Patent Description:
Examples of mobile or wireless telecommunication systems may include the Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (UTRAN), Long Term Evolution (LTE) Evolved UTRAN (E-UTRAN), LTE-Advanced (LTE-A), MulteFire, LTE-A Pro, and/or fifth generation (<NUM>) radio access technology or new radio (NR) access technology. <NUM> wireless systems refer to the next generation (NG) of radio systems and network architecture. <NUM> is mostly built on a new radio (NR), but a <NUM> (or NG) network can also build on E-UTRA radio. It is estimated that NR may provide bitrates on the order of <NUM>-<NUM> Gbit/s or higher, and may support at least enhanced mobile broadband (eMBB) and ultra-reliable low-latency-communication (URLLC) as well as massive machine type communication (mMTC). NR is expected to deliver extreme broadband and ultra-robust, low latency connectivity and massive networking to support the Internet of Things (IoT). With IoT and machine-to-machine (M2M) communication becoming more widespread, there will be a growing need for networks that meet the needs of lower power, low data rate, and long battery life. It is noted that, in <NUM>, the nodes that can provide radio access functionality to a user equipment (i.e., similar to Node B in UTRAN or eNB in LTE) may be named gNB when built on NR radio and may be named NG-eNB when built on E-UTRA radio.

<CIT> (D1) relates to facilitating indication of a primary or an alternative beam (or, multiple beams) in random RACH resources for beam management. According to D <NUM>, signaling and/or transmission protocols are provided to facilitate enhanced initial beam management procedure by indicating one or more alternative DL transmission beams from the BS device to the mobile device during the RACH procedure.

As defined by claim <NUM>, the invention provides a method, comprising: receiving, by a user equipment and from a primary transmit receive point, a message; transmitting, by the user equipment and to the primary transmit receive point, an indication of a capability to receive a multi-transmit receive point transmission of a message <NUM> of a random access procedure, wherein the indication is a physical random access channel preamble; receiving, by the user equipment and from the primary transmit receive point, a random access response in a message <NUM> of the random access procedure based on transmitting the indication of the capability, wherein the random access response is configured to allocate resources for transmission of information on at least one additional beam, and wherein the random access response comprises at least one field to signal a command to indicate the at least one additional beam in a message <NUM> of the random access procedure; and transmitting, by the user equipment and to the primary transmit receive point, in the message <NUM> of the random access procedure, at least one index of the at least one additional beam after receiving the random access response. Preferred embodiments of the method of claim <NUM> are defined by claims <NUM> to <NUM>.

As defined by claim <NUM>, the invention provides a method, comprising: receiving, by a primary transmit receive point, an indication of a capability of a user equipment to receive a multi-transmit receive point transmission of a message <NUM> of a random access procedure, wherein the indication is a physical random access channel preamble; transmitting, by the primary transmit receive point, a random access response in a message <NUM> of the random access procedure based on receiving the indication of the capability, wherein the random access response is configured to allocate resources for transmission of information on at least one additional beam, and wherein the random access response comprises at least one field configured to signal a command to indicate the at least one additional beam in a message <NUM> of the random access procedure; and receiving, by the primary transmit receive point and in the message <NUM>, at least one index of the at least one additional beam after transmitting the random access response. Preferred embodiments of the method of claim <NUM> are defined by claims <NUM> to <NUM>.

As defined by claim <NUM>, the invention provides a user equipment apparatus comprising means for: receiving, from a primary transmit receive point, a message; transmitting, to the primary transmit receive point, an indication of a capability to receive a multi-transmit receive point transmission of a message <NUM> of a random access procedure, wherein the indication is a physical random access channel preamble; receiving, from the primary transmit receive point, a random access response in a message <NUM> of the random access procedure based on transmitting the indication of the capability, wherein the random access response is configured to allocate resources for transmission of information on at least one additional beam, and wherein the random access response comprises at least one field to signal a command to indicate the at least one additional beam in a message <NUM> of the random access procedure; and transmitting, to the primary transmit receive point, in the message <NUM> of the random access procedure, at least one index of the at least one additional beam after receiving the random access response.

As defined by claim <NUM>, the invention provides a primary transmit receive point apparatus comprising means for: receiving an indication of a capability of a user equipment to receive a multi-transmit receive point transmission of a message <NUM> of a random access procedure, wherein the indication is a physical random access channel preamble; transmitting a random access response in a message <NUM> of the random access procedure based on receiving the indication of the capability, wherein the random access response is configured to allocate resources for transmission of information on at least one additional beam, and wherein the random access response comprises at least one field configured to signal a command to indicate the at least one additional beam in a message <NUM> of the random access procedure; and receiving, in the message <NUM>, at least one index of the at least one additional beam after transmitting the random access response.

It will be readily understood that the components of certain example embodiments, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of some example embodiments of systems, methods, apparatuses, and computer program products for controlling operations of a transmit receive point (TRP) and/or a user equipment (UE), is not intended to limit the scope of certain embodiments but is representative of selected example embodiments.

Additionally, if desired, the different functions or steps discussed below may be performed in a different order and/or concurrently with each other. Furthermore, if desired, one or more of the described functions or steps may be optional or may be combined. As such, the following description should be considered as merely illustrative of the principles and teachings of certain example embodiments, and not in limitation thereof.

Early Data Transmission (EDT) was first introduced in LTE-M and narrow band Internet of Things (NB-IoT) in Rel-<NUM>. In Rel-<NUM>, mobile-originated (MO) EDT was specified. EDT enables data transfer between network entity (e.g., a gNB) and a UE during a random access procedure without a need for the UE to go into connected mode. In Rel-<NUM>, UL data transmission in a message <NUM> (Msg3) of the random access procedure for MO EDT was specified for eMTC and NB-IoT.

