WO2016164073A1

WO2016164073A1 - Codebook subset restriction for a full dimensional multiple-input multiple-output system

Info

Publication number: WO2016164073A1
Application number: PCT/US2015/062211
Authority: WO
Inventors: Alexei Davydov
Original assignee: Intel Corporation
Priority date: 2015-04-08
Filing date: 2015-11-23
Publication date: 2016-10-13

Abstract

A technology for an apparatus of user equipment (UE) to apply a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network. The UE receives channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel. The UE receives the codebook subset restriction for a precoding matrix indicator (PMI) report corresponding to each of the at least two dimensions. The UE receives a CSI reporting request from an enhanced Node B (eNode B). The UE calculates and reports the CSI according to the CSI configuration, the codebook subset restriction for each of the at least two dimensions, and the CSI reporting request received from the eNode B.

Description

CODEBOOK SUBSET RESTRICTION FOR A FULL DIMENSIONAL MULTIPLE-INPUT MULTIPLE-OUTPUT SYSTEM

BACKGROUND

[0001] Increased use of mobile devices, such as smartphones and tablets, with an expanding number of wireless services offered on the devices, such as streaming video, have placed increased data loads and throughput requirements on wireless networks. To handle the increasing amount of wireless services to an increasing numbers of users, various multiple antenna techniques can be employed in wireless network environments to meet the increasing data and throughput demands. For example, multiple antennas may be implemented at a transmitting device and/or a receiving device in a wireless communications system. The use of multiple antennas at the transmitting device and the receiving device may be referred to as multiple-input-multiple-output (MIMO).

[0002] MIMO technology is the use of multiple antennas at both one or more transmitters (Tx) and one or more receivers ( x). A MIMO system can be used to increase data throughput and link reliability of a network without increasing bandwidth frequencies or increasing transmit power of the network. To achieve the increased data throughput and link reliability, the data communicated between a node and a mobile device can be spread over the multiple antennas to achieve an array gain that improves the spectral efficiency and achieve a diversity gain that increases the link reliability. Massive MIMOs can deploy a large number of elements in antenna arrays. Multiple terminals can be deployed for combining a massive MIMO technology with conventional time and frequency division multiplexing using orthogonal frequency division multiplexing (OFDM).

[0003] Three-dimensional (3D) or full-dimensional (FD) MIMO systems can be used in MIMO networks to enhance the cellular performance by deploying antenna elements in both horizontal and vertical dimensions, e.g. a two dimensional (2D) antenna array. A FD MIMO system can direct communications in two dimensions, i.e. horizontally and vertically, to a location in three dimensional (3D) space. The direction of communications in 3D space can increase the directionality, allowing for increased numbers of communication paths, more focused beamforming, and increased throughput for spatial multiplexing in comparison with traditional two dimensional MIMO systems. [0004] Given the demand of wireless data and rapidly increasing wireless data traffic due to growing popularity among consumers and businesses, addressing the high growth in mobile data traffic and providing improvements in radio interface efficiency and communication technology is of paramount importance. One way to accommodate the ever increasing amount of data that is wirelessly communicated is providing

improvements to 3D or FD MIMO communication systems.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Features and advantages of the disclosure will be apparent from the detailed description which follows, taken in conjunction with the accompanying drawings, which together illustrate, by way of example, features of the disclosure; and, wherein:

[0006] FIG. 1A depicts a one dimensional (ID) antenna array in a two dimensional (2D) multiple-input and multiple-output (MIMO) system in accordance with an example;

[0007] FIG. IB is a 2D antenna array in a three dimensional (3D) MIMO system in accordance with an example;

[0008] FIG. 2 illustrates a table of a number of bits in a codebook subset restriction bitmap for applicable transmission modes in accordance with an example;

[0009] FIG. 3 illustrates a table of a codebook subset restriction for 8 antenna ports in accordance with an example;

[0010] FIG. 4 illustrates a table of a codebook subset restriction for 2D beamforming in accordance with a first example;

[0011 ] FIG. 5 illustrates a table of a codebook subset restriction for 2D beamforming in accordance with a second example;

[0012] FIG. 6 illustrates a table of a codebook subset restriction for 2D beamforming in accordance with a third example;

[0013] FIG. 7 is a flow chart for a channel state information (CSI) reporting procedure with a codebook subset restriction in accordance with an example;

[0014] FIG. 8 depicts the functionality of the computer circuitry of a UE in a cellular network that is operable for channel state information (CSI) reporting with a codebook subset restriction in accordance with an example; [0015] FIG. 9 depicts the functionality of the computer circuitry of a an enhanced Node B (eNodeB) in a cellular network that is operable for configuring codebook subset restriction for channel state information (CSI) report with a in accordance with an example;

[0016] FIG. 10 illustrates a diagram of an electronic device circuitry in accordance with an example;

[0017] FIG. 11 illustrates a diagram of a user equipment (UE) in accordance with an example;

[0018] FIG. 12 illustrates a diagram of example components of a wireless device (e.g. User Equipment "UE") device in accordance with an example; and

[0019] FIG. 13 illustrates a diagram of a node (e.g., eNB) and wireless device (e.g., UE) in accordance with an example.

[0020] Reference will now be made to the exemplary aspects illustrated, and specific language will be used herein to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended.

DETAILED DESCRIPTION

[0021] Before the present disclosure is disclosed and described, it is to be understood that this disclosure is not limited to the particular structures, process actions, or materials disclosed herein, but is extended to equivalents thereof as would be recognized by those ordinarily skilled in the relevant arts. It should also be understood that terminology employed herein is used for the purpose of describing particular examples only and is not intended to be limiting. The same reference numerals in different drawings represent the same element. Numbers provided in flow charts and processes are provided for clarity in illustrating actions and operations and do not necessarily indicate a particular order or sequence.

[0022] In a wireless communications network, throughput can be affected by both the signal strength and interference strength. The throughput of a network can be increased by balancing a ratio between a signal strength and an interference level of nodes in a network. One technique for balancing signal strength and interference strength for nodes in a network can be to use beamforming. Beamforming can be used for an antenna array to direct or control signal transmission directions. In conventional two dimensional (2D) multiple-input and multiple-output (MIMO) systems, beamforming can be performed in a horizontal domain. A 2D MIMO system in a communication system can include a multiplicity of cell sites, each having a node such as an evolved Node B (eNode B) or base station, for sending and receiving signals over one or more antennas

or antenna modules. In one aspect, each antenna module can have one or more receiving antennas and one or more transmit antennas. In another aspect, each antenna module can have one antenna to transmit and receive data.

[0023] A MIMO system can rely on multiple transmitter (Tx) and receiver (Rx) antennas to provide spatial diversity, multiplexing, and array gains in the downlink and uplink channels. In the downlink, the Tx can improve the performance by using channel state information (CSI) regarding the downlink channel by obtaining information from the Rx.

[0024] The CSI can be obtained by the Tx from the Rx (a) from estimation of the uplink channel and by using channel reciprocity of the wireless channel and/or (b) from quantized feedback measured by the Rx.

[0025] The quantized form of CSI feedback can be more general and can be used for both frequency division duplex (FDD) and time division duplex TDD systems. The quantized CSI can include a precoding matrix index (PMI) to assist beamforming or precoding selection at the Tx antennas of an evolved Node B (eNodeB). A set of possible PMI's can be denoted as a codebook. In other words, the Tx antennas use a predefined set of precoding matrices (a "codebook"), and the channel feedback comprises preferred Precoding Matrix Indicators (PMI) that point to precoding matrices selected from the codebook. A codebook can have a codebook subset restriction.

[0026] To differentiate deployments in a third generation partnership project (3 GPP) long term evolution advanced (LTE-A) system, a codebook can be designed to provide reasonable performance in all possible serving directions of an eNodeB. However, depending on the actual deployment of an eNodeB, usage of some PMI's in such a codebook can be avoided. For example, considering the interference that can be created to the neighboring cells, some of the PMI vectors can result in too much interference in the downlink channel. To avoid CSI reporting corresponding to such PMI, LTE-A release 8 (Rel-8) specification defines a codebook subset restriction parameter referred to as "Codebook Subset Restriction." The Codebook Subset Restriction can comprise a bitmap indicating the specific PMI(s) of different rank indicator (RI) restricted at the UE from PMI reporting. A codebook subset restriction can be applied to different transmission modes including open-loop and closed-loop spatial multiplexing, multi-user MIMO, and precoding for the closed-loop with an RI=1. Fig. 2, as described more fully below, provides a number of bits in a codebook subset restriction bitmap for applicable transmission modes.

[0027] As such, a technology is disclosed herein for an apparatus of user equipment (UE) to apply a codebook subset restriction for full dimensional (FD) multiple-input multiple- output (MIMO) in a cellular network. The UE can receive a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel. The UE can receive the codebook subset restriction for precoding matrix indicator (PMI) report corresponding to each of the at least two dimensions. The UE can receive a CSI reporting request from an enhanced Node B (eNode B). The UE can calculate and report the CSI according to the CSI configuration, the codebook subset restriction for each of the at least two dimensions, and the CSI reporting request received from the eNodeB.

