Systems and methods for beamformed uplink transmissions

Abstract

Disclosed herein are systems and methods for beamforming and uplink control and data transmission techniques. Such techniques enable a UE to maintain at least one beam process in order to perform operations using multiple beams and / or points. A beam process is indicated for transmission or reception on a downlink or uplink physical channel. Power, timing, and channel state information may be specific to a beam process. A beam process may be established as part of a random access procedure, where resources may be provided in a random access response message. The techniques provided are intended to handle beam process failures, use beam processes for mobility, and select beams using open-loop and closed-loop selection procedures.

Description

[0001] This application is a divisional application of Chinese Patent Application No. 201780029149.4, entitled “System and Method for Uplink Transmission with Beamforming”, filed on May 3, 2017, which is incorporated herein by reference.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application is a non-provisional application of, and claims the benefit of 35 U.S.C. §119(e) of, U.S. Provisional Patent Applications Serial No. 62 / 334,754, filed May 11, 2016, entitled “Systems and Methods for Beamformed Uplink Transmission”; Serial No. 62 / 373,076, filed August 10, 2016, entitled “Systems and Methods for Beamformed Uplink Transmission”; and Serial No. 62 / 440,903, filed December 30, 2016, entitled “Systems and Methods for Beamformed Uplink Transmission”. All of these applications are incorporated herein by reference in their entirety. Background Art

[0004] To meet the high data rates required by next generation cellular communication systems, the wireless industry and academia have been exploring methods to exploit the large bandwidth available at very high frequencies, such as centimeter wave and millimeter wave frequencies.

[0005] These high frequencies may have propagation characteristics that are not conducive to wireless communications, especially in outdoor environments. Transmissions at higher frequencies may experience higher free-space path losses. Precipitation and atmospheric gases (e.g., oxygen and vegetation) may further increase attenuation compared to frequencies below 6 GHz. In addition, penetration and diffraction attenuation may be more severe at higher frequencies (e.g., at mmWave frequencies).

[0006] All of these propagation characteristics can result in significant non-line-of-sight (NLOS) propagation path loss. For example, at mmWave frequencies, NLOS path loss can be more than 20 dB higher than line-of-sight (LOS) path loss and severely limit the coverage of mmWave transmissions. Summary of the invention

[0007] In order to improve throughput and maintain adequate coverage in higher frequency bands, new radio (NR) systems use more UE antenna elements than traditional systems. In the case of UE using up to 64 antenna elements, traditional methods for controlling multi-antenna transmissions become impractical due to the up to 64 orthogonal reference signals to be transmitted and the signaling precoders for 64 antenna ports. Example embodiments allow the UE to determine a set of precoding weights and other parameters for uplink or sidelink transmissions.

[0008] Likewise, in the downlink direction, network equipment may be equipped with more antenna elements than conventional systems, rendering current approaches impractical. The illustrated embodiments select precoding weights for reception (downlink or sidelink) and feedback so that precoding weights can be appropriately selected on the network side. The illustrated embodiments also achieve other desirable design features for NR, such as not relying on continuous transmission of a common downlink reference signal, which can result in energy inefficiency and limited spectral efficiency.

[0009] In operation, the use of narrow beam patterns may cause the received energy to suddenly degrade during the rotation and dynamic blocking of the UE. Disclosed herein is a method for adjusting the beam and managing the beam process when the channel suddenly changes due to the UE's own rotation or dynamic blocking during system processes or active data transmission / reception.

[0010] Beamforming and uplink control and data transmission techniques enable a UE to maintain at least one beam process that uses multiple beams and / or points to perform operations. A beam process can be indicated for transmission or reception on a downlink or uplink physical channel. Power, timing and channel state information can be specific to a beam process. A beam process can be established as part of a random access procedure, where resources can be provided in a random access response message. The provided techniques are intended to handle beam process failures, use beam processes for mobility, select beams using open-loop and closed-loop selection processes, implement simultaneous beam process power allocation, implement beam process maximum power backoff (MPR) (e.g., caused by SAR), implement beam reselection due to MPR, and implement beam reselection and re-pairing due to UE rotation and dynamic blocking.

[0011] Compared to conventional systems, the systems and methods disclosed herein provide support for a large number of antenna elements at the UR end used in 5G NR. The systems and methods disclosed herein further relate to effectively selecting precoding weights for UE reception and transmission. The beam-based exemplary NR systems and methods disclosed herein reduce the reliance on continuous transmission of common downlink reference signals, thereby achieving energy efficiency and spectral efficiency.

[0012] In an exemplary embodiment, in order to perform operations using one or more beams and / or points, the UE maintains a beam process for each beam and / or point. A beam process may be indicated for transmission / reception on a downlink or uplink physical channel. Power, timing, and channel state information may be specific to a beam process. A beam process may be established as part of a random access procedure, where resources may be provided in a random access response. The UE may monitor link quality specific to a beam process and may declare a link failure for a beam process based on a single or aggregated beam quality. The UE may handle mobility based on the use of a beam process. The UE may perform a beam selection process for each beam process using (i) an open loop (e.g., based on channel reciprocity) and / or (ii) a closed loop (e.g., based on beam measurements). BRIEF DESCRIPTION OF THE DRAWINGS

[0013] A more detailed understanding may be obtained from the following description given by way of example in conjunction with the accompanying drawings.

[0014] Figure 1 A three-dimensional illustration of the beam pattern is described.

[0015] Figure 2 A functional block diagram of the beamforming process is described.

[0016] Figure 3A An example beam profile is shown when the beam center direction is the same as the beam peak direction.

[0017] Figure 3B An example beam profile is shown when the beam center direction is different from the beam peak direction.

[0018] Figure 4 is a schematic diagram of an exemplary embodiment of beam propagation.

[0019] Figure 5 A beam transmission pattern is described for illustrating beam groups and beam classification.

[0020] Figure 6 is a schematic diagram illustrating one embodiment of an uplink beam reselection process with respect to an active beam process affected by SAR.

[0021] Fig. 7A An example communication system is described in which one or more disclosed embodiments may be implemented.

[0022] Figure 7B Describes the Fig. 7AAn example radio access network (RAN) and an example core network for use within a communication system of FIG.

[0023] Figure 7C Describes the Fig. 7A A second exemplary RAN and a second exemplary core network are used within the communication system.

[0024] Fig.7D Describes the Fig. 7A A third exemplary RAN and a third exemplary core network used within a communication system.

[0025] Fig. 7E Describes the Fig. 7A An example wireless transmit / receive unit (WTRU) for use within a communication system of FIG.

[0026] Figure 7F Describes the Fig. 7A An example network entity used within a communication system of FIG. DETAILED DESCRIPTION

[0027] Beam-based 5G radio access

[0028] Recent channel measurements performed by the wireless industry and academia have demonstrated the feasibility of achieving satisfactory cellular coverage with beamforming techniques. The measurement data show that beamforming gain provides coverage for cellular control signaling and increases link capacity to achieve higher data throughput under LOS conditions.

[0029] The channel propagation characteristics of 5G NR cellular systems and their high data throughput may require the use of beamforming on all physical layer signals and channels (including those used for broadcast and common purposes, as well as those focused on beam-based or beam-centric processes). 5G NR system designs can implement beamformed access links where beamforming is used on most or all physical layer signals and channels. These physical layer signals and channels can have different beamforming techniques applied (including digital, analog, and hybrid beamforming) and can store their dedicated beamforming configurations.

[0030] Compared with traditional cellular systems, beamforming can provide additional degrees of freedom in the angular domain. System design can consider beamforming processing specific to each physical layer signal and channel and beam-based characteristics, and can introduce corresponding control and system processes (such as uplink transmission, cell search, random access, and control channel decoding).

[0031] Beamforming Technology

[0032] Beamforming techniques include digital, analog, and hybrid beamforming. For digital beamforming, each antenna element can have a dedicated RF chain that includes RF processing and ADC / DAC. The signal processed by each antenna element can be independently controlled in phase and amplitude to optimize channel capacity. The number of RF chains can be equal to the number of antenna elements. While providing high performance, digital beamforming technology is also accompanied by high cost, implementation complexity, and high energy consumption.

[0033] Analog beamforming can apply one RF chain to multiple antenna elements that make up a phased antenna array (PAA). Each antenna element can use phase shifters to set pure phase weights to perform beamforming and steering of the PAA antenna pattern. The number of RF chains applied can be much less than the number of antenna elements. The number of RF chains can be equal to or less than the number of PAAs. For example, multiple PAAs can be connected to a single RF chain, and each PAA can have an antenna pattern for specific azimuth and elevation coverage. RF chains can be switched to one PAA at a time to use a single RF chain in conjunction with multiple PAAs to provide wide coverage by using one beam in different directions and at different times.

[0034] Hybrid beamforming may combine a digital precoding process with analog beamforming. Analog beamforming may be performed on the antenna elements of a PAA connected to an RF chain. A digital precoding process may be applied to the baseband signals of each RF chain and the PAA associated therewith. The configuration of hybrid beamforming may include the number of data streams, the number of RF chains, the number of PAAs, and the number of antenna elements. A PAA connected to an RF chain may be represented by an antenna port that is uniquely identified by a beamforming reference signal dedicated to that antenna port.

[0035] Figure 1 is a graph 100 of an example UE three-dimensional transmit beam pattern using a 4×4 uniform linear array.

[0036] Figure 2 An example UE block diagram is shown for a hybrid beamforming system 200 with two transmitters 202, 204 and two phase antennas 206, 208. It starts with a digital precoding process 210 in a BB processing block 212. The I (214, 218) and Q (216, 220) output signals pass through ADC blocks 222, 224 and RF processing blocks 226, 228 to be transmitted via the phase-shifted antenna arrays 206, 208 for analog beamforming.

[0037] The high implementation cost and high energy consumption of digital beamforming techniques may lead to implementation considerations for NR system design. 5G NR beamforming techniques may be based on hybrid beamforming, where the number of 5G NR transceiver nodes is much less than the number of antenna elements. Analog beamforming techniques may have a significant impact on L1 / L23 system procedures and may lead to new procedure behaviors and sequences. Beamformed transmissions can provide high flexibility to the eNB to reduce signal overhead and energy consumption by customizing transmissions in the time and spatial domains.

[0038] LTE / LTE-A uplink multi-antenna technology

[0039] LTE and LTE-A consider multiple antenna techniques. For transmit antenna selection, open-loop antenna selection masks the scrambling process on the uplink grant CRC bits. Closed-loop transmit antenna selection is configured by higher layers based on optional UE capability reports. The Spatial Orthogonal Resource Transmit Diversity (SORTD) method is the same as UCI on different UE antennas using different orthogonal resources. For PUCCH, dual antennas are used. For MU-MMO, each of up to eight UEs on the same set of RBs uses a single antenna transmission. And, the 3-bit PUSCH cyclic shift and OCC for PUSCH DMRS provide orthogonality. The MU-MMO method is transparent to the UE. For SU-MIMO, there is a precoder that is constrained by the CM (e.g., one layer per antenna). And, the eNB selects the precoder based on the non-precoded SRS, and uses DCI 4 to signal the number of layers and PMI. The SU-MIMO method uses SRS on each antenna port.

[0040] Uplink transmission control

[0041] The wireless system controls transmissions originating from a UE (e.g., uplink or sidelink) by using mechanisms to ensure proper link adaptation while preventing excessive interference to other UEs. As examples, these mechanisms include transmit power control, timing calibration, and transmission parameter indicators (e.g., modulation, coding, and frequency allocation). In LTE, a UE equipped with multiple antenna components can be instructed to apply it to the transmission through precoding weights. The mechanism can use a UE that transmits a reference signal for each antenna component to determine the precoder that maximizes the quality at the receiving end. By using such a precoder, the transmission power of a specified transmission can be reduced, and this will naturally reduce the interference caused to the system. In LTE, the maximum number of reference signals (or antenna ports) used for uplink transmission is 4.

[0042] UE autonomous rotation and blocking detection

[0043] It is not uncommon for UE to be equipped with various motion sensors, including accelerometers, gravity sensors, gyroscopes, rotation vector sensors, etc. Accelerometers and gyroscopes are hardware-based, and other software-based sensors can derive further motion data based on the inputs received from these two hardware-based sensors.

[0044] The sensor data provides the UE with detailed detection information about the rotational movement of the UE. The rotational movement can reflect direct user input, such as tilting, shaking, rotating or swinging movement of the UE during video gaming. The detected rotation data allows the UE to calculate the angular change in the orientation of its own antenna array. The orientation change can be represented by the rotation rate around the X / Y / Z axes and the corresponding vector components on each axis.

[0045] The UE's motion sensors can collect data generated by relative motion. Relative motion can reflect the physical environment in which the UE is located. For example, in some embodiments, the motion sensors can detect the approach of a stationary obstacle or the movement of a moving obstacle towards a stationary UE due to the movement of the UE. In such embodiments, the motion sensor data enables the UE to detect an impending blockage and estimate the translational motion vector of the blockage (including its speed and direction relative to the UE).

[0046] In an exemplary embodiment, the advanced motion sensor can be operated to distinguish between a human body and inert materials. Thus, in such embodiments, the UE can not only detect an approaching obstruction, but also distinguish whether the obstruction is a human body. This feature can be used by the UE to comply with the specific absorption rate (SAR) regulations for handheld devices.

[0047] Beam

[0048] The term "beam" is used in several different contexts in this specification. A beam can be used to refer to a set of precoding weights or co-phasing weights applied to an antenna element in a user equipment (UE) or network device (e.g., a transmission or reception point) to perform transmission or reception. The term beam can also refer to an antenna or radiation pattern resulting from the application of such precoding weights, or to at least one reference signal transmitted when the set of precoding weights is applied to an antenna element; at least one sequence used to generate the at least one reference signal. Other references include a set of properties associated with the antenna pattern, such as gain, directivity, beamwidth, beam direction measured in azimuth and elevation (relative to a reference plane), peak to sidelobe ratio, or at least one antenna port associated with such an antenna pattern. In addition, the term beam can also refer to the relevant number and / or configuration of antenna elements (e.g., a uniform linear array, a uniform rectangular array, or other uniform array).

[0049] Beam Process

[0050] Beam classes refer to beams that have at least one characteristic in common, such as beam width or beam solid angle. A higher beam class refers to a higher directional order, while a lower beam class refers to a lower directional order. A beam family consists of all beams with the same beam class. A beam group is a group of beams associated with beams with a lower beam class. A beam can be associated with a beam with a lower beam class, for example based on the beam with the closest center direction or the beam with the greatest overlap or correlation.

[0051] Figure 3A and 3B are two graphs 300, 350 comparing beam amplitude to direction 308, 316 showing the difference between beam center directions 304, 314 and beam peak directions 306, 312. A beam direction is a beam direction that can be defined as a beam center direction 304, 314 or as a beam peak direction 306, 312. Figure 3A and 3B EIRP peaks 302, 310 are also indicated by black dots. A beam space is the area or solid angle covered by a set of beams, which may have an arbitrary weight vector. A beam space may be bounded or defined by a set of parameters, such as a set of angles or the beams themselves.

