Base station, user equipment and user equipment method

Abstract

Disclosed are a base station, a user equipment, and a method for the user equipment. The base station includes: a data storage device configured to store data corresponding to a first codebook and a second codebook, the first codebook being different from the second codebook; and one or more processors configured to precode a reference signal to be sent to a user equipment (UE); and precode data streams on a common resource element using the second codebook to prevent the data streams from interfering with each other.

Description

[0001] Division Statement

[0002] This application is a divisional application of the invention patent application with PCT international application number PCT / US2018 / 030250, international application date April 30, 2018, application number 201880029910.9 entering the Chinese national phase, and invention name “Management of MIMO Communication Systems”.

[0003] Related applications

[0004] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 502,036, filed May 5, 2017, which is hereby incorporated by reference herein in its entirety. Technical Field

[0005] This application generally relates to the field of wireless communications. Background Art

[0006] Various embodiments may generally relate to the field of wireless communications. Summary of the Invention

[0007] According to some aspects of the present application, a base station is provided, comprising: a data storage device configured to store data corresponding to a first codebook and a second codebook, the first codebook being different from the second codebook; and one or more processors configured to precode a reference signal to be sent to a user equipment (UE); and precode data streams on a common resource element using the second codebook to prevent the data streams from interfering with each other.

[0008] According to other aspects of the present application, a user equipment (UE) is provided, including: a data storage device configured to: store a first beamforming codebook and a second beamforming codebook different from the first beamforming codebook; and a processing circuit configured to: use the first beamforming codebook to reduce or compress the size of a receive beam space of multiple antennas of the UE; and use the second beamforming codebook to filter a data-bearing signal received from a cellular base station.

[0009] According to further aspects of the present application, a method of a user equipment (UE) is provided, comprising: storing sample data indicating information measured from a uniformly sampled receive beam space; estimating one or more parameters of a plurality of receive beams of a codebook based on the sample data; selecting a receive beam from the codebook based on the estimated one or more parameters; and receiving data from a cellular base station using the selected receive beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1is a simplified diagram showing the probability that a transmit / receive point (TRP) detects the correct beamforming vector for each UE.

[0011] Figure 2 is a simplified graph of the cumulative distribution function of the network spectral efficiency of a multi-user multiple-input multiple-output (MU-MIMO) millimeter-wave (mm-Wave) system according to some embodiments.

[0012] Figure 3 is a simplified signal flow diagram illustrating a measurement, feedback, and estimation protocol in a wireless communication system according to some embodiments.

[0013] Figure 4 is a simplified illustration of the number of measurements used to select beams using sector-level scanning compared to the proposed method disclosed herein.

[0014] Figure 5 ∝ ( ) is a graph showing the probability that a receiving node (eg, UE) detects a beam that maximizes the beamforming gain through the acquired M samples according to some embodiments.

[0015] Figure 6 is a simplified signal flow diagram illustrating signaling for selecting a receiving node in a wireless communication system according to some embodiments.

[0016] Figure 7 is a simplified diagram illustrating acquisition of information about a receive beam in a system using a receive sector level scanning (RXSS) system and in a system according to the proposed method.

[0017] Figure 8 is a simplified diagram of a wireless network according to some embodiments.

[0018] Figure 9 is a simplified illustration of a frame structure according to some embodiments.

[0019] Figure 10 is a simplified signal flow diagram illustrating a CSI acquisition scheme according to some embodiments.

[0020] Figure 11 The architecture of a network system according to some embodiments is shown.

[0021] Figure 12 Example components of a device according to some embodiments are shown.

[0022] Figure 13 An example interface of a baseband circuit according to some embodiments is shown.

[0023] Figure 14 is a diagram of a control plane protocol stack according to some embodiments.

[0024] Figure 15 Components of a core network according to some embodiments are shown.

[0025] Figure 16 is a block diagram illustrating components according to some example embodiments.

[0026] Figure 17 is a simplified flow chart illustrating a method of operating a wireless communication node in accordance with some embodiments.

[0027] Figure 18 is a simplified flow chart illustrating a method of operating a wireless communication device in accordance with some embodiments. DETAILED DESCRIPTION

[0028] The following detailed description refers to the accompanying drawings. The same reference numerals in different figures may identify the same or similar elements. In the following description, specific details, such as specific structures, architectures, interfaces, technologies, etc., are set forth for the purpose of explanation rather than limitation, so as to provide a thorough understanding of various aspects of the various embodiments. However, it will be apparent to those skilled in the art who benefit from this disclosure that various aspects of the various embodiments may be practiced in other examples that deviate from these specific details. In some cases, descriptions of well-known devices, circuits, and processes are omitted to avoid obscuring the description of the various embodiments with unnecessary details. For the purposes of this document, the phrase "A or B" refers to (A), (B), or (A and B).

[0029] As the number of antennas per network node increases, advanced channel-adaptive transmission strategies such as multi-user multiple-input multiple-output (MIMO) (MU-MIMO) or coordinated multi-point transmission (CoMP) are key to increasing the spectral efficiency of wireless networks. To implement advanced channel-adaptive transmission strategies, information about the wireless channel (e.g., channel state information (CSI)) may be obtained by a transmitting node (sometimes referred to herein as a "transmit / receive point" (TRP)). Examples of a TRP are cellular base stations or radio access network (RAN) nodes (e.g., evolved NodeB (eNB), next-generation NodeB (gNB), etc.).

[0030] The embodiments disclosed herein can address the measurement, estimation, and feedback of CSI in multi-user massive MIMO systems. The embodiments can minimize the measurement and feedback overhead to effectively implement advanced channel adaptive transmission strategies.

[0031] There are challenges in addressing the measurement, estimation and feedback of CSI in multi-user massive MIMO systems. In 3GPP, beam management and CSI feedback are two processes. Beam management is defined by a set of L1 / L2 procedures to acquire and maintain a set of TRPs and / or UE beams that can be used for downlink (DL) and uplink (UL) transmission and reception. Given the beam configuration, CSI measurements are performed and transmission parameters are determined. Since the beam is fixed before a scheduling decision is made, transmission strategies that require joint optimization of the beam and other transmission parameters cannot be implemented. In traditional implementations, the flexibility of the transmitter and therefore the implementation of advanced channel adaptive transmission schemes may be limited. Another traditional implementation involves Wireless Gigabit (WiGig).

[0032] The Beam Optimization Protocol (BRP) spends a lot of effort measuring the channel matrix at the receiver so that the beam can be optimized. In traditional implementations, this may not scale well with the number of antennas. The number of measurement signals required scales linearly with the number of antennas.

[0033] Traditional implementations may address measurement, estimation, quantization, and feedback separately:

[0034] To measure wireless channels, reference signals (RSs) can be sent from all antenna ports using orthogonal resources so that the channel between any pair of antenna ports can be measured.

[0035] • The UE uses these measurements to estimate some representation of the radio channel.

[0036] • The UE spends a lot of effort to quantize the channel estimate.

[0037] • Finally, the CSI is sent back to the TRP, which decides the transmission parameters based on this information.

[0038] Traditional academic approaches apply compressed sensing to the problem of massive MIMO channel estimation and reference. These methods rely on the sparsity of the channel and aim to reconstruct the entire channel. Traditional algorithms for decoding compressed sensing measurements can be computationally too complex to support efficient real-time implementation. Furthermore, traditional compressed sensing-based methods rely on the assumption that certain structure is present in the channel and often fail if this structure is altered or absent.

[0039] Embodiments disclosed herein may include processes for measuring CSI, feeding back CSI, and inferring from CSI. In some embodiments, a measurement protocol may be implemented that uniformly samples the channel space and simultaneously performs dimensionality reduction of the channel space. In some embodiments, the receiver may not attempt to estimate the channel. Instead, the receiver may mirror the measurements back to the transmitter. In some embodiments, the transmitter may find transmission parameters by estimating scheduling metrics without reconstructing the channel space (e.g., a channel matrix).

[0040] Embodiments of the present disclosure may have one or more of the following advantages:

[0041] Scaling the number of transmit antennas. For example, TRPs with a large number (e.g., thousands) of transmit antennas can be supported.

[0042] Compared to traditional implicit and explicit feedback schemes, measurement overhead can be reduced by up to 90%. Adequate channel measurements can be generated without having to send orthogonal RSs from each antenna port.

[0043] Additional beamforming codebooks can be used during the measurement phase. Thus, measurement and transmit codebooks can be optimized for their intended purpose. For example, the transmit codebook can be optimized for coverage and beamforming gain without limiting the number of elements. The measurement codebook can be optimized to enable accurate estimation with the minimum number of measurements.

[0044] The complexity of channel estimation can be significantly reduced, and the UE does not need to perform complex channel estimation processes. The complexity and delay at the UE can be reduced. The computationally complex tasks are moved to the TRP (i.e., infrastructure).

[0045] • The TRP may have all degrees of freedom for user scheduling and network control. The processing at the TRP may be performed by a linear real-time capability estimation scheme.

[0046] As will be discussed below, in some embodiments, the measurement and feedback protocol can enable the network to perform very close to optimal MU-MIMO with ideal CSI. For example, consider the following system settings in Table 1:

[0047] Table 1

[0048] #TRP RF 8 #TRPAntenna 128 (16 per RF) #UE Antenna 1 #UE 4 Channel Model 3GPP Line of Sight (LOS) Transmission codebook OFT codebook with 128 elements Measurement codebook Random codebook with M (parameter) elements Carrier frequency 73GHz Transmit SNR -20dB 5th percentile Rx SNR ≈4dB Scheduler Greedy max rate

[0049] Figure 11 is a simplified graph 100 illustrating the probability that the TRP detects the correct beamforming vector (e.g., the beamforming vector with maximum beamforming gain) for each UE. Simplified graph 100 includes a first graph 102 corresponding to a measurement plus quantization noise of -∞dB, a second graph 104 corresponding to a measurement plus quantization noise of -15dB, and a third graph 106 corresponding to a measurement plus quantization noise of -10dB. The x-axis (horizontal axis) illustrates the reduction in measurement overhead ratio compared to a beam scanning scheme using 128 beams (which may include 128 measurements). The y-axis (vertical axis) illustrates the probability of detection. As shown in graph 100, with a measurement plus quantization noise of -15dB (or less) (second graph 104), the measurement and feedback overhead can be reduced by nearly 90% without sacrificing a high probability of detection.

[0050] Figure 2 200 is a simplified diagram of cumulative distribution functions 202, 204, 206, 208, 210, and 212 (CDFs 202, 204, 206, 208, 210, and 212) of the network spectral efficiency of a MU-MIMO millimeter wave (mm-Wave) system according to some embodiments. The system parameters are as shown in Table 1 above. CDFs 202, 204, 206, 208, 210, and 212 correspond to resource signal (RS) numbers 4, 8, 16, 32, 64, and ideal CSI 128, respectively. In some embodiments, scheduling can be performed in a greedy manner based on signal-to-interference-plus-noise ratio (SINR) estimates. In some embodiments, measurement and feedback noise can be assumed to be zero. In some embodiments, a greedy scheduler can schedule multiple UEs on the same resource as long as the estimated spectral efficiency increases. In some embodiments, user separation in the spatial domain can be enforced through beamforming based on a wideband analog codebook and digital subband nulling.

[0051] In some embodiments, 16 reference signals (16RS) (corresponding to CDF 206) can provide sufficient information to achieve very close to ideal CSI performance. In some embodiments, this can significantly reduce measurement and feedback overhead, as traditional beam management schemes involve 128 measurements. Thus, in some embodiments, an 87.5% overhead reduction can be achieved.

[0052] For example, consider a wireless network with a single TRP and multiple UEs. In this example, assume that each UE has a single receive antenna and the TRP is equipped with N antennas. For ease of presentation, assume a block fading channel model such that the channel from the TRP to the UE can be represented by the vector h i ∈C NIn some embodiments, linear beamforming may be used for TRP and the possible beamforming vectors w are given by the codebook Note that most beamforming schemes with limited feedback constraints can be referred to as beamforming schemes with fixed transmit codebooks.

