Communication device, infrastructure equipment and method

Abstract

A method for operating a communication device in a wireless communication network, the method comprising: sending a random access message on a wireless access interface, the random access message comprising a selected random access preamble and a transmission on a shared channel, the shared channel transmission using a demodulation reference signal (DMRS) according to one or more selected DMRS parameters; receiving a resource allocation message, the resource allocation message comprising an indication of sending a resource allocation message in response to the random access message and an indication of allocating downlink communication resources for transmission of a random access response message; receiving a signal sent using the allocated downlink communication resources; determining that the resource allocation message identifies the communication device; and in response to determining that the resource allocation message identifies the communication device, decoding the signal sent using the allocated downlink communication resources; wherein the resource allocation message comprises an indication of identifying the communication device based on an index associated with the selected random access preamble and one or more of the selected one or more DMRS parameters.

Description

Technical Field

[0001] The present disclosure relates to a communication device, infrastructure equipment, and a method for the communication device to receive data in a wireless communication network. Background Art

[0002] The "background technology" description provided herein is for the purpose of generally presenting the context of the present disclosure. To the extent described in this background technology section, the work of the inventors currently named and the description that may not qualify as prior art at the time of filing are neither explicitly nor implicitly admitted to be prior art against the present invention.

[0003] Third and fourth generation mobile telecommunication systems, such as those based on the UMTS and Long Term Evolution (LTE) architectures defined by 3GPP, are capable of supporting more sophisticated services than the simple voice and messaging services provided by previous generations of mobile telecommunication systems. For example, utilizing the improved radio interface and enhanced data rates provided by the LTE system, users are able to enjoy high data rate applications, such as mobile video streaming and mobile video conferencing, which were previously only available via fixed line data connections. Therefore, there is a strong demand for the deployment of such networks and the coverage areas of these networks (i.e., the geographical locations where the networks can be accessed) can be expected to increase more rapidly.

[0004] Future wireless communication networks are expected to support routine and efficient communication with a wider range of devices associated with a wider range of data traffic profiles and types than currently supported by system optimizations. For example, future wireless communication networks are expected to efficiently support communications with devices including reduced complexity devices, machine type communication (MTC) devices, high resolution video displays, virtual reality headsets, etc. Some of these different types of devices may be deployed in very large numbers, such as low complexity devices used to support the "Internet of Things", and may typically be associated with the transmission of relatively small amounts of data with relatively high latency tolerances.

[0005] In view of this, it is expected that future wireless communication networks, such as those referred to as 5G or New Radio (NR) systems / New Radio Access Technology (RAT) systems [1], as well as future iterations / versions of existing systems, will efficiently support connectivity to a wider range of devices associated with different applications and different characteristic data traffic profiles.

[0006] An example of such a new service is called an Ultra-Reliable Low-Latency Communication (URLLC) service, which, as the name implies, requires data units or packets to be communicated with high reliability and with low communication latency. Therefore, URLLC type services represent challenging examples for both LTE type communication systems and 5G / NR communication systems.

[0007] The increased use of different types of communication devices associated with different traffic profiles creates new challenges to effectively handle communications in wireless telecommunication systems that require addressing.

[0008] European Patent Application EP19200292 from which this application claims priority, the entire contents of which are incorporated herein by reference. Summary of the invention

[0009] The present disclosure can help solve or alleviate at least some of the problems discussed above.

[0010] Accordingly aspects and features of the disclosure are defined in the appended claims.

[0011] It should be understood that both the above overall description and the following detailed description are exemplary rather than limiting of the present technology. The described embodiments and further advantages can be better understood by referring to the following detailed description in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] A more complete understanding of the present disclosure and its many attendant advantages will be readily obtained as the present disclosure and its many attendant advantages become better understood by referring to the following detailed description when considered in conjunction with the accompanying drawings wherein like reference numerals designate identical or corresponding parts throughout the several views, and:

[0013] Figure 1 schematically represents some aspects of an LTE-type wireless telecommunications system that may be configured to operate in accordance with certain embodiments of the present disclosure;

[0014] Figure 2 schematically represents some aspects of a new radio access technology (RAT) wireless telecommunications system that may be configured to operate in accordance with certain embodiments of the present disclosure;

[0015] Figure 3 is a schematic block diagram of example infrastructure equipment and communication devices that may be configured in accordance with example implementations;

[0016] Figure 4 shows a typical 4-step RACH procedure used in LTE systems;

[0017] Figure 5 A typical 2-step RACH procedure is shown;

[0018] Figure 6 shows a message sequence chart transmitted by a base station and a communication device according to an embodiment of the present technology;

[0019] Figure 7A process flow diagram illustrating a process performed by a communication device according to an embodiment of the present technology; and

[0020] Figure 8 A process of a base station according to an embodiment of the present technology is shown. DETAILED DESCRIPTION

[0021] Long Term Evolution (4G) Advanced Radio Access Technology

[0022] Figure 1 A schematic diagram is provided showing some basic functions of a mobile telecommunication network / system 100 that operates overall according to FTE principles, but which may also support other radio access technologies, and which may be adapted to implement embodiments of the present disclosure as described herein. Figure 1 Specific aspects of the various elements and their respective modes of operation are well known and defined in the relevant standards managed by the 3GPP (RTM) body and are also described in many books on the subject (e.g., Holma H. ​​and Toskala A [2]). It should be understood that the operational aspects of the telecommunications network discussed herein and not specifically described (e.g., relating to specific communication protocols and physical channels for communication between the different elements) may be implemented according to any known techniques, for example, according to the relevant standards and known proposed modifications and additions to the relevant standards.

[0023] The network 100 includes a plurality of base stations 101 connected to a core network portion 102. Each base station provides a coverage area 103 (e.g., a cell) within which data can be transmitted to and from a communication device 104. Data is sent from a base station 101 to a communication device 104 within its respective coverage area 103 via a radio downlink. Data is sent from a communication device 104 to a base station 101 via a radio uplink. The core network portion 102 routes data to and from the communication device 104 via the respective base station 101 and provides functions such as authentication, mobility management, charging, etc. A communication device may also be referred to as a mobile station, user equipment (UE), user terminal, mobile radio, terminal device, etc. A base station, as an example of a network infrastructure device / network access node, may also be referred to as a transceiver station / nodeB / e-nodeB, g-nodeB (gNB), etc. In view of this, different terms are often associated with different generations of wireless telecommunication systems providing elements of broadly comparable functionality. However, example embodiments of the present disclosure may also be implemented in different generations of wireless telecommunication systems, such as 5G or New Radio as explained below, and for simplicity, specific terminology may be used regardless of the underlying network architecture. That is, the use of specific terminology related to specific example implementations is not intended to indicate that these implementations are limited to the specific generation of networks most associated with the specific terminology.

[0024] New Radio Access Technology (5G)

[0025] Figure 2 is a schematic diagram showing a network architecture of a new RAT wireless communication network / system 200 based on a previously proposed scheme that may also be adapted to provide functionality according to embodiments of the present disclosure described herein. Figure 2The new RAT network 200 represented in the figure comprises a first communication cell 201 and a second communication cell 202. Each communication cell 201, 202 comprises a control node (centralized unit) 221, 222 that communicates with a core network component 210 via a corresponding wired or wireless link 251, 252. The corresponding control nodes 221, 222 each also communicate with a plurality of distributed units (radio access nodes / remote transmission and reception points (TRP)) 211, 212 in their corresponding cells. Again, these communications can be performed via corresponding wired or wireless links. The distributed units 211, 212 are responsible for providing a radio access interface for communicating with devices connected to the network. Each distributed unit 211, 212 has a coverage area (radio access footprint) 241, 242, wherein, under the control of the control node, the sum of the coverage areas of the distributed units together defines the coverage of the corresponding communication cells 201, 202. Each distributed unit 211 , 212 includes a transceiver circuit for sending and receiving wireless signals and a processor circuit configured to control the corresponding distributed unit 211 , 212 .

[0026] In terms of broad top-level features, Figure 2 The core network component 210 of the new RAT communication network represented in FIG. 2 can be broadly viewed as being similar to Figure 1 1 and the corresponding control nodes 221, 222 and their associated distributed units / TRPs 211, 212 can be broadly regarded as providing Figure 1 The term network infrastructure equipment / access node may be used to cover these elements in a wireless communication system as well as more conventional base station type elements. Depending on the application in question, the responsibility for scheduling transmissions scheduled over the radio interface between the corresponding distributed unit and the communication device may belong to the control node / centralized unit and / or the distributed unit / TRP.

[0027] exist Figure 2 2 shows a communication device or UE 260 located in the coverage area of ​​the first communication cell 201. Thus, the communication device 260 can exchange signaling with the first control node 221 in the first communication cell via one distributed unit 211 associated with the first communication cell 21. In some cases, communications of a given communication device are routed through only one distributed unit, but it should be understood that in some other implementations, for example, in a soft handover scenario or other scenarios, communications associated with a given communication device can be routed through more than one distributed unit.

[0028] exist Figure 2In the example, for simplicity, two communication cells 201, 202 and one communication device 260 are shown, but it should be understood that in practice, the system may include a larger number of communication cells (each communication cell is supported by a corresponding control node and multiple distributed units) serving a larger number of communication devices.

[0029] It should be further understood that Figure 2 It only represents one example of a proposed architecture of a new RAT communication system in which the scheme according to the principles described herein may be employed, and the functions disclosed herein may also be applied in wireless communication systems having different architectures.

[0030] Thus, according to Figure 1 and Figure 2 The example embodiments of the present disclosure discussed herein are implemented in a wireless telecommunications system / network with various different architectures of the example architectures shown in . Thus, it should be understood that the specific wireless communication architecture in any given implementation is not of primary significance to the principles described herein. In view of this, the example embodiments of the present disclosure may be generally described in the context of communications between network infrastructure equipment / access nodes and communication devices, wherein the specific nature of the network infrastructure equipment / access nodes and communication devices depends on the network infrastructure of the implementation in question. For example, in some scenarios, the network infrastructure equipment / access nodes may include base stations, such as Figure 1 , adapted to provide functionality according to the principles described herein, and in other examples, the network infrastructure equipment / access node may include Figure 2 , adapted to provide functionality according to the principles described herein.