With respect to NB-IoT, such a technology is likely to target requirements extending beyond what can be supported with LTE-based loT technologies. The use cases for such a technology include not only massive machine-type communications (MTC) but also industrial applications with more stringent reliability and latency requirements. It is also possible that frequency range <NUM> (FR2) (millimeter wave (mmWave)) will also be used in non-public networks, particularly in industry environments, because of new spectrum opportunities and potential advantages with isolating deployments at such frequencies. It is expected that features such as EDT that are useful for transfer of small amounts of data with low overhead and latency will also be needed.

Multi-transmit receive point (TRP) transmission may be part of new radio (NR) multiple input, multiple output (MIMO) enhancements. Historically, such an approach has been used to enhance the user data rate. However, the approach is also being used to improve reliability and latency for ultra-reliable low-latency communication (URLLC) transmission. Future enhancements may focus on techniques for the radio resource control (RRC) connected state.

One of the main challenges associated with mmWave deployments is signal blockage. Due to the high attenuation experienced by signals at these frequencies, movement of the user device or other objects in the line of sight with the TRP can cause the signal strength to drop suddenly at the device (e.g., UE). When the network has data for the device, it pages the device. If the amount of data is small, the data may be sent via EDT with low latency. If signal blockage occurs during the data transfer, then the data is not received (either in Msg2 or Msg4).

As such, signal blockage can affect reliability and latency of data sent on MT EDT. For instance, when the UE does not receive the random access response (RAR) (e.g., Msg2) within the RAR window, the UE would reinitiate the random access procedure. Therefore, a delay is incurred in the delivery of data. If the data is carried in Msg4 and the Msg4 is blocked, the UE would fail to transmit an acknowledgment. This would prompt the network entity to attempt a retransmission of Msg4, and a delay is incurred in the delivery of data.

It should be noted that one of ordinary skill in the art would understand that a contention based random access procedure typically comprises four steps, for example, as described in Section <NUM>. <NUM> and illustrated in Figure <NUM>. <NUM>-<NUM>, in 3GPP TS <NUM>. The messages transmitted in the four steps may be respectively referred to as message <NUM> (or Msg1), message <NUM> (or Msg2), message <NUM> (or Msg3), and message <NUM> (Msg4). Msg1 may consist of a preamble transmitted in a physical random access channel (PRACH) and Msg2. The response to Msg1 may be transmitted in Msg2 as the random access response (RAR). Msg3 and Msg4, which may be transmitted in the subsequent steps, may resolve any contention among multiple UEs for access to the PRACH that may occur in the first step. Further details on the random access procedure and the different messages may be found in 3GPP TS <NUM> and 3GPP TS <NUM>.

Some embodiments described herein may provide for improving reliability of mobile-terminated (MT) early data transmission (EDT). For example, some embodiments described herein may provide signaling support to enable EDT on multiple beams from different TRPs or the same TRP. When the UE is paged, it follows a modified EDT procedure as described herein. Some embodiments described herein may provide a network with information on additional beams that the UE has measured. The network can then choose to use this information to perform EDT. In this way, some embodiments described herein may improve reliability and latency of MT EDT, thereby improving communications between a UE (e.g., similar to apparatus <NUM> in <FIG>) and at least one TRP (e.g., similar to apparatus <NUM> in <FIG>). Therefore, certain example embodiments provide several technological improvements, enhancements, and/or advantages over existing technological processes.

<FIG> illustrates an example signaling diagram of a procedure, according to some embodiments described herein. <FIG> shows operations that use an indication of additional beam information in a Msg3 for multi-TRP transmission on Msg4. As shown in <FIG>, the example signaling diagram includes a UE <NUM> (e.g., similar to apparatus <NUM> in <FIG>) and a network entity (e.g., similar to apparatus <NUM> in <FIG>, such as a gNB <NUM>). A network entity may include one or more TRPs, and communication may be, more specifically, between the UE <NUM> and one or more TRPs of the network entity.

Prior to the operations shown in <FIG>, the UE <NUM> may measure at least one synchronization signal and physical broadcast channel block (SSB) beam from multiple TRPs to determine at least one particular beam from each TRP. For example, the UE <NUM> may determine at least one particular beam from each TRP based on signal quality measurements, such as signal-to-noise ratio (SNR), reference signal received power (RSRP), reference signal received quality (RSRQ), and/or the like. If each TRP has a separate cell ID, the UE <NUM> may differentiate between TRPs from the SSBs. Otherwise, if SSBs are distributed across multiple TRPs, TRP IDs associated with different SSB groups may be used to differentiate different TRPs. In some embodiments, the UE <NUM> may determine a maximum of N strongest beams where N is fixed in the specification.

As shown at <NUM>, the UE <NUM> may receive, from a primary TRP of the gNB <NUM>, at least one paging message (or a control message, in some embodiments). In some embodiments, the at least one paging message may trigger a random access procedure. As shown at <NUM>, the UE <NUM> may transmit at least one random access preamble (a physical random access channel (PRACH) preamble) to the primary TRP of the gNB <NUM>. For example, the UE <NUM> may transmit at least one PRACH preamble based on a particular beam (e.g., a strongest beam or a beam with a highest quality) from the primary TRP (e.g., in a PRACH occasion mapped to the SSB).

In some embodiments, the at least one PRACH preamble may indicate a capability of the UE <NUM> to receive a multi-TRP transmission of a Msg4 of the random access procedure. For example, the UE <NUM> may indicate a capability to receive a multi-TRP transmission of Msg4 via selection of a particular PRACH preamble. In some embodiments, a pool of PRACH preambles may be reserved for use by UEs <NUM> with this capability.