[0053] In some embodiments, the TRP can optimize the channel adaptive transmission strategy without estimating the channel at the UE or the TRP. In some embodiments, this can be achieved by feeding back certain measurements from the UE to the TRP. Figure 3 Example implementations of some such embodiments of the measurement, feedback, and estimation protocols are shown in .

[0054] Figure 3 3 is a simplified signal flow diagram illustrating a measurement, feedback, and estimation protocol in a wireless communication system 300 according to some embodiments. The wireless communication system 300 includes a TRP 302 and a UE 304. These and some related embodiments can be summarized as follows:

[0055] • The TRP 302 may transmit (306) RS (eg, non-orthogonal RS) sequences to the UE 304 from all antenna ports simultaneously.

[0056] • The UE 304 may measure (308) the received signal resulting from the RS (eg, received in a CSI-RS slot).

[0057] • The UE 304 may directly quantize (310) the received signal.

[0058] • The UE 304 may feed back (312) the measurements to the TRP.

[0059] • The TRP 302 may estimate (314) a scheduling utility function (also referred to herein as a "network utility function") that depends on certain network parameters (e.g., certain transmission strategies, number of selected users, assignment of users to precoding vectors, etc.).

[0060] • TRP 302 performs (316) network control.

[0061] • The TRP 302 sends a demodulation reference signal (DMRS) to the UE 304.

[0062] • The UE 304 decodes the DMRS (320).

[0063] • The UE 304 estimates (322) the channel.

[0064] • The UE 304 equalizes (324) the signal.

[0065] • The UE 304 decodes (326) the data from the signal.

[0066] Below are provided various aspects of embodiments of the processing measurement, feedback, and estimation protocols in more detail. For ease of presentation, these aspects may focus on a baseband channel model. However, in some embodiments, an extended wideband channel model or two other models may be used.

[0067] Examples of Measurements

[0068] In some embodiments, during the measurement phase, the TRP 302 may use M resource elements (denoted as CSI-RS ports) to simultaneously transmit a sequence of M RSs from all antenna ports (or subsets). For example, assuming that N antenna ports are used to transmit pilot signals (e.g., RSs), the signal transmitted on the mth resource element may be represented by an N-dimensional row vector The jth element of the pilot signal sent is represented by It can be given by a complex number transmitted by the jth antenna element on the mth resource element. All M pilot signals are collected in the so-called measurement matrix For the embodiments disclosed herein, the measurement matrix is ​​an M×N matrix and M<<N. Most conventional schemes (such as BRP in WiGig) assume that the measurement matrix is an orthogonal N×N matrix.

[0069] Feedback Examples

[0070] In some embodiments, for the purpose of describing the feedback protocol, an arbitrary but fixed UE may be considered. The signal received by the UE in the mth CSI-RS port may be represented by Given, where n im is additive noise. The M-dimensional measurement vector containing all received signals from all CSI RS ports can be written as In some embodiments, the vector y i can be directly quantized and fed back to the TRP, so that the feedback message from UE i that can be used for the TRP can be z i =y i +q i , where q i It can be additive quantization noise.

[0071] These embodiments are in contrast to conventional feedback schemes that use the measurement vector y to estimate the channel or some representation of the channel before generating the feedback message.Thus, in some embodiments, UEs with less computational power than conventional UEs may be used.

[0072] Example of estimation

[0073] In some embodiments, based on feedback messages z from multiple UEs i=1, 2, ..., K i , TRP can estimate various utility functions. In some embodiments, it can be estimated to depend on the effective channel gain The utility function of the effective channel gain is related to the channel hi and the beamforming vector w. This can be achieved by defining the quantized measurement z i and the beamforming vector w function f(z i ,w) to promote, this function can approximate the effective channel gain Examples include the Signal to Interference and Noise Ratio (SINR), which can be measured by Given, where w i is the beamforming vector assigned to UE i, w j is the beamforming vector assigned to UEs scheduled on the same resource element.

[0074] In some embodiments, another example may be leakage interference power ∑ j≠i f(z j ,w j ) 2 The function f(z j ,w j ) can be implemented in many ways. The function can be implemented in the form The linear function is given by, where Ψ is a measurement matrix that can depend on An N×M matrix.

[0075] Another class of functions can be given by convex optimization algorithms (e.g., constrained l1 minimization), which are often found in the context of compressed sensing applications.

[0076] Machine learning algorithms can also be used to implement the estimation function. In this case, the function can be trained or learned based on a training set. Ultimately, the estimation function can depend on the available context information, the computational power of the TRP, and other constraints, such as the desired estimation latency or accuracy.

[0077] Receive beam management

[0078] Future wireless systems will use wireless transceivers with a large number of physical antennas. The high power consumption and cost of the radio frequency (RF) chain prevent the use of traditional digital MIMO baseband beamforming techniques. Hybrid digital-analog beamforming schemes divide the beamforming between the analog and digital domains. In the analog domain, beamforming schemes can be implemented using power- and cost-efficient techniques. Because the analog beamforming processing occurs before the RF chain and the analog-to-digital converter (ADC), the signal received at a single antenna cannot be observed. This signal can only be observed after the analog receive beamforming. Therefore, the MIMO channel cannot be measured directly at the receiver. To determine the optimal receive filter, a codebook of receive beamforming vectors is defined, and an exhaustive search is performed on all codebook elements. To fully utilize the combining gain, the number of codebook elements typically scales with the number of physical receive antennas. Therefore, the measurement overhead scales with the number of receive antennas, and for a large number of antennas, a significant pilot signal overhead results.

[0079] The core of most conventional schemes is to define a codebook of receive beamforming vectors and perform an exhaustive search (e.g., sector-level scanning) over all codebook elements. More efficient schemes perform the search in multiple stages.

[0080] In WiGig, sector-level scanning is used to determine the optimal receive beamforming vector. The so-called beam optimization protocol (BRP) is used to further optimize the beamforming vector. BRP involves sending another sequence of reference signals so that the receiver can measure the effective channel after simulating receive beamforming.

[0081] In 3GPP New Radio (NR), it has been agreed that a set of L1 / L2 procedures will be specified to acquire and maintain a set of transmit and receive beams. The most likely first implementation will rely on sector-level scanning.

[0082] In academia, there have been many proposals to apply compressed sensing to the massive MIMO channel estimation problem. These methods usually rely on the structure or sparsity of the channel and usually aim to reconstruct the entire channel matrix or the channel covariance matrix.

[0083] The problem of transmit beam management based on a compressed measurement protocol has been considered. A compressed sensing-inspired scheme has been proposed that employs a compressed sensing-based measurement protocol but relies on a simple linear scheme for reconstruction. This scheme significantly reduces the number of measurements (e.g., by up to 90%) while enabling the transmitter to detect the optimal analog transmit beamforming vector with high probability.

[0084] Conventional solutions proposed in WiGig and 3GPP utilize huge measurement overhead or greatly limit the flexibility of the receiver.

[0085] Beamforming training in IEEE 802.11ad WiGig is divided into two phases. First, during the sector-level sweep (SS), the initial transmit / receive beams are determined. In the subsequent beam optimization phase (BRP), the selected beams are optimized. In 3GPP NR, SS-based procedures are being discussed for beam training. BRP is not excluded. Note that in some schemes, receiving SS is also considered an important step in obtaining the initial UE receive beamforming direction, as it avoids the UE from scanning a large number of directions during the responder SS phase of WiGig.

[0086] During receive sector level sweep (RXSS), the transmitting node sends RS on the most known transmit beam to allow the receiving node to test the best receive beam. The potential receive beams are represented by N CB The beamforming codebook definition of elements. For each receive beam measurement, at least one RS needs to be sent by the transmitting node. Therefore, the receive beamforming codebook is usually designed to have a small number of elements.

[0087] The algorithms used to decode compressed sensing measurements are computationally too complex to support efficient real-time implementations. Furthermore, methods based on compressed sensing rely on the assumption that certain structure (e.g., sparsity, low rank) is available in the channel and typically fail if such structure does not exist.

[0088] This paper discloses a method that enables a receiver to obtain a much smaller number of measurements M < < N CB According to N CB A method for determining an optimal receive beamforming vector using a codebook of elements, and related apparatus and systems. The optimal receive beamforming vector can be determined without prior knowledge of previously used receive beamforming vectors or position information. However, prior knowledge can be used to further reduce the number of measurements.

[0089] The embodiments disclosed herein significantly reduce measurement overhead. In fact, the number of resources required to allocate for beam management can be significantly less than the number of potential receive beams. As will be discussed below, measurement overhead can be reduced by up to approximately 96% compared to an exhaustive search.

[0090] The embodiments disclosed herein are designed for use in massive MIMO systems, including 3GPP NR and IEEE 802.11ad WiGig. These embodiments minimize measurement overhead to effectively implement channel-adaptive reception strategies, such as hybrid analog-digital beamforming.

[0091] The embodiments disclosed herein allow a receiving node (e.g., a UE) to determine the best receive beam from a beamforming codebook without having to measure every potential receive beam. The number of measurements performed in such an embodiment can be much smaller than the number of potential receive beams. In fact, the codebook element N can be made CB The number of (ie, potential receive beams) is very large without increasing the number of measurements.

[0092] Figure 4 is a simplified illustration comparing the number of measurements used to select an off beam using sector level scanning 400A and the proposed method 400B disclosed herein. Figure 4 The measurement overhead and codebook size are compared. Figure 4 As shown, in the sector-level scan 400A, N CB Measurement 402A is used to measure the CB A selected beam 406A is selected from the beams 404A. Figure 4 As shown, in the proposed method 400B, only M measurements 402B are used to obtain the N CB A beam 406B is selected from the beams (for example, M can be much smaller than N CB ).like Figure 4 As shown, the proposed method 400B enables selection using fewer measurements and a codebook (CB) with higher resolution (eg, a greater number of beam entries in the codebook) compared to the sector-level scanning 400A.

[0093] The number of measurements 402B used in the proposed method 400B is also less than the number of measurements used in the BRP discussed above. Table 2 below compares the number of measurements used for beam selection in RXSS, receive BRP (RX BRP), and the proposed method.

[0094] Table 2

[0095]

[0096] The simulations illustrate the advantages of the proposed method. The parameters and configurations for this numerical evaluation are shown in Table 3 below. Figure 5 The simulation results are shown in .

[0097] Table 3

[0098] #TX Antenna In a uniform linear array (ULA) 256 #RX Antenna {64,256,1024}(ULA) Channel Model 3GPP LOS TX codebook DFT RX codebook DFT SNR -20dB Post-BF SNR 0dB

[0099] Figure 5 Graph 500 shows the probability that a receiving node (eg, UE) detects a beam that maximizes the beamforming gain by acquiring M samples according to some embodiments. R = 64 receive antennas, including NR = 256 receive antennas and includes N R = 1024 receive antennas. CB It is irrelevant and is equal to the number of receiving antennas N CB =N R , the number of measurements for a 90% probability of detection is M ≥ 30. In other words, 30 measurements are sufficient, regardless of the number of receive antennas. This translates into a significant reduction in the number of measurements compared to conventional systems, as summarized in Table 4 below. Table 4 lists the measurement overhead reduction for different numbers of receive antennas and DFT receive codebooks, where the number of codebook entries is equal to the number of receive antennas (N CB =N R ).

[0100] Table 4

[0101] #RX Antenna 64 256 1024 Reduced measurement overhead 60％ 88％ 96％

[0102] The embodiments of the present disclosure may also be used to:

[0103] Detecting whether the wireless channel is in line-of-sight (LOS) or non-line-of-sight (NLOS) state, including detecting whether the receiving node is experiencing a blocking event.

[0104] • Detection of a receive beam that is susceptible to strong interference from another transmitting node.

[0105] A single link of a wireless network with a single transmitting and receiving node is considered. For ease of presentation, we consider a single reception and a single stream transmission, but point out that extension to multiple receiving nodes and / or multi-stream transmission can be achieved by performing the described actions at each receiving node and for each stream. Similarly, if the receiving node is equipped with multiple receiving panels, the described method can be used for each receiving panel. It can be assumed that the initial handshaking has been performed and that the transmitting node has determined a transmit beam that provides reasonable channel gain.