[0031] exist Figure 3 UE / communication device 270 (which can be used with Figure 2 The communication device 260 or Figure 1 104) and a more detailed illustration of an example network infrastructure device 272, which can be considered as a combination of a gNB 101 or a control node 221 and a TRP 211. Figure 3 2, but as generally shown by arrow 274 from UE 270 to infrastructure equipment 272, UE 270 is shown as sending uplink data to infrastructure equipment 272 via uplink resources of the wireless access interface. Similarly, as indicated by arrow 288 from infrastructure equipment 272 to UE 270, UE 270 can be configured to receive downlink data sent by infrastructure equipment 272 via downlink resources. Figure 1 and Figure 2 , the infrastructure equipment 272 is connected to the core network 276 via an interface 278 to a controller 280 of the infrastructure equipment 272. The infrastructure equipment 272 includes a receiver 282 connected to an antenna 284 and a transmitter 286 connected to the antenna 284. Correspondingly, the UE 270 includes a controller 290 connected to the receiver 292 that receives signals from the antenna 294 and a transmitter 296 also connected to the antenna 294.

[0032] The controller 280 is configured to control the infrastructure equipment 272 and may include a processor circuit which in turn may include various sub-units / sub-circuits for providing the functionality further elucidated herein. These sub-units may be implemented as discrete hardware elements or appropriately configured functions of the processor circuit. Thus, the controller 280 may include circuits that are appropriately configured / programmed to provide the desired functionality using conventional programming / configuration techniques for devices in wireless wire systems. The transmitter 286 and receiver 282 may include signal processing and radio frequency filters, amplifiers, and circuits according to conventional arrangements. For ease of representation, the Figure 3 286, receiver 282, and controller 280 are schematically shown as separate elements. However, it should be understood that the functionality of these elements can be provided in a variety of different ways (e.g., using one or more appropriately programmed programming computers, or one or more appropriately configured application specific integrated circuits / circuits / chips / chip sets). It should be understood that the infrastructure equipment 272 typically includes various other elements associated with its operating functions.

[0033] Correspondingly, the controller 290 of the UE 270 is configured to control the transmitter 296 and the receiver 292 and may include a processor circuit, which in turn may include various sub-units / sub-circuits for providing the functions further explained herein. These sub-units may be implemented as discrete hardware elements or appropriately configured functions of the processor circuit. Thus, the controller 290 may include circuits that are appropriately configured / programmed to provide the required functions using conventional programming / configuration techniques for devices in wireless telecommunications systems. Similarly, the transmitter 296 and the receiver 292 may include signal processing and radio frequency filters, amplifiers, and circuits according to conventional arrangements. For ease of representation, in Figure 3 Schematically illustrated in FIG. 2 are transmitter 296, receiver 292, and controller 290 as separate elements. However, it will be appreciated that the functionality of these elements can be provided in a variety of different ways (e.g., using one or more appropriately programmed computers, or one or more appropriately configured application specific integrated circuits / circuits / chips / chip sets). It will be appreciated that the communication device 270 typically includes various other elements associated with its operating functionality, such as a power supply, a user interface, etc., but for simplicity, the components are not shown in FIG. Figure 3 These elements are not shown in FIG.

[0034] The controllers 280, 290 may be configured to execute instructions stored on a computer readable medium, such as a non-volatile memory. For example, the process steps described herein may be performed by a microprocessor in conjunction with a random access memory, the microprocessor operating according to instructions stored on a computer readable medium.

[0035] 5G, URLLC, and Industrial IoT

[0036] Systems incorporating NR technology are expected to support different services (or service types), which can be characterized by different requirements for latency, data rate, and / or reliability. For example, enhanced mobile broadband (eMBB) services are characterized by the need to support high capacity up to 20 Gb / s. For a single transmission of a 32-byte packet with a user plane latency of 1 ms [3], the requirements for Ultra-Reliable and Low-Latency Communication (URLLC) services are 1-10 -5 (99.999%) or higher reliability. In some scenarios, there may be a user plane delay of 0.5ms or 1ms, 1-10 -6 Massive Machine Type Communications (mMTC) is another example of a service that can be supported by NR-based communication networks.

[0037] In addition, the system can be expected to support further enhancements related to the Industrial Internet of Things (IIoT) to support services with new requirements for high availability, high reliability, low latency, and in some cases high accuracy positioning.

[0038] Industrial automation, energy distribution, and intelligent transportation systems are examples of new use cases for the Industrial Internet of Things (IIoT). In the example of industrial automation, the system may involve different distributed components that work together. These components may include sensors, virtualized hardware controllers, and automated robots that can initiate actions or react to critical events that occur within the factory and communicate over a local area network.

[0039] Thus, for example, UEs in the network may be expected to handle a mix of different traffic associated with different applications and potentially different quality of service requirements (such as maximum delay, reliability, packet size, throughput). Some messages for transmission may be time sensitive and associated with strict deadlines, and therefore the communication network may need to provide Time Sensitive Networking (TSN) [6].

[0040] In order to meet the requirements of IIoT, i.e., high availability, high reliability, low latency, and in some cases high accuracy positioning [1], URLLC services are needed. Some IIoT services can be achieved by using a hybrid of eMBB and URLLC technologies, where some data is sent by eMBB and other data is sent by URLLC.

[0041] Conventional 4-step RACH

[0042] In wireless telecommunications networks such as LTE type networks, there are different radio resource control (RRC) modes for terminal devices. For example, an RRC idle mode (RRC_IDLE) and an RRC connected mode (RRC_CONNECTED) are generally supported. For example, because uplink data needs to be sent or in response to a paging request, a terminal device in idle mode can be transformed into connected mode by performing a random access procedure. The random access procedure involves the terminal device sending a preamble on a physical random access channel, and therefore the procedure is generally referred to as a RACH or PRACH procedure / process.

[0043] In addition to a terminal device connecting to the network deciding to initiate a random access procedure itself, the network (e.g. a base station) may also instruct a terminal device in connected mode to initiate a random access procedure by sending an instruction to the terminal device to do so. Sometimes such instructions are referred to as physical downlink control channel commands (PDCCH commands), see, for example, section 5.3.3.1.3 of ETSI TS 136213 V13.0.0 (2016-01) / 3GPP TS 36.212 version 13.0.0 version 13 [7]. There are various scenarios in which a network-triggered RACH procedure (PDCCH command) may occur.

[0044] Figure 4 As shown by reference Figure 1 The description may also be applied to references such as Figure 2A typical RACH procedure used in an LTE system of the described NR wireless communication system. A communication device (or UE) 104 in a deactivated or idle mode may have some data that needs to be sent to the network. Therefore, the UE sends a random access preamble 420 (message 1) to the gNodeB 101. The random access preamble 420 indicates the identity of the communication device 104 to the gNodeB 101, so that the gNodeB 101 can address the communication device 104 during the subsequent stages of the RACH procedure. Assuming that the random access preamble 420 is successfully received by the gNodeB 101, the gNodeB 101 sends a random access response 422 message (message 2) to the communication device 104 based on the identity indicated in the received random access preamble 420. The random access response 422 message carries a further identifier allocated by the gNodeB 101 to identify the communication device 104, as well as a timing advance value (enabling the communication device 104 to change its timing to compensate for the round-trip delay caused by its distance from the gNodeB 101) and authorizing uplink resources for the communication device 104 to send data.

[0045] After receiving the random access response message 422, the communication device 104 sends a scheduled transmission of data 424 to the gNodeB 101 (message 3) using the identifier assigned to it in the random access response message 422. The scheduled transmission of data 424 is then successfully received by the gNodeB 101 assuming no collision with other UEs, which may occur if another UE sends the same random access preamble 420 to the gNodeB 101 at the same time and using the same frequency resources as the communication device 104. The gNodeB 101 responds to the scheduled transmission 424 with a contention resolution message 426 (message 4).

[0046] In 5G / NR systems, a "deactivated" RRC state may be used, where the UE can start data transmission in the deactivated state with low latency without transitioning to the connected state. Various possible solutions have been proposed to allow this operation.

[0047] 2-Step RACH Procedure

[0048] The development of a faster transmission of data for a particular application is referred to as 2-step RACH

[10] . It will be appreciated that the 2-step RACH procedure can provide a facility for transmitting data more quickly than the 4-step RACH procedure. Accordingly, it has been proposed to develop a general MAC procedure that covers both the physical layer and higher layer aspects of the 2-step RACH procedure. In general, the benefit of the 2-step RACH procedure is that it reduces the time used for connection setup / recovery procedures compared to the 4-step RACH procedure. For example, in an ideal case, the 2-step RACH reduces latency by halving the number of steps from 4 to 2 for initial access to the UE. In addition, the 2-step RACH procedure is considered to have potential benefits for channel access in NR unlicensed spectrum (NR-U) (e.g., see

[11] ).

[0049] Broadly, 2-step RACH allows the transmission of the random access preamble 420 to be combined with Figure 4 The transmission of the data 424 in is combined into an initial transmission ("message A" or "MsgA"), and similarly, the transmission of the random access response 422 and the contention resolution message 426 are combined into a response ("message B", or "MsgB").

[0050] A fallback procedure may be provided to allow a RACH procedure initiated according to the specification of 2-step RACH to replace the procedure conducted according to 4-step RACH.2-step RACH is applicable to a communication device in RRC_Deactivated, RRC_Connected and RRC_Idle states.

[0051] exist Figure 5 A message flow diagram illustrating a 2-step RACH procedure is shown in FIG. As the name implies, in a 2-step RACH procedure, there are only the following two steps:

[0052] 1. UE 201 sends message A 562, which includes the RACH preamble 564 sent in message 3 of the 4-step RACH procedure and data (on a shared uplink channel, such as a physical uplink shared channel PUSCH) 566. More specifically, as explained below, selecting a particular preamble can preconfigure the communication device 104 to send data in preconfigured resources of the uplink shared channel.

[0053] 2. The base station 101 which successfully receives the message A 562 responds with a message B 568 which combines the RAR (message 2) of the 4-step RACH procedure sent in message 4 of the 4-step RACH procedure and the corresponding data (PDSCH).

[0054] Downlink control information

[0055] Prior to a downlink message such as Message B or Message 2 (ie, a message sent by base station 102), transmission of downlink control information (DCI) as a resource allocation message may be performed to indicate downlink communication resources on which the downlink message is sent.

[0056] Thus, a communication device that recently sent a message A or a random access request may monitor the downlink control channel on which the DCI is sent. The communication device may determine that the DCI allocates resources for a message sent as part of a RACH procedure based on the temporary identifier used to encode the DCI. For example, the DCI may be encoded using a random access radio network temporary identifier (RA-RNTI) that is specifically pre-allocated for the purpose of encoding the DCI, and the DCI allocates resources for a random access response (RAR) message.

[0057] If the communication device detects that the DCI has been encoded using the RA-RNTI, it may begin attempting to decode a signal sent using the communication resources allocated by the DCI to recover the random access response message (eg, message B or message 2).