As shown at <NUM>, the primary TRP of the gNB <NUM> may transmit a Msg2 to the UE <NUM>. In some embodiments, the Msg2 may include a random access response (RAR). In some embodiments, a new RAR may be used for the UE <NUM>. The RAR may allocate resources for transmission of information on one or more additional beams in Msg3 of the random access procedure. In some embodiments, the number of additional beams M to be indicated may be fixed or may be indicated in the RAR (e.g., with <NUM> bits or with another quantity of bits). In addition to legacy fields, one or more new fields for additional beam indication may be included in the RAR. In some embodiments, the RAR may include at least one field to signal a command to indicate at least one additional beam.

As shown at <NUM>, the UE <NUM> may transmit a Msg3 to the primary TRP of the gNB <NUM>. In some embodiments, the UE <NUM> may indicate additional beam information in the Msg3. For example, the UE <NUM> may indicate one or more indices of a predetermined number M of additional SSB beams corresponding to a same TRP associated with the particular beam (e.g., strongest or highest quality) or to different TRPs. In some embodiments, the UE <NUM> may indicate M additional SSB beams without knowing if the SSB beams correspond to the same TRP as the originally indicated particular beam (e.g., strongest or highest quality) or to different TRPs. If the one or more additional SSB beams correspond to the same TRP as the particular beam (e.g., strongest or highest quality), the primary TRP can ignore this information and schedule single-TRP Msg4 transmission using a legacy approach. Alternatively, if transmission from multiple beams at the same TRP can be supported, the TRP can schedule Msg4 transmission on multiple beams from the same TRP.

In some embodiments, the primary TRP may schedule multi-TRP transmission of a Msg4. For example, the primary TRP may schedule the multi-TRP transmission after receiving the Msg3 from the UE <NUM>. In some embodiments, the primary TRP may transmit a physical downlink control channel (PDCCH) transmission to the UE <NUM>. In some embodiments, the PDCCH transmission may indicate whether the Msg4 will be transmitted from a single TRP or from multiple TRPs (e.g., the multiple TRPs may be determined based on a beam indicated in the Msg3). In some embodiments, the PDCCH transmission may be transmitted from multiple TRPs.

As shown at <NUM>, the primary TRP of the gNB <NUM> may transmit, to the UE <NUM>, MT EDT on the Msg4 of the random access procedure. For example, the primary TRP may transmit the MT EDT on the Msg4 after transmitting a RAR to the UE <NUM>. In some embodiments, the MT EDT on the Msg4 is transmitted from multiple TRPs (e.g., using a multi-TRP transmission scheme for a physical downlink shared channel (PDSCH)). For example, PDSCH from different TRPs can use space division multiplexing (SDM), time division multiplexing (TDM), or frequency division multiplexing (FDM). In some embodiments, at least one demodulation reference signal (DMRS) associated with the PDSCH is quasi-collocated with at least one UE-indicated SSB.

In this way, some embodiments described with respect to <FIG> may use a modified RAR that includes allocation for additional information in Msg3. In addition, some embodiments may use an indication of one or more additional SSB beams from other TRPs in Msg3.

As described above, <FIG> is provided as an example. Embodiments are not limited to the example of <FIG>.

<FIG> illustrates an example signaling diagram of a procedure, according to some embodiments described herein. <FIG> shows operations that use an indication of additional beam information in dedicated physical uplink shared channel (PUSCH) for multi-TRP transmission on a Msg2 or a Msg4 for a two-step random access channel (RACH) procedure. As shown in <FIG>, the example signaling diagram includes a UE <NUM> (e.g., similar to apparatus <NUM> in <FIG>) and a network entity (e.g., similar to apparatus <NUM> in <FIG>, such as a gNB <NUM>). The network entity may include one or more TRPs, and communication may be, more specifically, between the UE <NUM> and one or more TRPs of the gNB <NUM>.

As shown at <NUM>, a primary TRP of the gNB <NUM> may transmit at least one paging message (or at least one control message, in some embodiments) to the UE <NUM>. In some embodiments, the at least one paging message sent by the primary TRP to the UE <NUM> may indicate at least one location with reference to at least one PRACH occasion where at least one short PUSCH resource (e.g., for at least one MsgA of at least one random access procedure) containing additional beam information can be sent. In some embodiments, a paging message may indicate a number of additional beams that the UE <NUM> needs to indicate. In some embodiments, at least one resource indication associated with the paging message may indicate at least one size and/or at least one frequency location of the at least one PUSCH resource. In some embodiments, a size of a PUSCH resource may be fixed so that only location information needs to be indicated. For the primary TRP to know which UE <NUM> supports this capability, an access and mobility management function (AMF) may need to maintain the information identifying that UE <NUM> is capable and configured for multi-TRP reception.

In some embodiments, the at least one paging message may include information that identifies at least one dedicated PRACH preamble for transmitting a MsgA. Additionally, or alternatively, the at least one paging message may include information that identifies at least one PUSCH transmission following the at least one dedicated PRACH preamble that is configured to indicate one or more additional beams. Additionally, or alternatively, the at least one paging message may include information that identifies at least one delay from at least one PRACH occasion for indicating the one or more additional beams.

As shown at <NUM>, the UE <NUM> may transmit at least one MsgA to the primary TRP of the gNB <NUM>. For example, the UE <NUM> may transmit the at least one MsgA after receiving the at least one paging message. In some embodiments, the UE <NUM> may transmit the at least one MsgA using the at least one dedicated PRACH preamble.