[0106] Embodiments of the present disclosure enable a receiving node to determine the best receive beam based on a potentially large codebook without having to perform measurements on every potential beam. Figure 5 As shown, the number of measurements M that need to be performed can be much smaller than the number of potential receive beams (M << N CB ).

[0107] Figure 6 is a simplified signal flow diagram illustrating signaling for receiving node selection in a wireless communication system 600 according to some embodiments. Assume that the receiving node 604 has N Rantennas, and the transmitting node 602 is equipped with N T For ease of presentation, assume that the baseband channel model, for example, is represented by N for fixed discrete time and frequency. R ×N T The matrix H may give the channel between the transmitting node 602 and the receiving node 604. Let w be the beamforming vector used by the transmitting node to transmit to the receiving node.

[0108] The proposed compressed receive beam management scheme can be divided into the following actions, such as Figure 6 As shown:

[0109] Uniformly sample the receive beam space. Figure 6 As shown, the transmitting node 602 transmits 606 a pilot signal (e.g., a beamformed CSI-RS or PSS / SSS), and the receiving node 604 samples 608 the transmit beam space. Figure 6 Three of these pilot signals are shown as being sent at 606, but there may be more or fewer. By way of non-limiting example, the number M of these samples may be approximately 30, as described above with reference to Figure 5 discussed.

[0110] • If the quality of the samples is sufficient, an acknowledgement (ACK) is signaled 610 from the receiving node 604 to the sending node 602. This operation may be optional.

[0111] • Use the samples to detect 612 the best receive beam from the codebook.

[0112] The sending node 602 sends 614 the data to the receiving node 604 .

[0113] The receiving node 604 receives 616 data from the sending node 602 .

[0114] Reminder: This section is used to describe the Figure 6 Every action.

[0115] RX beamspace sampling

[0116] To enable the receiving node 604 to determine 612 a good receive beam, the transmitting node 602 transmits 606 a sequence of M RS symbols. The i-th measured received signal can be written as y i =a i Hw+n i , where a i is the i-th measurement combination vector. After performing M measurements, the measurement vector is:

[0117] y=AHw+n

[0118] Design measurement combing vector ai This allows each measurement to capture information about a large portion of the receive beam space. In contrast, during the standard RXSS protocol, each measurement only captures information about one beam in the codebook. Figure 7 The differences between these methods are shown.

[0119] Figure 7 is a simplified diagram illustrating the acquisition of information about receive beams 730A and 730B in a system 700A using RXSS and a system 700B according to the proposed method. System 700A includes a transmitting node 702A and a receiving node 704A. When transmitting node 702A transmits a transmit beam 720A including a pilot signal in system 700A using RXSS, information for only a single beam (corresponding to a single codebook element) in receive beams 730A is provided to receiving node 704A. In other words, each measurement captures information for one codebook element.

[0120] System 700B of the proposed method includes a transmitting node 702B and a receiving node 704B. When transmitting node 702B transmits a transmit beam 720B including a pilot signal in system 700B, receiving node 704B receives information from a majority of receive beam space 730B. In other words, each measurement captures information from a majority of the receive beam space.

[0121] ACK signaling

[0122] To determine whether a sufficient number of samples have been collected, each sample is classified as either Class A (useful) or Class B (unuseful). Once a given number of measurements have been collected, an ACK is signaled (e.g., Figure 6 Reference character 610) and trigger the receive beam detection process. The number of required Class A samples can be determined by network configuration or during the warm-up phase. The receiving node can also report / indicate the number of RXSS resources (one resource per RXSS measurement). Therefore, the receiving node implemented according to the embodiments of the present disclosure can require fewer UE RXSS resources than a traditional UE.

[0123] Detecting the best RX beam

[0124] Based on the samples y, the receiving node can estimate different metrics that can be used to determine the best receiving beam. In general, it is possible to estimate the effective channel gain |u H Any index of Hw|, the effective channel gain|u H Hw| is related to the channel H, the transmit beam w, and the potential receive beam u. This can be achieved by defining a function g(y,u) that depends on the sample y and the potential receive beam u. This function is chosen to approximate the effective channel gain |u HHw|≈g(y,u). The optimal receive beam can be found by solving a combinatorial optimization problem:

[0125]

[0126] The beamforming codebook is given by C. The function g(y,u) can be implemented in different ways. It can be given by a linear function of the following form:

[0127] g(y,u)=|u H By|

[0128] where B is N which may depend on the sampling matrix A R ×M matrix.

[0129] Another class of functions can be given by convex optimization algorithms, such as constrained l1 minimization, which is common in compressed sensing applications.

[0130] Machine learning algorithms can also be used to implement the estimation function. In this case, the function can be trained or learned based on a training set. Ultimately, the estimation function will depend on the available context, the computing power of the receiving node, or other constraints.

[0131] Effective interference management

[0132] Consider the downlink of a wireless network with a large number of transmitting and receiving nodes. Assume that the transmitting nodes are connected via a backhaul network that enables fast and reliable sharing of scheduling information, acquired channel state information, and in some embodiments, data sharing. The backhaul network connects all transmitting nodes to a central control node that performs radio resource management (RRM). Make the network dense enough so that each receiving node is within the coverage area of ​​multiple transmitting nodes with a high probability. Also assume that each node is equipped with a large number of antennas (i.e., massive MIMO). In order to fully utilize the potential of dense wireless networks, the transmitting nodes obtain channel state information (CSI) from the receiving nodes within their coverage area. CSI can be used to:

[0133] Radio resource management (beam management, scheduling, link adaptation, etc.)

[0134] Interference management

[0135] Switching from one sending node to another

[0136] Enable multiple connections

[0137] Acquiring CSI (channel state information) in dense wireless systems with a large number of antennas is a challenging problem. First, with a large number of transmit antennas, it is not feasible to use orthogonal resources to measure the channel between any transmit / receive antenna pair. Second, wireless systems operating above 6 GHz may employ a hybrid digital-analog (HDA) transceiver architecture. Using an HDA architecture, it is not possible to measure the signal between any pair of transmit and receive antennas.

[0138] Explicit Feedback

[0139] Conventional systems use explicit feedback of the channel matrix or some function of the channel matrix (e.g., the channel covariance matrix). Pilot signals are broadcast to measure the channel between transmitting and receiving nodes within the coverage area. To avoid interference between transmitting nodes and between transmit antennas of the same transmitting node, pilot signals are sent on orthogonal resources (e.g., different time-frequency resources).

[0140] Feedback of optimal beamforming vectors

[0141] If the beamforming vectors are defined by a codebook, each transmitting node can broadcast a beamforming pilot, allowing each receiving node in the coverage area to determine and feedback a set of preferred beamforming vectors. To avoid interference between transmitting nodes, the pilot signals are sent on orthogonal resources (e.g., different time-frequency resources).

[0142] Another approach to minimize the training and feedback overhead is based on receiving node location information. Yet another approach is based on learning techniques that exploit channel correlations of neighboring TX nodes.

[0143] Explicit feedback and feedback of the preferred beamforming vector use pilot signals sent on orthogonal resources (e.g., different time-frequency resources). The use of orthogonal pilot resources does not scale well with the number of transmitting nodes or the number of transmit antennas. These schemes impose excessive measurement and feedback overhead.

[0144] Position-based methods perform poorly in non-line-of-sight scenarios. Moreover, it is impossible to obtain an accurate estimate of the effective channel gain based on position information.

[0145] Learning-based techniques that exploit the correlation of neighboring transmitting nodes use significant training overhead to achieve the high CSI accuracy required for tasks such as radio resource management or the other tasks outlined above.

[0146] In some embodiments, disclosed herein are systems that use only a small number of coordinated cluster-specific reference signals to be transmitted. In some embodiments, disclosed herein are sampling and signaling schemes that transmit compressed CSI from a receiving node to a transmitting node and a central controller. In some embodiments, efficient decompression schemes estimate relevant system parameters (e.g., effective channel gain, SINR, strongest interferer, etc.) based on compressed CSI measurements. Advantages of these methods include:

[0147] Since all transmitting nodes use the same spectrum resources to sense the channel simultaneously, the measurement overhead is significantly reduced.

[0148] • The sensing scheme is non-adaptive (cell / cluster specific), in the sense that the measurement signal can be used by all receiving nodes simultaneously.

[0149] RRM has similar flexibility to the latest explicit feedback schemes. RRM has all the degrees of freedom to select transmission parameters, such as scheduled RX nodes, beamforming vectors, modulation and coding schemes, etc.

[0150] Figure 8 8 is a simplified diagram of a wireless network 800 according to some embodiments. In the downlink of the wireless network 800, the wireless network 800 may include a number B of transmitting nodes 802 (e.g., base stations) and a number U of receiving nodes 804 (e.g., user equipment). Each transmitting node 804 is equipped with a number N of B antennas, and each receiving node 804 is equipped with N U receiving antenna.

[0151] Transmitting nodes 802 may be communicatively coupled to a central control node 806 via a high-capacity and low-latency backhaul network 808. Each of transmitting nodes 802 and central control node 806 may include a coverage area 810. Central control node 806 performs radio resource management (RRM). It is assumed that network 800 is sufficiently dense that each receiving node 804 is within the coverage area 810 of multiple transmitting nodes 802 with a high probability. It is assumed that transmitting nodes 802 are grouped in coordination clusters, and for ease of presentation, a single coordination cluster is considered. All transmitting nodes in the coordination cluster are synchronized at the symbol level.

[0152] Figure 99 is a simplified illustration of a frame structure 900 according to some embodiments. Frame 900 is divided into subframes 910; subframes 910 are divided into multiple time slots 920; and a time slot includes multiple symbols 930 (e.g., OFDM or single carrier symbols). Within frame 900, certain time slots 920 are reserved for transmission of CSI-RS. The location of CSI-RS time slots 920 is important to all transmitting nodes 802 and receiving nodes 804 ( Figure 8 ) are all known.

[0153] Reference again Figure 8 , assuming that when the receiving node 804 has successfully performed the initial access procedure, the receiving node 804 is attached to the network 800 and connected to the RRM. The following discussion will discuss the measurement phase, the feedback phase, and the scheduling and data transmission phase. These phases will be combined Figure 10 discuss.

[0154] Figure 10 is a simplified signal flow diagram illustrating a CSI acquisition scheme 1000 according to some embodiments.

[0155] Measurement phase

[0156] refer to Figure 8 and Figure 10 In a given CSI-RS slot i, the transmitting node 802 simultaneously transmits (1010)M precoded RS signals to the receiving node 804 The sequence of (sending node b), i=1,…,M. The i-th RS signal received (1020) by receiving node u 804 can be written as:

[0157]

[0158] Its receive filter (assumed to be fixed a priori), the channel matrix and additive noise Defining the composite channel matrix And composite precoded RS:

[0159]

[0160] The received signal can be written as:

[0161]

[0162] Receive M precoded Afterwards, the measurement vector collected by the receiving node u is:

[0163]

[0164] Compared to conventional CSI acquisition schemes, the measurement protocol does not use orthogonal pilots. In fact, embodiments of the present disclosure include non-orthogonal RSs. Non-orthogonal RSs enable each receiving node 804 (e.g., u) to measure (1020) the effective composite channel M projections of Under certain conditions, the measurement overhead M is significantly smaller than that of traditional channel acquisition schemes.

[0165] Feedback Phase

[0166] Continue to refer Figure 8 and 10 , receiving node u 804 from vector y u The feedback message from receiving node u 804 may be made available to the central control node 806. The feedback message may be sent by z i =f(y u )+q i Given, where the function f(y) selects a particular measurement, and q i is the additional quantization noise. The function f(y) can select y above a certain threshold ε i Elements of (e.g., |z i |>ε).

[0167] The described feedback protocol differs from conventional feedback schemes in that conventional schemes use measurements to estimate the channel or some representation of the channel before generating the feedback message.Thus, the embodiments disclosed herein enable UEs (receiving nodes 804) with less computational power to be employed.