[0052] In some exemplary embodiments, the UE may set precoding weights and other parameters for transmitting and / or receiving signals, control, and data in accordance with at least one beam process. The UE may calculate or modify the values ​​of such parameters and may use these values ​​in subsequent transmission or reception processes that reference the beam process (e.g., by using a beam process identifier). Such exemplary processes significantly reduce the overhead associated with determining precoding weights by not relying on continuous transmission of reference signals and not involving signaling the precoding process for each transmission. Such exemplary processes also reduce the implementation complexity of advanced transmission schemes (e.g., spatial multiplexing, beam diversity, or coordinated multi-point) by using more than one beam process. A beam process may be referred to as a beam paired link (BPL).

[0053] For transmission from the UE, the beam process can determine at least one set of precoding or common phase weights to be applied to the antenna elements. This determination can form beams, where each such set can correspond to an antenna port. The transmission beam process can determine the timing advance or transmission power level relative to the downlink timing reference signal. For reception from the UE, the beam process can determine at least one set of precoding weights to be applied to the antenna elements for reception. Similarly, this determination process can form beams, where each such set can correspond to an antenna port. The beam process can also determine the setting of the automatic gain controller (AGC).

[0054] In some exemplary embodiments, a bidirectional beam process may control both transmission and reception, and may determine different precoding weights or beam sets for transmission and reception. Alternatively, a beam process may control only transmission (transmit, or UL beam process) or only reception (receive, or DL ​​beam process).

[0055] The UE may determine that the beams used in the receive and transmit beam processes, respectively, or in the receive and transmit beam processes, in the bidirectional beam process, should have the same pattern or a similar pattern. This determination may be based on higher layer signaling, or this determination may be implicitly based on the frequency band or other properties of the system to which the UE is accessing or to which the UE is connected. In this case, the UE may derive the precoding weights used in transmission based on the precoding weights determined for reception, and vice versa. For the transmit and receive beam processes, such processing may then be referred to as being associated by reciprocity. For the bidirectional beam process, the processing may be referred to as mutual.

[0056] In some embodiments, a default beam process may be defined. Such a default beam process may be applied to downlink or uplink transmissions without specific configuration, or may be determined from higher layer signaling. Such a default beam process may be predefined such that the maximum beam gain or directivity produced is minimized, or such that the pattern is approximately omnidirectional.

[0057] The use of the default beam process may also depend on the frequency band (e.g., according to a predetermined rule or higher layer signaling). For example, whether a PRACH transmission should use the default beam process may be indicated as part of the RACH configuration, which may be provided via system information. Such signaling may be particularly beneficial if the network performs system timing and path loss estimation using synchronized transmissions from multiple TRPs for transmitting signals for use by the UE.

[0058] The UE may maintain one beam for each beam process. Such beams may be selected initially and may be updated as part of the beam selection process. The beam selection process determines the beam that produces the best propagation channel (e.g., by maximizing received signal power for a specified transmit power) for a specified beam or antenna applied to another UE (e.g., a network node).

[0059] Figure 4 An example embodiment of beam propagation in system 400 is shown. At any one time, UE 402 may be configured with multiple beam processes to support spatial diversity or multiplexing, multipoint operation, and mobility. Figure 4 This is illustrated in Figure 4, where processes 1 and 2 correspond to the direct path 404 and reflected path 406 to TRP1 (410), and process 3 corresponds to path 408 to TRP2 (414). The reflected path 406 is reflected from a building 412, while the direct paths 404, 408 are line of sight. Each configured beam process can be viewed as corresponding to a transmission or reception instance with a particular antenna pattern that maximizes the beamforming gain along the channel path. Multiple beam processes can also be used to support different levels of beamforming, depending on the type of information being transmitted and the associated reliability requirements, or depending on whether the transmission is unicast or multicast.

[0060] The current beam refers to the most recent result of the beam selection process. For a bidirectional process, the current beam may be applied to both transmission and reception. Alternatively, separate current beams may be applied for transmission and reception. Similarly, the beam selection process may select a separate beam for each antenna port, thereby generating a current beam for each antenna port.

[0061] In some exemplary embodiments, when a beam process is applied to transmission or reception, the applied beam corresponds to the current beam. In some exemplary embodiments, UE 402 may maintain the beam selected in the previous beam selection process. For example, UE 402 maintains the last selected beam with the beam classification only if the beam classification (or beam gain) is lower than the beam classification (or beam gain) of the current beam. When multiple beams are maintained for a beam process, each beam may be associated with a beam identifier, which may correspond to a beam classification.

[0062] Some beam selection processes may be based on performing a series of measurements obtained from downlink reference signals. Such reference signals are referred to herein as beam selection reference signals. In some embodiments, UE 402 may adjust the settings of the AGC based on such beam selection reference signals. A beam process may be provided with resources for at least one such beam selection reference signal. The resources used to provide the beam process reference signal may include at least one identification parameter for generating a sequence and a time and frequency resource indication. For some exemplary embodiments, the identification parameter may be unique to the beam process.

[0063] Some example beam selection processes may be based on performing at least one transmission of an uplink (or sounding) reference signal, which is referred to as a beam sounding reference signal. A beam process may be provided with resources for at least one such beam sounding reference signal. The resources used to provide the beam sounding reference signal may include at least one identification parameter for generating a sequence and a time and frequency resource indication. For some example embodiments, the identification parameter may be unique to the beam process. Furthermore, the identification parameter used for the uplink may be the same as the identification parameter used to generate the beam selection reference signal.

[0064] In some example embodiments, resources for beam selection reference signals and beam sounding reference signals may be dynamically allocated. In addition, these reference signals may be allocated on a subset of available time and frequency resources. By performing such allocations, continuous broadcast of signals may be avoided and high overhead costs may be reduced. For example, downlink control information (e.g., a random access response or signaling that triggers the beam selection process) or a combination of downlink control information and higher layer signaling may indicate resource allocation.

[0065] The beam selection reference signal may be associated with a set of parameters for performing spreading or scrambling. As an example, the parameters may include a spreading factor, a spreading sequence (eg, OVSF and Walsh code) index, and a scrambling sequence index.

[0066] As described below, different resources may be associated with beam processes for data transmission / reception.

[0067] A beam process for data transmission / reception may be associated with time domain resources, which may include, for example, a time unit, a symbol block, a subframe, a time slot, and a frame. A beam process may also be associated with a set of frequency domain resources, which may include, for example, a subcarrier, a subcarrier block, a resource block, a resource block set, and a wideband carrier. A beam process may be associated with code domain resources, which may include, for example, a spreading and / or scrambling code type (OVSF / Walsh / ZC code), a spreading / scrambling length, and a spreading / scrambling sequence index.

[0068] The time / frequency / code resources associated with a beam process can be static and can be pre-configured for certain types of beam processes. For example, in some embodiments, the resources associated with a beam process used by a cell-specific common control channel can be fixed and can be broadcast in a system information broadcast transmission. In other embodiments, such beam processes can have fixed and pre-defined resource allocations. Beam processes used for data transmission and reception can also be dynamically associated with resources using downlink control information in physical layer control signaling. In another embodiment, the resource association information for each beam process can be carried in higher layer signaling (e.g., RRC signaling).

[0069] By associating beam processes with resource allocations, flexible configuration is enabled and the signaling overhead of beam processes connected to multiple TRPs or used for layered control channels for downlink / uplink / sidelink can be reduced.

[0070] UE 402 may be configured to maintain more than one beam process (eg, bidirectional or unidirectional process) (see Figure 4 ). Each such beam process can correspond to the reception or transmission of a specific antenna pattern so that the patterns of different beam processes maximize the antenna gain in different directions. Thus, for each beam process, UE 402 can maintain precoding weights, Tx power, and timing. Each beam process can be associated with a different network transmission point (e.g., TRP). Connections to multiple TRPs can support multi-point operation, diversity, seamless mobility, and fallback operation. By maintaining more than one such beam process, transmission and / or reception to and / or from multiple points or to a single point using different beams can be facilitated.

[0071] A beam process may be configured with a beam process identifier for reference purposes. A particular beam process may be designated as a master beam process or a primary beam process. If UE 402 maintains only one beam process, then the beam process may be designated as a master (or primary) beam process. If UE 402 maintains more than one beam process, then UE 402 may receive signaling for designating a master beam process.

[0072] Control channel monitoring

[0073] In some exemplary embodiments, UE 402 may determine at least one beam process for decoding a downlink control channel (e.g., a physical downlink control channel or a physical broadcast channel). When attempting to decode the downlink control channel, UE 402 may perform reception using precoding weights determined by the beam process.

[0074] In one embodiment, the beam process is associated with at least one control channel configuration that can be used by the UE 402 to determine which resources to attempt to decode downlink control information. The configuration may include at least one of the following:

[0075] - At least one control resource set, control subband or control time symbol within a scheduling unit (eg, a time slot, a mini-time slot or a subframe).

[0076] - at least one parameter for deriving at least one search space (or candidate set) for a control channel instance within at least one control resource set.

[0077] οThe at least one search space may be defined at least according to a control channel set, a resource element group, a time symbol set and / or a physical resource block subset within a control resource set.

[0078] οAt least one beam process can be associated with a common search space.

[0079] - At least one parameter for determining a subset of possible scheduling units (e.g., time slots) in which downlink control information transmitted using a beam process may exist (e.g., a period and an offset in units of time slots (or mini-time slots)). In some embodiments, more than one such subset may be configured, which may be selected based on an activity state or priority associated with a beam process.

[0080] - at least one parameter for determining at least one property (eg sequence) of a reference signal used at least for the purpose of decoding a control channel.

[0081] The configuration may be obtained from RRC signaling (eg, dedicated signaling from at least a physical broadcast channel and / or system information).

[0082] Standalone configuration and example usage scenarios

[0083] Each beam process can be configured with or associated with an independent control channel configuration to allow for maximum flexibility. For example, control subbands or resource sets can be configured differently between different beam processes, which can be useful in scenarios associated with geographically separated TRPs that use different resources for control signaling to achieve better interference coordination.

[0084] In another example, the time symbols within the time slot can be configured in different ways, which can be useful in scenarios where uplink and downlink data transmission involve different TRPs (e.g., heterogeneous network scenarios with low and high transmission power TRPs). In such a scenario, downlink assignments can be received from a first TRP by using a first beam process, and uplink assignments can be received from a second TRP by using a second beam process.

[0085] In some embodiments, in order to reduce signaling overhead, at least one parameter of the control channel configuration may be common to all beam processes.

[0086] Priority between beam processes

[0087] In some cases, there may be overlap between resources used by different beam processes, and therefore, reception using at least one such beam process is not feasible. For example, this may occur if the UE 402 can only use a maximum of N beam processes at a given time (where N may correspond to the number of RF chains, as an example, in an embodiment of the UE receiver), and there is overlap in the time domain between the control channel candidates of more than N beam processes in a given time slot. In another example, a control channel candidate for a first beam process may overlap with a transmission scheduled for a second beam process. When this occurs, the UE 402 may apply a priority rule between the beam processes based on at least one of the following criteria.

[0088] -Configured priority associated with each beam process. For example, UE 402 may prioritize control channel reception for the primary beam process or based on an index associated with a beam process (eg, a lower index has a higher priority).

[0089] - An activity state associated with each beam process. For example, a beam process in an "active" state may be prioritized over a beam process in an "inactive" state; alternatively, a beam process in an "inactive" state may be prioritized to provide a fallback mechanism in the event that the quality of an active beam process degrades.

[0090] - The periodicity of the scheduling unit subset when monitoring its control channel for a beam process. For example, priority may be given to the beam process with the largest periodicity.

[0091] - The last reported channel state indication for each beam process. For example, priority may be given to the beam process with the highest channel quality indication.

[0092] - The type of transmission associated with the beam process. For example, a transmission scheduled for the first beam process may take precedence over a control channel candidate for the second beam process. In another example, such a scheduled transmission may be scheduled in a previous time slot and overlap with the control resource set of the current time slot.

[0093] If a rule does not allow for differentiation, then multiple rules can be used to handle the instance. For example, UE 402 can first perform prioritization based on activity status, and if more than one process has the same activity status, then a rule based on configured priority can be used. Alternatively, other rule conditional sorting can also be used.

[0094] Relationship with antenna ports

[0095] For some exemplary embodiments, a fixed or semi-static association may be established between a beam process and an antenna port or a set of antenna ports. Whenever configured to transmit or receive through an antenna port, UE 402 applies the precoding weights of the corresponding beam process. The set of antenna ports associated with a beam process may be quasi-co-located with each other in space. For example, if an association is defined between an antenna port used to transmit a demodulation reference and an antenna port used to transmit a reference signal (e.g., CSI-RS or beam selection RS) for beam selection for a beam process, then the association may indicate that such antenna ports are quasi-co-located in space. Therefore, using an antenna port to implicitly or explicitly indicate a beam for reception is equivalent to indicating that the antenna port is quasi-co-located in space with a reference signal (e.g., CSI-RS) of a beam process or beam pairing link. Alternatively, for some exemplary embodiments, the association between a beam process and an antenna port may be dynamically modified. UE 402 may determine an applicable beam process for transmission or reception through an antenna port.

[0096] In one exemplary embodiment, the applicable beam process may be determined from an explicit indication received from a physical layer or higher layer signaling. For example, UE 402 may receive downlink control information (DCI) indicating an uplink (or sidelink) transmission (grant) on an uplink (or sidelink) physical channel, and such grant may include an indication of an applicable beam process for transmission on each antenna port. Such beam process may be different from the beam process used to receive the DCI. In another exemplary embodiment, UE 402 may receive downlink control information indicating a received downlink assignment from a downlink physical channel, and such assignment may include an indication of an applicable beam process for reception on each antenna port. In another exemplary embodiment, UE 402 may receive a MAC control element or RRC message indicating an applicable beam process for transmission or reception on each antenna port for subsequent transmission or reception over an uplink, sidelink, or downlink physical channel.

[0097] In another exemplary embodiment, the applicable beam process may be implicitly determined based on the beam process used to decode the associated transmission. For example, the applicable beam process for a downlink transmission may correspond to the beam process used to decode the DCI indicating the downlink transmission from the downlink physical channel. In some cases, the downlink transmission may be a downlink physical data channel, a second downlink physical control channel, or a downlink signal (e.g., a DM-RS or CSI-RS). In another example, the applicable beam process for an uplink transmission (e.g., an uplink physical channel or signal) may correspond to the beam process used to decode the DCI indicating or triggering the uplink transmission. In particular, an applicable beam process for an uplink control channel containing HARQ-ACK feedback associated with a downlink data transmission may correspond to a beam process used to decode a DCI indicating the downlink data transmission; and / or an applicable beam process for an uplink control (or data) channel containing a CSI report may correspond to a beam process used to decode a DCI indicating a transmission of a reference signal (one or more reference signals, such as a CSI-RS) used to derive the report. In another example, for an uplink control channel containing HARQ-ACK for a downlink transmission, the applicable beam process for the channel may correspond to a beam process used to decode the downlink transmission. In another example, an applicable beam process for a random access response may correspond to a beam process used to transmit a random access preamble.

[0098] In the above examples, the correspondence between the beam processes is that all two processes are the same (eg, for bidirectional beam processes) or all two beam processes are related by reciprocity.