As shown at <NUM>, the UE <NUM> may transmit additional beam information to the primary TRP of the gNB <NUM>. For example, the UE <NUM> may transmit the additional beam information using the at least one PUSCH resource allocated in the at least one paging message received from the primary TRP. In some embodiments, the measurement and indication of one or more additional beams (e.g., one or more SSB beams) may be similar to that described above in connection with <FIG>, with the difference being that the information may be sent to the primary TRP in MsgA instead of Msg3.

As shown at <NUM>, the UE <NUM> may receive MT EDT after transmitting the at least one MsgA to the primary TRP. For example, the UE <NUM> may receive the MT EDT on a beam indicated by the UE <NUM>. In some embodiments, the MT EDT may be received in at least one Msg2 or at least one Msg4 of the at least one random access procedure. If the MT EDT is transmitted in a Msg2, the Msg2 may be transmitted from multiple TRPs. If the MT EDT is transmitted in a Msg4, the Msg4 may be transmitted from multiple TRPs, after receiving a Msg3 from the UE, in a manner similar to the operations described with respect to <FIG>.

In this way, some embodiments described with respect to <FIG> may use at least one resource indication in at least one paging message for indication of additional beam information in at least one PRACH occasion. In addition, some embodiments may use at least one indication of one or more additional SSB beams from other TRPs in at least one MsgA.

<FIG> illustrates an example signaling diagram of a procedure, according to some embodiments described herein. <FIG> shows operations that use a preamble mapping to a set of beams for multi-TRP transmission in a Msg2 or a Msg4. As shown in <FIG>, the example signaling diagram includes a UE <NUM> (e.g., similar to apparatus <NUM> in <FIG>) and a network entity (e.g., similar to apparatus <NUM> in <FIG>, such as a gNB <NUM>). A network entity may include one or more TRPs, and communication may be, more specifically, between the UE <NUM> and one or more TRPs of the gNB <NUM>.

In some embodiments, prior to other operations described herein, a primary TRP of the gNB <NUM> may reserve a pool of preambles for mapping to multiple beams. For example, these preambles may be reserved from a PRACH pool and may belong to each of the SSBs.

As shown at <NUM>, the primary TRP of the gNB <NUM> may transmit at least one paging message (or at least one control message, in some embodiments) to the UE <NUM>. In some embodiments, the at least one paging message may comprise information identifying a set of PRACH preambles. When the at least one paging message is sent to the UE <NUM>, the at least one paging message may indicate multiple preambles from at least one reserved pool, with each of the preambles mapping to a set of beams of the serving cells. For example, in the case of N beams and M preambles, each preamble may map to N/M beams. When the UE <NUM> receives the at least one paging message, the UE <NUM> may select a PRACH pool corresponding to a SSB. Within a PRACH pool, the UE <NUM> may select the preamble for transmission from a list of contention free preambles provided to the UE <NUM>.

For this selection, the UE <NUM> may use one or more beam measurements, and may assign at least one preamble that most suits the UE <NUM>'s idle mode beam measurements (e.g., that has a highest relative strength or quality to other beam options). In some embodiments, the UE <NUM> may measure the beams over all the sets and may determine the closest preamble corresponding to particular set of measured beams (e.g., strongest or highest quality) and/or one or more other sets of measured beams (e.g., the second strongest or highest quality set of beams, the third strongest or highest quality set of beams, etc.). If the last connected beam is known to the UE <NUM> and the primary TRP, then the preamble selected may correspond to the set of beams containing the last known beam.

In some embodiments, the UE <NUM> may determine at least one mapping, from the at least one paging message or from system information, of each of the set of PRACH preambles to at least one of the SSB beams on which the UE <NUM> determines to receive at least one multi-TRP transmission. Each preamble in the pool may be mapped to a set of SSB beams. The mapping between a particular preamble index to a group of beams may be provided via system information or the at least one paging message. In some embodiments, the beams in a set may be transmitted from the same TRP or the beams may be transmitted from different TRPs (e.g., when the SSB beams are distributed over multiple TRPs).

As shown at <NUM>, the UE <NUM> may transmit at least one random access preamble (e.g., at least one PRACH preamble of at least one random access procedure) to the primary TRP of the gNB <NUM>. The UE <NUM> may transmit the at least one random access preamble on at least one PRACH occasion. The at least one PRACH occasion may map to a particular SSB beam (e.g., strongest or highest quality) within a set of SSB beams. In some embodiments, if the UE <NUM> does not receive an RAR, the UE <NUM> may transmit at least one other preamble (e.g., at least one preamble corresponding to a second strongest or highest quality SSB beam within the set of SSB beams). In some embodiments, if an RAR is not received, the UE <NUM> may transmit at least one preamble corresponding to the set of SSB beams.

As shown at <NUM>, the primary TRP of the gNB <NUM> may transmit, to the UE <NUM>, MT EDT on a Msg2 or a Msg <NUM> of the random access procedure. For example, the gNB <NUM> may transmit the MT EDT after receiving the PRACH preamble from the UE <NUM>.

In this way, some embodiments described with respect to <FIG> include use of an indication of multiple dedicated preamble indices with the paging message. As described above, the indices may be chosen from the PRACH pool corresponding to a detected SSB. In addition, some embodiments use a mapping of a set of SSB beams, from which the UE <NUM> determines to receive a multi-TRP transmission, to each of the dedicated PRACH preamble indices within the PRACH pool for the SSBs. In addition, some embodiments may use an indication of PRACH preambles (each mapped to multiple beams) in a MsgA or a Msg1 of a random access procedure.

<FIG> illustrates an example flow diagram of a method, according to some embodiments described herein. For example, <FIG> illustrates example operations of a UE (e.g., similar to apparatus <NUM> in <FIG>). The operations may be similar to some operations shown in <FIG>.