[0028] A technology is disclosed herein for an enhanced node B (eNodeB) operable to use a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network. The eNodeB can transmit to a user equipment (UE) a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel. The eNodeB can configure the codebook subset restriction for precoding matrix indicator (PMI) report for a first dimension of the at least two dimensions. The eNodeB can configure the codebook subset restriction for the PMI report for a second dimension of the at least two dimensions. The eNodeB can transmit to the UE, the codebook subset restriction for the PMI reporting corresponding to the first dimension and the second dimension. The eNodeB can send to the UE a CSI reporting request. The eNodeB can receive from the UE, the CSI report according to the CSI configuration, the codebook subset restriction for the first dimension and the second dimension, and the CSI report.

[0029] In one aspect, the CSI report (e.g., CSI feedback) can include information related to channel quality index (CQI), precoding matrix indicator (PMI), and rank indication (RI). The PMI and the RI can be selected from the codebook subset restriction. The CQI can report for the restricted PMI and the RI. In one aspect, the eNodeB can adjust the downlink channel based on the precoder referenced by the restricted PMI.

[0030] In one aspect, the technology is disclosed herein for an apparatus for codebook subset restriction for full dimensional precoding. The apparatus can provide a receiver to receive over a wireless network, from an eNodeB, a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel, a codebook subset restriction for a precoding matrix indicator (PMI) report corresponding to the at least two dimensions, and a CSI reporting request. The apparatus can provide a controller, coupled to the receiver, to calculate, a channel state information for the apparatus using the received CSI reporting configuration, the codebook subset restriction for the at least two dimensions, and the CSI reporting request. The apparatus can provide a transmitter, coupled to the controller, to transmit over the wireless network to the eNodeB, the channel state information for the apparatus. The apparatus can include a transceiver comprising the transmitter and the receiver. The transceiver can also include a baseband processor used to process the information that is transmitted and received.

[0031] FIG. 1A depicts a ID antenna array 102a in a 2D MIMO system 100a. FIG. 1A further depicts a plurality of antenna elements 104a in the ID antenna array 102a. FIG. 1A also shows two arrows emanating from the array 102a in the left and right directions. In one aspect, the antenna array 102a can be used for spatial multiplexing in the horizontal dimension. Each of the antenna elements can correspond to an antenna port. For example, FIG. 1A shows eight antenna elements 104 that each correspond to an antenna port in the antenna array 102a. The two arrows to the right and left depict the horizontal directionality of the ID antenna array 102a that the antenna elements 104a can be adjust to change the coverage area of the communications network.

[0032] The antenna array 102a can be mounted on a transmission point 106a, such as an enhanced Node B (eNodeB B), with a corresponding coverage area 108a. The horizontal directivity provided by the array is depicted by the beam direction geometries, 110a, 112a, and 114a. A beam direction geometry, also referred to as a radiation pattern, can depict a region with respect to the transmission point where a corresponding signal is highest, but the corresponding signal can be present in other regions as well. The curved arrow indicates that the three different beam direction geometries, or side lobes, that belong to a continuum of different possibilities. [0033] FIG. IB depicts a 2D antenna array 102b in a three dimensional (3D) or full dimensional (FD) MIMO system 100b. FIG. IB further depicts a plurality of antenna elements 104b in the 2D antenna array 102b. The 2D array comprises antenna columns 116 in the 2D antenna array 102b. FIG. IB also shows three arrows emanating from the antenna array 102b in different directions, two dashed arrows pointing upward and downward and the solid arrow normal to the plane of the array, depict the directionality that the antenna array 102b in the vertical dimension. The array can be mounted on a transmission point 106b, such as an eNodeB B, with a corresponding coverage area 108b. The vertical directivity provided by the antenna array 102b is depicted by two different beam direction geometries, a first beam direction geometry 118 and a second beam direction geometry 120. As discussed in the preceding paragraphs, a beam direction geometry can depict a region with respect to the transmission point where a

corresponding signal is highest, but the corresponding signal can be present in other regions as well. The curved arrow indicates that the three different beam direction geometries or side lobes that belong to a continuum of different possibilities.

[0034] FIG. IB depicts the antenna elements 104b of the antenna array 102b providing for vertical directionality. Additionally, the antenna elements 104b of the antenna array 102b can also provide for horizontal directionality, as discussed in the preceding paragraphs related to FIG. 1A. Therefore, the communications can be directed in two dimensions to point toward a location in three-dimensional space.

[0035] In the 3D MIMO system, a radiation pattern of a transmitting antenna at a node can be tilted along a vertical axis. The degree of the vertical tilting or the tilting angle can be measured relative to a horizontal plain of reference. The tilting angle can be referred to as the downtilt angle of the antenna. The downtilt angle of the antenna can be measured to be positive from the horizontal reference plain of the antenna towards the ground. For example, an antenna with a downtilt angle of 10 degrees tilts towards the ground at a 10- degree angle relative to the horizontal reference.

[0036] The antenna elements 104b in the antenna array 102b can have their phases and amplitudes configured to enable the antenna array 102b to transmit to a desired coverage area, which is a geographic area in which a mobile terminal can receive a signal with a sufficient strength to communicate with a node associated with the antenna array. A coverage area range and/or scope of an antenna array can be affected by the electronic downtilt angle of each antenna and/or downtilt angles of surrounding and/or adjacent antennas in the antenna array 102b.

[0037] For a traditional 2D MIMO system, the downtilt of the antenna elements in an antenna array of an eNode B can be held constant and a user equipment (UE) can measure a reference signal received power (RSRP) and/or a reference signal received quality

(RSRQ) for each node associated with a cell in order to assist the eNode B to make a cell association decision. In one aspect, the RSRP can be used for intra-frequency cell association and the RSRQ can be used for inter-frequency cell association.

[0038] RSRP can be defined as a linear average of the power contributions (in Watts) of resource elements that carry cell-specific reference signals within a selected measurement frequency bandwidth. A reference point for the RSRP can be the antenna connector of the UE. In one aspect, when a receiver diversity is used by the UE, the RSRP cannot be lower than the corresponding RSRP of any of the individual diversity branches.

[0039] For a 3D/FD MIMO system, beamforming can be performed in both the horizontal and vertical dimensions. In 3D/FD MIMO systems, elevation or vertical beamforming can be used to either increase the signal strength of a cell and/or decrease signal interference to neighboring cells. In one aspect, elevation beamforming in 3D/FD MIMO systems can be used to optimize cell association selection by the eNode B. For example, elevation beamforming can be used to optimize an elevation and downtilting of each cell in the 3D/FD MIMO system for different traffic distributions. In one aspect, maximizing a signal strength or minimizing a signal interference separately or independent of each other cannot optimize or increase a signal to interference ratio (SIR), signal to noise ratio (SNR), or signal to interference plus noise ratio (SINR) of a network. In one aspect, interference minimization and signal strength maximization can be performed together to maximize the SIR, SNR, and/or SINR of a network, e.g. maximize throughput.

[0040] FIG. 2 illustrates a table of number of bits in a codebook subset restriction bitmap for applicable transmission modes in accordance with an example. In FIG. 2, "Ac" can represent the number of bits included in "Codebook Subset Restriction" and the number of all the available precoding matrixes in a corresponding transmission mode. PMI codebook subset restrictions in the LTE release 8/9 (Rel-8/9) can be defined for 2 and 4 antenna ports, where the size of a codebook can be limited in size. With 4 antenna ports, for example, the size of a codebook at each rank can be 16 PMI's, and then 64 bits in total can be required for a codebook subset restriction for all 4 supported ranks. However for an 8-Tx antenna, where a dual-codebook feedback mechanism can be assumed, another approach of the codebook subset restriction can be used. More specifically, an 8-antenna port codebook in the 3GPP Rel-10 can be represented as a two-dimensional table where a row index il corresponds to an index in a codebook CI and can be represented as a first PMI in a feedback and a column index i2 corresponds to an index in a codebook C2 and can be represented as a second PMI in a feedback. The index il in the first codebook selects the set of the adjacent discrete Fourier transform (DFT) beams for beamforming of antenna set with the same polarization and index i2 selects a DFT beam in the DFT set and co-phasing coefficient for the combining of two DFT beamformed antennas groups with different polarizations. More specifically, an 8 antenna ports PMI can be a product of two matrices Wl e CI and W2 e C2, i.e. W = W1 *W2, where Wl can present the long- term/wideband properties of the a radio channel and W2 can capture the short- term/frequency-selective properties of the radio channel.

[0041] The codebook subset restriction in an 8-Tx antenna, instead of individual PMI restriction, can independently restrict the PMIs in the codebook CI and C2, i.e. the codebook subset restriction can restrict the set of DFT vectors and restrict the DFT beam selection and co-phasing. In order to reduce the signaling overhead, the restriction of the DFT vector sets can be assumed to be common for ranks { 1,2}, {3,4}, {5,6,7} and {8}.

[0042] FIG. 3 illustrates a table of a codebook subset restriction for applicable transmission modes in accordance with an example. In some aspects, a Kronecker- product (KP) based PMI feedback for FD-MIMO systems can be used. Kronecker-based PMI feedback can be used to support 3D/FD-MIMO precoding with a planar (2D) antenna array. The Kronecker structure of PMI can be based on the observation that a full channel precoder in a planar antenna array can be approximated as a Kronecker product of a vertical precoder and a horizontal precoder, i.e., for example,

W = W_v (¾ W_H, (1)

[0043] where W_v denotes vertical precoder (PMI), and W_H denotes horizontal precoder (PMI),

[0044] Each precoder (horizontal or vertical) of the Kronecker product based FD- MIMO codebook may have a dual codebook structure. For example, the horizontal precoder can be defined as %¾ = Wm*W₂H, where PMI for Wm indicates a set of beams in the horizontal domain and W2H selects the beams in the indicated by Wm et and adjust the phases if multiple beams and polarization are used.