[0099] Alternatively, in some embodiments, the correspondence may be configured via physical or higher layer signaling. For example, for UL data transmission, when a beam process is used to decode the DCI indicating the transmission, the applicable beam process for the transmission may be configured via RRC signaling. Such embodiments may allow transmissions and receptions originating from different network TRPs, which may be particularly advantageous in heterogeneous deployments where the best node for downlink transmission may be a high-power TRP and the best node for uplink transmission may be (closer to) a low-power TRP. In another example, the applicable beam process for random access responses may be configured to correspond to a default beam process (e.g., an omnidirectional beam) and thereby be configured as part of the RACH configuration. This configuration may allow synchronous transmission of random access responses from multiple TRPs.

[0100] In another example, the correspondence may be obtained in a more dynamic manner, such as through MAC signaling or physical layer signaling. Such embodiments may allow the use of different beam processes (e.g., with beams located in different directions) to perform control or data reception on the one hand and data transmission on the other hand. It would be very beneficial if the maximum transmission power configured for a particular beam process is lower than the maximum transmission power configured for another beam process, so that the best beam process for downlink reception is not the beam that takes into account the best performance for uplink transmission. As an example, such a situation may occur because the impact of SAR requirements on some beam processes exceeds that on other beam processes. In this case, as an example, the UE 402 may notify the network of the configured different maximum transmission powers by transmitting one or more power headroom reports triggered by a power management maximum power reduction (P-MPR) for at least one beam process.

[0101] In another embodiment, the applicable beam process may be implicitly determined based on the time and / or frequency resources occupied by the transmission. The correspondence between resources and beam processes may be provided by higher layer signaling.

[0102] In another exemplary embodiment, the applicable beamforming process may be determined based on the physical channel or signal type over which the transmission or reception occurs.

[0103] In another exemplary embodiment, the applicable beam process may be determined based on the type and / or content of the transmission, such as whether the transmission includes control information (e.g., uplink or sidelink) or higher layer data, or whether the transmission is multicast or unicast (e.g., for sidelink transmission). As an example, a scheduling request transmission may be performed using a specific beam process (e.g., a main beam process).

[0104] When multiple beams are maintained for a beam process, embodiments similar to those described above may be used to determine which beam identification should be used for a particular transmission. For some embodiments, the sequence used to generate the demodulation reference signal may be beam process specific. Such a sequence may be generated using identification parameters that match identification parameters used to generate a sequence for a beam selection or beam sounding reference signal.

[0105] Beam correspondence determination

[0106] In some embodiments, UE 402 may determine a correspondence between a beam for transmission (a transmit beam or uplink beam) and a beam for reception (a receive beam or downlink beam) for at least one pair of transmit beams and receive beams. If such a correspondence is determined, UE 402 may determine that a transmit beam for a first transmission from UE 402 is a transmit beam corresponding to a receive beam for receiving a second transmission. Such a receive beam may correspond to a receive beam that is used to maximize signal strength or quality when receiving the second transmission. The following paragraphs describe such embodiments.

[0107] Predetermined or static beam mapping

[0108] In one embodiment, beam correspondence may be predetermined for at least a subset of all transmit and receive beams according to a mapping stored in a memory. The mapping may be performed as part of a calibration or testing process. The mapping may minimize the difference in radiation pattern (or characteristics thereof, such as the direction that maximizes gain) between a transmit beam and its corresponding receive beam. The mapping may also cause precoding weights for the transmit and receive beams to have the same or approximately the same value.

[0109] Dynamic beam mapping status

[0110] In some embodiments, beam correspondence between the transmit beam and the receive beam may not always exist due to implementation conditions (e.g., differences in TX and RX RF paths) and / or operating conditions (e.g., temperature changes, reference clock phase drift), and thus, the determination of beam correspondence is dynamic.

[0111] The dynamic beam correspondence state can be represented by state-in and state-out. The beam correspondence state can be specific to a single beam, beam type, beam classification, beam group or antenna panel, or specific to a group of beams, beam type, beam classification, beam group or antenna panel. UE 402 can be configured to have a beam correspondence update period, and can periodically evaluate and update the beam correspondence according to the update configuration. UE 402 can perform beam correspondence state update in response to receiving L1 control or higher layer (MAC, RRC) signaling from the network. In another embodiment, once a predefined event occurs, UE 402 can trigger a beam correspondence update, which includes one or more of the following processes:

[0112] -Reconfigure new beams, beam types, beam classes, beam groups or antenna panels;

[0113] - during or at the end of a RACH procedure (e.g. by introducing an update procedure step in the Msg1 and / or Msg3 transmission; or

[0114] -Configure UL beam management procedures. The network may decide whether UL beam management may be configured according to the beam correspondence state. If the beam correspondence state is in state, the network may not configure any such procedures (e.g., U1, U2, or U3).

[0115] In one embodiment, UE 402 may update the beam correspondence status by evaluating the transmit beam and the corresponding receive beam radiation pattern and comparing / correlating pattern parameters (e.g., peak lobe direction, 3dB main lobe width, side lobe direction, side lobe width, side lobe suppression ratio, etc.) The comparison and evaluation criteria may be predefined.

[0116] In another embodiment, UE 402 may use a beam correspondence update procedure to update beam correspondence. In one embodiment, UE 402 may perform the following actions:

[0117] - Transmitting beam-specific reference signals, such as SRS, based on a set of uplink transmit beams and by using an uplink beam scanning process;

[0118] - monitoring the receive beam for downlink control information corresponding to an uplink transmit beam, wherein the downlink control information may include a best uplink transmit beam identifier, such as a beam index or an SRS resource indication (SRI);

[0119] - receiving downlink control information in one receive beam or multiple receive beams (e.g. when UE 402 is located in the middle of two downlink beams), and verifying whether the best receive beam can correspond to the uplink transmit beam identification received in the downlink control information;

[0120] - if the verification result is a match, determining that the beam correspondence is in-state, and if the verification result is a mismatch, determining that the beam correspondence is out-of-state; and

[0121] -Use uplink control signaling to report beam correspondence status.

[0122] In another embodiment, UE 402 may perform the following actions:

[0123] - performing transmission using a beam-specific reference signal in a first transmission, e.g. by means of an SRS in an uplink beam corresponding to the best downlink beam (e.g. based on an SS block), wherein the SRS resource / sequence may carry an indication of the best SS block;

[0124] - transmitting a second transmission based on an uplink transmit beam set having a beam-specific signal (e.g., SRS) including the beam-specific signal used in the first transmission and by using an uplink beam scanning process; and

[0125] - Receiving an in-state or out-of-state indication about beam correspondence in the downlink L1 control signaling delivered by the network.

[0126] For this embodiment, the network may determine the beam correspondence status by verifying whether the first SRS is the same as the best SRS received in the second transmission.It should be noted that the network may use the receive beam corresponding to the best SS block indicated in the first and second UE transmissions.

[0127] UE 402 may be configured to perform UL beam management procedures (U1 / U2 / U3) when the UE beam correspondence state is out of state. For this embodiment, UE 402 may be configured to have an explicit association between uplink and downlink beams.

[0128] When the UE beam correspondence state is in the state, the UE 402 may receive an indication in L1 control signaling or a higher layer dedicated signal to select an uplink beam based on the downlink beam without the UL beam management process. For this embodiment, the UE 402 may maintain an implicit uplink and downlink beam association.

[0129] In another embodiment, UE 402 may determine beam correspondence based on an indication from the network. For example, if beam correspondence already exists on the network side, such an embodiment will be applicable. UE 402 may first transmit a beam-specific reference signal (e.g., SRS) sequence for at least one beam (e.g., beam scanning). The transmission may be triggered by physical layer or higher layer signaling from the network. Subsequently, UE 402 may receive an indication of the transmit beam (e.g., by using an SRS indicator) and a CSI-RS indication (or CSI-RS indicator) corresponding to a certain downlink transmit beam. Such indications may be included in the same instance of physical layer signaling (downlink control information), MAC signaling (MAC control element), or RRC message. These indications may be combined with an indication that CSI-RS will be transmitted at a certain time. If the indicated CSI-RS is received, UE 402 may determine the receive beam that maximizes the signal quality. UE 402 may determine that there is a beam correspondence between the receive beam and the transmit beam used to transmit the SRS indicated by the network.

[0130] Power Control - Open Loop Component

[0131] In some example embodiments, the transmission power may depend on the beamforming process applicable to the transmission.

[0132] The transmission power may depend on a path loss measurement made on a downlink reference signal. Such a downlink reference signal may be referred to as a beam path loss reference signal. Each beam process may be independently allocated resources for such a beam path loss reference signal. In some exemplary embodiments, the beam path loss reference signal may be matched with a beam selection reference signal. The path loss measurement PL may be defined as a reference transmission power P when the current beam is applied. ref and the received signal power P r The difference between (expressed in dB).

[0133] The beam used for measurement may be a receive beam for at least a mutual bidirectional beam process, or may correspond to a receive beam process associated with a transmit beam process by reciprocity. Alternatively, the beam used for measurement may be a predefined beam, such as an omnidirectional beam or a default beam. Alternatively, the UE may select a receive beam or beam process that minimizes the estimated path loss or maximizes the received signal.

[0134] Alternatively, the receive beam used for path loss measurement can be determined based on signaling. For example, the receive beam can be signaled from system information or whether the UE 402 should use a default beam process or a selected beam process. As an example, such an embodiment can be used to determine the path loss estimate and transmission power of a PRACH transmission.

[0135] For some example embodiments, the path loss measurement may be based on the gain or directivity G of the beam used to perform the measurement. b If expressed in terms of an equation, the path loss measurement PL can be calculated as follows:

[0136] PL=P ref -P r +G b

[0137] Where P ref and P r It can be expressed in dBm, while PL and G b This adjustment can allow proper compensation for any differences in gain (or directivity) between the beam used to perform the path loss measurement and the beam used in subsequent transmissions. For the latter case, with a gain of G b The transmission power of the beam can be set to (PL-G b ') function, where PL and G b ' in dB. In some embodiments, the path loss measurement PL is not adjusted and may be equal to (P ref -P r ), but the transmission power can be set to PL+G b –G r function.

[0138] Power Control - Closed Loop Components

[0139] UE 402 may receive signaling (transmit power control (TPC) commands) for adjusting the power applied to certain transmissions. The adjustment may be cumulative on a per-beam process basis (applied to all subsequent transmissions to which a particular beam process applies). A beam process may be identified either explicitly with the TPC command or implicitly based on the beam process corresponding to the transmission to which the TPC command applies. The adjustment step value may also be independently configured for each beam process.

[0140] Power Control - Configured Maximum Power (P cmax )

[0141] In some embodiments, the UE 402 may apply a configured maximum power (eg, P-MPR) for each beam process based at least on a maximum power reduction parameter (eg, MPR, A-MPR, or P-MPR). cmax ), where P cmaxand the maximum power reduction parameter may be different. As an example, this situation may be attributed to the beam-specific power management MPR (P-MPR) value from the specific absorption radiation rate (SAR).

[0142] Configured maximum gain or configured maximum EIRP

[0143] In some embodiments, UE 402 may be operated to limit beam gain relative to a maximum possible gain, taking into account antenna configuration. As an example, this may occur when UE 402 is operated to meet a specific absorbed radiation rate requirement.

[0144] As an example, the configuration parameters may include EIRP, maximum gain (G max ) and maximum directivity. These parameters may be based on capability reports of UE 402 related to UE antenna array beamforming configuration and capabilities. The eNB may configure the parameters using higher layer signaling. In another solution, UE 402 may autonomously set the maximum gain or directivity.

[0145] UE 402 may be operated on a beam-by-beam basis and by using P cmax and maximum gain parameters to maximize EIRP. max The parameters may be affected by the physical channel associated with the beam process. For example, a beam process used for uplink control information (UCI) transmission in the physical layer uplink control channel may be assigned a lower G max Accordingly, the UE can transmit UCI in a beam process with a wide beam width. This has the advantage of improving the reliability and robustness of UCI transmission.

[0146] The UE reports the deviation between the actual applied beamforming gain and the configured maximum gain according to the beam process. This difference may be caused by MPR (e.g. caused by SRA). The eNB can receive G max The offset may trigger an uplink beam reselection process for the associated beam process. Such embodiments may allow the eNB to flexibly adjust the uplink reception process based on the beam width and beamforming gain used for the beam process.

[0147] Power allocation for simultaneous beam processes connected to different TRPs

[0148] UE 402 may add beam processes to associate with and transmit to different TRPs in mobility events. The association may include uplink beam power control information dedicated to the new TRP. UE 402 may receive power control configuration parameters for the new TRP, including uplink SINR target and TRP reference signal power. UE 402 may also receive new TRP configurations for waveforms and numerology, and may derive the required initial power and power step size accordingly.

[0149] The UE may provide the new TRP with power headroom information calculated for the associated beam process. The calculation may take into account transmissions related to all simultaneous transmissions of all active beam processes maintained by the UE 402. Thus, the power headroom may include fields for beam process identification and its corresponding power headroom value.

[0150] In an embodiment of synchronous TRP, code multiplexing can be performed on these transmissions on the same frequency resources.

[0151] In another embodiment, if the TRPs are not synchronized or deployed inter-frequency or inter-band, the UE 402 can be configured to have gaps on one TRP link to facilitate and maximize power transmission capabilities. This can be useful during mobility events in non-synchronized TRPs (e.g., FDD scenarios).

[0152] For example, the gaps may be configured by the network based on the quality of one or more current links when a UE signaling event occurs. These gap patterns may be of varying lengths and may have a finite duration, the purpose of which is to allow the UE 402 to report measurements, and the network may then determine which TRP to use and may send a configuration message, either an indication that the UE may begin monitoring certain control channels for scheduling purposes at certain TRPs, or an indication of a UE transmission start point with appropriate parameters.

[0153] If the UE 402 has more than one transceiver chain capability, the UE 402 may not rely on the configured gaps. In this particular case, synchronous or asynchronous reception / transmission will be available, and the network signaling will be reduced to the target TRP measurement indication, and one or more target TRPs will be indicated after receiving the measurement report from the UE 402. The target TRP measurement configuration can be a trigger message based on the threshold that triggers the UE 402 to issue a report. In this case, these UL transmissions will be based on carrier aggregation or dual connectivity P cmaxThe output power is shared in a similar manner as defined above. However, if deployment-specific situations occur where power sharing does not lead to good results, the network may configure gaps on the serving TRP to allow simultaneous connections with the target TRP. In this case, the gap decision may be based on measurements reported from the UE 402, where the path loss estimate may show possible scaling about the target TRP UL while maintaining the serving TRP.

[0154] Transmission timing of beam processes

[0155] In some exemplary embodiments, the transmission timing may depend on the applicable beam process. UE 402 may determine the transmission timing based on the timing of the downlink receive signal (which may be referred to as a beam timing reference signal). Each beam process may be independently provided with resources for the beam timing reference signal. In some exemplary embodiments, the beam timing reference signal and the beam selection reference signal may be the same.

[0156] The UE 402 may determine the transmission timing from the timing of the beam timing reference signal based on the applied timing advance or adjustment. Such timing advance or adjustment may be received from physical layer, MAC or RRC signaling (e.g., timing adjustment command). The timing adjustment may be specific to a beam process and may apply to all subsequent transmissions to which the particular beam process applies. A beam process may be identified either explicitly with the timing adjustment command or implicitly based on the beam process corresponding to the transmission to which the timing adjustment command applies.

[0157] In some exemplary embodiments, each beam process may be configured with a time alignment timer having a value that may be specific to the beam process. The time alignment timer for a beam process may be restarted each time a timing adjustment command is received for the beam process. The UE 402 is allowed to perform transmissions in accordance with the beam process only when the time alignment timer for the beam process is running (not expired).