In an embodiment, the method includes, at <NUM>, receiving, from a primary transmit receive point (TRP), a paging message (or a control message, in some embodiments). For example, the UE may receive the paging message from a primary TRP. In an embodiment, the method includes, at <NUM>, transmitting, to the primary TRP, an indication of a capability to receive a multi-TRP transmission of a message <NUM> of a random access procedure. For example, the UE may transmit the indication to the TRP after receiving the paging message. The indication is a physical random access channel (PRACH) preamble.

In an embodiment, the method includes, at <NUM>, receiving, from the primary TRP, a random access response (RAR) in a message <NUM> of the random access procedure based on transmitting the indication of the capability. For example, the UE may receive the RAR message in a message <NUM> (e.g., Msg2) after transmitting the indication of the capability. The RAR is configured to allocate resources for transmission of information on at least one additional beam. The RAR comprises at least one field to signal a command to indicate the at least one additional beam in a message <NUM> (e.g., Msg3) of the random access procedure. In an embodiment, the method includes, at <NUM>, transmitting, to the primary TRP, in the message <NUM> of the random access procedure, at least one index of the at least one additional beam after receiving the RAR. For example, the UE may transmit the at least one index after receiving the RAR in the message <NUM>.

In some embodiments, the method may include performing, prior to transmitting the indication, at least one measurement of synchronization signal and physical broadcast channel block (SSB) beams from multiple TRPs, and determining a beam for each of the multiple TRPs based on the at least one measurement. In some embodiments, the multiple TRPs may be differentiated based on: at least one cell identifier, of the SSB beams, corresponding to the multiple TRPs, or at least one TRP identifier corresponding to different groups of SSB beams. In some embodiments, the method may include receiving a paging message triggering the random access procedure, and transmitting the indication based on a SSB beam received from the primary TRP.

In some embodiments, the indication may be selected from multiple indices or reserved preambles, and the multiple indices or reserved preambles may be different reserved PRACH preambles. In some embodiments, the at least one index may correspond to at least one TRP other than the primary TRP. In some embodiments, the method may include receiving a physical downlink control channel (PDCCH) transmission after transmitting the message <NUM>. The PDCCH transmission may indicate whether a message <NUM> of the random access procedure will be transmitted from a single TRP or from multiple TRPs. The multiple TRPs may be determined based on the at least one additional beam indicated in the message <NUM>.

In some embodiments, the method may include receiving mobile terminated (MT) early data transmission (EDT) on a message <NUM> of the random access procedure after transmitting the message <NUM>. The message <NUM> may be communicated based on a multi-TRP transmission scheme for a physical downlink shared channel (PDSCH). At least one demodulation reference signal (DMRS) associated with the PDSCH may be quasi-collocated with at least one UE-indicated SSB.

<FIG> illustrates an example flow diagram of a method, according to some embodiments described herein. For example, <FIG> shows example operations of a TRP (e.g., similar to, or of, apparatus <NUM> of <FIG>). The method illustrated in <FIG> may be similar to some operations shown in <FIG>.

In an embodiment, the method includes, at <NUM>, receiving, by a primary transmit receive point (TRP), an indication of a capability of a user equipment (UE) to receive a multi-TRP transmission of a message <NUM> of a random access procedure. For example, a primary TRP may receive an indication of a capability from a UE. The indication is a physical random access channel (PRACH) preamble.

In an embodiment, the method includes, at <NUM>, transmitting, by the primary TRP, a random access response (RAR) in a message <NUM> of the random access procedure based on receiving the indication of the capability. For example, the primary TRP may transmit, to the UE, an RAR in a message <NUM> (e.g., Msg2) after receiving the indication. The RAR is configured to allocate resources for transmission of information on at least one additional beam. The RAR comprises at least one field configured to signal a command to indicate the at least one additional beam in a message <NUM> of the random access procedure.

In an embodiment, the method includes, at <NUM>, receiving, by the primary TRP and in the message <NUM>, at least one index of the at least one additional beam after transmitting the RAR. For example, the primary TRP may receive, from the UE, at least one index after transmitting the RAR.

In some embodiments, the method may include transmitting a paging message (or a control message, in some embodiments) triggering the random access procedure, and receiving the indication based on a SSB beam. In some embodiments, the indication may be selected from multiple indices or reserved preambles, and the multiple indices or reserved preambles may be different reserved PRACH preambles. In some embodiments, the at least one index may correspond to a single TRP or to multiple TRPs.

In some embodiments, the method may include determining that the at least one additional beam corresponds to the single TRP, determining to ignore the at least one index based on the at least one additional beam corresponding to the single TRP, and scheduling: a single-TRP message <NUM> transmission after determining to ignore the at least one index, or a message <NUM> transmission on multiple beams from the single TRP. In some embodiments, the method may include transmitting a physical downlink control channel (PDCCH) transmission after transmitting the RAR. The PDCCH transmission may be configured to indicate whether a message <NUM> of the random access procedure will be transmitted from a single TRP or from multiple TRPs, and the multiple TRPs may be determined based on the at least one additional beam indicated in the message <NUM>.

In some embodiments, the method may include transmitting MT EDT on a message <NUM> of the random access procedure after receiving the RAR. The message <NUM> may be transmitted with at least one TRP. The message <NUM> may be communicated based on a multi-TRP transmission scheme for a physical downlink shared channel (PDSCH). At least one demodulation reference signal (DMRS) may be quasi-collocated with at least one UE-indicated SSB.

<FIG> illustrates an example flow diagram of a method, according to some embodiments described herein. For example, <FIG> illustrates example operations of a UE (e.g., similar to apparatus <NUM> of <FIG>), similar to some operations shown in <FIG>.