[0168] Scheduling and data transmission phase

[0169] Based on the feedback messages from the plurality of receiving nodes 804, the central control node 806 is enabled to estimate (1060) various scheduling metrics. In general, the effective channel gain can be estimated to depend on Any indicator, the effective channel gain and Channel is related to the beamforming vector w∈C, an element of the beamforming codebook. This can be achieved by defining a quantized measure z u and the beamforming vector w function Ψ(z u ,w) to achieve this, this function approximates the effective channel gain Examples of scheduling metrics include SINR:

[0170]

[0171] Assume that w i is the beamforming vector assigned to the receiving node i, 804, and w j is the beamforming vector assigned to an interfering UE (e.g., receiving node 804) scheduled on the same resource element. Another example could be the leakage interference power ∑ j≠u Ψ(z u ,w u ) 2 , which can be used for interference management.

[0172] Estimation function Ψ(z u ,w j ) can be implemented in a variety of ways. The final choice of Ψ(·,·) depends on the structure of the composite channel matrix (i.e., low rank, sparsity, etc.), the required estimation accuracy, the computational power of the central controller, or other system constraints (e.g., latency). The estimation function can be given by a linear function of the following form:

[0173]

[0174] where Ψ is the BN that may depend on the measurement matrix Φ B ×M matrix.

[0175] Another class of functions can be given by convex optimization algorithms, such as constrained l1 minimization, which is common in compressed sensing applications. Machine learning algorithms can also be used to implement the estimation function. In this case, the estimation function can be trained or learned based on a training set.

[0176] Figure 11 The architecture of a system 1100 of a network according to some embodiments is shown. System 1100 is shown as including user equipment (UE) 1101 and UE 1102. UEs 1101 and 1102 are shown as smartphones (e.g., handheld touchscreen mobile computing devices that can connect to one or more cellular networks), but may include any mobile or non-mobile computing device, such as a personal data assistant (PDA), a pager, a laptop computer, a desktop computer, a wireless handheld device, or any computing device that includes a wireless communication interface.

[0177] In some embodiments, any of UEs 1101 and 1102 may include an Internet of Things (IoT) UE, which may include a network access layer designed for low-power IoT applications that utilize short-term UE connections. The IoT UE may utilize technologies such as machine-to-machine (M2M) or machine-type communication (MTC) to exchange data with an MTC server or device via a public land mobile network (PLMN), proximity services (ProSe) or device-to-device (D2D) communication, a sensor network, or an IoT network. The M2M or MTC data exchange may be a machine-initiated data exchange. The IoT network describes interconnected IoT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure) with short-term connections. The IoT UE may execute background applications (e.g., keep-alive messages, status updates, etc.) to facilitate connectivity to the IoT network.

[0178] UEs 1101 and 1102 may be configured to connect (e.g., be communicatively coupled) to a radio access network (RAN) 1110, which may be, for example, an evolved universal mobile telecommunications system (UMTS) terrestrial radio access network (E-UTRAN), a NextGen RAN (NG RAN), or other types of RANs. UEs 1101 and 1102 utilize connections 1103 and 1104, respectively, each of which includes a physical communication interface or layer (discussed in further detail below). In this example, connections 1103 and 1104 are shown as air interfaces for achieving communicative coupling and may conform to cellular communication protocols, such as a global system for mobile communications (GSM) protocol, a code division multiple access (CDMA) network protocol, a push-to-talk (PTT) protocol, a PTT over cellular (POC) protocol, a universal mobile telecommunications system (UMTS) protocol, a 3GPP long term evolution (LTE) protocol, a fifth generation (5G) protocol, a new radio (NR) protocol, and the like.

[0179] In this embodiment, the UEs 1101 and 1102 may also directly exchange communication data via the ProSe interface 1105. The ProSe interface 1105 may alternatively be referred to as a sidelink interface, which includes one or more logical channels, including but not limited to a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), a physical sidelink discovery channel (PSDCH), and a physical sidelink broadcast channel (PSBCH).

[0180] UE 1102 is shown as being configured to access access point (AP) 1106 via connection 1107. Connection 1107 may include a local wireless connection, such as one compliant with any IEEE 802.11 protocol, where AP 1106 would include Wi-Fi. In this example, AP 1106 is shown connected to the Internet and not to the core network of the wireless system (described in further detail below).

[0181] The RAN 1110 may include one or more access nodes that enable connections 1103 and 1104. These access nodes (ANs) may be referred to as base stations (BSs), NodeBs, evolved NodeBs (eNBs), next-generation NodeBs (gNBs), RAN nodes, etc., and may include ground stations (e.g., terrestrial access points) or satellite stations that provide coverage within a geographic area (e.g., a cell). The RAN 1110 may include one or more RAN nodes (e.g., macro RAN nodes 1111) for providing macro cells and one or more RAN nodes (e.g., low power (LP) RAN nodes 1112) for providing femto cells or pico cells (e.g., cells with smaller coverage areas, smaller user capacity, or higher bandwidth than macro cells).

[0182] Either of the RAN nodes 1111 and 1112 may terminate the air interface protocol and may be the first point of contact for the UEs 1101 and 1102. In some embodiments, either of the RAN nodes 1111 and 1112 may perform various logical functions of the RAN 1110, including but not limited to radio network controller (RNC) functions, such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management.

[0183] According to some embodiments, UEs 1101 and 1102 may be configured to communicate with each other or with any of RAN nodes 1111 and 1112 using orthogonal frequency division multiplexing (OFDM) communication signals over multi-carrier communication channels in accordance with various communication techniques, such as, but not limited to, orthogonal frequency division multiple access (OFDMA) communication techniques (e.g., for downlink communication) or single-carrier frequency division multiple access (SC-FDMA) communication techniques (e.g., for uplink and ProSe or sidelink communication), although the scope of the embodiments is not limited in this regard. The OFDM signal may include multiple orthogonal subcarriers.

[0184] In some embodiments, a downlink resource grid can be used for downlink transmissions from either RAN nodes 1111 and 1112 to UEs 1101 and 1102, while uplink transmissions can utilize similar techniques. The grid can be a time-frequency grid, referred to as a resource grid or time-frequency resource grid, representing the physical resources in each time slot in the downlink. This time-frequency plane representation is common in OFDM systems, making radio resource allocation intuitive. Each column and row of the resource grid corresponds to an OFDM symbol and an OFDM subcarrier, respectively. The duration of the resource grid in the time domain corresponds to a time slot in a radio frame. The smallest time-frequency unit in the resource grid is called a resource element. Each resource grid includes multiple resource blocks, which describe the mapping of certain physical channels to resource elements. Each resource block includes a collection of resource elements; in the frequency domain, this can represent the minimum amount of resources that can currently be allocated. There are several different physical downlink channels that are transmitted using such resource blocks.

[0185] The physical downlink shared channel (PDSCH) can carry user data and higher-layer signaling to UEs 1101 and 1102. The physical downlink control channel (PDCCH) can carry information about, among other things, the transport format and resource allocation associated with the PDSCH channel. It can also inform UEs 1101 and 1102 of the transport format, resource allocation, and H-ARQ (Hybrid Automatic Repeat Request) information associated with the uplink shared channel. Typically, downlink scheduling (allocation of control channel resource blocks and shared channel resource blocks to UEs 1101 and 1102 within a cell) can be performed at either RAN node 1111 or 1112 based on channel quality information fed back from either UE 1101 or 1102. Downlink resource allocation information can be sent on the PDCCH for (e.g., allocated to) each of UEs 1101 and 1102.

[0186] PDCCH can use control channel elements (CCE) to convey control information. Before being mapped to resource elements, PDCCH complex symbols can first be organized into four tuples, which can then be arranged using a sub-block interleaver for rate matching. One or more of these CCEs can be used to send each PDCCH, where each CCE can correspond to nine groups of four physical resource elements called resource element groups (REGs). Four orthogonal phase shift keying (QPSK) symbols can be mapped to each REG. PDCCH can be sent using one or more CCEs, depending on the size of the downlink control information (DCI) and the channel conditions. Four or more different PDCCH formats with different numbers of CCEs (e.g., aggregation levels, L=1, 2, 4, or 8) can be defined in LTE.

[0187] Some embodiments may use a concept that is an extension of the above concept to allocate resources for control channel information. For example, some embodiments may utilize an enhanced physical downlink control channel (EPDCCH), which uses PDSCH resources for control information transmission. EPDCCH may be transmitted using one or more enhanced control channel elements (ECCEs). Similar to the above, each ECCE may correspond to nine groups of four physical resource elements called enhanced resource element groups (EREGs). In some cases, an ECCE may have other numbers of EREGs.

[0188] RAN 1110 is shown as being communicatively coupled to a core network (CN) 1120 via an S1 interface 1113. In an embodiment, CN 1120 may be an Evolved Packet Core (EPC) network, a Next Generation Packet Core (NPC) network, or some other type of CN. In this embodiment, S1 interface 1113 is divided into two parts: an S1-U interface 1114, which carries traffic data between RAN nodes 1111 and 1112 and a Serving Gateway (S-GW) 1122; and an S1 Mobility Management Entity (MME) interface 1115, which is a signaling interface between RAN nodes 1111 and 1112 and MME 1121.

[0189] In this embodiment, CN 1120 includes MME 1121, S-GW 1122, Packet Data Network (PDN) Gateway (P-GW) 1123, and Home Subscriber Server (HSS) 1124. MME 1121 can be functionally similar to the control plane of a legacy Serving General Packet Radio Service (GPRS) Support Node (SGSN). MME 1121 can manage mobility aspects of access, such as gateway selection and tracking area list management. HSS 1124 can include a database for network users, including subscription-related information used to support network entities in handling communication sessions. CN 1120 can include one or more HSSs 1124, depending on the number of mobile subscribers, device capacity, network organization, etc. For example, HSS 1124 can provide support for routing / roaming, authentication, authorization, naming / addressing solutions, location dependencies, etc.

[0190] The S-GW 1122 may terminate the S1 interface 1113 to the RAN 1110 and route data packets between the RAN 1110 and the CN 1120. Furthermore, the S-GW 1122 may be the local mobility anchor for inter-RAN node handovers and may also provide an anchor for inter-3GPP mobility. Other responsibilities may include legal interception, charging, and certain policy enforcement.

[0191] The P-GW 1123 may terminate the SGi interface to the PDN. The P-GW 1123 may route data packets between the CN 1120 (e.g., the EPC network) and an external network (e.g., a network including an application server 1130 (alternatively referred to as an application function (AF))) via an Internet Protocol (IP) interface 1125. The application server 1130 may be an element that provides applications (e.g., UMTS packet service (PS) domain, LTE PS data service, etc.) that use IP bearer resources to the core network. In this embodiment, the P-GW 1123 is shown as being communicatively coupled to the application server 1130 via the IP communication interface 1125. The application server 1130 may also be configured to support one or more communication services (e.g., voice over Internet Protocol (VoIP) sessions, PTT sessions, group communication sessions, social networking services, etc.) for the UEs 1101 and 1102 via the CN 1120.

[0192] P-GW 1123 can also be a node for policy enforcement and charging data collection. Policy and Charging Rules Function (PCRF) 1126 is the policy and charging control element of CN 1120. In a non-roaming scenario, a single PCRF may be associated with the UE's Internet Protocol Connectivity Access Network (IP-CAN) session in the Home Public Land Mobile Network (HPLMN). In a roaming scenario where service is not local, two PCRFs may be associated with the UE's IP-CAN session: the Home PCRF (H-PCRF) in the HPLMN and the Visited PCRF (V-PCRF) in the Visited Public Land Mobile Network (VPLMN). PCRF 1126 may be communicatively coupled to application server 1130 via P-GW 1123. Application server 1130 may signal PCRF 1126 to indicate a new service flow and select appropriate quality of service (QoS) and charging parameters. PCRF 1126 may provide the rules to a Policy and Charging Enforcement Function (PCEF) (not shown) with the appropriate Traffic Flow Template (TFT) and QoS Class Identifier (QCI), which initiates QoS and charging as specified by the Application Server 1130 .