[0158] Quasi-colocalization hypothesis

[0159] In some example embodiments, a UE 402 receiving a downlink physical channel using a beam process may assume that an antenna port used to transmit a reference signal associated with the beam process is quasi-co-located with one or more antenna ports used to transmit the downlink physical channel for at least one long-term channel property (e.g., timing, delay spread, or Doppler spread). Such a reference signal may correspond to a beam selection reference signal associated with the beam process.

[0160] Channel state information for each beam process

[0161] In some exemplary embodiments, UE 402 may report channel state information on a beam process by beam process basis. UE 402 may perform measurements on at least one channel state information reference signal (CSI-RS) and at least one interference measurement (EVI) resource. Resources for such signals may be provided independently for each beam process. Measurements may be performed with the current beam of a particular beam process. Physical layer signaling (e.g., a downlink control information instance) may identify the beam process and may identify the current beam. Such downlink control information may include any of the following information: a request to perform a CSI measurement, a request to report the measured CSI, a resource allocation for a CSI-RS, or an allocation for interference measurement resources.

[0162] Synchronization status of the beam process

[0163] In some example embodiments, a synchronization state may be associated with a beam process. UE 402 may determine that a beam process is in "sync" state if a synchronization timer is running and / or the last beam selection process has been successfully completed. The synchronization timer may be restarted upon successful completion of a beam selection process that resulted in at least one current beam. The duration of the timer may be either predefined, configurable by higher layers, or on a process-by-process basis. If UE 402 detects that a beam selection process was initiated and failed, the UE may stop the synchronization timer.

[0164] If the UE 402 measures a signal above a certain level or quality for at least one beam, or if the UE 402 receives an indication from the network that a beam sounding reference signal was successfully received, then the UE 402 may determine that the beam selection process is successful. The UE 402 is only allowed to perform transmission using a beam process if the beam process is in the "synchronization" state or if the applicable synchronization timer is running.

[0165] Beam Processing

[0166] Beam creation process

[0167] The process described in the following paragraphs may be used to create an initial (or primary) beam process, and / or to synchronize an initial beam process, create additional beam processes, or delete a beam process.

[0168] UE 402 may initially have no beam process or a default beam process that is not in synchronization. As an example, this may occur prior to initial access to the system or after determining that no beam process is in synchronization. Creation of an initial beam process (or synchronization of a default beam process) may be performed as part of initial system access.

[0169] In one exemplary embodiment, UE 402 may initiate a random access procedure based on measurements made on a signature sequence and / or a mobility reference signal and based on a random access configuration that may be broadcast. UE 402 may randomly select a signal, such as a preamble from a preamble group. In some exemplary embodiments, the preamble group may depend on the beamforming capabilities of UE 402. Such transmission of preambles may use a default beam, such as a very wide beam or a beam that is close to omnidirectional. Alternatively, if UE 402 can determine a beam to measure available signals, then the preamble transmission may use that beam.

[0170] UE 402 may attempt to receive at least one random access response, and if such reception does not occur within the time window, then UE 402 may retransmit the preamble at a higher power level. UE 402 may eventually decode at least one random access response, and may select one such response. Each such response may include at least a configuration and resources applicable to the beam process. Such a response includes at least one of the following: resources for beam selection reference signals; resources for beam sounding reference signals; timing advance adjustment; beam process identification; and at least one parameter for power control (e.g., reference transmission power). If a parameter for power control is not provided, then the parameter may use a value broadcast as part of the random access configuration.

[0171] The random access response may include other information elements for initial transmission on the uplink physical channel. The resources used for the beam selection reference signal may occupy a number of symbols that appear after a certain time offset after the random access response. Such a random access response may be either predefined or signaled in the random access response. The UE may determine the best beam (or current beam) for reception by measuring such resources. If the UE receives more than one random access response, the UE 402 may perform measurements on more than one corresponding beam measurement sounding reference signal resources, and may select a random access response among all responses to be followed by subsequent transmissions based at least on the measured signal quality or level.

[0172] UE 402 may use the current beam (beam selection reference signal used for the selected random access response) for transmission on beam sounding reference signal resources. Such resources may typically occupy several symbols that occur after a certain time offset after the last symbol used for the beam selection reference signal resources. Transmissions on beam sounding reference signal resources allow the network to determine the best beam at a transmission / reception point (TRP). In some exemplary embodiments, if UE 402 receives an indication from the network indicating successful reception after transmitting the beam sounding reference signal, UE 402 may continue the process. Subsequent transmissions and receptions on uplink physical channels and downlink physical channels may use the current beam determined from the beam selection reference signal measurements. Subsequently, the network may initiate further refinement of the current beam.

[0173] In some exemplary embodiments, UE 402 may use at least one parameter provided for beam selection reference signal and beam sounding reference signal resources to generate demodulation reference signals in uplink and downlink. As an example, such parameters may include identification parameters for determining a sequence.

[0174] In some exemplary embodiments, UE 402 may receive an indication from physical (or higher) layer signaling regarding the creation of a new beam process. The indication itself may be received with an existing beam process. As an example, such an indication may include downlink control signaling that triggers a random access procedure. Similar to other exemplary embodiments, resources for the new beam process may be provided in a subsequent random access response. Alternatively, the indication may directly allocate resources for the new beam process and may directly trigger reception and transmission on beam selection and beam sounding reference signals, respectively. In this case, the applicable timing advance may be the same as the existing beam process used to receive the indication.

[0175] In some exemplary embodiments, UE 402 may receive an indication from physical (or higher) layer signaling regarding the deletion of an existing beam process. UE 402 may perform measurements for the beam process. Such measurements enable UE 402 to identify the best beam within the beam process. For example, UE 402 may be configured to use a beam (current beam) within the beam process configuration. UE 402 may use this beam and other beam subsets (possibly beams within a subsequently defined beam group) to perform measurements. The measurement may be periodic and may be configured by the network. In another exemplary embodiment, such measurements may be non-periodic. For example, UE 402 may be triggered by its serving TRP to perform such measurements (possibly with the aid of a transmission using the beam process). In another example, measurements performed on a beam associated with a beam process may trigger the UE to perform such measurements on a beam group.

[0176] Once such measurements are performed, the UE 402 may determine that the new beam improves reception (and possibly transmission) from / to the TRP / cell / eNB. In this case, the UE 402 may autonomously update the beam process to include the new beam. The UE 402 may also indicate to the network (e.g., by means of a transmission using the beam process itself) that the UE 402 has changed its beam. Doing so enables the network to determine whether its own beam is still the best fit with the new UE beam. In another exemplary embodiment, once it is determined that the new beam can improve the performance of the beam process, the UE 402 may request the network to initiate a new beam selection process. Such a process may or may not require the UE 402 to use the newly determined beam.

[0177] Mobility-related aspects

[0178] Once measurements on a set of beams (beams within a beam group) are triggered, it is possible that the UE 402 may not be able to find a beam suitable for use within the beam process. For example, if measurements on the initial beam process configuration indicate that it cannot successfully transmit and / or receive data using the beam process, the UE 402 may therefore initiate a tuning process. This conclusion may be based on measurements that are less than a threshold. In this case, the UE 402 may be directed to find another beam to use within the beam process before continuing to use the beam process. If the UE 402 fails to obtain another beam within the beam group, it may perform at least one of the following actions: continue searching for beams in other beam groups or possibly in the same beam classification; continue searching for beams in other beam classifications or beam classifications that overlap with the previously selected beam; or declare a radio link failure (RLF) or beam link failure (BLF) for the beam process. Wherever RLF is used in this specification, it includes BLF.

[0179] If UE 402 determines RLF of a beam process, it may indicate the condition to at least one serving TRP. If UE 402 is still configured with a (e.g., non-RLF) working beam process, UE 402 may indicate the identity of the beam process that is experiencing RLF to the TRP. In one embodiment, UE 402 may carry the indication by transmitting an uplink beam recovery transmission. In addition, in the beam recovery transmission, UE 402 may request to switch to a target beam process (e.g., a working (e.g., non-RLF) beam process) in order to maintain the UE radio link. UE 402 may perform beam recovery transmission using pre-configured time / frequency / code / beam resources. For example, UE 402 may use an uplink transmit beam associated with a working (e.g., non-RLF) beam process. In another example, UE 402 may transmit a beam recovery transmission on a default UL beam. The beam recovery transmission may be repeated over multiple symbols, time slots, or transmissions so that a beam scanning process can be performed at the receiver. In another example, UE 402 may use uplink beams associated with all configured beam processes and transmit beam recovery transmissions in an uplink beam scanning manner. UE 402 may monitor and receive a switching command in downlink L1 control signaling. UE 402 may receive a switching command on a default beam pairing link (e.g., a wide beam and possibly an omnidirectional Tx and Rx beam pairing). The switching command may indicate resources available for UE 402 to perform beam capture. In another embodiment, the switching command may explicitly indicate to UE 402 one or more BPLs for an upcoming transmission. In another embodiment, UE 402 may monitor and receive a switching command in downlink L1 control signaling for a downlink beam associated with a switching target beam process.

[0180] If the UE no longer has any working beam process (for example, if the UE is configured with a single beam process and the beam process encounters RLF), the UE may perform a new initial beam process acquisition process. In another exemplary embodiment, the UE may be configured with a primary or main beam process. If RLF is declared on such a beam process, the UE may be triggered to perform a new initial beam process acquisition process. This process may remove all existing beam processes. During this process, the UE 402 may indicate to the network whether RLF has occurred on one (e.g., primary or main) beam process or on all beam processes (e.g., all beam processes associated with the TRP / cell / eNB).

[0181] In an exemplary embodiment, the initial beam process acquisition process may use a random access procedure. In this case, the UE 402 may be pre-configured with resources and / or preamble values ​​to perform a contention-free RA for the beam process acquisition (reacquisition) process. In another example, the UE may have a connection with a second TRP / cell / eNB. The second TRP / cell / eNB may provide the UE (possibly upon declaring RLF for one or all beam processes of the first TRP / cell / eNB) with random access resources (or preambles) to perform a contention-free random access.

[0182] UE 402 may maintain measurements on at least one mobility reference signal (MRS). Such mobility reference signals may be transmitted either per TRP or on orthogonal resources for each TRP. Mobility measurements may use a specific beam process (e.g., a beam process dedicated to such measurements). UE 402 may determine to add a new beam process. The determination may be triggered by: measurements on at least one MRS indicating the possibility of acquiring one or more new beam processes; UE 402 determining improved reception or transmission performance; the location of the UE; or RLF on one or more beam processes associated with the TRP / cell / eNB. UE 402 may improve reception or transmission performance by virtue of the improved diversity provided by the addition of the new beam process. In another exemplary embodiment, UE 402 may request that a new beam process enable transmission and reception similar to CoMP. For location, UE 402 may store its location relative to different TRPs and may determine that one or more new beam processes may be invoked from a new TRP. After determining to add a new beam process, UE 402 may indicate to the network the measurements made or an explicit indication of adding one or more new beam processes (or replacing an existing beam process with a new beam process). The indication may initiate a new beam process acquisition process.

[0183] If UE 402 can add a new beam process without removing other beam processes (e.g., if there are still unused TRX chains), then UE 402 can indicate that the new beam process can be added to the existing beam process list. Alternatively, the network can be informed of the UE's beam process capabilities and can start adding new beam processes without removing previous beam processes.

[0184] In another exemplary embodiment, UE 402 may indicate to the network that it cannot add a new beam process without removing an existing beam process or at least modifying the parameters of an existing beam process. In addition, UE 402 may indicate a request to add a new beam process to an existing beam process. For example, UE 402 may indicate that an existing beam process is configured for a subset of time resources. UE 402 may indicate a set (one or more) of beam processes to be used for such time resource restrictions.

[0185] UE 402 may indicate (possibly to a new TRP / cell / eNB) which time resources are configured for a new beam process. A new beam process may be configured for an orthogonal set of time resources. This configuration change enables the new beam process to coexist with previously configured beam processes.

[0186] UE 402 may maintain beam process sets. The elements of these sets may include beam processes that can be used simultaneously. The number of elements contained in such sets may be less than the maximum number of TRX chains of UE 402 or TRP / cell / eNB. A beam process may be included in more than one set. For example, UE 402 may have a first beam process with no time restrictions, a second beam process applicable to a first set of time resources, and a third beam process applicable to a second set of time resources orthogonal to the first set of time resources. In this case, UE 402 may maintain a first beam process set with a first and a second beam process set, and a second beam process set with a first and a third beam process. The time restrictions on previously configured beam processes and new beam processes may be appropriately maintained until further reconfigured by the network or until UE 402 requests a change in parameters regarding one or more beam processes.

[0187] In an exemplary embodiment, once a mobility event is triggered, the UE 402 may assume that a certain beam process (or all beam processes) may use a pre-configured set of time resources. The one beam process may be a primary beam process, or the time resources may be determined based on a beam process ID. The UE may perform a beam process acquisition process on time resources orthogonal to the time resources used for pre-existing beam processes. Once the mobility event ends, the UE 402 may assume that a new beam process is valid for all time resources and may completely remove the previously configured beam process that was restricted in the mobility event.

[0188] UE 402 may use different beam process acquisition methods depending on the reason for adding the beam process. For example, if the reason is to increase the number of beam processes (e.g., to improve diversity or multiplexing), UE 402 may attempt to acquire a new beam process based on rules associated with existing beam processes. In this example, UE 402 may test a restricted beam set (or beam group or beam classification) to acquire a new beam process. This restriction may ensure that a new beam process is added to an existing beam process set and that the new beam process is unlikely to be associated with an existing beam process.

[0189] In another example, if UE 402 requests to add a new beam (e.g., because of RLF), UE 402 may start the process using a specific beam group and / or classification. This approach may ensure that a new beam process is found in a shorter time, regardless of whether the new beam process optimizes transmission / reception performance. For example, a UE 402 that experiences RLF using a beam with a specific beam classification may attempt to acquire a new beam process using a beam with a higher or lower classification.

[0190] UE 402 may indicate to the network a request to add a beam process. The indication may include: a reason for adding a beam process; an existing beam process to be replaced by a new beam process; or a usage restriction of the beam process. As an example, the usage restriction may include a communication link direction (e.g., UL, DL, SL, or a combination thereof). In another example, the usage restriction may include a transmission type (e.g., mMTC, URLLC, eMBB). In another example, the usage restriction may include a beam process parameter (e.g., SOM or parameter configuration). In another example, the usage restriction may include the purpose of the beam process (e.g., for data transmission or for mobility measurement). In another example, the usage restriction may list a subset of time resources expected to be used by the beam process.

[0191] UE 402 may request to add or remove a beam process. The request may be made using resources dedicated to the serving TRP / cell / eNB. For example, the UE may use the beam process itself to transmit a request to remove the beam process. In another example, the UE may request to add a beam process to a TRP, thereby indicating the TRP ID (or any parameter obtained on the MRS) to the source TRP.

[0192] In an exemplary embodiment, UE 402 may request to add a new beam process by using a procedure similar to RA. UE 402 may transmit a random access preamble using the beam to be used for the new beam process. This transmission may trigger an operation where only TRP / cell / eNB beams will match the UE beam for that beam process. In another example, UE 402 may use beams from a specified RA with the appropriate beam classification. The guarantee procedure may force optimization of the UE's beams as well as the TRP / cell / eNB beams.