In an embodiment, the method may include, at <NUM>, receiving, from a primary transmit receive point (TRP), a paging message (or a control message, in some embodiments). For example, a UE may receive the paging message from a primary TRP. In some embodiments, the paging message may comprise information identifying: a resource indication configured to indicate at least one of a size and a frequency location of a physical uplink shared channel (PUSCH) resource for a message A (e.g., MsgA) of a random access procedure and for indicating at least one additional beam in the random access procedure, and a delay from a physical random access channel (PRACH) occasion for the indicating.

In some embodiments, the method may include, at <NUM>, transmitting, to the primary TRP, the message A after receiving the paging message. For example, the UE may transmit the message A after receiving the paging message. In some embodiments, the message A may be transmitted using a PRACH preamble followed by an indication of the at least one additional beam in the PUSCH resource.

In some embodiments, the paging message may further comprise information identifying a number of additional strong beams that a user equipment (UE) is to indicate. In some embodiments, a size and frequency location of the PUSCH resource may be fixed. In some embodiments, the method may include performing a measurement of a strongest synchronization signal and physical broadcast channel (PBCH) block (SSB) beam and of the at least one additional SSB beam. In some embodiments, the method may include receiving, from at least the primary TRP, mobile terminated (MT) early data transmission (EDT) after transmitting the message A of the random access procedure. The MT EDT may be received in a message <NUM> or a message <NUM> of the random access procedure.

<FIG> illustrates an example flow diagram of a method, according to some embodiments described herein. For example, <FIG> illustrates example operations of a TRP (e.g., similar to, or of, apparatus <NUM> of <FIG>), similar to some operations shown in <FIG>.

In an embodiment, the method may include, at <NUM>, transmitting, by the primary TRP, a paging message (or a control message, in some embodiments). For example, a primary TRP may transmit a paging message to a UE. In some embodiments, the paging message may comprise information identifying: a resource indication configured to indicate at least one of a size and a frequency location of a physical uplink shared channel (PUSCH) resource for a message A (e.g., MsgA) of a random access procedure and for indicating at least one additional beam in the random access procedure. In an embodiment, the method may include, at <NUM>, receiving the message A after transmitting the paging message. For example, the primary TRP may receive the message A from the UE after transmitting the paging message. In some embodiments, the message A may be transmitted using the physical random access channel (PRACH) preamble followed by an indication of the at least one additional beam in the PUSCH resource.

In some embodiments, the paging message may further comprise information identifying a number of additional strong beams that a user equipment (UE) is to indicate. In some embodiments, a size and frequency location of the PUSCH resource may be fixed. In some embodiments, the method may include transmitting, on multiple beams or with at least one other TRP, mobile terminated (MT) early data transmission (EDT) after receiving the message A of the random access procedure. The MT EDT may be transmitted in a message <NUM> or a message <NUM> of the random access procedure.

<FIG> illustrates an example flow diagram of a method, according to some embodiments described herein. For example, <FIG> shows example operations of a UE (e.g., similar to apparatus <NUM> of <FIG>). The method illustrated in <FIG> may be similar to some operations shown in <FIG>.

In an embodiment, the method may include, at <NUM>, receiving, from a primary transmit receive point (TRP), a paging message (or a control message in some embodiments). For example, a UE may receive a paging message from a primary TRP. In an embodiment, the method may include, at <NUM>, determining a mapping, from the paging message or system information, of each of a set of reserved physical random access channel (PRACH) preambles to at least one of multiple SSB beams on which a user equipment (UE) determines to receive a multi-TRP transmission. For example, the UE may determine the mapping after receiving the paging message.

In an embodiment, the method may include, at <NUM>, transmitting a PRACH preamble of a random access procedure. For example, the UE may transmit a PRACH preamble after determining the mapping. In some embodiments, the PRACH preamble may have been selected from the set of reserved PRACH preambles based on at least one beam measurement of the SSB beams and the mapping.

In some embodiments, the paging message may indicate a subset of the set of reserved PRACH preambles that map to a set of SSB beams associated with the TRP. The mapping may be indicated in the system information. In some embodiments, the set of reserved PRACH preambles may be associated with at least one SSB beam and at least one TRP.

In some embodiments, the method may include performing at least one measurement of the SSB beams, and identifying at least one SSB beam, of the SSB beams, to indicate to the TRP based on the at least one measurement. In some embodiments, the method may include transmitting the PRACH preamble on a PRACH occasion that corresponds to a SSB beam from the primary TRP within a set of SSB beams. In some embodiments, the method may include receiving, from at least the primary TRP, mobile terminated (MT) early data transmission (EDT) on a message <NUM> or a message <NUM> of the random access procedure after transmitting the PRACH preamble.

<FIG> illustrates an example flow diagram of a method, according to some embodiments described herein. For example, <FIG> illustrates example operations of a primary TRP (e.g., similar to apparatus <NUM> of <FIG>). The method illustrated in <FIG> may be similar to some operations shown in <FIG>.

In an embodiment, the method may include, at <NUM>, transmitting, by a primary transmit receive point (TRP), a paging message (or a control message, in some embodiments). For example, a primary TRP may transmit a paging message to a UE. In an embodiment, the method may include, at <NUM>, receiving a physical random access channel (PRACH) preamble of a random access procedure. For example, the primary TRP may receive a PRACH preamble from the UE after transmitting the paging message. In some embodiments, the PRACH preamble may identify at least one selected SSB beam from the SSB beams.