[0193] Figure 12Example components of a device 1200 according to some embodiments are shown. In some embodiments, the device 1200 may include application circuitry 1202, baseband circuitry 1204, radio frequency (RF) circuitry 1206, front-end module (FEM) circuitry 1208, one or more antennas 1210, and power management circuitry (PMC) 1212, coupled together at least as shown. The components of the device 1200 shown may be included in a UE or a RAN node. In some embodiments, the device 1200 may include fewer elements (e.g., a RAN node may not utilize application circuitry 1202 and instead include a processor / controller to process IP data received from an EPC). In some embodiments, the device 1200 may include additional elements, such as memory / storage, a display, a camera, sensors, or input / output (I / O) interfaces. In other embodiments, the components described below may be included in more than one device (e.g., for a cloud RAN (C-RAN) implementation, the circuitry may be individually included in more than one device).

[0194] The application circuitry 1202 may include one or more application processors. For example, the application circuitry 1202 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processors may include any combination of general-purpose processors and specialized processors (e.g., graphics processors, application processors, etc.). The processors may be coupled to or include memory / storage and may be configured to execute instructions stored in the memory / storage to enable various applications or operating systems to run on the device 1200. In some embodiments, the processors of the application circuitry 1202 may process IP data packets received from the EPC.

[0195] The baseband circuitry 1204 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The baseband circuitry 1204 may include one or more baseband processors or control logic to process baseband signals received from the receive signal path of the RF circuitry 1206 and generate baseband signals for the transmit signal path of the RF circuitry 1206. The baseband circuitry 1204 may interface with the application circuitry 1202 to generate and process baseband signals and control the operation of the RF circuitry 1206. For example, in some embodiments, the baseband circuitry 1204 may include a third-generation (3G) baseband processor 1204A, a fourth-generation (4G) baseband processor 1204B, a fifth-generation (5G) baseband processor 1204C, or other baseband processors 1204D for other existing, developing, or future generations (e.g., second-generation (2G), sixth-generation (6G), etc.). Baseband circuitry 1204 (e.g., one or more of baseband processors 1204A-D) may handle various radio control functions that enable communication with one or more radio networks via RF circuitry 1206. In other embodiments, some or all of the functions of baseband processors 1204A-D may be included in modules stored in memory 1204G and executed by central processing unit (CPU) 1204E. Radio control functions may include, but are not limited to, signal modulation / demodulation, encoding / decoding, radio frequency shifting, and the like. In some embodiments, the modulation / demodulation circuitry of baseband circuitry 1204 may include fast Fourier transform (FFT), precoding, or constellation mapping / demapping functions. In some embodiments, the encoding / decoding circuitry of baseband circuitry 1204 may include convolution, tail-biting, turbo, Viterbi, or low-density parity check (LDPC) encoder / decoder functions. Embodiments of the modulation / demodulation and encoder / decoder functions are not limited to these examples and may include other suitable functions in other embodiments.

[0196] In some embodiments, baseband circuitry 1204 may include one or more audio digital signal processors (DSPs) 1204F. Audio DSPs 1204F may include components for compression / decompression and echo cancellation, and in other embodiments may include other suitable processing elements. In some embodiments, the components of the baseband circuitry may be suitably combined in a single chip, a single chipset, or provided on the same circuit board. In some embodiments, some or all of the components of baseband circuitry 1204 and application circuitry 1202 may be implemented together, for example, on a system on a chip (SOC).

[0197] In some embodiments, baseband circuitry 1204 can provide communications compatible with one or more radio technologies. For example, in some embodiments, baseband circuitry 1204 can support communications with an Evolved Universal Terrestrial Radio Access Network (EUTRAN) or other wireless metropolitan area network (WMAN), wireless local area network (WLAN), or wireless personal area network (WPAN). Embodiments in which baseband circuitry 1204 is configured to support radio communications of more than one wireless protocol may be referred to as multi-mode baseband circuitry.

[0198] RF circuitry 1206 can utilize modulated electromagnetic radiation via a non-solid medium to facilitate communication with a wireless network. In various embodiments, RF circuitry 1206 can include switches, filters, amplifiers, and the like to facilitate communication with the wireless network. RF circuitry 1206 can include a receive signal path, which can include circuitry for downconverting RF signals received from FEM circuitry 1208 and providing baseband signals to baseband circuitry 1204. RF circuitry 1206 can also include a transmit signal path, which can include circuitry for upconverting baseband signals provided by baseband circuitry 1204 and providing an RF output signal to FEM circuitry 1208 for transmission.

[0199] In some embodiments, the receive signal path of RF circuitry 1206 may include mixer circuitry 1206A, amplifier circuitry 1206B, and filter circuitry 1206C. In some embodiments, the transmit signal path of RF circuitry 1206 may include filter circuitry 1206C and mixer circuitry 1206A. RF circuitry 1206 may also include synthesizer circuitry 1206D for synthesizing frequencies used by mixer circuitry 1206A in the receive and transmit signal paths. In some embodiments, mixer circuitry 1206A in the receive signal path may be configured to downconvert the RF signal received from FEM circuitry 1208 based on the synthesized frequency provided by synthesizer circuitry 1206D. Amplifier circuitry 1206B may be configured to amplify the downconverted signal, and filter circuitry 1206C may be a low-pass filter (LPF) or a band-pass filter (BPF) configured to remove unwanted signals from the downconverted signal to generate an output baseband signal. The output baseband signal may be provided to baseband circuitry 1204 for further processing. In some embodiments, the output baseband signal may be a zero-frequency baseband signal, but this is not a requirement.In some embodiments, the mixer circuit 1206A of the receive signal path may include a passive mixer, but the scope of the embodiments is not limited in this regard.

[0200] In some embodiments, mixer circuit 1206A of the transmit signal path can be configured to upconvert an input baseband signal based on a synthesized frequency provided by synthesizer circuit 1206D to generate an RF output signal for FEM circuit 1208. The baseband signal can be provided by baseband circuit 1204 and filtered by filter circuit 1206C.

[0201] In some embodiments, the mixer circuit 1206A of the receive signal path and the mixer circuit 1206A of the transmit signal path may include two or more mixers and may be arranged for quadrature down-conversion and up-conversion, respectively. In some embodiments, the mixer circuit 1206A of the receive signal path and the mixer circuit 1206A of the transmit signal path may include two or more mixers and may be arranged for image rejection (e.g., Hartley image rejection). In some embodiments, the mixer circuit 1206A of the receive signal path and the mixer circuit 1206A of the transmit signal path may be arranged for direct down-conversion and direct up-conversion, respectively. In some embodiments, the mixer circuit 1206A of the receive signal path and the mixer circuit 1206A of the transmit signal path may be configured for superheterodyne operation.

[0202] In some embodiments, the output baseband signal and the input baseband signal may be analog baseband signals, but the scope of the embodiments is not limited in this regard. In some alternative embodiments, the output baseband signal and the input baseband signal may be digital baseband signals. In these alternative embodiments, RF circuitry 1206 may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry, and baseband circuitry 1204 may include a digital baseband interface to communicate with RF circuitry 1206.

[0203] In some dual-mode embodiments, separate radio IC circuits may be provided for processing signals for each spectrum, although the scope of the embodiments is not limited in this regard.

[0204] In some embodiments, synthesizer circuit 1206D may be a fractional-N synthesizer or a fractional-N / N+1 synthesizer, but the scope of the embodiments is not limited in this regard, as other types of frequency synthesizers may be suitable. For example, synthesizer circuit 1206D may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer including a phase-locked loop with a frequency divider.

[0205] Synthesizer circuit 1206D may be configured to synthesize an output frequency based on the frequency input and the divider control input for use by mixer circuit 1206A of RF circuit 1206. In some embodiments, synthesizer circuit 1206D may be a fractional-N / N+1 synthesizer.

[0206] In some embodiments, the frequency input can be provided by a voltage-controlled oscillator (VCO), but this is not required. The divider control input can be provided by baseband circuitry 1204 or application processor 1202, depending on the desired output frequency. In some embodiments, the divider control input (e.g., N) can be determined from a lookup table based on the channel indicated by application processor 1202.

[0207] The synthesizer circuit 1206D of the RF circuit 1206 may include a divider, a delay-locked loop (DLL), a multiplexer, and a phase accumulator. In some embodiments, the divider may be a dual-mode divider (DMD), and the phase accumulator may be a digital phase accumulator (DPA). In some embodiments, the DMD may be configured to divide the input signal by N or N+1 (e.g., based on a carry) to provide a fractional division ratio. In some example embodiments, the DLL may include a set of cascaded tunable delay elements, a phase detector, a charge pump, and a D flip-flop. In these embodiments, the delay elements may be configured to decompose the VCO cycle into Nd equal phase groups, where Nd is the number of delay elements in the delay line. In this way, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle.

[0208] In some embodiments, synthesizer circuit 1206D can be configured to generate a carrier frequency as an output frequency, while in other embodiments, the output frequency can be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency) and used in conjunction with a quadrature generator and divider circuit to generate multiple signals at the carrier frequency with multiple different phases relative to each other. In some embodiments, the output frequency can be an LO frequency (fLO). In some embodiments, RF circuit 1206 can include an IQ / polar converter.

[0209] The FEM circuitry 1208 may include a receive signal path, which may include circuitry configured to operate on RF signals received from one or more antennas 1210, amplify the received signals, and provide an amplified version of the received signals to the RF circuitry 1206 for further processing. The FEM circuitry 1208 may also include a transmit signal path, which may include circuitry configured to amplify signals provided by the RF circuitry 1206 for transmission by one or more of the one or more antennas 1210. In various embodiments, amplification by the transmit signal path or the receive signal path may be performed solely in the RF circuitry 1206, solely in the FEM 1208, or in both the RF circuitry 1206 and the FEM 1208.

[0210] In some embodiments, the FEM circuitry 1208 may include a TX / RX switch to switch between transmit and receive modes of operation. The FEM circuitry 1208 may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry 1208 may include an LNA to amplify a received RF signal and provide the amplified received RF signal as an output (e.g., to the RF circuitry 1206). The transmit signal path of the FEM circuitry 1208 may include a power amplifier (PA) to amplify an input RF signal (e.g., provided by the RF circuitry 1206) and one or more filters to generate an RF signal for subsequent transmission (e.g., by one or more of the one or more antennas 1210).

[0211] In some embodiments, PMC 1212 can manage the power provided to baseband circuitry 1204. Specifically, PMC 1212 can control power source selection, voltage scaling, battery charging, or DC-DC conversion. PMC 1212 is typically included when device 1200 is capable of being powered by a battery, such as when the device is included in a UE. PMC 1212 can improve power conversion efficiency while providing a desired implementation size and heat dissipation characteristics.

[0212] Although Figure 12 The PMC 1212 is shown coupled only to the baseband circuit 1204, but in other embodiments, the PMC 1212 may additionally or alternatively be coupled to other components and perform similar power management operations for the other components, such as, but not limited to, the application circuit 1202, the RF circuit 1206, or the FEM 1208.

[0213] In some embodiments, the PMC 1212 may control, or be part of, various power saving mechanisms of the device 1200. For example, if the device 1200 is in the RRC_Connected state (wherein it remains connected to the RAN node because it expects to receive traffic in the near future), it may enter a state known as discontinuous reception mode (DRX) after a period of inactivity. During this state, the device 1200 may be powered down for brief intervals, thereby saving power.

[0214] If there is no data traffic activity for an extended period of time, the device 1200 may transition to the RRC_Idle state (where it is disconnected from the network and does not perform operations such as channel quality feedback, handovers, etc.). The device 1200 enters a very low-power state and performs paging, where it periodically wakes up again to listen to the network and then powers down again. The device 1200 cannot receive data in this state and must transition back to the RRC_Connected state in order to receive data.

[0215] An additional power saving mode can allow a device to be unavailable to the network for a period longer than the paging interval (ranging from a few seconds to a few hours). During this time, the device is completely unavailable to the network and can be completely powered off. Any data sent during this time will incur a significant delay, assuming this delay is acceptable.