[0045] To support KP based PMI feedback, the UE can measure a vertical channel component hy and a horizontal channel component hn and calculate the horizontal WH and vertical (elevation) precoders Wy based on those channel estimates. Then, the UE or eNodeB can form the full channel precoder as described in the equation above.

[0046] Considering dual codebook structure with 8 antenna ports as an example in the horizontal dimension and single codebook structure in the vertical domain, KP precoding can be defined as follows:

W = (W_1HW_2H) ® W_V = (W_1H <g) W_V)W_2H, (2) where W_v denotes an vertical (or elevation) PMI estimated by the UE from the vertical channel component and by using vertical (elevation) PMI codebook denoted as Cv and W_H = W_1HW_2H denotes an horizontal (or azimuth) PMI estimated by the UE from the horizontal channel component and by using horizontal (azimuth) PMI codebook denoted as CH. In some aspects, a codebook can be used for subset restriction for the vertical beamforming. Depending on the structure of the codebook, several alternatives of the codebook subset restriction can be used. In some aspects, a codebook for a subset restriction signaling for the CSI calculation and reporting in the LTE-A system with vertical (elevation) beamforming can be used.

[0047] FIG. 4 is a table of a codebook subset restriction for 2D beamforming. FIG.4 illustrates an example of the codebook subset restriction for vertical and horizontal precoding, assuming dual codebook structure for horizontal precoding. In one aspect, the codebook subset restriction for the 2D beamforming includes codebook subset restriction for horizontal and vertical dimensions. For vertical precoding the codebook subset restriction can include a bitmap, where Xi bits of the bitmap are allocated for independent PMI/RI restriction of the vertical beamforming codebook for the rank i. In FIG. 4, Cv denotes the vertical codebook, C1H the horizontal codebook 1, and C2H the horizontal codebook 2.

[0048] FIG. 5 illustrates a table of a codebook subset restriction for 2D beamforming in accordance with a second example. In an aspect, the codebook subset restriction for the 2D beamforming includes codebook subset restriction for horizontal and vertical dimensions. The codebook subset restriction for the vertical precoding can include a bitmap, where "X" bits of the bitmap are allocated for the vertical codebook for all supported ranks. It is assumed that the PMI restriction in W_v is identical to for all ranks. FIG. 5 illustrates an example of codebook subset restriction for vertical and horizontal precoding assuming dual codebook structure in the horizontal channel.

[0049] FIG. 6 illustrates a table of a codebook subset restriction for 2D beamforming in accordance with a third example. In one aspect, the codebook subset restriction for the 2D beamforming includes codebook subset restriction for horizontal and vertical dimensions. A different group of the supported ranks can have the same set of the restricted PMIs in the codebook for the vertical precoding. For example, as shown in FIG. 6, for antenna configuration with dual codebook structure, the same codebook subset restriction for W_v can be defined for ranks 1-2, 3-4, 5-7 and 8, where each restriction comprises Xj bitmap.

[0050] In some aspects, a UE, upon reception of the codebook subset restriction for vertical beamforming, can limit a search of the optimal vertical PMIs to the set of the PMI not restricted by the serving cell. The channel quality indicator (CQI) can be reported based on the unrestricted set of PMIs.

[0051] FIG. 7 is a flow chart 700 for a channel state information (CSI) reporting procedure with a codebook subset restriction in accordance with an example. The functionality of FIG. 7 can be implemented as a method or the functionality can be executed as instructions on a machine, where the instructions are included on at least one computer readable medium or one non-transitory machine-readable storage medium. Computer circuitry (e.g., one or more processors and memory) of a user equipment (UE) can be configured to configure a CSI report at the UE with two dimensional (2D) PMI, as in action 710. The computer circuitry of an enhanced node B (eNodeB) can be configured to configure codebook subset restriction for PMI's reporting for a first dimension, as in action 720. The computer circuitry can also be configured to configure codebook subset restriction for PMI's reporting for a second dimension, as in action 730. The computer circuitry of the eNode B can be configured to request CSI reporting from the UE in accordance to the CSI configuration and codebook subset restriction, as in action 740. The computer circuitry of the eNodeB can be configured to receive the CSI report from the UE, as in action 750. [0052] In one configuration, a first processor can perform the operations in action 710, 720, 730, 740, and 750. The first processor can be a single processor, or alternatively, the first processor can be comprised of one or more separate processors. In one configuration, a second processor can perform the operations in action 710, 720, 730, 740, and/or750. In one aspect, as part of action 710, 720, 730, 740, and/or 750, FIG. 7 can include the CSI reporting configuration for each of the at least two dimensions further includes a configuration of PMI report and rank indicator (RI) report from a codebook subset restriction for the at least two dimensions, and/or the CSI reporting configuration for each of the at least two dimensions further includes configuration of horizontal PMI report and vertical PMI report. Example 4 includes the apparatus of example 1, wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report.

[0053] In one aspect, as part of action 710, 720, 730, 740, and/or 750, the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3 GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification. The codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer. A codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer. A codebook subset restriction for at least one dimension comprises a bitmap, wherein a different group of supported ranks include a same vertical PMI codebook subset restriction. The same vertical PMI codebook subset restriction is defined for each different group of the supported ranks. Each different group of the supported ranks can include a first group including rank 1 and rank 2, a second group including rank 3 and rank 4, a third group including rank 5, rank 6, and rank 7, and a fourth group including rank 8.

[0054] FIG. 8 depicts the functionality 800 of the computer circuitry of a UE in a cellular network that is operable to apply a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO), as shown in the flow chart in FIG. 8. The functionality 800 can be implemented as a method or the functionality can be executed as instructions on a machine, where the instructions are included on at least one computer readable medium or one non-transitory machine-readable storage medium. The computer circuitry (e.g., one or more processors and memory) can be configured to receive, at the UE, a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel, as in action 810. The computer circuitry can be configured to receive, at the UE, the codebook subset restriction for precoding matrix indicator (PMI) reporting corresponding to each of the at least two dimensions, as in action 820. The computer circuitry can be configured to receive, at the UE, a CSI reporting request from an enhanced Node B (eNodeB), as in action 830. The computer circuitry can be configured to calculate and report, from the UE, the CSI according to the CSI configuration, the codebook subset restriction for each of the at least two dimensions, and the CSI reporting request received from the eNodeB, as in action 840. That is, the UE can calculate a CSI for the UE using the received CSI reporting configuration, the codebook subset restriction for the at least two dimensions, and the CSI reporting request from the eNodeB. The computer circuitry can be configured to transmit, by the UE, the CSI to the eNodeB, as in action 850.

[0055] In one aspect, the one or more processors and memory of FIG. 8 can be configured to include a CSI reporting configuration for each of the at least two dimensions and include a configuration of PMI report and rank indicator (RI) report from a codebook subset restriction for the at least two dimensions. The CSI reporting configuration for each of the at least two dimensions can further include configuration of horizontal PMI report and vertical PMI report. The codebook subset restriction for each of the at least two dimensions can comprise a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report. The codebook subset restriction for a first dimension of the at least two dimensions can be in accordance to a third generation partnership project (3GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification.

[0056] The codebook subset restriction for a second dimension of the at least two dimensions can comprise a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer. A codebook subset restriction for at least one dimension can comprise a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer. [0057] In one configuration, a first processor can perform the operations in action 810, 820, 830, 840, and 850. The first processor can be a single processor, or alternatively, the first processor can be comprised of one or more separate processors. In one configuration, a second processor can perform the operations in action 810, 820, 830, 840, and/or 850.

[0058] FIG. 9 depicts the functionality 900 of the computer circuitry of a an enhanced Node B (eNodeB) in a cellular network that is operable for using a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network, as shown in the flow chart in FIG. 9. The functionality 900 can be implemented as a method or the functionality can be executed as instructions on a machine, where the instructions are included on at least one computer readable medium or one non-transitory machine readable storage medium. The computer circuitry can be configured to transmit to a user equipment (UE) a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel, as in action 910. The computer circuitry can be configured to configure the codebook subset restriction for precoding matrix indicator (PMI) reporting for a first dimension of the at least two dimensions, as in action 920. The computer circuitry can be configured to configure the codebook subset restriction for the PMI reporting for a second dimension of the at least two dimensions, as in action 930. The computer circuitry can be configured to transmit to the UE, the codebook subset restriction for the PMI reporting corresponding to the first dimension and the second dimension, as in action 940. The computer circuitry can be configured to send to the UE a CSI reporting request, as in action 950. The computer circuitry can be configured to receive from the UE, the CSI report according to the CSI configuration, the codebook subset restriction for the first dimension and the second dimension, and the CSI reporting, as in action 950.