In some embodiments, the paging message may further comprise information identifying a mapping between the set of PRACH preambles and the corresponding SSB beams. In some embodiments, the paging message may indicate a subset of a set of reserved PRACH preambles that map to a set of SSB beams associated with the TRP. The mapping may be indicated in system information. In some embodiments, the set of reserved PRACH preambles may be associated with at least one SSB beam and at least one TRP. In some embodiments, the method may include receiving the PRACH preamble on a PRACH occasion that corresponds to a SSB beam within a set of SSB beams. In some embodiments, the method may include transmitting mobile terminated (MT) early data transmission (EDT) on a message <NUM> or a message <NUM> of the random access procedure after transmitting the PRACH preamble.

<FIG> illustrates an example of an apparatus <NUM> according to an embodiment. In an embodiment, apparatus <NUM> may be a node, host, or server in a communications network or serving such a network. For example, apparatus <NUM> may be a network node, satellite, base station, a Node B, an evolved Node B (eNB), <NUM> Node B or access point, next generation Node B (NG-NB or gNB), a TRP, and/or a WLAN access point, associated with a radio access network, such as a LTE network, <NUM> or NR. For example, apparatus <NUM> may correspond to the gNB or a primary TRP of the gNB of <FIG>.

In some embodiments, where apparatus <NUM> represents an IAB node, it may be configured in a DU and MT architecture that divides the IAB functionality. In certain embodiments, the apparatus <NUM> may comprise more than one DUs.

In some embodiments, apparatus <NUM> may also include or be coupled to one or more antennas <NUM> for transmitting and receiving signals and/or data to and from apparatus <NUM>. Apparatus <NUM> may further include or be coupled to a transceiver <NUM> configured to transmit and receive information. The transceiver <NUM> may include, for example, a plurality of radio interfaces that may be coupled to the antenna(s) <NUM>. The radio interfaces may correspond to a plurality of radio access technologies including one or more of GSM, NB-IoT, LTE, <NUM>, WLAN, Bluetooth, BT-LE, NFC, radio frequency identifier (RFID), ultrawideband (UWB), MulteFire, and the like. The radio interface may include components, such as filters, converters (for example, digital-to-analog converters and the like), mappers, a Fast Fourier Transform (FFT) module, and the like, to generate symbols for a transmission via one or more downlinks and to receive symbols (for example, via an uplink).

In addition, in some embodiments, transceiver <NUM> may be included in or may form a part of transceiver circuitry.

According to certain embodiments, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to perform the functions associated with any of the embodiments described herein, such as some operations of flow or signaling diagrams illustrated in <FIG>.

For instance, in one embodiment, apparatus <NUM> (e.g., a primary TRP) may be controlled by memory <NUM> and processor <NUM> to receive an indication of a capability of a user equipment (UE) to receive a multi-TRP transmission of a message <NUM> of a random access procedure. The indication may be a physical random access channel (PRACH) preamble. In an embodiment, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to transmit a random access response (RAR) in a message <NUM> of the random access procedure based on receiving the indication of the capability. In some embodiments, the RAR may be configured to allocate resources for transmission of information on at least one additional beam. In some embodiments, the RAR may comprise at least one field configured to signal a command to indicate the at least one additional beam in a message <NUM> of the random access procedure. In an embodiment, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to receive, in the message <NUM>, at least one index of the at least one additional beam after transmitting the RAR.

In another embodiment, apparatus <NUM> (e.g., a primary TRP) may be controlled by memory <NUM> and processor <NUM> to transmit a paging message (or a control message, in some embodiments). In some embodiments, the paging message may comprise information identifying: a resource indication configured to indicate at least one of a size and a frequency location of a physical uplink shared channel (PUSCH) resource for a message A of a random access procedure and for indicating at least one additional beam in the random access procedure. In an embodiment, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to receive the message A after transmitting the paging message. In some embodiments, the message A may be transmitted using the physical random access channel (PRACH) preamble followed by an indication of the at least one additional beam in the PUSCH resource.

In another embodiment, apparatus <NUM> (e.g., a primary TRP) may be controlled by memory <NUM> and processor <NUM> to transmit, by a primary transmit receive point (TRP), a paging message. In an embodiment, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to receive a physical random access channel (PRACH) preamble of a random access procedure. In some embodiments, the PRACH preamble may identify at least one selected SSB beam from the SSB beams.

<FIG> illustrates an example of an apparatus <NUM> according to another embodiment. In an embodiment, apparatus <NUM> may be a node or element in a communications network or associated with such a network, such as a UE, mobile equipment (ME), mobile station, mobile device, stationary device, IoT device, or other device. As described herein, UE may alternatively be referred to as, for example, a mobile station, mobile equipment, mobile unit, mobile device, user device, subscriber station, wireless terminal, tablet, smart phone, IoT device, sensor or NB-IoT device, or the like. As one example, apparatus <NUM> may be implemented in, for instance, a wireless handheld device, a wireless plug-in accessory, or the like.

As discussed above, according to some embodiments, apparatus <NUM> may be a UE, mobile device, mobile station, ME, IoT device and/or NB-IoT device, for example. According to certain embodiments, apparatus <NUM> may be controlled by memory <NUM> and processor <NUM> to perform the functions associated with example embodiments described herein. For example, in some embodiments, apparatus <NUM> may be configured to perform one or more of the processes depicted in any of the flow charts or signaling diagrams described herein, such as those illustrated in <FIG>.