[0216] The processor of the application circuitry 1202 and the processor of the baseband circuitry 1204 can be used to execute elements of one or more instances of a protocol stack. For example, the processor of the baseband circuitry 1204 (alone or in combination) can be used to perform layer 3, layer 2, or layer 1 functions, while the processor of the application circuitry 1202 can utilize data received from these layers (e.g., packet data) and further perform layer 4 functions (e.g., transport communication protocol (TCP) and user datagram protocol (UDP) layers). As mentioned herein, layer 3 may include a radio resource control (RRC) layer, which is described in further detail below. As mentioned herein, layer 2 may include a medium access control (MAC) layer, a radio link control (RLC) layer, and a packet data convergence protocol (PDCP) layer, which are described in further detail below. As mentioned herein, layer 1 may include a physical (PHY) layer of a UE / RAN node, which is described in further detail below.

[0217] Figure 13 1 shows an example interface of a baseband circuit according to some embodiments. As discussed above, Figure 12 The baseband circuit 1204 may include processors 1204A-1204E and a memory 1204G used by the processors. Each of the processors 1204A-1204E may include a memory interface 1304A-1304E, respectively, to send / receive data to / from the memory 1204G.

[0218] The baseband circuit 1204 may also include one or more interfaces for communicatively coupling to other circuits / devices, such as a memory interface 1312 (e.g., an interface for sending / receiving data to / from a memory external to the baseband circuit 1204), an application circuit interface 1314 (e.g., an interface for sending / receiving data to / from a memory external to the baseband circuit 1204), and an application circuit interface 1315 (e.g., an interface for sending / receiving data to / from a memory external to the baseband circuit 1204). Figure 12 an interface for sending / receiving data to / from the application circuit 1202), an RF circuit interface 1316 (for example, an interface for sending / receiving data to / from the application circuit 1202), and an RF circuit interface 1316 (for example, an interface for sending / receiving data to / from the application circuit 1202). Figure 12 an interface for sending / receiving data to / from a RF circuit 1206), a wireless hardware connection interface 1318 (e.g., for sending / receiving data to / from a near field communication (NFC) component, Components (e.g., low power ), components and other communication components to send / receive data) and a power management interface 1320 (for example, an interface for sending / receiving power or control signals to / from the PMC 1212).

[0219] Figure 14 is a diagram of a control plane protocol stack according to some embodiments. In this embodiment, the control plane 1400 is shown as a communication protocol stack between UE 1101 (or alternatively, UE 1102), RAN node 1111 (or alternatively, RAN node 1112) and MME 1121.

[0220] The PHY layer 1401 may send or receive information over one or more air interfaces for use by the MAC layer 1402. The PHY layer 1401 may also perform link adaptation or adaptive modulation and coding (AMC), power control, cell search (e.g., for initial synchronization and handover purposes), and other measurements used by higher layers such as the RRC layer 1405. The PHY layer 1401 may still further perform error detection on transport channels, forward error correction (FEC) encoding / decoding of transport channels, modulation / demodulation of physical channels, interleaving, rate matching, mapping to physical channels, and multiple-input multiple-output (MIMO) antenna processing.

[0221] The MAC layer 1402 can perform mapping between logical channels and transport channels, multiplexing MAC service data units (SDUs) from one or more logical channels into transport blocks (TBs) for delivery to the PHY via the transport channels, demultiplexing MAC SDUs from transport blocks (TBs) delivered from the PHY via the transport channels to one or more logical channels, multiplexing MAC SDUs into TBs, scheduling information reporting, error correction through hybrid automatic repeat request (HARQ), and logical channel priority sorting.

[0222] The RLC layer 1403 can operate in multiple modes of operation, including transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). The RLC layer 1403 can perform transmission of upper layer protocol data units (PDUs), error correction through automatic repeat request (ARQ) for AM data transmission, and concatenation, segmentation, and reassembly of RLC SDUs for UM and AM data transmission. The RLC layer 1403 can also perform re-segmentation of RLC data PDUs for AM data transmission, reorder RLC data PDUs for UM and AM data transmission, detect duplicate data for UM and AM data transmission, discard RLC SDUs for UM and AM data transmission, detect protocol errors for AM data transmission, and perform RLC re-establishment.

[0223] The PDCP layer 1404 can perform header compression and decompression of IP data, maintain the PDCP sequence number (SN), perform in-sequence delivery of upper layer PDUs when reestablishing lower layers, eliminate duplication of lower layer SDUs for radio bearers mapped on RLC AM when reestablishing lower layers, encrypt and decrypt control plane data, perform integrity protection and integrity verification of control plane data, control timer-based data discard, and perform security operations (e.g., encryption, decryption, integrity protection, integrity verification, etc.).

[0224] The main services and functions of the RRC layer 1405 may include broadcasting of system information (e.g., included in a master information block (MIB) or system information block (SIB) related to the non-access stratum (NAS)), broadcasting of system information related to the access stratum (AS), paging, establishment, maintenance, and release of the RRC connection between the UE and the E-UTRAN (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), establishment, configuration, maintenance, and release of point-to-point radio bearers, security functions (including key management), inter-radio access technology (RAT) mobility, and measurement configuration for UE measurement reporting. The MIB and SIB may include one or more information elements (IEs), each of which may include a separate data field or data structure.

[0225] UE 1101 and RAN node 1111 may utilize a Uu interface (eg, LTE-Uu interface) to exchange control plane data via a protocol stack (including a PHY layer 1401 , a MAC layer 1402 , an RLC layer 1403 , a PDCP layer 1404 , and an RRC layer 1405 ).

[0226] In the illustrated embodiment, non-access stratum (NAS) protocols 1406 form the highest layer of the control plane between UE 1101 and MME 1121. NAS protocols 1406 support UE 1101 mobility and session management procedures to establish and maintain IP connectivity between UE 1101 and P-GW 1123.

[0227] The S1 Application Protocol (S1-AP) layer 1415 can support the functionality of the S1 interface and includes Elementary Procedures (EPs). EPs are the unit of interaction between the RAN node 1111 and the CN 1120. S1-AP layer services can include two groups: UE-associated services and non-UE-associated services. These services perform functions including, but not limited to, E-UTRAN Radio Access Bearer (E-RAB) management, UE capability indication, mobility, NAS signaling, RAN Information Management (RIM), and configuration transfer.

[0228] The Stream Control Transmission Protocol (SCTP) layer (alternatively referred to as the Stream Control Transmission Protocol / Internet Protocol (SCTP / IP) layer) 1414 can ensure reliable delivery of signaling messages between the RAN node 1111 and the MME 1121 based in part on the IP protocol supported by the IP layer 1413. The L2 layer 1412 and the L1 layer 1411 can refer to communication links (e.g., wired or wireless) used by the RAN node and the MME to exchange information.

[0229] The RAN node 1111 and the MME 1121 may exchange control plane data via a protocol stack using an S1-MME interface, including an L1 layer 1411 , an L2 layer 1412 , an IP layer 1413 , an SCTP layer 1414 , and an S1-AP layer 1415 .

[0230] Figure 15 Components of a core network according to some embodiments are shown. The components of CN 1120 can be implemented in one physical node, or in separate physical nodes, including components for reading and executing instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium). In some embodiments, network function virtualization (NFV) is used to virtualize any or all of the above-described network node functions (described in further detail below) via executable instructions stored in one or more computer-readable storage media. A logical instantiation of CN 1120 can be referred to as a network slice 1501. A logical instantiation of a portion of CN 1120 can be referred to as a network sub-slice 1502 (e.g., network sub-slice 1502 is shown as including PGW 1123 and PCRF 1126).

[0231] NFV architecture and infrastructure can be used to virtualize one or more network functions (otherwise performed by dedicated hardware) onto physical resources including a combination of industry-standard server hardware, storage hardware, or switches. In other words, the NFV system can be used to perform a virtual or reconfigurable implementation of one or more EPC components / functions.

[0232] Figure 16 is a block diagram illustrating components capable of reading instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium) and executing any one or more of the methods discussed herein, according to some example embodiments. Specifically, Figure 16A graphical representation of hardware resources 1600 is shown, including one or more processors (or processor cores) 1610, one or more memory / storage devices 1620, and one or more communication resources 1630, each of which may be communicatively coupled via a bus 1640. For embodiments utilizing node virtualization (e.g., NFV), a hypervisor 1602 may be executed to provide an execution environment for one or more network slices / subslices to utilize the hardware resources 1600.

[0233] Processor 1610 (e.g., a central processing unit (CPU), a reduced instruction set computing (RISC) processor, a complex instruction set computing (CISC) processor, a graphics processing unit (GPU), a digital signal processor (DSP), such as a baseband processor, an application-specific integrated circuit (ASIC), a radio frequency integrated circuit (RFIC), another processor, or any suitable combination thereof) may include, for example, processor 1612 and processor 1614.

[0234] The memory / storage device 1620 may include main memory, disk storage, or any suitable combination thereof. The memory / storage device 1620 may include, but is not limited to, any type of volatile or non-volatile memory, such as dynamic random access memory (DRAM), static random access memory (SRAM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, solid-state storage, etc.

[0235] The communication resources 1630 may include interconnect or network interface components or other suitable devices to communicate with one or more peripheral devices 1604 or one or more databases 1606 via the network 1608. For example, the communication resources 1630 may include a wired communication component (e.g., for coupling via a universal serial bus (USB)), a cellular communication component, an NFC component, Components (e.g., low power ), components and other communication components.

[0236] The instructions 1650 may include software, a program, an application, an applet, an app, or other executable code for causing at least any processor 1610 to perform any one or more of the methods discussed herein. The instructions 1650 may reside, in whole or in part, within at least one of the processor 1610 (e.g., within a cache of the processor), the memory / storage device 1620, or any suitable combination thereof. In addition, any portion of the instructions 1650 may be transferred to the hardware resources 1600 from any combination of the peripheral device 1604 or the database 1606. Thus, the memory of the processor 1610, the memory / storage device 1620, the peripheral device 1604, and the database 1606 are examples of computer-readable and machine-readable media.

[0237] Figure 17 is a simplified flow chart illustrating a method 1700 of operating a wireless communication node (e.g., a receiving node) according to some embodiments. Figures 12 to 16 equipment, especially Figure 13 The baseband circuitry of the device may be configured to identify 1710 or cause identification of a channel state information reference signal (CSI-RS) received from a transmit / receive point (TRP). The device may be further configured to determine 1720 or cause determination of a response signal based on the received CSI-RS signal. The device may be further configured to transmit 1730 or cause transmission of the response signal.

[0238] Figure 18 18 is a simplified flow chart illustrating a method 1800 of operating a wireless communication device (e.g., a transmitting node) in accordance with some embodiments. In an embodiment, the device may be configured to transmit 1810 or cause transmission of a sequence of reference signals (RS) to a user equipment (UE) from a plurality of antenna ports. The device may be further configured to identify 1820 or cause identification of a response signal received from the UE. The device may further determine 1830 or cause determination of an estimated scheduling utility function based on the received response signal. The device may be further configured to transmit 1840 or cause transmission of a demodulation reference signal (DMRS) to the UE.

[0239] In some embodiments, Figure 12 、 13 , 14, 15, 16 or some other figures herein, the electronic device(s), network(s), system(s), chip(s) or component(s) or parts or implementations thereof may be configured to perform one or more processes, techniques or methods described herein. As described above, in Figure 17 This process is depicted in .

[0240] In some embodiments, Figure 12 、 13, 14, 15, 16 or some other figures herein, the electronic device(s), network(s), system(s), chip(s) or component(s) or parts or implementations thereof may be configured to perform one or more processes, techniques or methods described herein or parts thereof. As described above, in Figure 18 This process is depicted in .

[0241] Example

[0242] The following is a non-exhaustive list of example embodiments that fall within the scope of the present disclosure. To avoid complexity in providing this disclosure, not all examples listed below are individually and explicitly disclosed, as they are contemplated herein for combination with all other examples listed below and other embodiments disclosed above. Unless one of ordinary skill in the art would understand that the examples listed below and the embodiments disclosed above are not combinable, such examples and embodiments are considered combinable within the scope of this disclosure.