[0058] UE identification in RACH procedure

[0059] During the RACH procedure (2-step or 4-step), the communication device may be identified by various means to avoid the possibility that the communication device believes that the downlink message is intended for it, when in fact the message is intended for (or in response to) a different communication device.

[0060] For example, in a random access response of a 4-step procedure, the UE identity may include an index associated with the preamble used in the random access request. Thus, if two communication devices simultaneously send a random access preamble using the same frequency resources but have selected different preambles, it may be determined which random access response the communication device is facing.

[0061] In the 2-step RACH procedure, another UE identity may be used to encode the DCI allocating resources for message B. For example, instead of the RA-RNTI described above, the DCI may be encoded using a "MsgB-RNTI" derived based on the time and frequency resources used for the MsgA transmission. For example, as described in [5], the MsgB-RNTI may be determined as follows:

[0062] MsgB-RNTI=1+s_id+

[0063] 14×t_id+

[0064] 14×80×f_d+

[0065] 14×80×8×ul_carrier_id

[0066] Where s_id is the index of the first OFDM symbol of the PRACH opportunity (0<s_id<14), t_id is the index of the first time slot of the PRACH opportunity in the system frame (0<t_id<80), wherein the subcarrier spacing for determining t_id is based on the μ value specified in subclause 5.3.2 of 3GPP TS38.211

[12] , f_id is the index of the PRACH opportunity in the frequency domain (0<f_id<8), and u1_carrier_id is the UL carrier used for random access preamble transmission (0 for NUL carrier and 1 for SUL carrier).

[0067] Thus, a communication device receiving DCI after sending MsgA can decode the allocated downlink resources indicated in the DCI only if the RNTI of the DCI matches the MsgB-RNTI value calculated based on the communication device's transmission of the random access request.

[0068] It should be understood that although MsgB-RNTI can be regarded as an identification of a communication device, since multiple communication devices can use communication resources that generate the same MsgB-RNTI value to send random access preamble codes, MsgB-RNTI cannot guarantee that a specific communication device can be uniquely identified.

[0069] In the 2-step procedure, after receiving MsgB, contention resolution is completed. This is because MsgA includes not only the random access preamble, but also a temporary identity. The temporary identity may be locally unique and assigned by the communication network, for example, by the base station 101, and may be a cell-RNTI (C-RNTI).

[0070] If the communication device does not have a valid C-RNTI, it may generate a random RNTI value to be included in MsgA.

[0071] In any case, the random access response (RAR) includes the identity included by the UE in Msg A. Even if the UE identity is a random value, the probability of a collision is very low, so there is a very high probability that only one communication device thinks that the RAR is addressed to it.

[0072] In order to improve the efficient use of communication resources for sending random access response (RAR) messages, responses to multiple random access request messages may be combined in a single MsgB. Multiple RAR messages may be directed to different communication devices. For each MsgA responding to multiple RAR messages, the MsgB-RNTI may need to be valid. For example, multiple RAR messages may be combined in a single MsgB only if the parameter sets s_id, t_id, f_id, and u1_carrier_id associated with each MsgA responding to the RAR messages are the same.

[0073] In contrast, in some scenarios, MsgB may include a message that includes data that requires reliable delivery to a receiving communication device. For example, the data may be a radio resource configuration (RRC) message directed to the communication device, the RRC message being associated with a signaling radio bearer (SRB). It has been proposed to permit the use of a hybrid automatic repeat request (HARQ) process to provide for the transmission of confirmation information, and subsequent retransmission of the data (if necessary). Thus, in order to ensure reliable delivery, confirmation information about the data may be sent, and if the confirmation information indicates that the data was not successfully received, the data may be retransmitted one or more times (if necessary).

[0074] However, a consequence of using HARQ is that it is not possible to multiplex any other RARs with data that requires reliable delivery in a single MsgB.

[0075] It should be further understood that multiple communication devices may be in a state at the same time where a MsgA has been sent but a RAR has not yet been received. According to current technology, these communication devices must decode each MsgB in which their DCI is encoded using a MsgB-RNTI that matches the parameters used for the transmission of their MsgA. In fact, if the decoded MsgB does not include a RAR in response to the MsgA sent by the communication device, this may result in the communication device performing unnecessary decoding steps even if the associated DCI has a 'valid' MsgB-RNTI corresponding to the MsgA.

[0076] Therefore, it is necessary to ensure that MsgB (second message) can reliably transmit data in the two-step RACH procedure and that the communication device can effectively receive MsgB including the RAR in response to MsgA transmitted by the communication device.

[0077] Embodiments of the present technology can provide a method for operating a communication device in a wireless communication network, the method comprising: sending a random access message on a wireless access interface, the random access message comprising a selected random access preamble and a transmission on a shared channel, the shared channel transmission using a demodulation reference signal (DMRS) according to one or more selected DMRS parameters; and receiving a resource allocation message, the resource allocation message comprising an indication of sending a resource allocation message in response to the random access message and an indication of allocating downlink communication resources for the transmission of a random access response message. The method further comprises: receiving a signal sent using the allocated downlink communication resources; determining that the resource allocation message identifies the communication device; and in response to determining that the resource allocation message identifies the communication device, decoding a signal sent using the allocated downlink communication resources; wherein the resource allocation message comprises an indication of identifying the communication device based on an index associated with the selected random access preamble and one or more of the selected one or more DMRS parameters.

[0078] Some embodiments of the present technology provide an indication in the resource allocation message that confirmation information is sent by the communication device, indicating the reception status of the data sent using the allocated resources. Thus, even if the communication device fails to decode the data, the request to send confirmation information can be known. The communication device can also be informed of the possibility of data retransmission, and thus, the soft decoding bits generated when the decoding attempt is unsuccessful can be stored to be determined for decoding subsequent retransmissions of the data.

[0079] Some embodiments provide enhanced UE identification information within a resource allocation message to enable a communication device to determine, based on the resource allocation message, that it is not necessary to attempt to decode a signal sent using the indicated allocated resources. Compared to conventional techniques, the enhanced UE identification information can reduce the likelihood that the communication device incorrectly determines, based on the provided identification information, that it is necessary to attempt to decode a signal sent using the indicated allocated resources.

[0080] In other words, the enhanced UE identification information can reduce the probability of false positive identification matching of the communication device.

[0081] Example embodiments of the present technology will be described in more detail with reference to the accompanying drawings.

[0082] Figure 6 A message sequence chart illustrating transmissions of the base station 101 and the communication devices 104a, 104b, 104c according to an embodiment of the present technique is shown.

[0083] Figure 6 The sequence in FIG. 6 starts from step S602, in which the third communication device 104c sends MsgA 650 to the base station 101 using a random access channel (RACH).

[0084] Incidentally, in step S604, the second communication device 104b transmits the second MsgA652 to the base station 101 using the random access channel. Likewise, in step S606, the first communication device 104a transmits the third MsgA654 to the base station 101.

[0085] exist Figure 6 In the embodiment, the random access transmissions in steps S602, S604, and S606 are shown as being separate and non-overlapping. However, in some embodiments, two or more of the steps may use the same RACH resources and / or may include the same random access preamble.

[0086] exist Figure 6 In the example of , each of the first MsgA transmission 650, the second MsgA transmission 652, and the third MsgA transmission 654 is received by the base station 101 and correctly decoded. Figure 6 In the example of , base station 101 determines that responses to first MsgA transmission 650 and third MsgA transmission 654 may be combined into a single MsgB 658. For example, both responses may refer to a 'successful' random access response ("successful RAR") message.

[0087] Accordingly, the base station 101 forms a first MsgB 658, which includes a first successful random access response 660 directed to the first communication device 104a and a second successful random access response 662 directed to the third communication device 104c. In step S608, the base station 101 sends a first downlink control information (DCI) 656, which includes an indication 664 of allocating downlink communication resources for the transmission of the first MsgB 658. The allocated communication resources can be located on a physical downlink shared channel (PDSCH). The DCI 656 can be sent using a physical downlink control channel (PDSCH). As indicated by arrow 690, the DCI 656 is sent in response to the first MsgA 650 and the third MsgA 654.

[0088] The DCI 656 may include an indication of a UE identity, which may not be unique and may be derived based on the communication resources used for the transmission of the first MsgA 650 and the third MsgA 654. For example, the first DCI 656 may be encoded using the MsgB-RNTI calculated according to the conventional techniques described above. As described above, in some embodiments, the condition for including both random access responses 660, 662 in the same MsgB 658 is that the parameters of the MsgA transmission used to determine the RNTI of the DCI 656 are the same for both the first MsgA 650 and the third MsgA 654.

[0089] Because both the first communication device 104a and the third communication device 104c derive the same identification, both the first communication device 104a and the third communication device 104c (correctly) believe that the first DCI 656 is addressed to them.

[0090] Subsequently, in step S610 , the base station 101 sends a first MsgB 658 including a first successful random access response 660 and a second successful random access response 662 using the resources indicated in the first DCI 656 .

[0091] If a second MsgA 652 is also sent using a communication resource whose parameters result in the first DCI 656 being encoded using the same MsgB-RNTI, it may be (incorrectly) determined that the first DCI 656 is addressed thereto and an attempt may be made to decode the first MsgB 658. However, as described above, it will be appreciated that, based on the absence of the temporary identity sent in the second MsgA 652, the success RAR contained therein is not addressed thereto.

[0092] exist Figure 6 In the example of , the base station 101 determines that the response to the second communication device 104b cannot be included in the first MsgB 656. That is, the base station 101 determines that the response to the second MsgA 652 sent in step S604 cannot be included in the first MsgB 658. This determination can be based on a determination that the response to the second MsgA 652 includes data that is reliably sent to the second communication device 104b. Accordingly, the base station 101 requests confirmation information from the second communication device 104b for the response sent by the base station 101 in response to the second MsgA 652.

[0093] As described above, in this case, the response to the second MsgA 652 may not be multiplexed with responses to other MsgAs such as the first MsgA 650 and the third MsgA 654. Therefore, as indicated by the dashed arrow 666, the base station 101 responds to the second MsgA 652 by sending a second DCI 668 in step S612, the second DCI 668 including an indication of the PDSCH resources 670, a UE identity 672 corresponding to the second communication device 104b, and a confirmation indication 674. Further details of the UE identity 672 are provided elsewhere in this description.

[0094] The confirmation indication 674 indicates to the second communication device 104b that the base station 101 is requesting to send confirmation information such as a positive confirmation (ACK) or a negative confirmation (NACK) to indicate the reception status of the MsgB sent using the communication resources indicated by the PDSCH resource indication 670. Further details of the confirmation indication 674 are described elsewhere in this description.