[0059] In one configuration, a first processor can perform the operations in action 910, 920, 930, 940, and 950. The first processor can be a single processor, or alternatively, the first processor can be comprised of one or more separate processors. In one configuration, a second processor can perform the operations in action 910, 920, 930, 940, and/or 950.Moreover, in association with action 910, 920, 930, 940, and/or 950, the CSI reporting configuration for each of the at least two dimensions can further include a configuration of the PMI report and a rank indicator (RI) report from a codebook subset restriction. The CSI reporting configuration for each of the at least two dimensions further includes a configuration of a horizontal PMI report and a vertical PMI report. The codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report. The codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification. The codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer.

[0060] The codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer. The codebook subset restriction for at least one dimension comprises a bitmap, wherein a different group of supported ranks include the same vertical PMI codebook subset restriction. The common vertical PMI codebook subset restriction is defined for each different group of the supported ranks comprising a first group including rank 1 and rank 2, a second group including rank 3 and rank 4, a third group including rank 5, rank 6, and rank 7, and a fourth group including rank 8, wherein each PMI restriction comprises Xj bits.

[0061] FIG. 10 illustrates a diagram of an electronic device circuitry 1000 that can be eNodeB circuitry, the UE circuitry, or some other type of circuitry in accordance with various aspects. In aspects, the electronic device circuitry can be, or can be incorporated into or otherwise a part of, an eNodeB, a UE, or some other type of electronic device. In aspects, the electronic device circuitry can include radio transmit circuitry and receive circuitry coupled to control circuitry. In aspects, the transmit and/or receive circuitry can be elements or modules of transceiver circuitry, as shown. The electronic device circuitry 1000 can be coupled with one or more plurality of antenna elements of one or more antennas. The electronic device circuitry 1000 and/or the components of the electronic device circuitry 1000 can be configured to perform operations similar to those described elsewhere in this disclosure.

[0062] Electronic device circuitry 1000 can be a UE apparatus for codebook subset restriction for full dimensional precoding. The receive circuitry can be to receive over a wireless network, from an eNodeB, a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel, a codebook subset restriction for a precoding matrix indicator (PMI) report corresponding to the at least two dimensions, and a CSI reporting request.

[0063] Control circuitry can include a configuration to calculate a channel state information for the UE apparatus using the received CSI reporting configuration, the codebook subset restriction for the at least two dimensions, and the CSI reporting request. The transmit circuitry can include a configuration to transmit over the wireless network to the eNodeB, the channel state information for the UE apparatus. The CSI reporting configuration for the at least two dimensions of the downlink channel can include a configuration of a precoding matrix index (PMI) and a rank indicator (RI) reporting from the codebook subset restriction. The CSI reporting configuration for the at least two dimensions can include a configuration of an horizontal and a vertical PMI reporting. The codebook subset restriction for the at least two dimensions can include a bitmap with bits, wherein the bits of the bitmap can be equal to 0 or 1 and can indicate when the PMI corresponding to a rank indicator (RI) in the codebook subset restriction can be restricted from the PMI reporting. The codebook subset restriction for a first dimension can be in accordance to LTE-A Rel-12 specification. The codebook subset restriction for the second dimension comprises the bitmap, wherein Xi bits of the bitmap can be allocated for an independent restriction of a vertical beamforming codebook for a rank i, and Xi can be an integer. The codebook subset restriction for at least one dimension includes the bitmap, where X bits of the bitmap can be allocated for a common restriction of a vertical PMI codebook for all supported ranks, and X can be an integer. The codebook subset restriction for at least one dimension can include the bitmap, wherein for a different group of the supported ranks can have a common vertical PMI codebook subset restriction. The codebook subset restriction can be the same for ranks 1-2, 3-4, 5-7, and 8, wherein a PMI restriction can include Xj bits when 8 CSI-RS antenna ports are configured for CSI reporting on a first dimension.

[0064] As used herein, the term "circuitry" can refer to, be part of, or include

an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor

(shared, dedicated, or group), and/or memory (shared, dedicated, or group) that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable hardware components that provide the described functionality. In some aspects, the electronic device circuitry can be implemented in, or functions associated with the circuitry can be implemented by, one or more software or firmware modules.

[0065] In some aspects, the circuitry of FIG. 10 can be configured to perform one or more processes such as the process of FIGS. 7-9. For example, in aspects where the electronic device circuitry can be a UE, or can be incorporated into or otherwise part of a UE, the process can include functionality 800, as show in Figure 8.

[0066] Examples

[0067] Example 1 includes an apparatus of a user equipment (UE), the apparatus comprising computer circuitry operable to apply a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network, the computer circuitry configured to: receive, at the UE, a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel; receive, at the UE, the codebook subset restriction for a precoding matrix indicator (PMI) report corresponding to each of the at least two dimensions; receive, at the UE, a CSI reporting request from an enhanced Node B (eNode B); and calculate and report, from the UE, CSI according to the CSI reporting configuration, the codebook subset restriction for each of the at least two dimensions, and the CSI reporting request received from the eNode B.

[0068] Example 2 includes the apparatus of example 1, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of PMI report and rank indicator (RI) report from a codebook subset restriction for the at least two dimensions.

[0069] Example 3 includes the apparatus of example 2, wherein the CSI reporting configuration for each of the at least two dimensions further includes configuration of horizontal PMI report and vertical PMI report.

[0070] Example 4 includes the apparatus of example 1, wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report.

[0071] Example 5 includes the apparatus of example 4, wherein the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification.

[0072] Example 6 includes the apparatus of example 4, wherein the codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer.

[0073] Example 7 includes the apparatus of example 4, wherein a codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer.

[0074] Example 8 includes the apparatus of example 4, wherein a codebook subset restriction for at least one dimension comprises a bitmap, wherein a different group of supported ranks include a same vertical PMI codebook subset restriction.

[0075] Example 9 includes the apparatus of example 8, wherein the same vertical PMI codebook subset restriction is defined for each different group of the supported ranks.

[0076] Example 10 includes the apparatus of example 9, wherein each different group of the supported ranks can include a first group including rank 1 and rank 2, a second group including rank 3 and rank 4, a third group including rank 5, rank 6, and rank 7, and a fourth group including rank 8.

[0077] Example 11 can include an apparatus of an enhanced node B (eNode B) operable to use a codebook subset restriction for full dimensional (FD) multiple-input multiple- output (MIMO) in a cellular network, the eNode B having computer circuitry configured to: transmit to a user equipment (UE) a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel; configure the codebook subset restriction for precoding matrix indicator (PMI) report for a first dimension of the at least two dimensions; configure the codebook subset restriction for the PMI report for a second dimension of the at least two dimensions; transmit to the UE, the codebook subset restriction for the PMI report corresponding to the first dimension and the second dimension; send to the UE a CSI reporting request; and receive from the UE, a CSI report according to the CSI reporting configuration, the codebook subset restriction for the first dimension and the second dimension, and the CSI reporting request. [0078] Example 12 includes the apparatus of example 11, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of the PMI report and a rank indicator (RI) report from a codebook subset restriction.

[0079] Example 13 includes the apparatus of example 12, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of a horizontal PMI report and a vertical PMI report.

[0080] Example 14 includes the apparatus of example 11, wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report.

[0081] Example 15 includes the apparatus of example 14, wherein the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification.

[0082] Example 16 includes the apparatus of example 14, wherein the codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer.

[0083] Example 17 includes the apparatus of example 14, wherein the codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer.

[0084] Example 18 includes the apparatus of example 14, wherein the codebook subset restriction for at least one dimension comprises a bitmap, wherein a different group of supported ranks include the same vertical PMI codebook subset restriction.

[0085] Example 19 includes the apparatus of example 18, wherein the common vertical PMI codebook subset restriction is defined for each different group of the supported ranks comprising a first group including rank 1 and rank 2, a second group including rank 3 and rank 4, a third group including rank 5, rank 6, and rank 7, and a fourth group including rank 8, wherein each PMI restriction comprises Xj bits.

[0086] Example 20 includes at least one non-transitory machine readable storage medium having instructions embodied thereon for performing a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network, the instructions when executed perform the following: receive, at the UE, a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel; receive, at the UE, the codebook subset restriction for a precoding matrix indicator (PMI) report corresponding to each of the at least two dimensions; receive, at the UE, a CSI reporting request from an enhanced Node B (eNode B); calculate, from the UE, the CSI according to the CSI configuration, the codebook subset restriction for each of the at least two dimensions, and the CSI reporting request received from the eNode B; and transmit the CSI to the eNode B.

[0087] Example 21 includes the computer-readable storage medium of example 20, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of PMI report and rank indicator (RI) report from a codebook subset restriction for the at least two dimensions.

[0088] Example 22 includes the computer-readable storage medium of example 21, wherein the CSI reporting configuration for each of the at least two dimensions further includes configuration of horizontal PMI report and vertical PMI report.

[0089] Example 23 includes the computer-readable storage medium of example 20, wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report.

[0090] Example 24 includes the computer-readable storage medium of example 20, wherein the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3 GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification.

[0091] Example 25 includes the computer-readable storage medium of example 20, wherein the codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer.

[0092] Example 26 includes the computer-readable storage medium of example 20, wherein a codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer.