[0193] In another exemplary embodiment, UE 402 may have a dedicated beam and / or beam process (e.g., using RA) for transmitting a beam add request. Such a dedicated beam and / or beam process may be configured by the network. In another example, UE 402 may be configured to have one or more beam processes for a specific purpose. In addition, one or more such beam processes may be marked for use in additional beam process requests.

[0194] In some embodiments, UE 402 receives beam process transmission multiplexing configuration for simultaneous beam processes.

[0195] In some embodiments, UE 402 may be configured to transmit simultaneously for different TRPs when the associated beam processes may have the same signal configuration including subcarrier spacing, symbol length, resource block size, cyclic prefix length, etc. In such an embodiment, uplink beam transmissions for different TRPs may use the same frequency resources and may be spatially multiplexed, where the uplink beams are directed to the TRPs in a manner such that the isolation between beam patterns is above a pre-configured threshold. A potential benefit of this approach may be the reuse of frequency resources and the resulting high uplink spectral efficiency.

[0196] In another embodiment, uplink beam transmissions may be multiplexed using dedicated frequency resources for each beam process associated with different TRPs. The resulting uplink beam patterns may partially overlap and may result in reduced beamforming complexity.

[0197] Alternatively, UE 402 may use different orthogonal spreading codes for beam processes associated with different TRPs, and the code configuration for each TRP may be received.

[0198] Beam selection process

[0199] The following sections describe methods and example embodiments for performing beam selection. Although these example embodiments may be described from the perspective of a single beam or a single beam process, it should be understood that in practice, these processes may be applied to multiple beam processes in parallel.

[0200] Beam classification

[0201] The beam can be generally characterized in the manner described in Section 7.1.1 of 3GPP specification TR37.842, Radio Frequency Requirement Background for Active Antenna System Base Station, Release 13, v.1.8.0, October 2015. As mentioned above, Figure 3A and 3B The difference between the beam peak direction and the beam center direction is shown. The beam peak direction refers to the maximum point of the beam, while the beam center direction refers to the center point of the beam distribution.

[0202] Figure 5 The differences between beams 506, beam groups 508, and beam classes 502, 504 are shown. The figure also shows the differences between a lower beam class 502 and a higher beam class 504. A beam family in this example may include all beams of the same class.

[0203] Example embodiment for maintaining links between beam classes

[0204] Different beam classes may exhibit different levels of coverage. In general, the more directional the beam is, the better the coverage in a particular direction. This observation also means that there is often a trade-off between directionality and coverage. Wider beams may exhibit less coverage, which may be problematic for some types of traffic or control channels. When changing to a lower beam class, the UE may lose the radio link. Likewise, when the UE changes to a higher beam class, the UE may end up transmitting too much power for the specified rate.

[0205] In an exemplary embodiment, the UE may be configured to scale its transmission power according to the beam class. For example, a lower beam class may use more power (e.g., for a specified bit rate, transport format, or MCS) than other higher beam classes. As an example, this configuration may be implemented using a predefined power scaling factor associated with the beam class. While this approach results in similar received power at the eNB and the radio link may be maintained, it also limits the data rate per beam class because the power amplifier is typically power limited.

[0206] In an exemplary embodiment, the link may be maintained by using repetitions over multiple beams. For example, the UE may be configured to repeatedly transmit a specified data block over multiple beams (e.g., belonging to the same beam group) at multiple time instants. The UE may be configured to use a predefined beam sequence (e.g., within a beam group).

[0207] As an example, when the UE changes to a lower beam classification, this may trigger repeated processing through multiple beams. In an exemplary embodiment, this approach avoids segmentation due to a change in coverage caused by changing to a lower beam classification, and is only applied to HARQ retransmissions.

[0208] In an exemplary embodiment, the repetitive processing on multiple beams may be triggered and controlled by the network. For example, the UE may receive an indication on a control channel (e.g., DCI) to initiate repetitive processing on multiple beams. Optionally, the indication may include a beam classification and / or a beam group index for transmitting data. As an example, the indication may be accompanied by an indication to change to a lower beam classification.

[0209] In another example embodiment, the UE may be configured to indicate to the network (eg, UCI) when repeated processing on multiple beams is required (eg, when the UE has data in its retransmission buffer to be retransmitted via multiple beams).

[0210] For another example embodiment, the UE may transmit on a subset of beams at a time. More specifically, the UE may be configured to transmit repeated data on a subset of multiple beams within a single TTI. The UE may receive an ACK / NACK from the network and may continue to transmit the repeated data on another subset of the multiple beams. The UE may repeat this process until it receives an ACK from the network or until it has transmitted on all relevant beams.

[0211] Determine the set of available beams to choose from

[0212] The UE may be configured to select beams for transmission on its beam subset (also referred to as the available beam set). The beam subset may be configured by the network (e.g. in a semi-static manner (e.g. via RRC) or dynamically (e.g. via DCI type signaling).

[0213] In an exemplary embodiment, the UE may be configured to determine the available beam set based on the beam classification. For example, the UE may determine that an available beam set corresponds to a beam group (e.g., associated with a beam of a lower beam classification associated with a beam process). In another option, as an example, the UE may determine the beam group based on a direction of arrival of a downlink reference signal associated with the beam process. For example, the available beam set may be a beam group in a lower beam classification having a beam direction that is closest to a direction of arrival (DoA) of the downlink reference signal.

[0214] In an example embodiment, the UE may be configured to have an available beam set subject to angular restrictions. For example, these restrictions may apply to beam directions. The UE may be configured to restrict the beam directions of the available beam set to have a specific angular distance from the DoA of the downlink reference signal associated with the beam process.

[0215] In another example, the UE may be configured to use an arbitrary beam that is restricted to be within a specific beam space. The beam space may have its boundaries set using angle limits. For example, the UE may determine that the set of available beams includes any beam whose beam direction is within a set of values ​​(e.g., associated with the DoA of the downlink reference signal of the associated beam process). The UE may further apply one or more conditions because the beam has an arbitrary shape. In an exemplary embodiment, the UE may limit a specific energy of the beam (e.g., 90%) to a specific angle limit. For a specific angle limit. For example, these angle limits can be determined based on the network configuration and the angle difference (ΔDoA) applied to the DoA of the downlink reference signal associated with the beam process.

[0216] The UE may be configured to determine which beam classification to use for its uplink transmission. The network may configure the UE to use a specific beam classification (e.g., via DCI or via semi-static signaling (e.g., RRC)). In another exemplary embodiment, the UE may be configured to independently determine the most appropriate beam classification based on factors maintained by the UE.

[0217] The UE may determine the beam classification to use for transmission based on the transmitted data. For example, the UE may be configured to use one or more beam classifications for control information (e.g., RRC signaling or RACH access) and one or more beam classifications for data transmission. In another example, the UE may be configured to use one beam classification for each logical channel. The UE may use the beam classification associated with the logical channel being transmitted. The UE may also store rules to determine which beam classification to use when multiple logical channels with different associated beam classifications are multiplexed together. For example, the rule may use a lower beam classification in the beam classification associated with the logical channels multiplexed in the transport block.

[0218] In another example, the UE may be configured to use specific beam classifications for different service types (e.g., mMTC, eMBB, URLLC, or QoS). For example, the UE may be configured with beam classifications directly in the QoS configuration, or the UE may be configured with an association table or filter that associates QoS with specific beam classifications.

[0219] The UE may be configured to indicate to the network which beam classifications the UE uses in its UL transmissions. This information may be conveyed in the UCI or in a special MAC header or other types of signaling. The UE may indicate to the network only when it changes the beam classification or when the UE makes a decision on which beam classification to use.

[0220] In another exemplary embodiment, the eNB may explicitly configure the UE to use a specific beam class. For example, the eNB UL grant may indicate a specific beam class to be used for uplink beamforming. For this case, the beam class may be valid only for the duration of the grant. Alternatively, the UE may be semi-statically configured with the beam class to be used.

[0221] The UE and the network may synchronize the beam classification states so that the UE and the network are always aware of which beam classification is being used. There are multiple ways to achieve this synchronization. For one approach, the counterpart entity acknowledges all beam classification changes (e.g., at the MAC or RRC protocol level). In an example of this approach, the UE may indicate a beam classification change via a special MAC control element and apply the change only if it receives a reliable acknowledgement from the network (e.g., from a DL MAC control element).

[0222] The UE may maintain the beam classification configuration until it changes the configuration or until the UE receives a message from the network to change the configuration. The UE may be configured to change the beam classification immediately and acknowledge the network message in its next transmission (e.g., in a MAC header or other control message), or the UE may only acknowledge the network message and apply the change after receiving an acknowledgement from the network (e.g., a HARQ-ACK or other higher layer acknowledgement from the network).

[0223] In practice, the UE may be configured with multiple beam processes. Although the network may control the transmission direction of the associated downlink reference signal, each beam process should result in an independent propagation path in order to exploit the spatial diversity or spatial multiplexing capability of the channel. The UE will avoid transmitting data on the same propagation path (and thus on the beam) for different beam processes. When determining the set of available beams, the UE may be configured to exclude one or more beams associated with other ongoing or active beam processes.

[0224] The UE may be configured to determine the beam group associated with a specified beam process. The UE may create a list comprising: the same beam as the beam selected in the (other) beam process; beams in the beam group associated with the beam process; beams within the beam index range of the selected beam of the (other) beam process; and beams within the angular distance of the selected beam performed by the (other) beam. The beams in the beam group associated with the beam process include beam groups of lower beam classifications associated with the selected beam of the beam process. The range of beam indices may be configured a priori by the network or by a specification. For example, the beam range may include all beams within ±N beam indices of the selected beam.

[0225] The angular distance may be configured a priori by the network. Correlated beams include beams whose beam centers are within a certain maximum angular distance from the beam center of the selected beam of the (other) beam process (for the same beam classification). The maximum angular distance (e.g. in degrees or radians) may be configured by the network. For example, a correlated beam may be defined as any beam whose beam center is within ±Δmax of the beam center of the (other) beam process. Alternatively, a set of correlated beams may be defined based on the 3dB (or other value) beam lobes and beam centers of the selected beam of the (other) beam process. Any beam whose 3dB lobe falls within ±Δmax of the beam center of the selected beam of the (other) beam process may be considered correlated.

[0226] When more than one beam process is configured, the UE may be configured to select a beam outside the set of relevant beams for each beam process (considering all outer beam processes). The UE may be configured to select the best available (and non-relevant) beam.

[0227] In an exemplary embodiment, when the UE determines that the selected best beam falls within the relevant beam set and / or when the UE determines that the available beam set is empty, the UE may be configured to stop transmission on the associated beam process, or the UE may notify the network (e.g., through control signaling) by performing transmission on a different beam process with an available beam. The UE may further indicate a beam process number or identifier and the relevant beam or beam process.

[0228] Selection Process

[0229] The UE can determine the beam classification, beam group, and beam for uplink transmission based on measurements made on one or more downlink beams by using at least one of the following exemplary embodiments: quality / spatial / energy metrics, periodicity, downlink control / data / reference signal transmission, single-stage measurement, or multi-stage measurement.

[0230] Beam quality metrics can be measured based on SNR, E b / N o , RSSQ and CQI. Beam spatial information measurements can be based on angle of arrival (AoA). Beam energy metric measurements can be based on RSSI and wideband AGC settings.

[0231] Beam periodic measurements can be periodic or aperiodic, where beam measurements can be scheduled by the network. During active downlink data transmission, a measurement field or gap can be included in the measurement schedule. Beam measurements can be configured in system broadcast information or higher layer dedicated signaling including measurement period. The UE can be triggered to perform periodic measurements within a predefined period.

[0232] For downlink control / data / reference signal transmissions, beam measurements can be performed on downlink beams associated with downlink control information, downlink data transmissions, scheduled downlink reference signal transmissions (e.g., beam selection reference signals), or periodic downlink reference signal transmissions (e.g., beam selection reference signals).

[0233] Single-stage beam measurements may be measured using: one or more beams from a beam group of a beam classification pre-configured and selected by the UE for beam measurement, a beam classification based on the target measurement beam classification and the type of uplink transmission service for which the measurement will be used, or a beam scan applied in a continuous or arbitrary manner to cover the beam space where the target downlink beam can be received.

[0234] Multi-stage measurement can use the following to measure: one or more beams from a beam group of a first beam classification selected in a manner similar to a single-stage measurement, thereby obtaining a first measurement result; continuing the first measurement process to use the next measurement, and based on the first measurement result, using one or more beams of a second beam classification, wherein the second beam classification can have one or more different characteristics compared to the first beam classification (such as a reduced beam width or an adjusted center direction); or a multi-stage scan, wherein each stage can include a selected beam and the beam space can be gradually reduced as the UE determines the spatial information and quality metrics of the measured downlink beam.

[0235] Based on the measurement results, the UE can select at least one beam from a beam group of a certain beam classification for uplink transmission using: a connection between the beam classification used for measurement and the associated beam classification for uplink transmission, a calculation based on directional reciprocity, or a scan of multiple selected uplink beams in the beam space based on the measurement.

[0236] The association of the beam classification used for transmission and for measurement may be included in the beam process. In some exemplary embodiments, the UE may select an uplink beam with the same beam classification as the beam classification used for measurement. For example, the selected uplink beam may have a similar beam width, beam center direction, or beam space.

[0237] As an example, the directional reciprocity calculation may be between AoA and AoD. In an example embodiment, the UE may select an uplink beam from the beam classification based on the estimated downlink measured AoA information and beam width and by beam center direction calculation.

[0238] For scanning for multiple selected uplink beams, the UE may select a beam group with a different beam classification than the beam classification used for beam measurement and scanning over the measured downlink beam space.

[0239] The UE can set the beam-specific power for the selected beam based on measurements and other configurations including: the expected power offset associated with the measured beam classification signaled by the network, the uplink channel type and service used for uplink transmission, the priority and maximum limit of the selected beam classification, the maximum transmission power of each antenna element, the maximum EIRP of the UE uplink transmission, and an EIRP adjustment indication from the network (which the UE can use to adjust the beam classification or maintain the beam classification while adjusting the power on a component-by-component basis).

[0240] The UE may determine one or more of the beam classification, beam group and beam for uplink transmission based on the received feedback for the uplink beam sounding process. The sounding process may be scheduled and configured by the network. The configuration may include: antenna port configuration, beam classification indicator, number of sounding beams, time resource allocation, frequency resource allocation, reference signal configuration of the sounding beam, and EIRP of the sounding beam. The antenna port configuration indicates the port to be used. The beam classification indicator indicates which beam classification can be used for sounding on an antenna port by antenna port basis. The number of sounding beams indicates the number of sounding beams transmitted on an antenna port by antenna port basis. An exemplary embodiment of time resource allocation may allocate a field having multiple symbols in a control field of a subframe, or a gap having multiple symbols in a data segment of a subframe. In another exemplary embodiment, a special subframe may be configured for the sounding process. The exemplary frequency resource allocation may be a subcarrier or a resource block group. The exemplary reference signal configuration for the sounding beam may be a basic Zadoff-Chu (ZC) sequence for each antenna port or UE. The EIRP of the probing beam may include the beamforming gain and power of each antenna element.