[0243] Example 1 may include a user equipment (UE) device comprising: a device for identifying or causing identification of a channel state information reference signal (CSI-RS) received from a transmit / receive point (TRP); a device for determining or causing determination of a response signal based on the received CSI-RS signal; and a device for sending or causing sending of a response signal.

[0244] Example 2 may include the subject matter of Example 1 or any other example herein, further comprising means for identifying or causing identification of a second received signal.

[0245] Example 3 may include the subject matter of Example 1 or any other example herein, wherein the means for determining or causing determination of the response signal further comprises means for quantizing or causing quantization of the received CSI-RS signal without performing preprocessing, means for quantizing or causing quantization of the received CSI-RS signal by performing preprocessing, or means for quantizing or causing quantization of a subset of the received signal.

[0246] Example 4 may include the subject matter of Example 3 or any other example herein, wherein the response signal further includes an uplink reference signal to enable the TRP to measure the uplink channel to facilitate equalization of the signal received by the TRP.

[0247] Example 5 may include the subject matter of Example 1 or any other example herein, wherein the means for transmitting or causing transmission further comprises means for transmitting or causing transmission using multiple antennas.

[0248] Example 6 may include the subject matter of Example 5 or any other example herein, wherein the means for transmitting or causing the transmitting further comprises means for identifying or causing the identifying of the received beamforming vector prior to transmitting.

[0249] Example 7 may include the subject matter of Example 2 or any other example herein, wherein the apparatus for identifying or causing identification of a second received signal further comprises apparatus for decoding or causing decoding of a demodulation reference signal (DMRS), or apparatus for decoding or causing decoding of data.

[0250] Example 8 may include a transmit / receive point (TRP) device comprising: a device for sending or causing a reference signal (RS) sequence to be sent to a user equipment (UE) from multiple antenna ports; and a device for identifying or causing a response signal received from the UE to be identified; a device for determining or causing an estimated scheduling utility function based on the received response signal; and a device for sending or causing a demodulation reference signal (DMRS) to be sent to the UE.

[0251] Example 9 may include the subject matter of Example 8 or any other example herein, wherein the means for transmitting or causing transmission of an RS sequence from multiple antenna ports is further for transmitting or causing transmission of an RS sequence from multiple antenna ports simultaneously.

[0252] Example 10 may include the subject matter of Example 8 or any other example herein, wherein the means for sending or causing the sending of an RS sequence is further for sending or causing the sending of a precoded channel state information (CSI)-RS.

[0253] Example 11 may include the subject matter of Example 8 or any other example herein, wherein the received response signal comprises a UE-received RS based on a quantization of the transmitted RS sequence.

[0254] Example 12 may include the subject matter of Example 11 or any other example herein, wherein the quantized UE-received RS includes a partially quantized UE-received RS.

[0255] Example 13 may include the subject matter of Example 8 or any other example herein, wherein the means for transmitting or causing the transmitting of the RS sequence is further for transmitting or causing the transmitting of a data stream.

[0256] Example 14 may include the subject matter of Example 13 or any other example herein, wherein the means for sending or causing the sending of the RS sequence is further for sending or causing the sending of the RS sequence using a first codebook.

[0257] Example 15 may include the subject matter of Example 13 or any other example herein, wherein the means for transmitting or causing the transmission of the data stream is further for transmitting or causing the transmission of the data stream using a second codebook.

[0258] Example 16 may include the subject matter of Examples 13-15 or any other examples herein, wherein the first codebook and the second codebook are the same codebook.

[0259] Example 17 may include the subject matter of Examples 13-15 or any other examples herein, further comprising means for uploading or causing the first codebook and / or the second codebook to be uploaded to the TRP.

[0260] Example 18 may include the subject matter of Example 8 or any other example herein, wherein the apparatus for determining or causing determination of an estimated scheduling utility function is further used to determine or causing determination of an estimated scheduling utility function based on a signal to interference plus noise ratio (SINR), leakage interference power, background information, convex optimization, and / or a learning algorithm.

[0261] Example 19 may include the subject matter of Example 8 or any other example herein, wherein the estimated dispatch utility function is optimized with different sets of parameters.

[0262] Example 20 may include the subject matter of Example 8 or any other example herein, wherein the means for transmitting or causing the transmitting is further for transmitting or causing the transmitting using beamforming.

[0263] Example 21 may include a TRP equipped with multiple antenna ports and two codebooks: the first codebook is used to transmit a precoded RS, and the second codebook is used to precode the data stream so that multiple data streams on the same resource element do not interfere with each other.

[0264] Example 22 may include the subject matter of Example 21 or some other examples herein, wherein the same codebook is used to transmit RS and data.

[0265] Example 23 may include the subject matter of Example 21 or other examples herein, wherein the codebook is loaded / updated if the wireless propagation environment changes.

[0266] Example 24 may include a UE equipped with a single antenna, which may quantize the received RS and feed it back to the TRP without any pre-processing of the received signal.

[0267] Example 25 may include the subject matter of Example 24 or some other examples herein, wherein the UE performs some pre-processing on the received signal.

[0268] Example 26 may include the subject matter of Example 24 or some other examples herein, wherein only a subset of the RSs are quantized and fed back.

[0269] Example 27 may include the subject matter of Example 24 or some other examples herein, wherein the UE is equipped with multiple antennas and the receive beamforming vector is pre-fixed.

[0270] Example 28 may include the subject matter of Example 24 or certain other examples herein, wherein the UE does not perform quantization, but instead relays the received signal back to the TRP along with some uplink reference signals that enable the TRP to measure the uplink channel so that the TRP can equalize the received signal.

[0271] Example 29 may include the subject matter of Example 24 or other examples herein, wherein an additional bit is fed back to signal that the measurement codebook needs to be updated by the TRP.

[0272] Example 30 may include a method for resource allocation in a wireless network including one or more TRPs and one or more UEs. The method uses feedback information from the UE to estimate a utility function for different transmission parameter sets.

[0273] Example 31 may include the subject matter of Example 30 or some other example herein, with an algorithm that optimizes an estimated utility function with different sets of parameters.

[0274] Example 32 may include the subject matter of Example 30 or some other example herein, wherein the TRP uses other auxiliary information (such as statistical information about the wireless channel) to estimate the network utility function.

[0275] Example 33 may include a user equipment (UE) device to: identify or cause identification of a channel state information reference signal (CSI-RS) received from a transmit / receive point (TRP); determine or cause determination of a response signal based on the received CSI-RS signal; and send or cause sending of a response signal.

[0276] Example 34 may include the subject matter of Example 33 or any other example herein, further comprising identifying or causing identification of a second received signal.

[0277] Example 35 may include the subject matter of Example 33 or any other example herein, wherein determining or causing determination of the response signal further comprises quantizing or causing quantization of the received CSI-RS signal without performing preprocessing, quantizing or causing quantization of the received CSI-RS signal by performing preprocessing, and quantizing or causing quantization of a subset of the received signal.

[0278] Example 36 may include the subject matter of Example 35 or any other example herein, wherein the response signal further includes an uplink reference signal to enable the TRP to measure the uplink channel to facilitate equalization of the signal received by the TRP.

[0279] Example 37 may include the subject matter of Example 33 or any other example herein, wherein transmitting or causing transmission further comprises transmitting or causing transmission using multiple antennas.

[0280] Example 38 may include the subject matter of Example 37 or any other example herein, wherein sending or causing sending further comprises identifying or causing identification of a received beamforming vector prior to sending.

[0281] Example 39 may include the subject matter of Example 34 or any other example herein, wherein identifying or causing identification of the second received signal further comprises decoding or causing decoding of a demodulation reference signal (DMRS) or decoding or causing decoding of data.

[0282] Example 40 may include a transmit / receive point (TRP) device to: send or cause a reference signal (RS) sequence to be sent from multiple antenna ports to a user equipment (UE); identify or cause a response signal received from the UE to be identified; determine or cause an estimated scheduling utility function based on the received response signal; and send or cause a demodulation reference signal (DMRS) to be sent to the UE.

[0283] Example 41 may include the subject matter of Example 40 or any other example herein, wherein sending or causing transmission of the RS sequence from multiple antenna ports further comprises sending or causing transmission of the RS sequence from the multiple antenna ports simultaneously.

[0284] Example 42 may include the subject matter of Example 40 or any other example herein, wherein sending or causing the sending of the RS sequence further comprises sending or causing the sending of a precoded channel state information (CSI)-RS.

[0285] Example 43 may include the subject matter of Example 40 or any other example herein, wherein the received response signal comprises a UE-received RS quantized based on a transmitted RS sequence.

[0286] Example 44 may include the subject matter of Example 43 or any other example herein, wherein the quantized UE-received RS includes a partially quantized UE-received RS.

[0287] Example 45 may include the subject matter of Example 40 or any other example herein, wherein sending or causing the sending of the RS sequence further comprises sending or causing the sending of a data stream.

[0288] Example 46 may include the subject matter of Example 45 or any other example herein, wherein sending or causing sending of the RS sequence further comprises sending or causing sending of the RS sequence using a first codebook.

[0289] Example 47 may include the subject matter of Example 45 or any other example herein, wherein sending or causing the data stream to be sent further comprises sending or causing the data stream to be sent using a second codebook.

[0290] Example 48 may include the subject matter of Examples 45-47 or any other examples herein, wherein the first codebook and the second codebook are the same codebook.

[0291] Example 49 may include the subject matter of Examples 45-47 or any other examples herein, further comprising uploading or causing the first codebook and / or the second codebook to be uploaded to the TRP.

[0292] Example 50 may include the subject matter of Example 40 or any other example herein, determining or causing determination of an estimated scheduling utility function, and further comprising determining or causing determination of an estimated scheduling utility function based on signal to interference plus noise ratio (SINR), leakage interference power, background information, convex optimization and / or a learning algorithm.

[0293] Example 51 may include the subject matter of Example 40 or any other example herein, wherein the estimated dispatch utility function is optimized with different sets of parameters.

[0294] Example 52 may include the subject matter of Example 40 or any other example herein, wherein transmitting or causing to be transmitted further comprises transmitting or causing to be transmitted using beamforming.

[0295] Example 53 may include a method for implementing a user equipment (UE), the method comprising: identifying or causing identification of a channel state information reference signal (CSI-RS) received from a transmit / receive point (TRP); determining or causing determination of a response signal based on the received CSI-RS signal; and sending or causing sending of the response signal.

[0296] Example 54 may include the subject matter of Example 53 or any other example herein, further comprising identifying or causing identification of the second received signal.

[0297] Example 55 may include the subject matter of Example 53 or any other example herein, wherein determining or causing determination of the response signal further comprises quantizing or causing quantization of the received CSI-RS signal without performing preprocessing, quantizing or causing quantization of the received CSI-RS signal by performing preprocessing, or quantizing or causing quantization of a subset of the received signal.

[0298] Example 56 may include the subject matter of Example 55 or any other example herein, wherein the response signal further includes an uplink reference signal to enable the TRP to measure the uplink channel to facilitate equalization of the signal received by the TRP.

[0299] Example 57 may include the subject matter of Example 53 or any other example herein, wherein transmitting or causing transmission further comprises transmitting or causing transmission using multiple antennas.

[0300] Example 58 may include the subject matter of Example 57 or any other example herein, wherein sending or causing sending further comprises identifying or causing identification of a received beamforming vector prior to sending.

[0301] Example 59 may include the subject matter of Example 54 or any other example herein, wherein identifying or causing identification of the second received signal further comprises decoding or causing decoding of a demodulation reference signal (DMRS), or decoding or causing decoding of data.

[0302] Example 60 may include a method for implementing a transmit / receive point (TRP), the method comprising: sending or causing transmission of a reference signal (RS) sequence to a user equipment (UE) from multiple antenna ports; identifying or causing identification of a response signal received from the UE; determining or causing determination of an estimated scheduling utility function based on the received response signal; and sending or causing transmission of a demodulation reference signal (DMRS) to the UE.

[0303] Example 61 may include the subject matter of Example 60 or any other example herein, wherein sending or causing transmission of the RS sequence from multiple antenna ports further comprises sending or causing transmission of the RS sequence from the multiple antenna ports simultaneously.