[0093] Example 27 includes an apparatus of a user equipment (UE) operable to apply a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network, the apparatus comprising one or more processors and memory configured to receive, at the UE, a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel; receive, at the UE, the codebook subset restriction for a precoding matrix indicator (PMI) report corresponding to each of the at least two dimensions; receive, at the UE, a CSI reporting request from an enhanced Node B (eNode B); and calculate and report, from the UE, CSI according to the CSI reporting configuration, the codebook subset restriction for each of the at least two dimensions, and the CSI reporting request received from the eNode B.

[0094] Example 28 includes the apparatus of example 27, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of PMI report and rank indicator (RI) report from a codebook subset restriction for the at least two dimensions.

[0095] Example 29 includes the apparatus of example 27 or 28, wherein the CSI reporting configuration for each of the at least two dimensions further includes configuration of horizontal PMI report and vertical PMI report.

[0096] Example 30 includes the apparatus of example 27, wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report.

[0097] Example 31 includes the apparatus of examples 27, wherein the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3 GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification.

[0098] Example 32 includes the apparatus of examples 27 or 30, wherein the codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer. [0099] Example 33 includes the apparatus of examples 27, wherein a codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer.

[00100] Example 34 includes the apparatus of examples 27, wherein a codebook subset restriction for at least one dimension comprises a bitmap, wherein a different group of supported ranks include a same vertical PMI codebook subset restriction.

[00101] Example 35 includes the apparatus of examples 27 or 34, wherein the same vertical PMI codebook subset restriction is defined for each different group of the supported ranks.

[00102] Example 36 includes the apparatus of example 35, wherein each different group of the supported ranks can include a first group including rank 1 and rank 2, a second group including rank 3 and rank 4, a third group including rank 5, rank 6, and rank 7, and a fourth group including rank 8.

[00103] Example 37 includes an apparatus of an enhanced node B (eNode B) operable to use a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network, the apparatus comprising one or more processors and memory configured to: transmit to a user equipment (UE) a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel;

configure the codebook subset restriction for precoding matrix indicator (PMI) report for a first dimension of the at least two dimensions; configure the codebook subset restriction for the PMI report for a second dimension of the at least two dimensions; transmit to the UE, the codebook subset restriction for the PMI report corresponding to the first dimension and the second dimension; send to the UE a CSI reporting request; and receive from the UE, a CSI report according to the CSI reporting configuration, the codebook subset restriction for the first dimension and the second dimension, and the CSI reporting request.

[00104] Example 38 includes the apparatus of example 37, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of the PMI report and a rank indicator (RI) report from a codebook subset restriction.

[00105] Example 39 includes the apparatus of example 37 or 38, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of a horizontal PMI report and a vertical PMI report.

[00106] Example 40 includes the apparatus of examples 37, wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report.

[00107] Example 41 includes the apparatus of examples 37, wherein the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3 GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification.

[00108] Example 42 includes the apparatus of examples 37, wherein the codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer.

[00109] Example 43 includes the apparatus of examples 37, wherein the codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer.

[00110] Example 44 includes the apparatus of examples 37, wherein the codebook subset restriction for at least one dimension comprises a bitmap, wherein a different group of supported ranks include the same vertical PMI codebook subset restriction.

[0011 1] Example 45 includes the apparatus of examples 37 or 44, wherein the common vertical PMI codebook subset restriction is defined for each different group of the supported ranks comprising a first group including rank 1 and rank 2, a second group including rank 3 and rank 4, a third group including rank 5, rank 6, and rank 7, and a fourth group including rank 8, wherein each PMI restriction comprises Xj bits.

[00112] Example 50 includes at least one non-transitory machine readable storage medium having instructions embodied thereon for performing a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network, the instructions when executed perform the following: receive, at the UE, a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel; receive, at the UE, the codebook subset restriction for a precoding matrix indicator (PMI) report corresponding to each of the at least two dimensions;

receive, at the UE, a CSI reporting request from an enhanced Node B (eNode B);

calculate, from the UE, the CSI according to the CSI configuration, the codebook subset restriction for each of the at least two dimensions, and the CSI reporting request received from the eNode B; and transmit the CSI to the eNode B.

[00113] Example 51 includes the computer-readable storage medium of example 50, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of PMI report and rank indicator (RI) report from a codebook subset restriction for the at least two dimensions.

[00114] Example 52 includes the computer-readable storage medium of example 50 or 51, wherein the CSI reporting configuration for each of the at least two dimensions further includes configuration of horizontal PMI report and vertical PMI report.

[00115] Example 53 includes the computer-readable storage medium of example 51 , wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report.

[00116] Example 54 includes the computer-readable storage medium of example 52, wherein the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3 GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification.

[00117] Example 55 includes the computer-readable storage medium of example 53 or 54 wherein the codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer.

[00118] Example 56 includes the computer-readable storage medium of examples 50, wherein a codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer.

[00119] Example 57 apparatus of a user equipment (UE) operable to apply a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network, the apparatus comprising one or more processors and memory configured to: receive, at the UE, a channel state information (CSI) reporting

configuration for at least two dimensions of a downlink channel; receive, at the UE, the codebook subset restriction for a precoding matrix indicator (PMI) report corresponding to each of the at least two dimensions; receive, at the UE, a CSI reporting request from an enhanced Node B (eNode B); and calculate and report, from the UE, CSI according to the CSI reporting configuration, the codebook subset restriction for each of the at least two dimensions, and the CSI reporting request received from the eNode B.

[00120] Example 58 includes the apparatus of example 57, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of PMI report and rank indicator (RI) report from a codebook subset restriction for the at least two dimensions, a configuration of horizontal PMI report and vertical PMI report.

[00121] Example 59 includes the apparatus of 57 or 58, wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report, or the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification, wherein the codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer.

[00122] Example 60 includes the apparatus of 57 to 59, wherein a codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer, or a codebook subset restriction for at least one dimension comprises a bitmap, wherein a different group of supported ranks include a same vertical PMI codebook subset restriction.

[00123] Example 61 includes the apparatus of example 59 or 60, wherein a codebook subset restriction for at least one dimension comprises a bitmap, wherein a different group of supported ranks include a same vertical PMI codebook subset restriction, wherein the same vertical PMI codebook subset restriction is defined for each different group of the supported ranks, wherein each different group of the supported ranks can include a first group including rank 1 and rank 2, a second group including rank 3 and rank 4, a third group including rank 5, rank 6, and rank 7, and a fourth group including rank 8.

[00124] Example 62 includes an apparatus of an enhanced node B (eNode B) operable to use a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network, the apparatus comprising one or more processors and memory configured to: transmit to a user equipment (UE) a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel;

[00125] Example 63 includes the apparatus of example 62, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of the PMI report and a rank indicator (RI) report from a codebook subset restriction, or the CSI reporting configuration for each of the at least two dimensions further includes a configuration of an horizontal PMI report and a vertical PMI report.

[00126] Example 64 includes the apparatus of example 62 or 63, wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report, or the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification.

[00127] Example 65 includes the apparatus of example 62 to 64, wherein the codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer, or the codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer.

[00128] Example 66 includes the apparatus of example 64 or 65, wherein the codebook subset restriction for at least one dimension comprises a bitmap, wherein a different group of supported ranks include the same vertical PMI codebook subset restriction, wherein the common vertical PMI codebook subset restriction is defined for each different group of the supported ranks comprising a first group including rank 1 and rank 2, a second group including rank 3 and rank 4, a third group including rank 5, rank 6, and rank 7, and a fourth group including rank 8, wherein each PMI restriction comprises Xj bits.

[00129] Example 67 includes at least one non-transitory machine readable storage medium having instructions embodied thereon for performing a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network, the instructions when executed perform the following: receive, at the UE, a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel; receive, at the UE, the codebook subset restriction for a precoding matrix indicator (PMI) report corresponding to each of the at least two dimensions;

receive, at the UE, a CSI reporting request from an enhanced Node B (eNode B);

[00130] Example 68 includes the computer-readable storage medium of example 67, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of PMI report and rank indicator (RI) report from a codebook subset restriction for the at least two dimensions, or the CSI reporting configuration for each of the at least two dimensions further includes configuration of horizontal PMI report and vertical PMI report.

[00131] Example 69 includes the computer-readable storage medium of example 67 or

68, wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report.

[00132] Example 70 includes the computer-readable storage medium of examples 67 to

69, wherein the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3 GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification.

[00133] Example 71 includes the computer-readable storage medium of example 69 or 70, wherein the codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer, or a codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer.

[00134] Example 72 includes a device for performing a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network, the device comprising: means for receiving, at the UE, a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel; means for receiving, at the UE, the codebook subset restriction for a precoding matrix indicator (PMI) report corresponding to each of the at least two dimensions; means for receiving, at the UE, a CSI reporting request from an enhanced Node B (eNode B); means for calculating, from the UE, the CSI according to the CSI configuration, the codebook subset restriction for each of the at least two dimensions, and the CSI reporting request received from the eNode B; and means for transmitting the CSI to the eNode B.

[00135] Example 73 includes the device of example 72, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of PMI report and rank indicator (RI) report from a codebook subset restriction for the at least two dimensions.

[00136] Example 74 includes the device of example 72 or 73, wherein the CSI reporting configuration for each of the at least two dimensions further includes configuration of horizontal PMI report and vertical PMI report.