[0241] The UE may select a sounding beam arbitrarily from the beam group for the indicated beam classification according to the number of configured sounding beams. The UE may apply the same ZC basis sequence to each sounding beam transmitted from the same antenna port. The ZC basis sequence may be configured per antenna port. The sounding beams for each antenna port may be transmitted one at a time. Different antenna ports may have sounding beams using different ZC basis sequences in order to maintain orthogonality.

[0242] In another exemplary embodiment, the ZC basis sequence may be configured according to the UE, where each antenna port may be assigned by the UE based on downlink beam measurement and by cyclic shift. For this case, the sounding beam reference signal may be orthogonal between the antenna ports of the UE.

[0243] The uplink beam sounding process can be triggered by pre-configured events, such as the UE entering backoff or the downlink data beam quality falling below a pre-configured threshold.

[0244] As described in subsequent exemplary embodiments, the UE may perform a multi-stage uplink beam sounding process for several scenarios. For one exemplary embodiment, the UE may be configured with a multi-stage sounding process request, wherein each stage of the sounding process uses a series of beam classifications. The configuration may include time resources and reference signal configurations for each beam classification. In another exemplary embodiment, the UE may autonomously determine a series of beam classifications and may use a predefined set of reference signal sequences reserved for autonomous uplink beam sounding processing so that the network can detect the sounding beam. The UE may receive network feedback in the control information received from the downlink beam. Such feedback control information may have a fixed timing relationship with the sounding beam transmission timing, and the UE may monitor the feedback based on the timing relationship. In another exemplary embodiment, the feedback may be included in the scheduled downlink data. The feedback content may be a bit map for indicating which sounding beam can be received above a threshold and can be used for further sounding. The feedback may also include sounding beam metric information and reference signal indexes for these sounding beams. The UE may decide which beam classification to use based on the received feedback. In an exemplary embodiment, the UE may use beam classification according to a configured beam classification sequence. The UE transmits the next set of sounding beams in the beam space of the previous sounding beams with feedback above a threshold. The network may configure new resource allocations for each stage, or alternatively, the network may apply the same resources until the multi-stage sounding process ends.

[0245] The UE may select an uplink beam based on the best sounding beam indicated in the feedback of the uplink beam sounding process. In another exemplary embodiment, the network may schedule one or more beams of beam classification based on the uplink beam sounding process. The UE may receive the uplink beam and beam classification configuration in the downlink control information.

[0246] The network may schedule beams of different beam classes for each antenna port according to the uplink and service type of the uplink transmission. For example, the network may schedule one beam class for uplink control information transmission on one antenna port and another beam class for data transmission on another antenna port. The scheduling process may be accomplished using one or more fields in the DCI for indicating beams or beam classes.

[0247] Transmit beams may be multiplexed in both the time and frequency domains. For example, in one subframe, a UE may use one beam classification in the uplink control field and a different beam classification in the uplink data field. In another exemplary embodiment, a UE may transmit simultaneous beams of different beam classifications, each of which may apply different subcarriers or resource block groups.

[0248] The power of each beam class may be determined based on feedback from the uplink beam sounding process. Each beam class may have an independent maximum EIRP and a maximum transmit power per antenna element. The power control of each beam may be limited by the maximum EIRP of the beam class.

[0249] For a particular uplink channel transmission, the network may configure a beam class-specific power control command for it. The UE may adjust the transmission power on a component-by-component basis. In another exemplary embodiment, the network may configure a different beam class for the uplink transmission, and the UE may adjust the transmission power of each component according to the new beam class. For example, the reconfigured beam class may have a wider beam width, and the UE may increase the transmission power to maintain the overall EIRP.

[0250] The network can schedule uplink beams and beam classifications to maximize uplink transmission capacity and avoid uplink transmission interference between co-scheduled UEs. In the process of maximizing uplink transmission capacity, the network can use uplink beams based on beam classification that achieves the best detection results with a very narrow beam width. This process can improve the spectral efficiency of a single user. As an example, in the process of avoiding uplink transmission interference, the network can evaluate the uplink beam detection results from all UEs that can perform transmissions for the same TRP, and can select beams and beam classifications for each UE so that the transmit beam of one UE is empty in the direction toward the main lobe direction of the transmit beam of the co-scheduled UE. This technology enables co-scheduled UEs to use the same time, frequency, and code resources, and can improve the average spectral efficiency of each TRP.

[0251] The UE can trigger the uplink fallback procedure in multiple scenarios, such as when it receives a ramped-up TPC bit and reaches the maximum EIRP for the beam classification while receiving a downlink NACK for a data beam transmission, when it receives a predetermined number of NACK messages for a specific uplink beam used for data transmission, or when it enters a beam uncalibrated state based on pre-configured criteria.

[0252] The UE fallback procedure may include the following operations: stopping using the currently selected beam and beam classification, selecting another beam classification to continue uplink data transmission, setting the transmission power of each component according to the selected beam classification, and starting the uplink sounding procedure using predefined resources.

[0253] When another beam classification is selected to continue uplink data transmission, the new beam classification can be the lowest beam classification or a beam classification with a predefined offset lower than the used beam classification. And as an example, the new beam classification can have a wider beam width or a different beam center direction.

[0254] As an example, when setting the transmit power of each component according to the selected beam class, the UE can increase the transmit power to compensate for the reduced beamforming gain when using a lower beam class. When the maximum power of the component is reached, the UE can provide cumulative gain by applying a beam scanning process.

[0255] The process of initiating the uplink beam sounding process using predefined resources may include reserving a reference signal sequence for a fallback trigger for uplink beam sounding and allocating preconfigured time and frequency resources for the fallback trigger for uplink beam sounding. As an example, the symbol and subframe positions may be calculated based on the UE and TRP identifiers used for the sounding process.

[0256] In another exemplary embodiment, the UE may send a fallback indicator to the network using an uplink beam of a different beam classification (e.g., a beam used for uplink control information transmission from another antenna port). The uplink beam used for control transmission may encounter unrelated blocking or channel events and may be used. The UE may receive an uplink sounding beam request and configuration to initiate the uplink sounding process. The resource configuration may not be retained and may be dynamically configured. In another exemplary embodiment, the UE may receive an initial beam process request.

[0257] Maximum Power Reduction (MPR) caused by SAR

[0258] The UE may receive human monitoring information including detected distance and angular direction from the motion sensor. The UE may determine which uplink beams are likely to be located in a predetermined proximity of a detected human body by collating the human body detection data. The UE may autonomously apply a maximum power reduction (MPR) (e.g., having a predefined value) to each identified uplink beam. It should be noted that the maximum power may represent the total effective isotropic radiated power (EIRP) radiated by the uplink beam pattern.

[0259] The UE may perform maximum power reduction using one or more of a variety of different techniques. In one technique, the UE backs off the maximum transmit power of each of all antenna elements associated with the identified uplink beam. In another technique, the number of antenna elements used for the identified uplink beam is reduced. It should be noted that this process may be implemented in a UE that has the ability to scale the number of antenna elements used for analog beamforming. The reduction in antenna elements may also result in changes in beam classification. In another technique, the UE may switch to a different set of antennas located at the opposite end (if it has such capability; this may occur in frequency bands above 6 GHz) in order to keep the radiation pattern at optimal power.

[0260] The UE may autonomously determine how to reduce the overall EIRP. In some embodiments, the network may pre-configure information related to how to perform MPR for UEs with antenna component scalability.

[0261] The UE may be configured with an indication of which method should be applied to reduce the maximum EIRP (e.g., whether the reduction should be applied by reducing the maximum power or by reducing the number of antenna elements). This configuration may be provided by higher layer signaling.

[0262] Beam Process Parameter Update

[0263] The UE may further identify which active beam process may be associated with the uplink beam with the SAR induced MPR and may update the relevant parameters of the identified beam process. The beam process specific parameters may include the updated maximum total EIRP, maximum configured power, resulting power margin, and beam classification. The beam classification change may cause the UE to update the estimation of the interference within the uplink beam received at the TRP.

[0264] PHR triggered by MPR caused by SAR

[0265] For each beam process identified, the UE may be triggered to send a report, for example indicating the number of beams with at least the maximum EIRP and / or P cmax A power headroom report (PHR) or EIRP report with new parameters applicable to the maximum power adjusted for the changed beam process. In the report, the UE can specify that the MPR cause is associated with SAR and can indicate the identity of the affected beam process. The report can be transmitted as control information on the physical layer. In the latter case, the control information can be associated with the same or different beam processes. The potential benefits of using UCI transmission can be low latency and overhead, as MPR caused by SAR will become more frequent in beamforming operations of HF NR. In another embodiment, the UE can use MAC or RRC signaling to transmit the report. Maximum gain offset report triggered by MPR caused by SAR

[0266] The UE may be configured or autonomously apply MPR by reducing the number of antenna elements and thereby reducing the beamforming gain of the beam process. The UE may keep the power of each element unchanged. The UE may be triggered to report a maximum gain offset report to indicate the offset between the applied beam gain and the maximum gain of the configured beam process. The eNB may trigger uplink beam reselection for the beam process. In another solution, the eNB may reduce the transport format (e.g., coding rate and modulation scheme) for the beam process for which the beamforming gain is reduced in order to maintain the radio link. Doing so may improve the robustness of the beam processing during MPR.

[0267] SAR-triggered beamforming reselection

[0268] The UE may reselect an active beam process with updated parameters and PHR due to the MPR caused by SAR. Uplink beam reselection may be done according to a set of preconfigured rules. The UE may apply rules based on the uplink transmission type of the beam process, the updated uplink transmission, the uplink channel type, and the uplink transmission mode and scheme. In some exemplary embodiments, the UE may change the beam process association by establishing a new beam process or switching to another active beam process with a new set of downlink and uplink beams.

[0269] Uplink beam reselection for active beam process affected by SAR

[0270] UE 602 may reselect an uplink beam of an active beam that is processed due to MPR caused by SAR. Figure 6 The illustrated example embodiment 600 shows that due to the proximity of beam B2 (606) to a human body 608, the UE 602 can reselect beam B1 (604) to replace beam B2 (606) for the active beam process. The UE 602 can consider the reduced maximum EIRP and MRP in the open loop selection process of the uplink beam. For example, the UE 602 can apply a negative EIRP reduction to an uplink beam that corresponds in a reciprocal manner to an active downlink beam associated with the beam process. As a result, the UE 602 will not select an uplink beam that is reciprocal to the active downlink beam associated with the beam process. The UE 602 will not select another uplink beam based on reciprocity, but based on the adjusted maximum EIRP of the available uplink beams (including the uplink beam affected by SAR). The UE 602 can also fall back to a default uplink beam that is pre-selected and maintained for the beam process.

[0271] UE 602 may re-estimate the path loss of the reselected uplink beam. The "paired" downlink beam for each beam process may be either a downlink data beam, a reference beam, or another type of downlink beam. This pairing is not necessarily a one-to-one mapping, and the path loss estimation may use the transmission power specified in the system broadcast information. The uplink power of the reselected uplink beam may be based on the re-estimated path loss. In another solution, the uplink power may be implicitly indicated by a periodic synchronization signal sequence.

[0272] UE 602 may reestablish the transmit timing of the reselected uplink beam. In addition, beam reselection may trigger uplink beam scanning using updated power, and UE 602 may initiate uplink beam pairing and beam recapture procedures. The beam recapture process may not be based on the associated downlink beam using reciprocity. UE 602 may update the re-paired downlink and uplink beams for the associated beam process. UE 602 may send beam process update information to the eNB using the reselected uplink beam transmission.

[0273] Beam processing triggered by rotation or blocking sensing data: uplink beam reselection and re-pairing

[0274] The UE 602 may periodically estimate the azimuth change of the antenna array and may update a local coordinate system used as a reference for the beam direction. The estimation by the UE 602 may be based on rotation and blockage sensing data provided by the motion sensor.

[0275] UE 602 can autonomously fallback one or more transmission attributes, including transmission mode, transmission scheme, beamforming attributes, etc. For example, UE 602 can apply a pre-configured wide beam width or omni-directional beam width. The increased beam width can allow part of the uplink transmission energy to reach the eNB by diffraction around the detected blockage. In addition, the wide beam pattern can reduce the impact of the rotation of UE 602. In addition, UE 602 can use a pre-configured uplink control and data channel transmission format, which includes a block size and a modulation and coding scheme (MCS). Due to the widening of the beam width, the overall EIRP will be reduced, and UE 602 can use a smaller block size and a conservative MCS to maintain uplink quality.

[0276] In another embodiment, the UE 602 may initiate an uplink sounding transmission using an uplink beam scanning process using a predefined uplink sounding configuration. The configuration may include a reference signal type and a resource allocation. Doing so may allow the UE 602 to identify an uplink beam that is likely not affected by the rotation or detected blocking. The UE 602 may reselect an uplink beam based on the results of the initiated uplink sounding process. After the sounding process, the UE 602 may transmit a measurement or uplink beam re-pairing request.

[0277] Once rotation and blocking are detected, a UE 602 with multiple simultaneously active beam processes may initiate uplink beam reselection and re-pairing processes on a beam process-by-beam process basis. The UE 602 may apply orthogonal uplink resource configurations in the frequency domain or time domain for uplink fallback and re-pairing transmissions. In another solution, the UE 602 may have two spatially isolated simultaneous beam processes, and in this case, the UE 602 may use the same frequency and time resources for beam process transmissions.

[0278] Downlink RLF Avoidance

[0279] Blocking may be the cause of UE downlink RLF, and UE 602 may use the rotation vector and rate estimation to predict the situation. UE 602 may determine whether the rotational movement or detected blocking will cause RFL in the near time frame by applying rules or criteria. The rules may include SINR degradation rate, received energy reduction, and BLER increase. UE 602 may use a control channel with a predefined transmission format to transmit a preconfigured sequence to trigger the downlink beam reselection process. In another solution, UE 602 may no longer apply autonomous transmission based on sensing data, in which case UE 602 may turn off all uplink transmit beams and may suspend active beam processes. Doing so will prevent UE 602 from consuming energy to operate under adverse channel conditions (e.g., with very fast rotational motion, very high speed, or with a large blocker moving towards UE 602 at a very fast speed). Under these conditions, beamforming transmission may not be feasible.

[0280] Downlink detection and adjustment

[0281] UE 602 may request beam-specific reference signal transmission for downlink beam adjustment. UE 602 may monitor the quality metric of the downlink beam associated with the active beam process during active data reception. The quality metric may include energy detection within the active beam pair on the assigned frequency resources, DMRS symbol energy above noise, sensed rotation amplitude. When the monitored quality metric exceeds a predetermined threshold, UE 602 may send a request for BSRS transmission. Beam-specific reference signal resource configuration may be pre-configured, and UE 602 may initiate a new beam pairing process using receive beam scanning based on a detected BRS. UE 602 may determine and update the receive beam associated with the active beam process.

[0282] UE 602 can detect the receive beam in a periodic manner or triggered by a predefined event for each active beam process. During active downlink data transmission, UE 602 can perform receive beamforming detection processing on a TTI-by-TTI basis or on multiple TTIs evenly distributed in a predefined time period. The UE can use either a CP or GP attached to each symbol or a field specific to the subframe structure where there is no useful data transmission, especially for a single receive beam UE. The time period can also be scheduled as a special subframe or a block of one or more symbols. UE 602 can also perform detection on the UW on a UE waveform without a CP or GP. For a multi-receive beam UE, the time period can overlap with data transmission (e.g., data and DMRS symbols).