[0095] In step S614 , the base station 104 sends a second MsgB 676 including an RRC message 678 to the second communication device 104 b using the PDSCH communication resources indicated in the second DCI 668 .

[0096] Upon receiving the second DCI 668, the second communication device 104b determines to address it based on the UE identity 672. In response, it attempts to decode the second MsgB 676 sent in step S614 using the downlink communication resources indicated in the second DCI 668.

[0097] As indicated by the 'X' 680 in the message sequence diagram, the second communication device 104b is unable to correctly receive and decode the second MsgB 676. Therefore, in response to the acknowledgement indication 674 and the inability to receive and decode the transmission using the PDSCH resources indicated in the second DCI 668, at step S616, the second communication device 104b sends a negative acknowledgement (NACK) 682 to the base station 101. The NACK 682 may be sent using the physical uplink control channel PUCCH.

[0098] According to conventional acknowledgement techniques such as Hybrid Automatic Repeat Request (HARQ), at step S614 the second communication device 104b may store soft decoded bits corresponding to signals received on the allocated PDSCH communication resources indicated in the second DCI 668 .

[0099] In response to receiving NACK 682, base station 101 allocates further communication resources for retransmission of second MsgB 676. In step S618, base station 101 sends third DCI 684 including an indication of PDSCH resources for retransmission of second MsgB 676. In step S620, base station 101 sends retransmission 686 of second MsgB 676.

[0100] After transmitting in step S620, the second communication device 104b may retrieve the stored soft decoded bits stored after decoding the initial transmission of MsgB 676 in step S614. These soft decoded bits may be used together with the received decoded bits corresponding to the signal received using the PDSCH communication resources indicated in the third DCI 684 to increase the probability of successfully decoding the retransmitted MsgB 686.

[0101] exist Figure 6 In the example of , after step S620, the second communication device 104b successfully decodes the MsgB based on the retransmitted MsgB 686. The second communication device 104b can obtain the RRC message 678 from the decoded PDSCH resource. In addition, the communication device 104b can obtain one or more of its contention resolution identifier, C-RNTI, and timing advance (TA) from the decoded MsgB. At the second communication device 104b, the 2-step RACH procedure is completed.

[0102] In step S622 , in response to determining that MsgB has been successfully decoded, the second communication device 104 b sends a positive acknowledgement (ACK) 688 to the base station 101 .

[0103] In response to receiving the ACK 688, the base station 101 determines that the second communication device 104b has successfully received and decoded the contents of the MsgB 676 (retransmitted in the MsgB 676), and in response, refrains from further retransmissions of the scheduled data.

[0104] UE Identification

[0105] As described above, in some implementations, the UE identity 672 may be a MsgB-RNTI calculated based on the RACH resources used for transmission of the second MsgA 652 and for encoding the second DCI 668 in step S604 .

[0106] Alternatively, in some embodiments, the UE identifier 672 can be based on one or both of: a preamble index corresponding to a random access preamble used for transmission of the second MsgA 652; and an index corresponding to a DMRS (demodulation reference signal) port / sequence used by the communication device to send the data portion of the MsgA on an uplink shared resource (e.g., PUSCH).

[0107] For example, in some embodiments, the RNTI used to encode the second DCI 668 includes an enhanced MsgB-RNTI calculated based on one or more of a preamble index and a DMRS (demodulation reference signal) port / sequence index.

[0108] In some implementations, the enhanced MsgB-RNTI (MsgB-RNTI′) is calculated as follows:

[0109] MsgB-RNTI′=1+s_id+

[0110] 14×t_id+

[0111] 14×80×f_id+

[0112] 14×80×8×preamble_id+

[0113] 14×80×8×64×port_id+

[0114] 14×80×8×64×4×ul_carrier_id

[0115] Wherein, preamble_id is a random access preamble identifier or an index identifying the transmitted preamble (0<preamble_id<64), and port_id is an index associated with the DMRS port / sequence used for the PUSCH transmission portion of the MsgA transmission (0<port_id<4).

[0116] In this embodiment, the second communication device 104b monitors the downlink control channel for DCI transmission using the enhanced MsgB-RNTI. In addition, in some of these embodiments, the second communication device 104b monitors the downlink control channel for DCI transmission using the conventional MsgB-RNTI.

[0117] In some embodiments, when the DCI allocates resources for responses to multiple MsgAs, the DCI may include a UE identifier determined according to a first predetermined equation or rule, and wherein, when the DCI allocates resources for responses to a single MsgA, the DCI includes a UE identifier determined according to a second predetermined equation or rule. Preferably, when the UE identifier is determined according to the second equation or rule, the probability of determining the same UE identifier for multiple MsgA transmissions (so that multiple communication devices can determine that the DCI is in response to their corresponding MsgA transmissions) is lower than the probability determined according to the first equation or rule.

[0118] In some embodiments, the DCI may include a UE identifier, i.e., a value such as an RNTI within a first range when the DCI allocates resources in response to multiple MsgAs, and a value within a second range when the DCI allocates resources in response to a single MsgA.

[0119] In some embodiments, the UE identification 672 includes an indication of one or both of a preamble index and a DMRS (demodulation reference signal) port / sequence index within the body of the DCI.

[0120] For example, according to the conventional DCI format, there may be reserved bits (i.e., whose values ​​do not have any meaning in a particular version of the standard), such as defined in section 7.3.1.2.1 of [8]:

[0121] - Frequency domain resource allocation

[0122] - Time domain resource allocation - 4 bits as defined in subclause 5.1.2.1 of [9]

[0123] - VRB-to-PRB mapping - 1 bit according to Table 7.3.1.1.2-33

[0124] - Modulation and coding scheme - 5 bits as defined in subclause 5.1.3 of [9] using Table 5.1.3.1-1

[0125] - TB scaling - 2 bits as defined in subclause 5.1.3.2 of [9]

[0126] - Reserved bits - 16 bits

[0127] In some embodiments, one or more bits of a DCI payload such as conventional 'reserved' may include an indication of one or both of a preamble index and a DMRS (demodulation reference signal) port / sequence index.

[0128] In some implementations, another binary bit may be used to indicate the presence of one or more additional indexes.

[0129] For example, part of the payload could be specified as:

[0130] - Additional parameters: 1 bit (set to a first value indicating the presence of additional parameters and a second value indicating the absence of additional parameters);

[0131] -RAPID (Random Access Preamble Index) - 6 bits based on ra-preamble index

[0132] -DMRS port / sequence index - 2 bits

[0133] In some such embodiments, the RNTI used to encode the DCI may be based on the communication resource used for RACH transmissions, such as in a conventional MsgB-RNTI.

[0134] Because the enhanced MsgB-RNTI uses additional parameters, the possibility of collision when using the enhanced MsgB-RNTI is reduced. Similarly, when the above additional parameters are included in the payload of the DCI, the possibility of collision is reduced. That is, the probability that the communication device incorrectly determines that the DCI allocates communication resources for the response of its random access transmission is reduced. Accordingly, because it is not necessary to decode the MsgB sent using the allocated resources to determine that the MsgB does not include a response to its MsgA, the power consumption of the communication device is reduced.

[0135] Confirmation Instructions

[0136] In some embodiments, the confirmation indication 674 includes the presence of the UE identity 672 indicated in a predetermined manner. For example, the confirmation indication 674 may be implicitly indicated by encoding the DCI using the enhanced MsgB-RNTI described above. Alternatively, the presence of a field indicating one or both of the preamble index and the DMRS (demodulation reference signal) port / sequence index in the DCI payload may implicitly indicate the confirmation indication 674.

[0137] In some implementations, the confirmation indication 674 may be explicitly indicated within the DCI. For example, the confirmation indication 674 may correspond to setting an additional parameter indication within the DCI payload to a first predetermined value, or more generally, may correspond to setting one or more bits to a predetermined value indicating the presence of a confirmation indication.

[0138] In some embodiments, including the confirmation indication 674 includes encoding the DCI using an RNTI, wherein the RNTI is selected from a first range that is different from a second range used when the confirmation indication 674 is not present. In some embodiments, the enhanced MsgB-RNTI can be calculated (e.g., by using a predetermined bias) to ensure that it produces a value within the first range. In some embodiments, the first range refers to a range in which a regular MsgB-RNTI is located.

[0139] Including the confirmation indication in the resource allocation message (such as DCI) can enable a communication device that receives the resource allocation message but cannot decode the corresponding data sent in the resources allocated by the resource allocation message to know that the base station requests an indication (e.g., ACK / NACK) about the reception status of the data. Accordingly, NACK can be sent to indicate to the base station that retransmission is required.

[0140] Figure 7 A process flow diagram illustrating a process performed by a communication device according to an embodiment of the present technology.

[0141] Before starting the process, the communication device 104 determines that it needs to start transmission of uplink data according to a two-step procedure.

[0142] Figure 7 The process shown in FIG. 1 starts at S702, where the communication device selects a DMRS (demodulation reference signal) port / sequence for transmitting the data portion of MsgA on a shared uplink channel (e.g., PUSCH) as the first message in a two-step procedure. The process continues at step S704, where the communication device selects a random access preamble. At step S706, the communication device 104 selects a communication resource of a random access channel such as PRACH for transmitting the random access.

[0143] In step S708, the communication device 104 uses the selected RACH and PUSCH resources to send MsgA. MsgA includes the preamble selected in step S704 sent using the selected RACH resources and data sent using the PUSCH resources of the DMRS with the port / sequence parameters selected in step S702.

[0144] In step S710, the communication device 104 receives downlink control information (DCI) on the PDCCH. In step S712, the communication device 104 determines whether the DCI received in step S710 includes the RNTI corresponding to the MsgA sent in step S708 (referred to herein as a 'valid' RNTI). If not, control returns to step S710.

[0145] In some embodiments, the effective RNTI may be the conventional MsgB-RNTI described above, and in some embodiments, the effective RNTI may be the enhanced MsgB-RNTI described above.

[0146] In some embodiments, there may be multiple valid RNTI values ​​with which a response to a given MsgA transmission may be sent. That is, the base station 101 may send a response (RAR) to the communication device 104 using one of the multiple valid RNTI values. For example, if the RAR is sent in a MsgB that includes multiple RAR messages for multiple communication devices, a conventional MsgB-RNTI may be used. On the other hand, if the RAR is sent only to a single communication device, and / or if confirmation information is requested, an enhanced MsgB-RNTI may be used.