[00137] Example 75 includes the device of examples 72 to 74, wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report.

[00138] Example 76 includes the device of examples 72 to 75, wherein the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3 GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification.

[00139] Example 77 includes the device of examples 72 to 76 wherein the codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer.

[00140] Example 78 includes the device of examples 72 to 77, wherein a codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer.

[00141] FIG. 11 provides an example illustration of the wireless device, such as a user equipment (UE), a mobile station (MS), a mobile wireless device, a mobile

communication device, a tablet, a handset, or other type of wireless device. The wireless device can include one or more antennas configured to communicate with a node or transmission station, such as a base station (BS), an evolved Node B (eNodeB), a baseband unit (BBU), a remote radio head (RRH), a remote radio equipment (RRE), a relay station (RS), a radio equipment (RE), a remote radio unit (RRU), a central processing module (CPM), or other type of wireless wide area network (WWAN) access point. The wireless device can be configured to communicate using at least one wireless communication standard including 3GPP LTE, WiMAX, High Speed Packet Access (HSPA), Bluetooth, and Wi-Fi. The wireless device can communicate using separate antennas for each wireless communication standard or shared antennas for multiple wireless communication standards. The wireless device can communicate in a wireless local area network (WLAN), a wireless personal area network (WPAN), and/or a WWAN.

[00142] FIG. 11 also provides an illustration of a microphone and one or more speakers that can be used for audio input and output from the wireless device. The display screen can be a liquid crystal display (LCD) screen, or other type of display screen such as an organic light emitting diode (OLED) display. The display screen can be configured as a touch screen. The touch screen can use capacitive, resistive, or another type of touch screen technology. An application processor and a graphics processor can be coupled to internal memory to provide processing and display capabilities. The application processor, graphics processor, and internal memory can be a non-transitory storage medium. A non-volatile memory port can also be used to provide data input/output options to a user. The non- volatile memory port can also be used to expand the memory capabilities of the wireless device. A keyboard can be integrated with the wireless device or wirelessly connected to the wireless device to provide additional user input. A virtual keyboard can also be provided using the touch screen.

[00143] The wireless device in FIG. 12 can include radio frequency (RF)

circuitry, baseband circuitry, application circuitry, memory/storage, display,

camera, sensor, and/or input/output (I/O) interface. The application circuitry can include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor(s) can include any combination of general-purpose processors and dedicated processors (e.g., graphics processors, application processors, etc.). The processors can be coupled with memory/storage and configured to execute instructions stored in the memory/storage to enable various applications and/or operating systems running on the system. The memory/storage can be a non- volatile storage medium.

[00144] FIG. 12 illustrates, for one aspect, example components of a User Equipment (UE) device 1200. In some aspects, the UE device 1200 can include application circuitry 1202, baseband circuitry 1204, Radio Frequency (RF) circuitry 1206, front-end module (FEM) circuitry 1208 and one or more antennas 1210, coupled together at least as shown.

[00145] The application circuitry 1202 can include one or more application processors. For example, the application circuitry 1202 can include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor(s) can include any combination of general-purpose processors and dedicated processors (e.g., graphics processors, application processors, etc.). The processors can be coupled with and/or can include memory/storage and can be configured to execute instructions stored in the memory/storage to enable various applications and/or operating systems to run on the system. The memory/storage can be a storage medium (e.g., a non-volatile storage medium.)

[00146] The baseband circuitry 1204 can include circuitry such as, but not limited to, one or more single-core or multi-core processors. The baseband circuitry 1204 can include one or more baseband processors and/or control logic to process baseband signals received from a receive signal path of the RF circuitry 1206 and to generate baseband signals for a transmit signal path of the RF circuitry 1206. Baseband processing circuity 1204 can interface with the application circuitry 1202 for generation and processing of the baseband signals and for controlling operations of the RF circuitry 1206. For example, in some aspects, the baseband circuitry 1204 can include a second generation (2G) baseband processor 1204a, third generation (3G) baseband processor 1204b, fourth generation (4G) baseband processor 1204c, and/or other baseband processor(s) 1204d for other existing generations, generations in development or to be developed in the future (e.g., fifth generation (5G), 6G, etc.). The baseband circuitry 1204 (e.g., one or more of baseband processors 1204a-d) can handle various radio control functions that

enable communication with one or more radio networks via the RF circuitry 1206. The radio control functions can include, but are not limited to, signal

modulation/demodulation, encoding/decoding, radio frequency shifting, etc. In some aspects, modulation/demodulation circuitry of the baseband circuitry 1204 can include Fast-Fourier Transform (FFT), precoding, and/or constellation mapping/demapping functionality. In some aspects, encoding/decoding circuitry of the baseband circuitry

1204 can include convolution, tail-biting convolution, turbo, Viterbi, and/or Low Density Parity Check (LDPC) encoder/decoder functionality. Aspects of

modulation/demodulation and encoder/decoder functionality are not limited to these examples and can include other suitable functionality in other aspects.

[00147] In some aspects, the baseband circuitry 1204 can include elements of a protocol stack such as, for example, elements of an evolved universal terrestrial radio access network (EUTRAN) protocol including, for example, physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), and/or radio resource control (RRC) elements. A central processing unit (CPU) 1204e of the baseband circuitry 1204 can be configured to run elements of the protocol stack for signaling of the PHY, MAC, RLC, PDCP and/or RRC layers. In some aspects, the baseband circuitry can include one or more audio digital signal processor(s) (DSP) 1204f. The audio DSP(s) 1204f can be include elements for compression/decompression and echo cancellation and can include other suitable processing elements in other aspects. Components of the baseband circuitry can be suitably combined in a single chip, a single chipset, or disposed on a same circuit board in some aspects. In some aspects, some or all of the constituent components of the baseband circuitry 1204 and the application circuitry 1202 can be implemented together such as, for example, on a system on a chip (SOC). [00148] In some aspects, the baseband circuitry 1204 can provide for communication compatible with one or more radio technologies. For example, in some aspects, the baseband circuitry 1204 can support communication with an evolved universal terrestrial radio access network (EUTRAN) and/or other wireless metropolitan area networks (WMAN), a wireless local area network (WLAN), a wireless personal area network (WPAN). Aspects in which the baseband circuitry 1204 is configured to support radio communications of more than one wireless protocol can be referred to as multi- mode baseband circuitry.

[00149] RF circuitry 1206 can enable communication with wireless networks using modulated electromagnetic radiation through a non-solid medium. In various aspects, the RF circuitry 1206 can include switches, filters, amplifiers, etc. to facilitate the communication with the wireless network. RF circuitry 1206 can include a receive signal path which can include circuitry to down-convert RF signals received from the FEM circuitry 1208 and provide baseband signals to the baseband circuitry 1204. RF circuitry 1206 can also include a transmit signal path which can include circuitry to up-convert baseband signals provided by the baseband circuitry 1204 and provide RF output signals to the FEM circuitry 1208 for transmission.

[00150] In some aspects, the RF circuitry 1206 can include a receive signal path and a transmit signal path. The receive signal path of the RF circuitry 1206 can include mixer circuitry 1206a, amplifier circuitry 1206b and filter circuitry 1206c. The transmit signal path of the RF circuitry 1206 can include filter circuitry 1206c and mixer circuitry 1206a. RF circuitry 1206 can also include synthesizer circuitry 1206d for synthesizing a frequency for use by the mixer circuitry 1206a of the receive signal path and the transmit signal path. In some aspects, the mixer circuitry 1206a of the receive signal path can be configured to down-convert RF signals received from the FEM circuitry 1208 based on the synthesized frequency provided by synthesizer circuitry 1206d. The amplifier circuitry 1206b can be configured to amplify the down-converted signals and the filter circuitry 1206c can be a low-pass filter (LPF) or band-pass filter (BPF) configured to remove unwanted signals from the down-converted signals to generate output baseband signals. Output baseband signals can be provided to the baseband circuitry 1204 for further processing. In some aspects, the output baseband signals can be zero-frequency baseband signals, although this is not a requirement. In some aspects, mixer circuitry 1206a of the receive signal path can comprise passive mixers, although the scope of the aspects is not limited in this respect.

[00151] In some aspects, the mixer circuitry 1206a of the transmit signal path can be configured to up-convert input baseband signals based on the synthesized frequency provided by the synthesizer circuitry 1206d to generate RF output signals for the FEM circuitry 1208. The baseband signals can be provided by the baseband circuitry 1204 and can be filtered by filter circuitry 1206c. The filter circuitry 1206c can include a low-pass filter (LPF), although the scope of the aspects is not limited in this respect.

[00152] In some aspects, the mixer circuitry 1206a of the receive signal path and the mixer circuitry 1206a of the transmit signal path can include two or more mixers and can be arranged for quadrature downconversion and/or upconversion respectively. In some aspects, the mixer circuitry 1206a of the receive signal path and the mixer circuitry 1206a of the transmit signal path can include two or more mixers and can be arranged for image rejection (e.g., Hartley image rejection). In some aspects, the mixer circuitry 1206a of the receive signal path and the mixer circuitry 1206a can be arranged for direct

downconversion and/or direct upconversion, respectively. In some aspects, the mixer circuitry 1206a of the receive signal path and the mixer circuitry 1206a of the transmit signal path can be configured for super-heterodyne operation.