[0283] The receive beamforming detection process may include performing a complete receive beam scan for a predefined receive beam group (e.g., adjacent receive beams (GOB) or + / -x degrees (continuous BF)), and / or re-cycling the best receive beam previously used. The UE 602 may measure the energy detected for each receive beam adjusted, and find the best receive beam according to a predefined criterion.

[0284] The sounding period can be short to reduce measurement overhead. Analog measurements do not require reference signal transmission for a specific waveform and may require a shorter sounding time. As a result of the sounding, the UE 602 can use receive beam selection to update the active beam process.

[0285] UE 602 may also adjust the receive beam associated with the active beam process based on the results of the rotation detection and receive beamforming measurement of UE 602. UE 602 may use the continuous analog beamforming capability to autonomously track the receive beam tracking process. Similar to the receive beam sounding configuration, UE 602 may perform receive beamforming adjustments in a predefined period. UE 602 may determine the adjustment based on the measured rotation vector, the energy change (wideband AGC value) of the detected active beam pairing, the receive channel SINR using the active beam pairing, the channel quality measured during the receive beamforming measurement, and the like. UE 602 may apply the updated receive beam and continue to perform active data reception without knowing the TRP. UE 602 may update the active beam process due to the receive beam adjustment, and may maintain a beam pairing mapping between one or more receive beams and one transmit beam.

[0286] The UE can determine the "best beam" based on measuring the energy on a set of resources using a set of candidate beams.

[0287] In some embodiments, a resource set may be a specific time period or sequence of symbols within a downlink data transmission for UE 602. The existence of the resource set may be indicated in the downlink control information applicable to the transmission or may be configured by a higher layer. In some solutions, the information mapped on the resource set may be encoded and / or modulated using parameters that are different from the parameters of the remaining resources of the transmission, thereby increasing the probability of successful decoding even when a suboptimal beam is used. The applicable parameters (e.g., code rate, modulation, or modulation coding scheme index) may be indicated by the downlink control information or configured by a higher layer, or may be implicitly determined from the parameters used for the remaining resources (e.g., a predetermined or preconfigured offset to the MCS index applied to the remaining portion of the transmission).

[0288] Network Architecture

[0289] Systems and methods involving multicast group construction can be used with reference to Figures 7A-7F The wireless communication systems described are used in combination. First, these wireless systems will be described. Fig. 7A is a diagram of an example communication system 700 in which one or more disclosed embodiments may be implemented. The communication system 700 may be a multiple access system that provides content such as voice, data, video, messaging, broadcast, etc. to multiple wireless users. The communication system 700 allows multiple wireless users to access such content by sharing system resources, including wireless bandwidth.

[0290] like Fig. 7A As shown, the communication system 700 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, and / or 102d (generally referred to as WTRUs 102), a radio access network (RAN) 103 / 104 / 105, a core network 106 / 107 / 109, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, but it should be appreciated that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network components. Each WTRU 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. For example, WTRU102a, 102b, 102c, 102d can be configured to transmit and / or receive wireless signals and may include: user equipment (UE), mobile station, fixed or mobile subscriber unit, pager, cellular phone, personal digital assistant (PDA), smart phone, laptop computer, netbook, personal computer, wireless sensor and consumer electronic device, etc.

[0291] The communication system 700 may also include a base station 114a and a base station 114b. Each base station 114a, 114b may be any type of device configured to facilitate access to one or more communication networks, such as the core network 106 / 107 / 109, the Internet 110, and / or the network 112, by wirelessly interfacing with at least one of the WTRUs 102a, 102b, 102c, 102d. By way of example, the base stations 114a and 114b may be base transceiver stations (BTS), Node Bs, eNode Bs, Home Node Bs, Home eNode Bs, site controllers, access points (APs), wireless routers, and the like. Although each base station 114a and 114b is depicted as a single component, it is contemplated that the base stations 114a and 114b may include any number of interconnected base stations and / or network components.

[0292] The base station 114a may be part of the RAN 103 / 104 / 105, and the RAN may also include other base stations and / or network components (not shown), such as a base station controller (BSC), a radio network controller (RNC), a relay node, and the like. The base station 114a and / or the base station 114b may be configured to transmit and / or receive wireless signals within a specific geographic area called a cell (not shown). The cell may be divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three cell sectors. Thus, in one embodiment, the base station 114a may include three transceivers, that is, each transceiver corresponds to a sector of the cell. In another embodiment, the base station 114a may use multiple-input multiple-output (MIMO) technology, and thus multiple transceivers may be used for each sector of the cell.

[0293] The base stations 114a, 114b may communicate with one or more WTRUs 102a, 102b, 102c, and 102d over an air interface 115 / 116 / 117, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 115 / 116 / 117 may be established using any suitable radio access technology (RAT).

[0294] More specifically, as described above, the communication system 700 may be a multiple access system and may use one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, and SC-FDMA, among others. For example, the base station 114a in the RAN 103 / 104 / 105 and each of the WTRUs 102a, 102b, 102c may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may use Wideband CDMA (WCDMA) to establish the air interface 115 / 116 / 117. WCDMA may include communication protocols such as High Speed ​​Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High Speed ​​Downlink Packet Access (HSDPA) and / or High Speed ​​Uplink Packet Access (HSUPA).

[0295] In another embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 115 / 116 / 117 using Long Term Evolution (LTE) and / or LTE-Advanced (LTE-A).

[0296] In other embodiments, the base station 114a and the WTRUs 102a, 102b and 102c can implement radio access technologies such as IEEE 802.16 (Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE) and GSM EDGE (GERAN).

[0297] As an example, Fig. 7AThe base station 114b in the example may be a wireless router, a Home NodeB, a Home eNodeB, or an access point, and may use any appropriate RAT to facilitate wireless connectivity in a local area, such as a business location, a residence, a vehicle, a campus, etc. In one embodiment, the base station 114b and the WTRUs 102c and 102d may establish a wireless local area network (WLAN) by implementing a radio technology such as IEEE802.11. In another embodiment, the base station 114b and the WTRUs 102c and 102d may establish a wireless personal area network (WPAN) by implementing a radio technology such as IEEE 802.15. In yet another example, the base station 114b and the WTRUs 102c, 102d may establish a picocell or a femtocell by using a cellular-based RAT, such as WCDMA, CDMA2000, GSM, LTE, LTE-A, etc. Fig. 7A As shown, the base station 114b may be directly connected to the Internet 110. Thus, the base station 114b may not necessarily need to access the Internet 110 via the core network 106 / 107 / 109.

[0298] The RAN 103 / 104 / 105 may be in communication with a core network 106 / 107 / 109, which may be any type of network configured to provide voice, data, applications, and / or Voice over Internet Protocol (VoIP) services to one or more WTRUs 102a, 102b, 102c, 102d. For example, the core network 106 / 107 / 109 may provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, video distribution, etc., and / or perform high-level security functions such as user authentication. Although in Fig. 7A It is not shown, but it will be appreciated that the RAN 103 / 104 / 105 and / or the core network 106 / 107 / 109 may be in direct or indirect communication with other RANs that employ the same RAT or a different RAT as the RAN 103 / 104 / 105. For example, in addition to being connected to the RAN 103 / 104 / 105 employing E-UTRA radio technology, the core network 106 / 107 / 109 may also be in communication with another RAN (not shown) employing GSM radio technology.

[0299] The core network 106 / 107 / 109 may also act as a gateway for the WTRUs 102a, 102b, 102c, and 102d to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network that provides plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer network devices that use common communication protocols, such as the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP), and the Internet Protocol (IP) in the TCP / IP Internet protocol suite. The networks 112 may include wired and / or wireless communication networks owned and / or operated by other service providers. For example, the networks 112 may include another core network connected to one or more RANs, which may use the same RAT or a different RAT as the RAN 103 / 104 / 105.

[0300] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communication system 700 may include multi-mode capabilities, that is, each of the WTRUs 102a, 102b, 102c, and 102d may include multiple transceivers for communicating with different wireless networks over different wireless links. Fig. 7A The illustrated WTRU 102c may be configured to communicate with the base station 114a, which may employ a cellular-based radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology.

[0301] Figure 7B 1 is a system diagram of the RAN 103 and the core network 106 according to one embodiment. As described above, the RAN 103 may employ a UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 115. The RAN 103 may also be in communication with the core network 106. Figure 7B As shown, the RAN 103 may include Node-Bs 140a, 140b, 140c, each of which may include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c via the air interface 115. Each of the Node-Bs 140a, 140b, 140c may be associated with a particular cell (not shown) within the RAN 103. The RAN 103 may also include RNCs 142a, 142b. It will be appreciated that the RAN 103 may include any number of Node-Bs and RNCs while remaining consistent with the embodiment.

[0302] like Figure 7BAs shown, Node B 140a, 140b can communicate with RNC 142a. In addition, Node B 140c can also communicate with RNC 142b. Node B 140a, 140b, 140c can communicate with corresponding RNC 142a, 142b via Iub interface. RNC 142a, 142b can communicate with each other via Iur interface. Each RNC 142a, 142b can be configured to control the corresponding Node B 140a, 140b, 140c connected thereto. In addition, each RNC 142a, 142b can be configured to perform or support other functions, such as outer loop power control, load control, admission control, packet scheduling, switching control, macro diversity, security functions and data encryption, etc.

[0303] Figure 7B The illustrated core network 106 may include a media gateway (MGW) 144, a mobile switching center (MSC) 146, a serving GPRS support node (SGSN) 148, and / or a gateway GPRS support node (GGSN) 150. Although each of the foregoing components are described as being part of the core network 106, it should be appreciated that entities other than the core network operator may own and / or operate any of these components.

[0304] The RNC 142a in the RAN 103 may be connected to the MSC 146 in the core network 106 via an IuCS interface. The MSC 146 may be connected to the MGW 144. The MSC 146 and the MGW 144 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices.

[0305] The RNC 142a in the RAN 103 may also be connected to the SGSN 148 in the core network 106 via an IuPS interface. The SGSN 148 may in turn be connected to the GGSN 150. The SGSN 148 and the GGSN 150 may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0306] As described above, the core network 106 may also be connected to the networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers.

[0307] Figure 7C1 is a system diagram of the RAN 104 and the core network 107 according to one embodiment. As described above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. In addition, the RAN 104 may also be in communication with the core network 107.

[0308] The RAN 104 may include eNode-Bs 160a, 160b, 160c, however it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. Each of the eNode-Bs 160a, 160b, 160c may include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the eNode-Bs 160a, 160b, 160c may implement MIMO technology. Thus, for example, the eNode-B 160a may use multiple antennas to transmit wireless signals to, and receive wireless signals from, the WTRU 102a.

[0309] Each eNodeB 160a, 160b, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, user scheduling in the uplink and / or downlink, and the like. Figure 7C As shown, the eNode-Bs 160a, 160b, 160c may communicate with one another over an X2 interface.

[0310] Figure 7C The illustrated core network 107 may include a mobility management entity (MME) 162, a serving gateway 164, and a packet data network (PDN) gateway 166. Although each of the above components are described as being part of the core network 107, it should be understood that entities other than the core network operator may also own and / or operate any of these components.

[0311] The MME 162 may be connected to each of the eNode-Bs 160a, 160b, 160c in the RAN 104 via an S1 interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, activating / deactivating bearers, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, and the like. The MME 162 may also provide a control plane function to facilitate handover between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM or WCDMA.

[0312] The serving gateway 164 may be connected to each of the eNode-Bs 160a, 160b, 160c in the RAN 104 via an S1 interface. The serving gateway 164 may generally route and forward user data packets to / from the WTRUs 102a, 102b, 102c. The serving gateway 164 may also perform other functions, such as anchoring the user plane during inter-eNode-B handovers, triggering paging when downlink data is available for the WTRUs 102a, 102b, 102c, managing and storing the context of the WTRUs 102a, 102b, 102c, and the like.

[0313] The serving gateway 164 may also be connected to the PDN gateway 166, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0314] The core network 107 may facilitate communications with other networks. For example, the core network 107 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks such as the PSTN 108 to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. As an example, the core network 107 may include or communicate with an IP gateway, such as an IP Multimedia Subsystem (IMS) server, which serves as an interface between the core network 107 and the PSTN 108. The core network 107 may also provide the WTRUs 102a, 102b, 102c with access to the networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers.

[0315] Fig.7D 1 is a system diagram of the RAN 105 and the core network 109 according to one embodiment. The RAN 105 may be an access service network (ASN) that communicates with the WTRUs 102a, 102b, 102c over the air interface 117 using IEEE 802.16 radio technology. As discussed further below, communication links between the different functional entities of the WTRUs 102a, 102b, 102c, the RAN 104, and the core network 109 may be defined as reference points.

[0316] like Fig.7DAs shown, the RAN 105 may include base stations 180a, 180b, 180c and an ASN gateway 182, but it should be appreciated that the RAN 105 may include any number of base stations and ASN gateways while remaining consistent with the embodiment. Each base station 180a, 180b, 180c may be associated with a particular cell (not shown) in the RAN 105, and each base station may include one or more transceivers to communicate with the WTRUs 102a, 102b, 102c via the air interface 117. In one embodiment, the base stations 180a, 180b, 180c may implement MIMO technology. Thus, for example, the base station 180a may use multiple antennas to transmit wireless signals to the WTRU 102a, and receive wireless signals from the WTRU 102a. The base stations 180a, 180b, 180c may also provide mobility management functions, such as handover triggering, tunnel establishment, radio resource management, traffic classification, quality of service (QoS) policy enforcement, and the like. The ASN gateway 182 may act as a traffic aggregation point and may be responsible for implementing paging, subscriber profile caching, routing to the core network 106, and the like.

[0317] The air interface 117 between the WTRUs 102a, 102b, 102c and the RAN 105 may be defined as an R1 reference point implementing the IEEE 802.16 specification. In addition, each of the WTRUs 102a, 102b, 102c may establish a logical interface (not shown) with the core network 109. The logical interface between the WTRUs 102a, 102b, 102c and the core network 109 may be defined as an R2 reference point (not shown), which may be used for authentication, admission, IP host configuration management, and / or mobility management.

[0318] The communication link between each base station 180a, 180b, 180c may be defined as an R8 reference point, which includes protocols for facilitating WTRU handovers and data transfer between base stations. The communication link between the base stations 180a, 180b, 180c and the ASN gateway 182 may be defined as an R6 reference point. The R6 reference point may include protocols for facilitating mobility management based on mobility events associated with each WTRU 102a, 102b, 180c.

[0319] like Fig.7DAs shown, the RAN 105 may be connected to a core network 109. The communication link between the RAN 105 and the core network 109 may be defined as an R3 reference point, which, as an example, includes protocols for facilitating data transfer and mobility management capabilities. The core network 109 may include a mobile IP home agent (MIP-HA) 184, an authentication authorization accounting (AAA) server 186, and a gateway 188. Although each of the aforementioned components is described as being part of the core network 109, it should be understood that an entity other than the core network operator may also own and / or operate any of these components.

[0320] The MIP-HA 184 may be responsible for implementing IP address management and may allow the WTRUs 102a, 102b, 102c to roam between different ASNs and / or different core networks. The MIP-HA 184 may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The AAA server 186 may be responsible for implementing user authentication and supporting user services. The gateway 188 may facilitate interworking with other networks. For example, the gateway 188 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional landline communications devices. In addition, the gateway 188 may also provide the WTRUs 102a, 102b, 102c with access to the networks 112, which may include other wired and / or wireless networks that are owned and / or operated by other service providers.