[0147] In some implementations, for example, if MsgA includes a C-RNTI, the C-RNTI may be a valid RNTI.

[0148] In step S712, if it is determined that the RNTI in the received DCI corresponds to the MsgA sent by the communication device 104 (ie, the RNTI is a valid RNTI), control proceeds to step S714.

[0149] In addition, in some embodiments, at step S712 (or after step S712), the communication device 104 may determine whether the parameters within the DCI identify the communication device 104. For example, as described above, the DCI may include additional parameters corresponding to the preamble and DMRS used for the MsgA transmission in step S708, such as the preamble index and / or the DMRS slot / sequence index, respectively. If the communication device determines that such parameters exist and they do not correspond to the MsgA sent in step S708, control may return to step S710. Specifically, in some embodiments, the communication device refrains from decoding signals received on the PDSCH communication resources indicated by the DCI received in step S710.

[0150] In step S714 , the communication device 104 decodes the signal received on the PDSCH communication resource indicated by the DCI received in step S710 .

[0151] In step S716, the communication device determines whether the DCI received in step S710 includes a confirmation indication. As described above, the confirmation indication may include the use of a specific RNTI value (such as an enhanced MsgB-RNTI), an implicit indication within the DCI payload (such as the presence of additional parameters), or an explicit indication within the DCI payload.

[0152] If there is no acknowledgement indication, the PDSCH is processed in a conventional manner in step S726. For example, the PDSCH signal may be decoded to determine whether the RACH procedure including the transmission of MsgA in step S708 was successful, or whether the RACH procedure generated a fallback procedure for a 4-step RACH procedure, or whether the RACH procedure failed.

[0153] In step S716, if it is determined that the DCI received in step S710 includes an acknowledgement indication, control proceeds to step S718. In step S718, it is determined whether the PDSCH signal received in step S714 is correctly and error-free decoded. If the PDSCH signal is correctly decoded, control proceeds to step S720, in which the communication device 104 sends a positive acknowledgement (ACK) message to the base station 101 and the process ends. In step S718, if it is determined that the PDSCH signal is not correctly decoded, control proceeds to step S722, in which the communication device 104 stores the soft bits generated by attempting PDSCH decoding in step S714. In step S724, the communication device 104 sends a negative acknowledgement (NACK) to the base station 101. Then, control can return to step S710 to monitor another DCI allocated downward in the communication resources for the retransmission of the random access response message.

[0154] Figure 8 A process of a base station, such as base station 101, is shown in accordance with an embodiment of the present technique.

[0155] The process starts from step S802, where the base station 101 receives MsgA transmitted by a communication device, such as the communication device 104. As described above, MsgA includes a part transmitted on the RACH and a part transmitted on the shared uplink resource (eg, PUSCH).

[0156] In response, at step S804, the base station 101 determines the content of the random access response and determines whether the response requires reliable delivery to the communication device 104. If so, control passes to step S806. If not, control passes to step S808.

[0157] In step S808, the base station 101 determines whether the random access response transmitted in response to the MsgA received in step S802 can be multiplexed with the random access response (RAR) to other MsgA received from other communication devices.

[0158] If not (eg, because there is no MsgA waiting for RAR transmission), control proceeds to step S812. If merging is possible, control proceeds to step S810.

[0159] In step S806, the base station 101 forms downlink control information including an indication of the downlink communication resource and an acknowledgement indication to indicate to the communication device 104 that acknowledgement information on data transmitted using the indicated downlink communication resource is to be transmitted.

[0160] The DCI formed in step S806 also includes a valid RNTI corresponding to the MsgA received in step S802. For example, the DCI may be the enhanced MsgB-RNTI described above. In some embodiments, the DCI includes an indication of additional parameters, such as a preamble index of the MsgA received in step S802 and / or a DMRS port / sequence index associated with a DMRS port / sequence parameter for transmission of the portion of the MsgA sent on the shared uplink channel. Multiple DMRS port / sequence indices may be associated with corresponding DMRS port / sequence parameters according to a predetermined association, e.g., as specified in the relevant 3GPP standard document, and the association may be known to both the communication device and the base station.

[0161] In some implementations, the confirmation indication includes the presence of additional parameters or the use of enhanced MsgB-RNTI.

[0162] Preferably, the RNTI (in combination with additional parameters, if included) makes it unlikely that two or more communications devices will both consider the DCI to have allocated resources for transmission in response to the respective communications devices' MsgA transmissions.

[0163] For example, after step S806, control proceeds to step S814 and DCI is sent using a downlink control channel such as PDCCH. Then, control proceeds to step S816, where MsgB including a random access response (RAR) to MsgA received in step S802 is sent using the communication resources indicated by the DCI sent in step S814.

[0164] Then, at step S818, the base station 101 monitors the communication resources associated with the uplink control channel for receiving the confirmation information sent by the communication device 104. At step S820, the base station 101 determines whether a positive confirmation has been received regarding the previous MsgB transmission. If a positive confirmation has been received, the process ends at step S822.

[0165] If a negative acknowledgement (or in some embodiments, no positive acknowledgement) is received at step S818, control passes to step S824 and MsgB is retransmitted. In general, the retransmission may be performed according to a conventional HARQ procedure. For example, the encoding may include puncturing that is different from the puncturing used in a previous (e.g., initial) transmission of MsgB. This encoding (or other encoding techniques) may be used to increase the probability that the communication device 104 can correctly decode MsgB using a combination of soft decoded bits generated for a previous transmission and soft decoded bits generated for the current retransmission.

[0166] After MsgB is retransmitted in step S824 , control returns to step 818 .

[0167] Returning to the steps after step S808, in steps S810 and S812, a DCI is formed, the DCI including communication resources allocated for transmission of an MsgB including a response to each of one (in step S810) or more (in step S812) MsgAs received by the base station 101. An acknowledgment indication is not included in the DCI.

[0168] At step S810, the base station forms a DCI using a UE identity that is valid for each MsgA whose response is sent in the allocated resources. For example, the UE identity may be a predetermined RA-RNTI or a conventional MsgB-RNTI.

[0169] Then, control passes to step S826, where DCI is sent, for example, using a control channel. Subsequently, at step S828, MsgB including multiple RARs (or a single RAR if step S828 is after step S812) is sent using the resources indicated in the DCI. Because the DCI does not include an acknowledgment indication, no acknowledgment information is sent in response to MsgB and the process then ends.

[0170] In step S812, the base station 101 forms a DCI using an RNTI that is valid for a single MsgA to which MsgB is a response. For example, in an embodiment in which the use of an enhanced MsgB-RNTI is not used as a confirmation indication as described in step S806, the UE identification used for the DCI may include an enhanced MsgB-RNTI. In other words, any suitable RNTI may be used provided that it does not implicitly indicate that a confirmation regarding the MsgB transmission is sent by the communication device. In some embodiments, the UE identification may include the inclusion of additional parameters in the DCI payload provided that the additional parameters included in the embodiment are not themselves the confirmation indication used in step S806.

[0171] The use of enhanced MsgB-RNTI and / or other additional parameters, or more generally, the use of more accurate identification within the DCI, can reduce power consumption of another communication device. This is because the other communication device can determine that the DCI does not allocate resources for an MsgB transmission including a response to its MsgA and can thereby refrain from attempting to decode the MsgB transmission. The use of additional parameters can reduce the probability that a generated DCI incorrectly appears (to another communication device) to indicate that a following MsgB includes a response to its MsgA.

[0172] As described above, after step S812, control proceeds to step S826.

[0173] Thus, in some embodiments, using more specifically targeted identification information in the DCI increases the probability that a communication device to which MsgB is not addressed will not attempt to decode MsgB.

[0174] Additionally or alternatively, in some embodiments, including an acknowledgment indication in the DCI ensures that acknowledgment information is sent by the communication device to which MsgB is directed, even if the communication device cannot successfully decode MsgB, thereby enabling reliable delivery of data to the communication device.

[0175] In some embodiments, a more targeted identification information itself is used to refer to the confirmation indication (or a portion thereof), thereby being able to identify confirmation indications that preferably only include MsgB including a single RAR (directed to a single communication device), thereby providing an effective means for reliably delivering data to a single communication device.

[0176] In some embodiments, Figure 7 and Figure 8 In the processes shown, one or more steps may be reordered, modified, or omitted.

[0177] For example, in some embodiments, the Figure 8 In the process of step S808 and step S812, and control can be directly passed from step S804 to step S812, in which case, whether or not MsgB includes one or more RARs, DCI can be transmitted in a substantially similar manner. In this embodiment, for each transmission of MsgA providing its RAR, the RNTI used to encode the DCI must be valid. For example, the DCI can be a predetermined RA-RNTI.

[0178] It should be understood that Figure 7 and Figure 8 The process in may include further steps not shown, such as RACH fallback procedure, RACH failure procedure (which may include Figure 7The process may further include a state change of the communication device, such as a transition from an idle or deactivated state to a connected state.

[0179] same, Figure 6 The message sequence diagram in is used for the purpose of clearly describing various aspects of the present technology. In some embodiments, the Figure 6 One or more steps, messages or communication means shown in , and there may be additional steps, messages or communication means. For example, Figure 6 The MsgA transmission is shown as a single RACH transmission; for simplicity, the portion of the MsgA sent on the PUSCH is not shown.

[0180] Thus, a method for operating a communication device in a wireless communication network is described, the method comprising: sending a random access message on a wireless access interface, the random access message comprising a selected random access preamble and a transmission on a shared channel, the shared channel transmission using a demodulation reference signal (DMRS) according to one or more selected DMRS parameters; receiving a resource allocation message, the resource allocation message comprising an indication of sending a resource allocation message in response to the random access message and an indication of allocating downlink communication resources for the transmission of a random access response message; receiving a signal sent using the allocated downlink communication resources; determining that the resource allocation message identifies the communication device; and in response to determining that the resource allocation message identifies the communication device, decoding a signal sent using the allocated downlink communication resources; wherein the resource allocation message comprises an indication of identifying the communication device based on an index associated with the selected random access preamble and one or more of the selected one or more DMRS parameters.

[0181] Also disclosed is a method for operating a communication device in a wireless communication network, the method comprising: sending a random access message including a selected random access preamble code; receiving a resource allocation message, the resource allocation message including: an indication of sending a resource allocation message in response to the random access message; an indication of allocating downlink communication resources for the transmission of a random access response message; a confirmation indication, the confirmation indication requesting the communication device to send confirmation information to indicate the reception status of the random access response message; and an indication of identifying the communication device; receiving a signal sent using the allocated downlink communication resources, the signal representing data; determining that the resource allocation message identifies the communication device; in response to determining that the resource allocation message identifies the communication device, decoding the signal sent using the allocated downlink communication resources to determine the reception status of the data; and in response to receiving the resource allocation message including the confirmation indication, sending confirmation information based on the determined reception status.