[00153] In some aspects, the output baseband signals and the input baseband signals can be analog baseband signals, although the scope of the aspects is not limited in this respect. In some alternate aspects, the output baseband signals and the input baseband signals can be digital baseband signals. In these alternate aspects, the RF circuitry 1206 can include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry and the baseband circuitry 1204 can include a digital baseband interface to communicate with the RF circuitry 1206.

[00154] In some dual-mode embodiments, a separate radio IC circuitry can be provided for processing signals for each spectrum, although the scope of the embodiments is not limited in this respect.

[00155] In some embodiments, the synthesizer circuitry 1206d can be a fractional-N synthesizer or a fractional N/N+l synthesizer, although the scope of the embodiments is not limited in this respect as other types of frequency synthesizers can be suitable. For example, synthesizer circuitry 1206d can be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer comprising a phase-locked loop with a frequency divider.

[00156] The synthesizer circuitry 1206d can be configured to synthesize an output frequency for use by the mixer circuitry 1206a of the RF circuitry 1206 based on a frequency input and a divider control input. In some embodiments, the synthesizer circuitry 1206d can be a fractional N/N+l synthesizer.

[00157] In some embodiments, frequency input can be provided by a voltage controlled oscillator (VCO), although that is not a requirement. Divider control input can be provided by either the baseband circuitry 1204 or the applications processor 1202 depending on the desired output frequency. In some embodiments, a divider control input (e.g., N) can be determined from a look-up table based on a channel indicated by the applications processor 1202.

[00158] Synthesizer circuitry 1206d of the RF circuitry 1206 can include a divider, a delay-locked loop (DLL), a multiplexer and a phase accumulator. In some embodiments, the divider can be a dual modulus divider (DMD) and the phase accumulator can be a digital phase accumulator (DPA). In some embodiments, the DMD can be configured to divide the input signal by either N or N+l (e.g., based on a carry out) to provide a fractional division ratio. In some example embodiments, the DLL can include a set of cascaded, tunable, delay elements, a phase detector, a charge pump and a D-type flip-flop. In these embodiments, the delay elements can be configured to break a VCO period up into Nd equal packets of phase, 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.

[00159] In some embodiments, synthesizer circuitry 1206d can be configured to generate a carrier frequency as the 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 quadrature generator and divider circuitry to generate multiple signals at the carrier frequency with multiple different phases with respect to each other. In some embodiments, the output frequency can be a LO frequency (fLO). In some embodiments, the RF circuitry 1206 can include an IQ/polar converter.

[00160] FEM circuitry 1208 can include a receive signal path which can include circuitry configured to operate on RF signals received from one or more antennas 1210, amplify the received signals and provide the amplified versions of the received signals to the RF circuitry 1206 for further processing. FEM circuitry 1208 can also include a transmit signal path which can include circuitry configured to amplify signals for transmission provided by the RF circuitry 1206 for transmission by one or more of the one or more antennas 1210.

[00161] In some embodiments, the FEM circuitry 1208 can include a TX/RX switch to switch between transmit mode and receive mode operation. The FEM circuitry can include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry can include a low-noise amplifier (LNA) to amplify received RF signals and provide the amplified received RF signals as an output (e.g., to the RF circuitry

1206). The transmit signal path of the FEM circuitry 1208 can include a power amplifier (PA) to amplify input RF signals (e.g., provided by RF circuitry 1206), and one or more filters to generate RF signals for subsequent transmission (e.g., by one or more of the one or more antennas 1210.

[00162] In some embodiments, the UE device 1200 can include additional elements such as, for example, memory/storage, display, camera, sensor, and/or input/output (I/O) interface.

[00163] FIG. 13 illustrates an example node 1310 (e.g., eNB) and an example wireless device 1320 (e.g., UE). The node can include a base station (BS), a Node B (NB), an evolved Node B (eNB), a baseband unit (BBU), a remote radio head (RRH), a remote radio equipment (RRE), a remote radio unit (RRU), or a central processing module (CPM). The node can include a node device 1312. The node device or the node can be configured to communicate with the wireless device. The node device can be configured to implement the technology described. The node device can include a processing module 1314 and a transceiver module 1316. In one aspect, the node device 1312 can include the transceiver module 1316 and the processing module 1314 forming a circuitry 1318 for the node 1310. In one aspect, the transceiver module 1316 and the processing module 1314 can form a circuitry of the node device 1312. Also, the wireless device 1320 and/or node 1310 may include circuitry, such as all or portions of circuitry described in FIG. 12, which can be arranged in a similar or different architectural framework, for implementing the technology described.

[00164] In some aspects, the circuitry of FIGS. 11-13 can be configured to perform one or more processes such as the processes of FIGS. 7-9.

[00165] The baseband circuitry can include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor(s) can include a

baseband processor. The baseband circuitry can handle various radio control functions that enable communication with one or more radio networks via the RF circuitry. The radio control functions can include, but are not limited to, signal modulation, encoding, decoding, radio frequency shifting, etc. In some aspects, the baseband circuitry can provide for communication compatible with one or more radio technologies. For example, in some aspects, the baseband circuitry can support communication with an evolved universal terrestrial radio access network (EUTRAN) and/or other wireless metropolitan area networks (WMAN), a wireless local area network (WLAN), a wireless personal area network (WPAN). Aspects in which the baseband circuitry can be configured to support radio communications of more than one wireless protocol can be referred to as multi-mode baseband circuitry.

[00166] In various aspects, baseband circuitry can include circuitry to operate with signals that are not strictly considered as being in a baseband frequency. For example, in some aspects, baseband circuitry can include circuitry to operate with signals having an intermediate frequency, which can be between a baseband frequency and a radio frequency.

[00167] RF circuitry can enable communication with wireless networks

using modulated electromagnetic radiation through a non-solid medium. In various aspects, the RF circuitry can include switches, filters, amplifiers, etc. to facilitate the communication with the wireless network.

[00168] In various aspects, RF circuitry can include circuitry to operate with signals that are not strictly considered as being in a radio frequency. For example, in some aspects, RF circuitry can include circuitry to operate with signals having an intermediate frequency, which can be between a baseband frequency and a radio frequency.

[00169] In various aspects, transmit circuitry, control circuitry, and/or receive circuitry discussed or described herein can be embodied in whole or in part in one or more of the RF circuitry, the baseband circuitry, and/or the application circuitry. As used herein, the term "circuitry" can refer to, be part of, or include an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group), and/or memory (shared, dedicated, or group) that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable hardware components that provide the described functionality. In some aspects, the electronic device circuitry can be implemented in, or functions associated with the circuitry can be implemented by, one or more software or firmware modules.

[00170] In some aspects, some or all of the constituent components of the

baseband circuitry, the application circuitry, and/or the memory/storage can be implemented together on a system on a chip (SOC).

[00171] Memory/storage can be used to load and store data and/or instructions, for example, for system. Memory/storage for one aspect can include any combination of suitable volatile memory (e.g., dynamic random access memory (DRAM)) and/or nonvolatile memory (e.g., Flash memory).

[00172] In various aspects, the I/O interface can include one or more user interfaces designed to enable user interaction with the system and/or peripheral

component interfaces designed to enable peripheral component interaction with the system. User interfaces can include, but are not limited to a physical keyboard or keypad, a touchpad, a speaker, a microphone, etc. Peripheral component interfaces can include, but are not limited to, a non-volatile memory port, a universal serial bus (USB) port, an audio jack, and a power supply interface. In various aspects, a display can include a display (e.g., a liquid crystal display, a touch screen display, etc.). In various aspects, the system can be a mobile computing device such as, but not limited to, a laptop computing device, a tablet computing device, a netbook, an ultrabook, a smartphone, etc. In various aspects, system can have more or less components, and/or different architectures.

[00173] In various aspects, the system can be a mobile computing device such as, but not limited to, a laptop computing device, a tablet computing device, a netbook, an ultrabook, a smartphone, etc. In various aspects, system can have more or less components, and/or different architectures. For example, in some aspects the RF circuitry and/or the baseband circuitry can be embodied in communication circuitry (not shown). The communication circuitry can include circuitry such as, but not limited to, one or more single-core or multi-core processors and logic circuits to provide signal processing techniques, for example, encoding, modulation, filtering, converting, amplifying, etc., suitable to the appropriate communication interface over which communications will take place. The communication circuitry can communicate over wireline, optical, or wireless

communication mediums. In aspects in which the system can be configured for wireless communication, the communication circuitry can include the RF circuitry and/or baseband circuitry to provide for communication compatible with one or more radio technologies. For example, in some aspects, the communication circuitry can

support communication with an evolved universal terrestrial radio access network (EUTRAN) and/or other wireless metropolitan area networks (WMAN), a wireless local area network (WLAN), a wireless personal area network (WPAN).