For instance, in one embodiment, apparatus <NUM> (e.g., a UE) may be controlled by memory <NUM> and processor <NUM> to receive, from a primary transmit receive point (TRP), a paging message (or a control message, in some embodiments). In an embodiment, apparatus <NUM> (e.g., a UE) may be controlled by memory <NUM> and processor <NUM> to transmit, to the primary TRP, an indication of a capability to receive a multi-TRP transmission of a message <NUM> of a random access procedure. In some embodiments, the indication may be a physical random access channel (PRACH) preamble. In an embodiment, apparatus <NUM> (e.g., a UE) may be controlled by memory <NUM> and processor <NUM> to receive, from the primary TRP, a random access response (RAR) in a message <NUM> of the random access procedure based on transmitting the indication of the capability. In some embodiments, the RAR may be configured to allocate resources for transmission of information on at least one additional beam. In some embodiments, the RAR may comprise at least one field to signal a command to indicate the at least one additional beam in a message <NUM> of the random access procedure. In an embodiment, apparatus <NUM> (e.g., a UE) may be controlled by memory <NUM> and processor <NUM> to transmit, to the primary TRP, in the message <NUM> of the random access procedure, at least one index of the at least one additional beam after receiving the RAR.

In another embodiment, apparatus <NUM> (e.g., a UE) may be controlled by memory <NUM> and processor <NUM> to receive, from a primary transmit receive point (TRP), a paging message. In some embodiments, the paging message may comprise information identifying: a resource indication configured to indicate at least one of a size and a frequency location of a physical uplink shared channel (PUSCH) resource for a message A of a random access procedure and for indicating at least one additional beam in the random access procedure, and a delay from a physical random access channel (PRACH) occasion for the indicating. In an embodiment, apparatus <NUM> (e.g., a UE) may be controlled by memory <NUM> and processor <NUM> to transmit, to the primary TRP, the message A after receiving the paging message. In some embodiments, the message A may be transmitted using a PRACH preamble followed by an indication of the at least one additional beam in the PUSCH resource.

In another embodiment, apparatus <NUM> (e.g., a UE) may be controlled by memory <NUM> and processor <NUM> to receive, from a primary transmit receive point (TRP), a paging message. In an embodiment, apparatus <NUM> (e.g., a UE) may be controlled by memory <NUM> and processor <NUM> to determine a mapping, from the paging message or system information, of each of a set of reserved physical random access channel (PRACH) preambles to at least one of multiple SSB beams on which a user equipment (UE) determines to receive a multi-TRP transmission. In an embodiment, apparatus <NUM> (e.g., a UE) may be controlled by memory <NUM> and processor <NUM> to transmit a PRACH preamble of a random access procedure. In some embodiments, the PRACH preamble may have been selected from the set of reserved PRACH preambles based on at least one beam measurement of the SSB beams and the mapping.

Therefore, certain example embodiments provide several technological improvements, enhancements, and/or advantages over existing technological processes. For example, one benefit of some example embodiments is improved reliability and latency of Mobile Terminated (MT) EDT. Accordingly, the use of some example embodiments results in improved functioning of communications networks and their nodes and, therefore constitute an improvement at least to the technological field of wireless control and management, among others.

In some example embodiments, the functionality of any of the methods, processes, signaling diagrams, algorithms or flow charts described herein may be implemented by software and/or computer program code or portions of code stored in memory or other computer readable or tangible media, and executed by a processor.

In some example embodiments, an apparatus may be included or be associated with at least one software application, module, unit or entity configured as arithmetic operation(s), or as a program or portions of it (including an added or updated software routine), executed by at least one operation processor. Programs, also called program products or computer programs, including software routines, applets and macros, may be stored in any apparatus-readable data storage medium and may include program instructions to perform particular tasks.

A computer program product may include one or more computer-executable components which, when the program is run, are configured to carry out some example embodiments. The one or more computer-executable components may be at least one software code or portions of code. Modifications and configurations required for implementing functionality of an example embodiment may be performed as routine(s), which may be implemented as added or updated software routine(s). In one example, software routine(s) may be downloaded into the apparatus.

As an example, software or a computer program code or portions of code may be in a source code form, object code form, or in some intermediate form, and it may be stored in some sort of carrier, distribution medium, or computer readable medium, which may be any entity or device capable of carrying the program. Such carriers may include a record medium, computer memory, read-only memory, photoelectrical and/or electrical carrier signal, telecommunications signal, and/or software distribution package, for example. The computer readable medium or computer readable storage medium may be a non-transitory medium.

In other example embodiments, the functionality may be performed by hardware or circuitry included in an apparatus (e.g., apparatus <NUM> or apparatus <NUM>), for example through the use of an application specific integrated circuit (ASIC), a programmable gate array (PGA), a field programmable gate array (FPGA), or any other combination of hardware and software. In yet another example embodiment, the functionality may be implemented as a signal, such as a non-tangible means that can be carried by an electromagnetic signal downloaded from the Internet or other network.

One having ordinary skill in the art will readily understand that the example embodiments as discussed above may be practiced with steps in a different order, and/or with hardware elements in configurations which are different than those which are disclosed.

As used herein, the term "BS" may refer to a gNB, a NG-NB, an eNB, a Node B, or the like. In addition, the terms "BS," "gNB," "NG-NB," "eNB," "Node B," or the like may be used interchangeably.

Claim 1:
A method, comprising:
receiving (<NUM>), by a user equipment and from a primary transmit receive point, a message;
transmitting (<NUM>), by the user equipment and to the primary transmit receive point, an indication of a capability to receive a multi-transmit receive point transmission of a message <NUM> of a random access procedure,
wherein the indication is a physical random access channel preamble;
receiving (<NUM>), by the user equipment and from the primary transmit receive point, a random access response in a message <NUM> of the random access procedure based on transmitting the indication of the capability,
wherein the random access response is configured to allocate resources for transmission of information on at least one additional beam, and
wherein the random access response comprises at least one field to signal a command to indicate the at least one additional beam in a message <NUM> of the random access procedure; and
transmitting (<NUM>), by the user equipment and to the primary transmit receive point, in the message <NUM> of the random access procedure, at least one index of the at least one additional beam after receiving the random access response.