[0182] Therefore, a corresponding communication device, a base station and a method as well as a circuit for a communication device and a circuit for a base station are also described.

[0183] It should be understood that although the present disclosure focuses in some aspects on implementations based on LTE and / or 5G networks for the purpose of providing specific examples, the same principles can be applied to other wireless telecommunication systems. Thus, even though the terminology used herein is generally the same or similar to that of the LTE and 5G standards, the teachings are not limited to current versions of LTE and 5G and can be equally applied to any suitable arrangement that is not based on LTE or 5G and / or is compatible with any other further versions of LTE, 5G or other standards.

[0184] It should be noted that the various example schemes discussed herein may rely on information that is predetermined / predefined in a sense known to both the base station and the communication device. It should be understood that, in general, the predetermined / predefined information can be established by, for example, a definition in an operating standard of a wireless telecommunication system, or in a previously exchanged signaling between a base station and a communication device (e.g., in a system information signaling), or associated with a radio resource control setting signaling, or in information stored in a SIM application. That is, the specific manner in which the relevant predefined information is established and shared between the various elements of the wireless telecommunication system does not have a primary significance for the operating principles described herein. It should be further noted that the various example schemes discussed herein rely on information exchanged / communicated between the various elements of the wireless telecommunication system, and it should be understood that, for example, in terms of a specific signaling protocol and the type of communication channel used, the communication can generally be performed according to conventional techniques, unless otherwise limited by the context. That is, the specific manner in which the relevant information is exchanged between the various elements of the wireless telecommunication system does not have a primary significance for the operating principles described herein.

[0185] It should be understood that the principles described herein are not only applicable to a specific type of communication device, but are more generally applicable to any type of communication device. For example, the scheme is not limited to URLLC / IIoT devices or other low-latency communication devices, but is more generally applicable to any type of communication device that operates, for example, using a wireless link to a communication network.

[0186] It should be further understood that the principles described herein are applicable not only to LTE-based or 5G / NR-based wireless telecommunication systems, but also to any type of wireless telecommunication system that supports dynamic scheduling of shared communication resources.

[0187] Further particular and preferred aspects of the invention are set out in the accompanying independent and dependent claims. It will be appreciated that features of the dependent claims may be combined with features of the independent claims other than those explicitly set out in the claims.

[0188] Thus, the above discussion only discloses and describes exemplary embodiments of the present invention. As will be appreciated by those skilled in the art, the present invention can be implemented in other specific forms without departing from its essence or essential features. Accordingly, the disclosure of the present invention is intended to be illustrative, rather than limiting, the scope of the present invention and other claims. The present disclosure, including any easily distinguishable variations taught herein, partially defines the scope of the above-mentioned claimed terms so that the subject of the invention is not dedicated to the public.

[0189] The corresponding features of the present disclosure are defined by the following numbered paragraphs:

[0190] Paragraph 1. A method for operating a communication device in a wireless communication network, the method comprising: sending a random access message on a wireless access interface, the random access message comprising a selected random access preamble and a transmission on a shared channel, the shared channel transmission using a demodulation reference signal (DMRS) according to one or more selected DMRS parameters; receiving a resource allocation message, the resource allocation message comprising an indication of sending a resource allocation message in response to the random access message and an indication of allocating downlink communication resources for transmission of a random access response message; receiving a signal sent using the allocated downlink communication resources; determining that the resource allocation message identifies the communication device; and in response to determining that the resource allocation message identifies the communication device, decoding a signal sent using the allocated downlink communication resources; wherein the resource allocation message comprises an indication of identifying the communication device based on an index associated with the selected random access preamble and one or more of the selected one or more DMRS parameters.

[0191] Paragraph 2. A method according to paragraph 1, wherein the resource allocation message identifies the communication device at least in part by a radio network temporary identity used to encode the resource allocation message.

[0192] Paragraph 3. A method according to paragraph 2, wherein the wireless access interface is based on orthogonal frequency division multiplexing (OFDM) and provides a physical random access channel (PRACH) on an uplink carrier; a random access message is sent using time and frequency communication resources corresponding to the timing of the PRACH; and a radio network temporary identifier is determined based on one or more of the following: an index of the first OFDM symbol of the PRACH timing; an index of the first time slot of the PRACH timing in the system frame; subcarrier spacing; an index of the PRACH timing in the frequency domain; and the uplink carrier used.

[0193] Paragraph 4. A method according to paragraph 2 or paragraph 3, wherein the radio network temporary identity is determined based on one or more of the selected random access preamble index and an index associated with the selected one or more DMRS parameters.

[0194] Paragraph 5. A method according to any of paragraphs 1 to 4, wherein the resource allocation message includes an indication of one or more of an index associated with the selected random access preamble and an index associated with the selected one or more DMRS parameters.

[0195] Paragraph 6. A method according to any one of paragraphs 1 to 5, the method comprising: receiving a second resource allocation message; determining that the second resource allocation message does not identify the communication device; and in response to the determination, suppressing decoding of a signal received using a downlink communication resource allocated by the second resource allocation message.

[0196] Paragraph 7. A method for operating a communication device in a wireless communication network, the method comprising: sending a random access message including a selected random access preamble code; receiving a resource allocation message, the resource allocation message including: an indication of sending a resource allocation message in response to the random access message; an indication of allocating downlink communication resources for the transmission of a random access response message; a confirmation indication, the confirmation indication requesting the communication device to send confirmation information to indicate the reception status of the random access response message; and an indication of identifying the communication device; receiving a signal sent using the allocated downlink communication resources, the signal representing data; determining that the resource allocation message identifies the communication device; in response to determining that the resource allocation message identifies the communication device, decoding the signal sent using the allocated downlink communication resources to determine the reception status of the data; and in response to receiving the resource allocation message including the confirmation indication, sending confirmation information based on the determined reception status.

[0197] Paragraph 8. A method according to paragraph 7, wherein when the decoding is unsuccessful, the confirmation information indicates that the data was not correctly received.

[0198] Paragraph 9. A method according to paragraph 7 or paragraph 8, wherein when decoding is successful, the confirmation information indicates that the data was correctly received.

[0199] Paragraph 10. According to the method of paragraph 8 or paragraph 9, the method includes: determining that the data is not successfully decoded; in response to receiving a resource allocation message including a confirmation indication and determining that the data is not successfully decoded, storing soft decoded bits obtained by decoding the data; receiving a signal representing a retransmission of the data; and decoding the data based on the stored soft decoded bits and the received signal representing the retransmission of the data.

[0200] Paragraph 11. A method according to any of paragraphs 7 to 10, wherein the resource allocation message includes a temporary identifier, and the temporary identifier includes a confirmation indication.

[0201] Paragraph 12. The method of Paragraph 11, wherein when the temporary identifier includes an acknowledgement indication, the temporary identifier is within a first range of values; and when the temporary identifier does not include an acknowledgement indication, the temporary identifier is within a second range of values.

[0202] Paragraph 13. A method according to paragraph 11 or paragraph 12, wherein the random access message includes a transmission on a shared channel, the shared channel transmission uses a demodulation reference signal (DMRS) based on one or more selected DMRS parameters; and the temporary identifier is determined based on an index associated with the random access preamble code and one or more of the indices associated with the selected one or more DMRS parameters.

[0203] Paragraph 14. A method according to paragraph 13, wherein, when the temporary identifier includes an acknowledgment indication, the temporary identifier is determined based on a preamble index and one or more of an index associated with one or more selected DMRS parameters; and when the temporary identifier does not include an acknowledgment indication, the temporary identifier is not based on the preamble index or an index associated with one or more selected DMRS parameters.

[0204] Paragraph 15. According to any of paragraphs 7 to 14, the confirmation indication includes an indication of the presence of one or more of a preamble index and an index associated with the selected one or more DMRS parameters in the resource allocation message.

[0205] Paragraph 16. A method according to any of paragraphs 7 to 15, wherein the confirmation indication comprises one or more bits set to a predetermined value.

[0206] Paragraph 17. A method according to any of paragraphs 7 to 16, wherein the data includes radio resource control (RRC) signaling.

[0207] Paragraph 18. A method according to any one of paragraphs 7 to 17, wherein the selected one or more DMRS parameters include one or more of an antenna port and a modulation sequence.

[0208] Paragraph 19. A method for operating a base station in a wireless communication network, the method comprising: receiving a random access message sent by a communication device; determining that data that needs to be reliably transmitted will be included in a random access response message; in response to determining that data that needs to be reliably transmitted to the communication device will be included in a response to the random access message, forming a resource allocation message, the resource allocation message comprising: a confirmation indication requesting that confirmation information be sent by the communication device to indicate a reception status of the random access response message; an indication of allocating downlink communication resources for the transmission of the random access response message; and an indication of identifying the communication device; sending a resource allocation message; and sending a random access response message using the allocated downlink communication resources, the random access response message including data that needs to be reliably transmitted.

[0209] Paragraph 20. The method of Paragraph 19, wherein the resource allocation message includes a temporary identifier, and the temporary identifier includes an acknowledgement indication.

[0210] Paragraph 21. The method of Paragraph 20, wherein when the temporary identifier includes an acknowledgement indication, the temporary identifier is within a first range of values; and when the temporary identifier does not include an acknowledgement indication, the temporary identifier is within a second range of values.

[0211] Paragraph 22. A method according to paragraph 20 or paragraph 21, wherein the random access message includes a transmission on a shared channel, the shared channel transmission uses a demodulation reference signal (DMRS) based on one or more selected DMRS parameters; and the temporary identifier is determined based on a preamble code index of the random access message and one or more of the indices associated with the selected one or more DMRS parameters.

[0212] Paragraph 23. A method according to paragraph 22, wherein, when the temporary identifier includes an acknowledgment indication, the temporary identifier is determined based on a preamble index and one or more of an index associated with one or more selected DMRS parameters; and when the temporary identifier does not include an acknowledgment indication, the temporary identifier is not based on the preamble index or an index associated with one or more selected DMRS parameters.

[0213] Paragraph 24. A method according to any of paragraphs 19 to 23, wherein the confirmation indication includes an indication of the presence of one or more of a preamble index and an index associated with the selected one or more DMRS parameters in the resource allocation message.

[0214] Paragraph 25. A method according to any of paragraphs 19 to 24, wherein the confirmation indication comprises one or more bits set to a predetermined value.