[00174] Aspects of the technology herein can be described as related to the third generation partnership project (3 GPP) long term evolution (LTE) or LTE-advanced (LTE- A) standards. For example, terms or entities such as eNodeB (eNodeB), mobility management entity (MME), user equipment (UE), etc. can be used that can be viewed as LTE-related terms or entities. However, in other aspects the technology can be used in or related to other wireless technologies such as the Institute of Electrical and Electronic Engineers (IEEE) 802.16 wireless technology (WiMax), IEEE 802.11 wireless technology (WiFi), various other wireless technologies such as global system for mobile

communications (GSM), enhanced data rates for GSM evolution (EDGE), GSM EDGE radio access network (GERAN), universal mobile telecommunications system (UMTS), UMTS terrestrial radio access network (UTRAN), or other 2G, 3G, 4G, 5G, etc.

technologies either already developed or to be developed. In those aspects, where LTE- related terms such as eNodeB, MME, UE, etc. are used, one or more entities or components can be used that can be considered to be equivalent or approximately equivalent to one or more of the LTE-based terms or entities.

[00175] Various techniques, or certain aspects or portions thereof, can take the form of program code (i.e., instructions) embodied in tangible media, such as floppy diskettes, CD-ROMs, hard drives, non-transitory computer readable storage medium, or any other machine-readable storage medium wherein, when the program code is loaded into and executed by a machine, such as a computer, the machine becomes an apparatus for practicing the various techniques. In the case of program code execution on

programmable computers, the computing device can include a processor, a storage medium readable by the processor (including volatile and non- volatile memory and/or storage elements), at least one input device, and at least one output device. The volatile and non-volatile memory and/or storage elements can be a RAM, EPROM, flash drive, optical drive, magnetic hard drive, or other medium for storing electronic data. The base station and mobile station can also include a transceiver module, a counter module, a processing module, and/or a clock module or timer module. One or more programs that can implement or utilize the various techniques described herein can use an application programming interface (API), reusable controls, and the like. Such programs can be implemented in a high level procedural or object oriented programming language to communicate with a computer system. However, the program(s) can be implemented in assembly or machine language, if desired. In any case, the language can be a compiled or interpreted language, and combined with hardware implementations.

[00176] It should be understood that many of the functional units described in this specification have been labeled as modules, in order to more particularly emphasize their implementation independence. For example, a module can be implemented as a hardware circuit comprising custom VLSI circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components. A module can also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices or the like.

[00177] Modules can also be implemented in software for execution by various types of processors. An identified module of executable code can, for instance, comprise one or more physical or logical blocks of computer instructions, which can, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified module need not be physically located together, but can comprise disparate instructions stored in different locations which, when joined logically together, comprise the module and achieve the stated purpose for the module.

[00178] Indeed, a module of executable code can be a single instruction, or many instructions, and can even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data can be identified and illustrated herein within modules, and can be embodied in any suitable form and organized within any suitable type of data structure. The operational data can be collected as a single data set, or can be distributed over different locations including over different storage devices, and can exist, at least partially, merely as electronic signals on a system or network. The modules can be passive or active, including agents operable to perform desired functions.

[00179] Reference throughout this specification to "an example" means that a particular feature, structure, or characteristic described in connection with the example is included in at least one aspect of the present disclosure. Thus, appearances of the phrases "in an example" in various places throughout this specification are not necessarily all referring to the same aspect.

[00180] As used herein, a plurality of items, structural elements, compositional elements, and/or materials can be presented in a common list for convenience. However, these lists should be construed as though each member of the list is individually identified as a separate and unique member. Thus, no individual member of such list should be construed as a de facto equivalent of any other member of the same list solely based on their presentation in a common group without indications to the contrary. In addition, various aspects and example of the present disclosure can be referred to herein along with alternatives for the various components thereof. It is understood that such aspects, examples, and alternatives are not to be construed as defacto equivalents of one another, but are to be considered as separate and autonomous representations of the present disclosure.

[00181] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more aspects. In the following description, numerous specific details are provided, such as examples of layouts, distances, network examples, etc., to provide a thorough understanding of aspects of the disclosure. One skilled in the relevant art will recognize, however, that the disclosure can be practiced without one or more of the specific details, or with other methods, components, layouts, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the disclosure.

[00182] While the forgoing examples are illustrative of the principles of the present disclosure in one or more particular applications, it will be apparent to those of ordinary skill in the art that numerous modifications in form, usage and details of implementation can be made without the exercise of inventive faculty, and without departing from the principles and concepts of the disclosure. Accordingly, it is not intended that the disclosure be limited, except as by the claims set forth below.

Claims

CLAIMS What is claimed is:

1. An apparatus of a user equipment (UE) operable to apply a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network, the apparatus comprising one or more processors and memory configured to: receive, at the UE, a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel;

receive, at the UE, the codebook subset restriction for a precoding matrix indicator (PMI) report corresponding to each of the at least two dimensions;

receive, at the UE, a CSI reporting request from an enhanced Node B (eNode B); and

calculate and report, from the UE, CSI according to the CSI reporting

configuration, the codebook subset restriction for each of the at least two dimensions, and the CSI reporting request received from the eNode B.

2. The apparatus of claim 1, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of PMI report and rank indicator (RI) report from a codebook subset restriction for the at least two dimensions.

3. The apparatus of claim 1 or 2, wherein the CSI reporting configuration for each of the at least two dimensions further includes configuration of horizontal PMI report and vertical PMI report.

4. The apparatus of claims 1, wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report.

5. The apparatus of claims 1, wherein the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3 GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification.

6. The apparatus of claims 1 or 4, wherein the codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer.

7. The apparatus of claims 1, wherein a codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer.

8. The apparatus of claims 1, wherein a codebook subset restriction for at least one dimension comprises a bitmap, wherein a different group of supported ranks include a same vertical PMI codebook subset restriction.

9. The apparatus of claims 1 or 8, wherein the same vertical PMI codebook subset restriction is defined for each different group of the supported ranks.

10. The apparatus of claim 9, wherein each different group of the supported ranks can include a first group including rank 1 and rank 2, a second group including rank 3 and rank 4, a third group including rank 5, rank 6, and rank 7, and a fourth group including rank 8.

11. An apparatus of an enhanced node B (eNode B) operable to use a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network, the apparatus comprising one or more processors and memory configured to: transmit to a user equipment (UE) a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel;

configure the codebook subset restriction for precoding matrix indicator (PMI) report for a first dimension of the at least two dimensions;

configure the codebook subset restriction for the PMI report for a second dimension of the at least two dimensions;

transmit to the UE, the codebook subset restriction for the PMI report

corresponding to the first dimension and the second dimension;

send to the UE a CSI reporting request; and receive from the UE, a CSI report according to the CSI reporting configuration, the codebook subset restriction for the first dimension and the second dimension, and the CSI reporting request.

12. The apparatus of claim 1 1, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of the PMI report and a rank indicator (RI) report from a codebook subset restriction.

13. The apparatus of claim 1 1, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of an horizontal PMI report and a vertical PMI report.

14. The apparatus of claims 1 1, wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report.

15. The apparatus of claims 11, wherein the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3 GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification.

16. The apparatus of claims 1 1, wherein the codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer.

17. The apparatus of claims 1 1, wherein the codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer.

18. The apparatus of claims 1 1, wherein the codebook subset restriction for at least one dimension comprises a bitmap, wherein a different group of supported ranks include the same vertical PMI codebook subset restriction.

19. The apparatus of claims 11 or 18, wherein the common vertical PMI codebook subset restriction is defined for each different group of the supported ranks comprising a first group including rank 1 and rank 2, a second group including rank 3 and rank 4, a third group including rank 5, rank 6, and rank 7, and a fourth group including rank 8, wherein each PMI restriction comprises Xj bits.

20. At least one non-transitory machine readable storage medium having instructions embodied thereon for performing a codebook subset restriction for full dimensional (FD) multiple-input multiple-output (MIMO) in a cellular network, the instructions when executed perform the following:

receive, at the UE, a channel state information (CSI) reporting configuration for at least two dimensions of a downlink channel;

receive, at the UE, a CSI reporting request from an enhanced Node B (eNode B);

calculate, from the UE, the CSI according to the CSI configuration, the codebook subset restriction for each of the at least two dimensions, and the CSI reporting request received from the eNode B; and

transmit the CSI to the eNode B.

21. The computer-readable storage medium of claim 20, wherein the CSI reporting configuration for each of the at least two dimensions further includes a configuration of PMI report and rank indicator (RI) report from a codebook subset restriction for the at least two dimensions.

22. The computer-readable storage medium of claim 20 or 21, wherein the CSI reporting configuration for each of the at least two dimensions further includes configuration of horizontal PMI report and vertical PMI report.

23. The computer-readable storage medium of claim 20, wherein the codebook subset restriction for each of the at least two dimensions comprises a bitmap, wherein each bit in the bitmap indicates when a PMI of a rank indicator (RI) in the codebook subset restriction is restricted from the PMI report.

24. The computer-readable storage medium of claim 22, wherein the codebook subset restriction for a first dimension of the at least two dimensions is in accordance to a third generation partnership project (3GPP) long term evolution advanced (LTE-A) release 12 (Rel-12) specification.

25. The computer-readable storage medium of claim 23 or 24 wherein the codebook subset restriction for a second dimension of the at least two dimensions comprises a bitmap, where Xi bits of the bitmap are allocated for independent restriction of a vertical beamforming codebook for an "ith" rank, wherein Xi is an integer.

26. The computer-readable storage medium of claims 20, wherein a codebook subset restriction for at least one dimension comprises a bitmap, where X bits of the bitmap are allocated for a common restriction of a vertical PMI codebook for each supported rank, wherein X is an integer.