[0304] Example 62 may include the subject matter of Example 60 or any other example herein, wherein sending or causing the sending of the RS sequence further comprises sending or causing the sending of a precoded channel state information (CSI)-RS.

[0305] Example 63 may include the subject matter of Example 60 or any other example herein, wherein the received response signal comprises a UE-received RS quantized based on a transmitted RS sequence.

[0306] Example 64 may include the subject matter of Example 63 or any other example herein, wherein the quantized UE-received RS includes a partially quantized UE-received RS.

[0307] Example 65 may include the subject matter of Example 60 or any other example herein, wherein sending or causing the sending of the RS sequence further comprises sending or causing the sending of the data stream.

[0308] Example 66 may include the subject matter of Example 65 or any other example herein, wherein sending or causing sending of the RS sequence further comprises sending or causing sending of the RS sequence using a first codebook.

[0309] Example 67 may include the subject matter of Example 65 or any other example herein, wherein sending or causing the data stream to be sent further comprises sending or causing the data stream to be sent using a second codebook.

[0310] Example 68 may include the subject matter of Examples 65-67 or any other examples herein, wherein the first codebook and the second codebook are the same codebook.

[0311] Example 69 may include the subject matter of Examples 65-67 or any other examples herein, further comprising uploading or causing the first codebook and / or the second codebook to be uploaded to the TRP.

[0312] Example 70 may include the subject matter of Example 60 or any other example herein, wherein determining or causing determination of the estimated scheduling utility function further comprises determining or causing determination of the estimated scheduling utility function based on signal to interference plus noise ratio (SINR), leakage interference power, background information, convex optimization, and / or a learning algorithm.

[0313] Example 71 may include the subject matter of Example 60 or any other example herein, wherein the estimated dispatch utility function is optimized with different sets of parameters.

[0314] Example 72 may include the subject matter of Example 60 or any other example herein, wherein transmitting or causing to be transmitted further comprises transmitting or causing to be transmitted using beamforming.

[0315] Example 73 may include an apparatus comprising means for performing one or more elements of the method of any of or related to Examples 1-72, or any other method or process described herein.

[0316] Example 74 may include one or more non-transitory computer-readable media comprising instructions that, when executed by one or more processors of an electronic device, cause the electronic device to perform one or more elements of any of or related methods in Examples 1-72 or any other method or process described herein.

[0317] Example 75 may include an apparatus including logic, modules, or circuits to perform one or more elements of the method of any of or related to Examples 1-72 or any other method or process described herein.

[0318] Example 76 may include a method, technique, or process as in or related to any of Examples 1-72, or a portion thereof.

[0319] Example 77 may include a device comprising one or more processors and one or more computer-readable media comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform any of the methods, techniques, or processes of or related to Examples 1-72, or portions thereof.

[0320] Example 78 may include a method of communicating in a wireless network as shown and described herein.

[0321] Example 79 may include a system for providing wireless communication as shown and described herein.

[0322] Example 80 may include an apparatus for providing wireless communications as shown and described herein.

[0323] Example 81: An apparatus of a wireless communication device, comprising: circuitry (e.g., a radio frequency circuit) configured to measure reference signals received from multiple antennas of another wireless communication device; and circuitry (e.g., a processing circuit) configured to cause one or more antennas of the wireless communication device to transmit information about the received reference signals back to the other wireless communication device to enable the other wireless communication device to estimate utility functions of different sets of transmission parameters.

[0324] Example 82: The apparatus of Example 81, wherein the circuitry configured to cause one or more antennas of the wireless communication device to transmit information about a received reference signal is further configured to perform some pre-processing of the reference signal to reduce processing at the other wireless communication device to estimate the utility function.

[0325] Example 83: An apparatus of Example 81, wherein the circuit configured to cause one or more antennas of the wireless communication device to transmit information about a received reference signal is also configured to quantize the reference signal, and the information about the received reference signal includes data indicative of the quantized reference signal.

[0326] Example 84: wherein the one or more antennas of the wireless communication device include multiple antennas, and the circuit configured to cause the one or more antennas of the wireless communication device to send information about a received reference signal is also configured to fix a receive beamforming vector before receiving the reference signal.

[0327] Example 85: An apparatus according to Example 81, wherein the information about the received reference signal includes the reference signal itself not quantized by the circuitry configured to cause one or more antennas of the wireless communication device to transmit the information about the received reference signal.

[0328] Example 86: An apparatus according to any one of Examples 81-85, wherein the circuit configured to cause one or more antennas of the wireless communication device to send information about a received reference signal is also configured to generate other reference signals and control the one or more antennas to send the other reference signals to the other wireless communication device to enable the other wireless communication device to measure an uplink channel.

[0329] Example 87: An apparatus according to any one of Examples 81-85, wherein the circuit configured to cause one or more antennas of the wireless communication device to transmit information about a received reference signal is also configured to determine whether a codebook for generating a reference signal at the other wireless communication device should be updated, and to control the RF circuit and the one or more antennas to indicate to the other wireless communication device that the codebook should be updated.

[0330] Example 88: The apparatus of any of Examples 81-85, wherein the wireless communication device comprises a user equipment (UE) and the other wireless communication device comprises a cellular base station.

[0331] Example 89: An apparatus of a cellular base station, comprising: a data storage device configured to store data corresponding to a first codebook and a second codebook, the first codebook being different from the second codebook; and one or more processors configured to: precode a reference signal to be sent to a user equipment (UE); and precode data streams on common resource elements using the second codebook to prevent the data streams from interfering with each other.

[0332] Example 90: The apparatus of Example 89, wherein one or more of the first codebook or the second codebook is updated or replaced by a different codebook in response to: determining that a wireless propagation environment between the cellular base station and the UE has changed; or the UE indicating that the wireless propagation environment has changed.

[0333] Example 91: An apparatus of a radio access network (RAN) node, comprising: a data storage device configured to store data corresponding to feedback information received from a UE; and a processing circuit configured to: estimate a utility function for different sets of transmission parameters based on the feedback information received from the UE; and generate a reference signal to be sent to the UE, the feedback information indicating information about a measurement signal measured by the UE in response to the reference signal being transmitted to it.

[0334] Example 92: The apparatus of Example 91, wherein the processing circuit is configured to precode the reference signal using a first codebook and to precode a data stream to be sent to the UE using a second codebook.

[0335] Example 93: The apparatus of Example 92, wherein the first codebook is the same as the second codebook.

[0336] Example 94: The apparatus of any of Examples 91-93, wherein the processing circuit is configured to optimize the estimated utility function for the different sets of transmission parameters.

[0337] Example 95: The apparatus of any of Examples 91-93, wherein the processing circuit is configured to estimate the utility function taking into account statistical information about a wireless channel.

[0338] Example 96: An apparatus of a user equipment (UE), comprising: a data storage device configured to store a first beamforming codebook and a second beamforming codebook different from the first beamforming codebook; and a processing circuit configured to: use the first beamforming codebook to reduce or compress the size of a receive beam space of multiple antennas of the UE; and use the second beamforming codebook to filter a data-bearing signal received from a cellular base station.

[0339] Example 97: The apparatus of Example 96, wherein the processing circuit is configured to transition to using a third beamforming codebook in place of one or more of the first beamforming codebook or the second beamforming codebook in response to a change in a signal propagation environment.

[0340] Example 98: The apparatus of Example 96, wherein the one or more processors are configured to generate a message to be sent to a cellular base station, the message configured to indicate a plurality of reference signals to be sent by the cellular base station.

[0341] Example 99: The apparatus of Example 98, wherein the processing circuit is configured to generate a message to be sent to a plurality of cellular base stations.

[0342] Example 100: An apparatus according to any one of Examples 96-99, wherein the processing circuit is configured to: estimate the effective channel gain of one or more beam pairs; and generate a message to be sent to a cellular base station, the message indicating the estimated effective channel gain.

[0343] Example 101: The apparatus of any of Examples 96-99, wherein the processing circuit is configured to determine the best receive beam from the second beamforming codebook based on a measurement of a reference signal received from a cellular base station when using the first beamforming codebook.

[0344] Example 102: An apparatus of a user equipment (UE), comprising: a data storage device configured to store sample data indicating information measured from a uniformly sampled receive beam space; and one or more processors configured to: estimate one or more parameters of multiple receive beams of a codebook based on the stored samples; select a receive beam from the codebook based on the estimated one or more parameters; and receive data from a cellular base station using the selected receive beam.

[0345] Example 103: The apparatus of Example 102, wherein the one or more processors are configured to generate an acknowledgement (ACK) message to be sent to the cellular base station, the ACK message indicating that the sample quality of the uniformly sampled receive beam space is sufficient.

[0346] Example 104: The apparatus of Example 103, wherein the one or more processors are configured to classify some samples of the uniformly sampled receive beam space as useful and classify other samples of the uniformly sampled receive beam space as useless.

[0347] Example 105: An apparatus according to any of Examples 102-104, wherein the one or more parameters for selecting the receive beam from the codebook are determined by defining a function that depends on the sample data and potential receive beams, the function being selected to approximate an effective channel gain.

[0348] It will be apparent to those skilled in the art that many changes can be made to the details of the above embodiments without departing from the basic principles of the present disclosure. Therefore, the scope of the present disclosure should be determined solely by the appended claims.

Claims

1. A base station, comprising: A data storage device configured to: store data corresponding to a first codebook and a second codebook, wherein the first codebook is different from the second codebook; and One or more processors configured to: Precoding a reference signal to be sent to an i-th user equipment (UE) among multiple user equipments (UEs) using the first codebook; as well as Precoding the data streams on the common resource elements using the second codebook to prevent the data streams from interfering with each other, In response to the i-th UE indicating that the wireless propagation environment between the base station and the i-th UE has changed, one or more of the first codebook or the second codebook is updated or replaced with a different codebook; wherein the one or more processors are further configured to estimate utility functions for different transmission parameter sets based on feedback information received from the i-th UE, and wherein the feedback information indicates information about a measurement signal measured by the i-th UE in response to the reference signal transmitted to the i-th UE, The utility function associated with the i-th UE includes a signal-to-interference-plus-noise ratio (SINR), which is given by the formula Given, where z i is the feedback information received from the i-th UE, z j is the feedback information received from the UE scheduled on the same resource element, w i is the beamforming vector assigned to the i-th UE, and w j is the beamforming vector assigned to UEs scheduled on the same resource element.

2. The base station according to claim 1, wherein The one or more processors are further configured to: optimizing the estimated utility function for the different sets of transmission parameters; and The utility function is estimated taking into account statistical information about the wireless channel.

3. A method for a base station, the method being executed by one or more processors, wherein: Data corresponding to a first codebook and a second codebook are stored in a data storage device of the base station, the first codebook is different from the second codebook, and the method includes: Precoding a reference signal to be sent to an i-th user equipment (UE) among multiple user equipments (UEs) using the first codebook; Precoding the data streams on the common resource element using the second codebook to prevent the data streams from interfering with each other; In response to an indication by the i-th UE that a radio propagation environment between the base station and the i-th UE has changed, updating or replacing the first codebook or the second codebook with a different codebook; estimating utility functions for different transmission parameter sets based on feedback information received from the i-th UE, wherein the feedback information indicates information about a measurement signal measured by the i-th UE in response to the reference signal transmitted to the i-th UE, The utility function associated with the i-th UE includes a signal-to-interference-plus-noise ratio (SINR), which is given by the formula Given, where z i is the feedback information received from the i-th UE, z j is the feedback information received from the UE scheduled on the same resource element, w i is the beamforming vector assigned to the i-th UE, and w j is the beamforming vector assigned to UEs scheduled on the same resource element.

4. The method according to claim 3, further comprising: optimizing the estimated utility function for the different sets of transmission parameters; as well as The utility function is estimated taking into account statistical information about the wireless channel.

5. A computer-readable storage medium storing instructions, which, when executed by one or more processors, perform the steps of the method according to any one of claims 3 to 4.

6. A computer program product comprising instructions which, when executed by one or more processors, perform the steps of the method according to any one of claims 3 to 4.

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