[0215] Paragraph 26. A method according to any one of paragraphs 19 to 25, the method comprising: receiving confirmation information; and when the confirmation information indicates that the data is not correctly decoded, retransmitting the data.

[0216] Paragraph 27. A method according to any of paragraphs 19 to 25, wherein the data includes radio resource control (RRC) signaling.

[0217] Paragraph 28. A method for operating a base station in a wireless communication network, the method comprising: receiving a random access message on a wireless access interface, the random access message comprising a selected random access preamble and a transmission on a shared channel, the shared channel transmission using a demodulation reference signal (DMRS) according to one or more selected DMRS parameters; determining that a response message to be sent comprises a response to the random access message and does not include a response to any other random access message; in response to receiving the random access message and determining that the response message comprises a response to the random access message and does not include a response to any other random access message, forming a resource allocation message, the resource allocation message comprising: an indication that the resource allocation message responds to the random access message; an indication that downlink communication resources are allocated for transmission of the random access response message; and an indication that a communication device is identified based on an index associated with the selected random access preamble and one or more of the selected one or more DMRS parameters; sending a resource allocation message; and sending a response message using the allocated downlink communication resources.

[0218] Paragraph 29. A method according to paragraph 28, wherein the resource allocation message identifies the communication device at least in part by a radio network temporary identity used to encode the resource allocation message.

[0219] Paragraph 30. A method according to paragraph 29, wherein the wireless access interface is based on orthogonal frequency division multiplexing (OFDM) and provides a physical random access channel (PRACH) on an uplink carrier; a random access message is sent using time and frequency communication resources corresponding to the timing of the PRACH; and the radio network temporary identifier is determined based on one or more of the following: the index of the first OFDM symbol of the PRACH timing; the index of the first time slot of the PRACH timing in the system frame; the subcarrier spacing; the index of the PRACH timing in the frequency domain; and the uplink carrier used.

[0220] Paragraph 31. A method according to paragraph 29 or paragraph 30, wherein the radio network temporary identity is determined based on one or more of the selected random access preamble index and an index associated with the selected one or more DMRS parameters.

[0221] Paragraph 32. A method according to any of paragraphs 28 to 31, wherein the resource allocation message includes an indication of one or more of an index associated with the selected random access preamble and an index associated with the selected one or more DMRS parameters.

[0222] Paragraph 33. A communication device for operating in a wireless communication network, the communication device comprising: a transmitter configured to send a signal via a wireless access interface provided by a base station of the wireless communication network; a receiver configured to receive a signal via the wireless access interface; and a controller configured to control the transmitter and the receiver so that the communication device is operable to: send a random access message on the wireless access interface, the random access message comprising a selected random access preamble and a transmission on a shared channel, the shared channel transmission using a demodulation reference signal (DMRS) according to one or more selected DMRS parameters; receive a resource allocation message, the resource allocation message comprising an indication of sending a resource allocation message in response to the random access message and an indication of allocating downlink communication resources for transmission of a random access response message; receive a signal sent using the allocated downlink communication resources; determine that the resource allocation message identifies the communication device; and in response to determining that the resource allocation message identifies the communication device, decode the signal sent using the allocated downlink communication resources; wherein the resource allocation message comprises an indication of identifying the communication device based on an index associated with the selected random access preamble and one or more of the selected one or more DMRS parameters.

[0223] Paragraph 34. A circuit for a communication device operating in a wireless communication network, the circuit comprising: a transmitter circuit configured to send a signal via a wireless access interface provided by a base station of the wireless communication network; a receiver circuit configured to receive a signal via the wireless access interface; and a controller circuit configured to control the transmitter circuit and the receiver circuit so that the communication device is operable to: send a random access message on the wireless access interface, the random access message comprising a selected random access preamble and a transmission on a shared channel, the shared channel transmission using a demodulation reference signal (DMRS) according to one or more selected DMRS parameters; receive a resource allocation message, the resource allocation message comprising an indication to send a resource allocation message in response to the random access message and an indication to allocate downlink communication resources for transmission of a random access response message; receive a signal sent using the allocated downlink communication resources; determine that the resource allocation message identifies the communication device; and in response to determining that the resource allocation message identifies the communication device, decode the signal sent using the allocated downlink communication resources; wherein the resource allocation message comprises an indication to identify the communication device based on an index associated with the selected random access preamble and one or more of the selected one or more DMRS parameters.

[0224] Paragraph 35. A communication device for operating in a wireless communication network, the communication device comprising: a transmitter configured to send a signal via a wireless access interface provided by a base station of the wireless communication network; a receiver configured to receive a signal via the wireless access interface; and a controller configured to control the transmitter and the receiver so that the communication device is operable to: send a random access message including a selected random access preamble code; receive a resource allocation message, the resource allocation message including: an indication of sending a resource allocation message in response to the random access message; an indication of allocating downlink communication resources for the transmission of a random access response message; a confirmation indication requesting that confirmation information be sent by the communication device to indicate a reception status of the random access response message; and an indication of identifying the communication device; receiving a signal sent using the allocated downlink communication resource, the signal representing data; determining that the resource allocation message identifies the communication device; in response to determining that the resource allocation message identifies the communication device, decoding a signal sent using the allocated downlink communication resource to determine a reception status of the data; and in response to receiving the resource allocation message including the confirmation indication, sending confirmation information based on the determined reception status.

[0225] Paragraph 36. A circuit for a communication device operating in a wireless communication network, the circuit comprising: a transmitter circuit configured to send a signal via a wireless access interface provided by a base station of the wireless communication network; a receiver circuit configured to receive a signal via the wireless access interface; and a controller circuit configured to control the transmitter circuit and the receiver circuit so that the communication device is operable to: send a random access message including a selected random access preamble; receive a resource allocation message, the resource allocation message including: an indication to send a resource allocation message in response to the random access message; an indication to allocate downlink communication resources for transmission of a random access response message; a confirmation indication requesting that confirmation information be sent by the communication device to indicate a reception status of the random access response message; and an indication to identify the communication device; receive a signal sent using the allocated downlink communication resource, the signal representing data; determine that the resource allocation message identifies the communication device; in response to determining that the resource allocation message identifies the communication device, decode the signal sent using the allocated downlink communication resource to determine a reception status of the data; and in response to receiving the resource allocation message including the confirmation indication, send confirmation information based on the determined reception status.

[0226] Paragraph 37. A base station for use in a wireless communication network, the base station providing a wireless access interface for communicating with a communication device, the base station comprising: a transmitter configured to send a signal to the communication device via the wireless access interface; a receiver configured to receive a signal from the communication device; and a controller configured to control the transmitter and the receiver so that the base station is operable to: receive a random access message sent by the communication device; determine that data that needs to be reliably transmitted will be included in a random access response message; in response to determining that data that needs to be reliably transmitted to the communication device will be included in a response to the random access message, form a resource allocation message, the resource allocation message comprising: a confirmation indication requesting that confirmation information be sent by the communication device to indicate a reception status of the random access response message; an indication of allocating downlink communication resources for the transmission of the random access response message; and an indication of identifying the communication device; sending a resource allocation message; and sending a random access response message using the allocated downlink communication resources, the random access response message including data that needs to be reliably transmitted.

[0227] Paragraph 38. A circuit for a base station used in a wireless communication network, the base station providing a wireless access interface for communicating with a communication device, the circuit comprising: a transmitter circuit configured to send a signal to the communication device via the wireless access interface; a receiver circuit configured to receive a signal from the communication device; and a controller circuit configured to control the transmitter circuit and the receiver circuit so that the base station is operable to: receive a random access message sent by the communication device; determine that data that needs to be reliably transmitted will be included in a random access response message; in response to determining that data that needs to be reliably transmitted to the communication device will be included in a response to the random access message, form a resource allocation message, the resource allocation message comprising: a confirmation indication requesting that confirmation information be sent by the communication device to indicate a reception status of the random access response message; an indication of allocating downlink communication resources for the transmission of the random access response message; and an indication of identifying the communication device; sending a resource allocation message; and sending a random access response message using the allocated downlink communication resources, the random access response message including data that needs to be reliably transmitted.

[0228] Paragraph 39. A base station for use in a wireless communication network, the base station providing a wireless access interface for communicating with a communication device, the base station comprising: a transmitter configured to send a signal to the communication device via the wireless access interface; a receiver configured to receive a signal from the communication device; and a controller configured to control the transmitter and the receiver so that the base station is operable to: receive a random access message on the wireless access interface, the random access message comprising a selected random access preamble and a transmission on a shared channel, the shared channel transmission using a demodulation reference signal (DMRS) according to one or more selected DMRS parameters; determine a response message to be sent comprising a response to the random access message; A method of transmitting a random access message comprising: transmitting a resource allocation message to a user of the communication device and determining that the response message includes a response to the random access message and does not include a response to any other random access message; in response to receiving the random access message and determining that the response message includes a response to the random access message and does not include a response to any other random access message, forming a resource allocation message, the resource allocation message comprising: an indication that the resource allocation message is in response to the random access message; an indication that downlink communication resources are allocated for transmission of the random access response message; and an indication that a communication device is identified based on an index associated with the selected random access preamble and one or more of the selected one or more DMRS parameters; sending the resource allocation message; and sending the response message using the allocated downlink communication resources.

[0229] Paragraph 40. A circuit for a base station used in a wireless communication network, the base station providing a wireless access interface for communicating with a communication device, the circuit comprising: a transmitter circuit configured to transmit a signal to the communication device via the wireless access interface; a receiver circuit configured to receive a signal from the communication device; and a controller circuit configured to control the transmitter circuit and the receiver circuit so that the base station can be operated to: receive a random access message on the wireless access interface, the random access message comprising a selected random access preamble and a transmission on a shared channel, the shared channel transmission using a demodulation reference signal (DMRS) according to one or more selected DMRS parameters; determine a response message packet to be sent The invention relates to a method for transmitting a random access message to a wireless communication device, wherein the resource allocation message includes a response to a random access message and does not include a response to any other random access message; in response to receiving the random access message and determining that the response message includes a response to the random access message and does not include a response to any other random access message, forming a resource allocation message, the resource allocation message including: an indication that the resource allocation message is responsive to the random access message; an indication that downlink communication resources are allocated for transmission of the random access response message; and an indication that the communication device is identified based on an index associated with the selected random access preamble and one or more of the selected one or more DMRS parameters; sending the resource allocation message; and sending the response message using the allocated downlink communication resources.

[0230] Further particular and preferred aspects of the invention are set out in the accompanying independent and dependent claims. It will be appreciated that features in the dependent claims may be combined with features of the independent claims other than as explicitly set out in a claim.