[0321] Although in Fig.7D Not shown, but understood, the RAN 105 may be connected to other ASNs, and the core network 109 may be connected to other core networks. The communication link between the RAN 105 and the other ASNs may be defined as an R4 reference point (not shown), which may include protocols for coordinating the mobility of the WTRUs 102a, 102b, 102c between the RAN 105 and the other ASNs. The communication link between the core network 109 and the other core networks may be defined as an R5 reference point (not shown), which may include protocols for facilitating interworking between a home core network and a visited core network.

[0322] Fig. 7E is a system diagram illustrating an example WTRU 102. Fig. 7EAs shown, the WTRU 102 may include a processor 118, a transceiver 120, a transmit / receive component 122, a speaker / microphone 124, a numeric keypad 126, a display / touchpad 128, a non-removable memory 130, a removable memory 132, a power supply 134, a global positioning system (GPS) chipset 136, and other peripheral devices 138. The transceiver 120 may be implemented as a component of the decoder logic 119. For example, the transceiver 120 and the decoder logic 119 may be implemented on a single LTE or LTE-A chip. The decoder logic may include instructions that are operable to be executed and stored in a non-transitory computer-readable medium. Alternatively or additionally, the decoder logic may be implemented using custom and / or programmable digital logic circuits.

[0323] It should be appreciated that the WTRU 102 may also include any sub-combination of the foregoing components while remaining consistent with the embodiments. Furthermore, the embodiments contemplate that each of the base stations 114a and 114b and / or the nodes represented by the base stations 114a and 114b (for example, but not limited to, a transceiver station (BTS), a Node B, a site controller, an access point (AP), a Home Node B, an evolved Home Node B (eNode B), a Home Evolved Node B (HeNB), a Home Evolved Node B gateway, and a proxy node) may be included in the Fig. 7E Some or all of the components depicted in and described herein.

[0324] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC) and state machine, etc. The processor 118 may perform signal coding, data processing, power control, input / output processing, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. Although Fig. 7E The processor 118 and the transceiver 120 are depicted as separate components, however it is contemplated that the processor 118 and the transceiver 120 may be integrated into one electronic component or chip.

[0325] The transmit / receive component 122 can be configured to transmit or receive signals to or from a base station (e.g., base station 114a) via an air interface 115 / 116 / 117. For example, in one embodiment, the transmit / receive component 122 can be an antenna configured to transmit and / or receive RF signals. In another embodiment, as an example, the transmit / receive component 122 can be an emitter / detector configured to transmit and / or receive IR, UV or visible light signals. In yet another embodiment, the transmit / receive component 122 can be configured to transmit and receive RF and light signals. It should be understood that the transmit / receive component 122 can be configured to transmit and / or receive any combination of wireless signals.

[0326] In addition, although Fig. 7E 102 as a single component, but the WTRU 102 may include any number of transmit / receive components 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit / receive components 122 (e.g., multiple antennas) for transmitting and receiving radio signals via the air interface 115 / 116 / 117.

[0327] The transceiver 120 may be configured to modulate signals to be transmitted by the transmit / receive element 122 and to demodulate signals received by the transmit / receive element 122. As described above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers that allow the WTRU 102 to communicate via multiple RATs, such as UTRA and IEEE 802.11.

[0328] The processor 118 of the WTRU 102 may be coupled to a speaker / microphone 124, a keypad 126, and / or a display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit), and may receive user input data from these components. The processor 118 may also output user data to the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128. In addition, the processor 118 may access information from and store information in any suitable memory, such as a non-removable memory 130 and / or a removable memory 132. The non-removable memory 130 may include a random access memory (RAM), a read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 118 may access information from, and store data in, memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0329] The processor 118 may receive power from the power source 134, and may be configured to distribute and / or control power for use by other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries (e.g., nickel-cadmium (Ni-Cd), nickel-zinc (Ni-Zn), nickel-metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, and the like.

[0330] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) related to the current location of the WTRU 102. In addition to or in lieu of the information from the GPS chipset 136, the WTRU 102 may receive location information from a base station (e.g., base stations 114a, 114b) via the air interface 115 / 116 / 117 and / or determine its location based on the timing of signals received from two or more nearby base stations. It should be appreciated that the WTRU 102 may acquire location information via any suitable positioning method while remaining consistent with an embodiment.

[0331] The processor 118 may be further coupled to other peripherals 138, which may include one or more software and / or hardware modules that provide additional features, functionality, and / or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (for photos or videos), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands-free headset, modules, FM radio units, digital music players, media players, video game console modules, and Internet browsers, among others.

[0332] Figure 7F Describes a Fig. 7A 1 and 2. The exemplary network entity 190 used within the communication system 700 of FIG. Figure 7F As shown, the network entity 190 includes a communication interface 192 , a processor 194 , and a non-transitory data storage 196 , all of which are communicatively connected via a bus, network, or other communication path 198 .

[0333] The communication interface 192 may include one or more wired communication interfaces and / or one or more wireless communication interfaces. For wired communication, the communication interface 192 may include one or more interfaces, such as an Ethernet interface. For wireless communication, the communication interface 192 may include components such as one or more antennas, one or more transceivers / chipsets designed and configured for one or more types of wireless (e.g., LTE) communications, and / or any other components deemed appropriate by technicians in the relevant field. Further, for wireless communication, the communication interface 192 may be equipped at a scale and may be equipped with a configuration suitable for the network end (relative to the client) acting on wireless communication (e.g., LTE communication and Wi-Fi communication, etc.). Thus, the communication interface 192 may include appropriate devices and circuits (possibly including multiple transceivers) to provide services for multiple mobile stations, UEs, or other access terminals in the coverage area.

[0334] Processor 194 may include one or more processors of a type deemed appropriate by persons skilled in the relevant art(s), some examples of which include general purpose microprocessors and special purpose DSPs.

[0335] The data storage 196 may be in the form of any non-transitory computer-readable medium or a combination of these media, some examples of which include flash memory, read-only memory (ROM), and random access memory (RAM), etc. However, any one or more types of non-transitory data storage that a person skilled in the relevant art deems appropriate may be used. Figure 7FAs shown, data memory 196 contains program instructions 197 that are executable by processor 194 to perform various combinations of the various network entity functions described herein.

[0336] In some embodiments, the network entity functions described herein are performed by a Figure 7F In some embodiments, one or more of these functions are performed by a combination of multiple network entities, each of which has a similar structure to the network entity 190. Figure 7F The structure of the network entity 190 is similar to the structure. In various different embodiments, the network entity 190 is or includes at least one or more of the following: RAN 103 (one or more entities), RAN 104 (one or more entities), RAN 105 (one or more entities), core network 106 (one or more entities), core network 107 (one or more entities), core network 109 (one or more entities), base station 114a, base station 114b, Node B 140a, Node B 140b, Node B 140c, RNC 142a, RNC 142b, MGW 144, MSC 146, SGSN 148, GGSN 150, eNode B 160a, eNode B 160b, eNode B 160c, MME 162, Serving Gateway 164, PDN Gateway 166, Base Station 180a, Base Station 180b, Base Station 180c, ASN Gateway 182, MIP-HA 184, AAA 186 and gateway 188. Of course, in different embodiments, other network entities and / or combinations of network entities may be used to perform the network entity functions described herein, and the foregoing list is provided as an example rather than a limitation.

[0337] Although features and components in specific combinations are described above, it will be recognized by those skilled in the art that each feature or component may be used alone or in any combination with other features and components. In addition, the methods described herein may be implemented in a computer program, software, or firmware that is introduced into a computer-readable medium for operation by a computer or processor. Examples of computer-readable media include electrical signals (transmitted via a wired or wireless connection) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, read-only memory (ROM), random access memory (RAM), registers, buffer memory, semiconductor storage devices, magnetic media (such as internal hard disks and removable disks), magneto-optical media, and optical media (such as CD-ROM discs and digital versatile discs (DVDs)). A processor associated with the software may be used to implement a radio frequency transceiver used in a WTRU, UE, terminal, base station, RNC, or any computer host.

[0338] Abbreviations used

[0339] Δf Subcarrier spacing

[0340] 5gFlex 5G Flexible Radio Access Technology

[0341] 5gNB 5GFlex Node B

[0342] ACK

[0343] BB Baseband

[0344] BLER Block Error Rate

[0345] BTI Basic TI (an integer multiple of one or more symbol durations)

[0346] CB Contention-based (e.g., access, channel, resource)

[0347] CoMP Coordinated Multi-Point Transmission / Reception

[0348] CP Cyclic Prefix

[0349] CP-OFDM Conventional OFDM (depends on cyclic prefix)

[0350] CQI Channel Quality Indicator

[0351] CSI Channel State Information

[0352] CN Core Network (e.g. LTE Packet Core)

[0353] CRC Cyclic Redundancy Check

[0354] CSI Channel State Information

[0355] CSG Closed Subscriber Group

[0356] D2D device-to-device transmission (e.g. LTE sidelink)

[0357] DCI Downlink Control Information

[0358] DL Downlink

[0359] DM-RS Demodulation Reference Signal

[0360] DRB Data Radio Bearer

[0361] ERIP equivalent isotropic radiated power

[0362] EPC Evolved Packet Core

[0363] FB Feedback

[0364] FBMC filter bank multicarrier

[0365] FBMC / OQAM uses FBMC technology with offset quadrature amplitude modulation

[0366] FDD Frequency Division Duplex

[0367] FDM Frequency Division Multiplexing

[0368] ICC Industrial Control and Communications

[0369] ICIC Inter-cell Interference Cancellation

[0370] IP Internet Protocol

[0371] LAA Authorized Assisted Access

[0372] LBT Listen before you speak

[0373] LCH Logical Channel

[0374] LCP Logical Channel Prioritization

[0375] LLC low latency communication

[0376] LTE Long Term Evolution, e.g. from 3GPP LTE R8 and above

[0377] MAC Media Access Control

[0378] NACK Negative ACK

[0379] MBB Massive Broadband Communications

[0380] MC Multi-Carrier

[0381] MCS Modulation and Coding Scheme

[0382] MIMO Multiple Input Multiple Output

[0383] MTC Machine Type Communication

[0384] NAS Non-Access Stratum

[0385] OFDM Orthogonal Frequency Division Multiplexing

[0386] OOB Out of Band (Radio)

[0387] P cmax Total available UE power in a given TI

[0388] PHY Physical Layer

[0389] PRACH Physical Random Access Channel

[0390] PDU Protocol Data Unit

[0391] PER Packet Error Rate

[0392] PLMN Public Land Mobile Network

[0393] PLR Packet Loss Rate

[0394] PSS Primary Synchronization Signal

[0395] QoS Quality of Service (from the perspective of the physical layer)

[0396] RAB Radio Access Bearer

[0397] RACH Random Access Channel (or process)

[0398] RF Radio Front End

[0399] RLF Radio Link Failure

[0400] RNTI Radio Network Identifier

[0401] RRC Radio Resource Control

[0402] RRM Radio Resource Management

[0403] RS reference signal

[0404] RTT Round Trip Time

[0405] SCMA Single Carrier Multiple Access

[0406] SDU Service Data Unit

[0407] SL Side Link

[0408] SOM Spectrum Operating Mode

[0409] SS Sync Signal

[0410] SSS Secondary synchronization signal

[0411] SRB Signalling Radio Bearer

[0412] SWG Switching Gap (in self-contained subframe)

[0413] TB Transfer Block

[0414] TDD Time Division Duplex

[0415] TDM Time Division Multiplexing

[0416] TI time interval (one or more integer multiples of BTI)

[0417] TTI Transmission Time Interval (one or more integer multiples of TI)

[0418] TRP Transmission / Reception Point

[0419] TRX Transceiver

[0420] UE User Equipment

[0421] UFMC Universal Filtered Multi-Carrier

[0422] UF-OFDM Universal Filtered OFDM

[0423] UL Uplink

[0424] URC Ultra Reliable Communications

[0425] URLLC Ultra-Reliable and Low-Latency Communications

[0426] V2V Vehicle-to-Vehicle Communication

[0427] V2X vehicle-to-vehicle communications

[0428] WLAN Wireless Local Area Network and related technologies (IEEE 802.xx field)

[0429] ZC Zadoff-Chu sequence

Claims

1. A method for use by a wireless transmit / receive unit (WTRU) comprising a plurality of antenna elements, the method comprising: receiving, by the WTRU (602), configuration information indicating a plurality of beam processes, wherein at least one of the plurality of beam processes has a corresponding identifier, wherein the at least one of the plurality of beam processes is associated with a downlink reference signal, and wherein the at least one of the plurality of beam processes is provisioned with resources for the downlink reference signal, the provisioned resources comprising an indication of time and frequency resources; receiving, by the WTRU, downlink control information including an indication of the corresponding identifier of the at least one beam process of the plurality of beam processes; selecting, by the WTRU, a beam process from the plurality of beam processes based on the indication of the corresponding identifier of the at least one beam process in the plurality of beam processes received in the downlink control information; as well as The WTRU performs uplink transmission using the selected beam process.

2. The method according to claim 1, comprising: and receiving by the WTRU using the selected beam process, wherein using the selected beam process includes applying a set of precoding weights associated with the downlink reference signal.

3. The method according to claim 1, comprising: Additional beam processes are configured in response to an indication received by the WTRU from a transmission reception point.

4. The method of claim 1 , wherein configuring the WTRU using the at least one beam process from among the plurality of beam processes comprises: Measurements are performed on a downlink reference signal.

5. A method according to claim 4, wherein a corresponding beam process of at least one beam process among the multiple beam processes is associated with a beam process used for transmission, and wherein the beam process used for transmission is determined by the WTRU by performing measurements on the downlink reference signal.

6. A wireless transmit / receive unit (WTRU) (602), comprising any of a plurality of antenna elements, a transmitter, a receiver, a processor, and a memory, the WTRU being configured to: receiving, by the WTRU (602), configuration information indicating a plurality of beam processes, wherein at least one of the plurality of beam processes has a corresponding identifier, wherein the at least one of the plurality of beam processes is associated with a downlink reference signal, and wherein the at least one of the plurality of beam processes is provisioned with resources for the downlink reference signal, the provisioned resources comprising an indication of time and frequency resources; receiving downlink control information, the downlink control information comprising an indication of the corresponding identifier of the at least one beam process of the plurality of beam processes; selecting a beam process from among the plurality of beam processes based on the indication of the corresponding identifier of the at least one beam process in the plurality of beam processes received in the downlink control information; and Uplink transmission is performed using the selected beam process.

7. A WTRU according to claim 6, which is configured to receive using the selected beam process, wherein using the selected beam process includes applying a set of precoding weights associated with the downlink reference signal.

8. The WTRU of claim 6, wherein the WTRU is configured to configure an additional beam process in response to an indication received by the WTRU from a transmission reception point.

9. The WTRU of claim 6, wherein configuring the WTRU using the at least one of the beam processes comprises performing measurements on a downlink reference signal.

10. A WTRU according to claim 9, wherein a corresponding beam process of at least one of the multiple beam processes is associated with a beam process for transmission, and wherein the beam process for transmission is determined by the WTRU by performing measurements on the downlink reference signal.

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