein the information identifying the plurality of beam directions is provided by: being part of uplink control information; being part of one or more media access control control elements; using a preamble index; and / or using a physical random access channel occasion.

55. The device according to any one of claims 47 to 49, wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the device to at least receive the random access response from the plurality of different beam directions at the same time.

56. The apparatus according to any one of claims 47 to 49, wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to receive the random access response from the plurality of different beam directions at least at different times.

57. The apparatus according to any one of claims 47 to 49, wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to at least combine the random access responses received from the plurality of different beam directions.

58. The apparatus according to any one of claims 47 to 49, wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to receive configuration information indicating one or more of the following: the number of beam directions to be identified in the one message; and the number of transmission reception points, from which one or more beam directions are to be identified in the one message.

59. An apparatus for communication, comprising at least one processor and at least one memory, the at least one memory including computer code for one or more programs, the at least one memory and the computer code being configured to, together with the at least one processor, cause the apparatus to at least: receive, during a random access procedure, a message for a transmission reception point (TRP), the message being from a communication device and including information identifying a plurality of different beam directions, wherein at least one beam of the plurality of different beam directions is from the TRP and at least one beam of the plurality of different beam directions is from another TRP; send a request to the another TRP to request the another TRP to send a random access response to the message on at least one beam direction of the plurality of different beam directions, the request including information identifying the at least one beam direction; and cause the random access response to the message to be sent from the plurality of different beam directions.

60. The apparatus according to claim 59, wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to send at least a plurality of reference beam signals to the communication device.

61. The apparatus according to claim 60, wherein the reference beam signal includes a synchronization signal block beam.

62. The apparatus according to any one of claims 59 to 61, wherein the information includes one or more of a beam identification of a corresponding preferred beam direction and a cell identification associated with the corresponding beam.

63. The apparatus according to any one of claims 59 to 61, wherein the one message is a MsgA message.

64. The apparatus according to any one of claims 59 to 61, wherein the random access response is a MsgB message.

65. The apparatus according to any one of claims 59 to 61, wherein the information identifying the plurality of beam directions is provided by: being part of uplink control information; being part of one or more media access control control elements; using a preamble index; and / or using a physical random access channel occasion.

66. The apparatus according to any one of claims 59 to 61, wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to at least cause configuration information to be sent to the communication device, the configuration information indicating one or more of: the number of beam directions to be identified in the one message; and the number of transmission reception points from which one or more beam directions are to be identified in the one message.

67. The apparatus according to any one of claims 59 to 61, wherein the request includes beam information indicating at least one of the plurality of different beam directions.

68. An apparatus for communication, comprising at least one processor and at least one memory, the at least one memory including computer code for one or more programs, the at least one memory and the computer code being configured to, together with the at least one processor, cause the apparatus to at least: receive, by a transmission reception point (TRP) from another TRP, a request that requests the TRP to send a random access response message to a communication device in at least one beam direction, the request including information identifying the at least one beam direction, the random access response message being a response to a message sent from the communication device to the other TRP; and cause the random access response message to be sent from the at least one beam direction.

69. The apparatus according to claim 68, wherein the random access response message is a MsgB message.

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