[0231] References

[0232] [1] RP-182090, "Revised SID: Study on NR Industrial Internet of Things (IoT)," 3GPP RAN#81.

[0233] [2]Holma H.and Toskala A, "LTE for UMTS OFDMA and SC-FDMA based radioaccess", John Wiley and Sons, 2009.

[0234] [3]3GPP TS 38.321, "Medium Access Control (MAC) protocol specification (Rel-15)", vl5.3.0.

[0235] [4]3GPP TS 38.300 V15.4.0.

[0236] [5]3GPP TS 38.321 "NR; Medium Access Control (MAC) protocol specification", version 15.6.0.

[0237] [6] 3GPP Tdoc Rl-1907323 "Procedure for cross-slot scheduling technique", Ericsson.

[0238] [7]ETSI TS 136213 V13.0.0(2016-01) / 3GPP TS 36.212version 13.0.0Release 13.

[0239] [8]3GPP TS 38.212 "NR; Multiplexing and channel coding", version 15.6.0.

[0240] [9]3GPP TS 38.214“NR;Physical layer procedures for data”,version15.6.0.

[0241]

[10] 3GPP document RP-182894,“WID:2-step RACH for NR,”RAN#82.

[0242]

[11] 3GPP document RP-182878,“NR-based Access to Unlicensed Spectrum”,RAN#82.

[0243]

[12] 3GPP TS 38.211“NR;Physical channels and modulation”,version15.6.0.

Claims

1. A method for operating a communication device in a wireless communication network, the method comprising: Sending a random access message on a wireless access interface, the random access message comprising a selected random access preamble and a transmission on a shared channel, the transmission on the shared channel using a DMRS according to one or more selected demodulation reference signal DMRS parameters; receiving a resource allocation message, the resource allocation message comprising an indication to send the resource allocation message in response to the random access message and an indication to allocate downlink communication resources for transmission of a random access response message; receiving a signal transmitted using the allocated downlink communication resources; determining that the resource allocation message identifies the communications device; and In response to determining that the resource allocation message identifies the communication device, decoding the signal sent using the allocated downlink communication resources; wherein, The wireless access interface is based on orthogonal frequency division multiplexing OFDM and provides a physical random access channel PRACH on an uplink carrier; Sending the random access message using time and frequency communication resources corresponding to a PRACH opportunity; and The resource allocation message includes an indication identifying the communication device at least in part by a radio network temporary identity used to encode the resource allocation message, the radio network temporary identity being based on: The index of the first OFDM symbol of the PRACH opportunity; An index of the first time slot of the PRACH opportunity in the system frame; Subcarrier spacing; An index of the PRACH opportunity in the frequency domain; The uplink carrier used; an index associated with the selected random access preamble; and An index associated with the selected one or more DMRS parameters.

2. The method according to claim 1, comprising: receiving a second resource allocation message; determining that the second resource allocation message does not identify the communications device; and In response to the determination, decoding of signals received using the downlink communications resources allocated by the second resource allocation message is refrained.

3. A method of operating a base station in a wireless communication network, the method comprising: receiving a random access message on a wireless access interface, the random access message comprising a selected random access preamble and a transmission on a shared channel, the transmission on the shared channel using a DMRS according to one or more selected demodulation reference signal DMRS parameters; determining that the response message to be sent includes a response to the random access message and does not include a response to any other random access message; in response to receiving the random access message and determining that the response message includes a response to the random access message and does not include a response to any other random access message, forming a resource allocation message, sending the resource allocation message; and The response message is sent using the allocated downlink communication resources, wherein the wireless access interface is based on orthogonal frequency division multiplexing OFDM and provides a physical random access channel PRACH on an uplink carrier, and the random access message is sent using time and frequency communication resources corresponding to the PRACH opportunity; and the resource allocation message includes: The resource allocation message is responsive to an indication of the random access message; an indication of allocation of downlink communication resources for transmission of a random access response message; and The indication of the communication device is identified at least in part by a radio network temporary identity used to encode the resource allocation message, the radio network temporary identity being based on: The index of the first OFDM symbol of the PRACH opportunity; An index of the first time slot of the PRACH opportunity in the system frame; Subcarrier spacing; An index of the PRACH opportunity in the frequency domain; The uplink carrier used; an index associated with the selected random access preamble; and An index associated with the selected one or more DMRS parameters.

4. A communication device for operating in a wireless communication network, the communication device comprising: a transmitter configured to transmit a signal via a wireless access interface provided by a base station of the wireless communication network; a receiver configured to receive a signal via the wireless access interface; as well as A controller is configured to control the transmitter and the receiver so that the communication device can operate as follows: Sending a random access message on the wireless access interface, the random access message comprising the selected random access preamble and a transmission on a shared channel, the transmission on the shared channel using a DMRS according to the selected one or more demodulation reference signal DMRS parameters; receiving a resource allocation message, the resource allocation message comprising an indication to send the resource allocation message in response to the random access message and an indication to allocate downlink communication resources for transmission of a random access response message; receiving a signal transmitted using the allocated downlink communication resources; determining that the resource allocation message identifies the communications device; and In response to determining that the resource allocation message identifies the communication device, decoding the signal sent using the allocated downlink communication resources; wherein, The wireless access interface is based on orthogonal frequency division multiplexing OFDM and provides a physical random access channel PRACH on an uplink carrier; Sending the random access message using time and frequency communication resources corresponding to a PRACH opportunity; and The resource allocation message includes an indication identifying the communication device at least in part by a radio network temporary identity used to encode the resource allocation message, the radio network temporary identity being based on: The index of the first OFDM symbol of the PRACH opportunity; An index of the first time slot of the PRACH opportunity in the system frame; Subcarrier spacing; An index of the PRACH opportunity in the frequency domain; The uplink carrier used; an index associated with the selected random access preamble; and An index associated with the selected one or more DMRS parameters.

5. A circuit for a communication device operating in a wireless communication network, the circuit comprising: a transmitter circuit configured to transmit a signal via a wireless access interface provided by a base station of the wireless communication network; a receiver circuit configured to receive a signal via the wireless access interface; as well as a controller circuit configured to control the transmitter circuit and the receiver circuit so that the communication device can operate as follows: Sending a random access message on the wireless access interface, the random access message comprising the selected random access preamble and a transmission on a shared channel, the transmission on the shared channel using a DMRS according to the selected one or more demodulation reference signal DMRS parameters; receiving a resource allocation message, the resource allocation message comprising an indication to send the resource allocation message in response to the random access message and an indication to allocate downlink communication resources for transmission of a random access response message; receiving a signal transmitted using the allocated downlink communication resources; determining that the resource allocation message identifies the communications device; and In response to determining that the resource allocation message identifies the communication device, decoding the signal sent using the allocated downlink communication resources; wherein, The wireless access interface is based on orthogonal frequency division multiplexing OFDM and provides a physical random access channel PRACH on an uplink carrier; Sending the random access message using time and frequency communication resources corresponding to a PRACH opportunity; and The resource allocation message includes an indication identifying the communication device at least in part by a radio network temporary identity used to encode the resource allocation message, the radio network temporary identity being based on: The index of the first OFDM symbol of the PRACH opportunity; An index of the first time slot of the PRACH opportunity in the system frame; Subcarrier spacing; An index of the PRACH opportunity in the frequency domain; The uplink carrier used; an index associated with the selected random access preamble; and An index associated with the selected one or more DMRS parameters.

6. A base station for use in a wireless communication network, the base station providing a wireless access interface for communicating with a communication device, the base station comprising: a transmitter configured to send a signal to the communication device via the wireless access interface; a receiver configured to receive a signal from the communication device; as well as A controller is configured to control the transmitter and the receiver so that the base station can operate as follows: receiving a random access message on the wireless access interface, the random access message comprising a selected random access preamble and a transmission on a shared channel, the transmission on the shared channel using a DMRS according to one or more selected demodulation reference signal (DMRS) parameters; determining that the response message to be sent includes a response to the random access message and does not include a response to any other random access message; in response to receiving the random access message and determining that the response message includes a response to the random access message and does not include a response to any other random access message, forming a resource allocation message, sending the resource allocation message; and The response message is sent using the allocated downlink communication resources, wherein the wireless access interface is based on orthogonal frequency division multiplexing OFDM and provides a physical random access channel PRACH on an uplink carrier, and the random access message is sent using time and frequency communication resources corresponding to the PRACH opportunity; and the resource allocation message includes: The resource allocation message is responsive to an indication of the random access message; an indication of allocation of downlink communication resources for transmission of a random access response message; and an indication of identifying the communication device at least in part by a radio network temporary identity used to encode the resource allocation message, the radio network temporary identity being based on: The index of the first OFDM symbol of the PRACH opportunity; An index of the first time slot of the PRACH opportunity in the system frame; Subcarrier spacing; An index of the PRACH opportunity in the frequency domain; The uplink carrier used; an index associated with the selected random access preamble; and An index associated with the selected one or more DMRS parameters.

7. A circuit for a base station used in a wireless communication network, the base station providing a wireless access interface for communicating with a communication device, the circuit comprising: a transmitter circuit configured to transmit a signal to the communication device via the wireless access interface; a receiver circuit configured to receive a signal from the communication device; as well as a controller circuit configured to control the transmitter circuit and the receiver circuit so that the base station can operate as follows: receiving a random access message on the wireless access interface, the random access message comprising a selected random access preamble and a transmission on a shared channel, the transmission on the shared channel using a DMRS according to one or more selected demodulation reference signal (DMRS) parameters; determining that the response message to be sent includes a response to the random access message and does not include a response to any other random access message; in response to receiving the random access message and determining that the response message includes a response to the random access message and does not include a response to any other random access message, forming a resource allocation message, sending the resource allocation message; and The response message is sent using the allocated downlink communication resources, wherein the wireless access interface is based on orthogonal frequency division multiplexing OFDM and provides a physical random access channel PRACH on an uplink carrier, and the random access message is sent using time and frequency communication resources corresponding to the PRACH opportunity; and the resource allocation message includes: The resource allocation message is responsive to an indication of the random access message; an indication of allocation of downlink communication resources for transmission of a random access response message; and an indication of identifying the communication device at least in part by a radio network temporary identity used to encode the resource allocation message, the radio network temporary identity being based on: The index of the first OFDM symbol of the PRACH opportunity; An index of the first time slot of the PRACH opportunity in the system frame; Subcarrier spacing; An index of the PRACH opportunity in the frequency domain; The uplink carrier used; an index associated with the selected random access preamble; and An index associated with the selected one or more DMRS parameters.

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