WO2021066735A1

WO2021066735A1 - Csi-rs resource cdm group reinterpretation

Info

Publication number: WO2021066735A1
Application number: PCT/SE2020/050946
Authority: WO
Inventors: Sebastian FAXÉR; Siva Muruganathan; Mattias Frenne; Shiwei Gao; Robert Harrison; Claes Tidestav
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2019-10-04
Filing date: 2020-10-05
Publication date: 2021-04-08
Also published as: EP4042587A1

Abstract

A method by a network node for configuring a wireless device to report Channel State Information (CSI) includes computing an N-port Channel State Information-Reference Signal (CSI-RS) resource configuration. The N-port CSI-RS resource configuration includes a number of antenna ports, N, without Code Division Multiplexing (CDM), and N is greater than one. At least one antenna port associated with the N-port CSI-RS resource configuration overlaps with at least one antenna port group associated with an M-port CSI-RS resource configuration with CDM. The network node transmits CSI-RS over the N-port CSI-RS resource configuration to a wireless device for CSI computation and receives CSI from the wireless device according to the N-port CSI-RS resource configuration.

Description

CSI-RS RESOURCE CDM GROUP REINTERPRETATION

TECHNICAL FIELD

The present disclosure relates, in general, to wireless communications and, more particularly, systems and methods for Channel State Information-Reference Signal (CSI-RS) Code Division Multiplexing Group (CDM) reinterpretation.

BACKGROUND

Multi-antenna techniques can significantly increase the data rates and reliability of a wireless communication system. The performance is in particular improved if both the transmitter and the receiver are equipped with multiple antennas, which results in a multiple-input multiple-output (MIMO) communication channel. Such systems and/or related techniques are commonly referred to as MIMO.

The Third Generation Partnership Project (3 GPP) fifth generation (5G) new radio (NR) standard is currently evolving with enhanced MIMO support. A core component in NR is the support of MIMO antenna deployments and MIMO related techniques such as spatial multiplexing. The spatial multiplexing mode is aimed for high data rates in favorable channel conditions. FIGURE 1 illustrates an example of the spatial multiplexing operation. As illustrated in FIGURE 1, the information carrying symbol vector s is multiplied by an AT X r precoder matrix W , which distributes the transmit energy in a subspace of the AT (corresponding to AT antenna ports) dimensional vector space. The precoder matrix is typically selected from a codebook of possible precoder matrices, and typically indicated by means of a precoder matrix indicator (PMI), which specifies a unique precoder matrix in the codebook for a given number of symbol streams. The r symbols in s each correspond to a layer and r is referred to as the transmission rank. In this way, spatial multiplexing is achieved because multiple symbols can be transmitted simultaneously over the same time/frequency resource element (TFRE). The number of symbols r is typically adapted to suit the current channel properties. NR uses orthogonal frequency division multiplexing (OFDM) in the downlink (and discreet Fourier transform (DFT) precoded OFDM in the uplink) and hence the received N_R x 1 vector y_n for a certain TFRE on subcarrier n (or alternatively data TFRE number n) is thus modeled by y_n = H_nWs_n + e_n where e_n is a noise/interference vector obtained as realizations of a random process. The precoder W can be a wideband precoder, which is constant over frequency, or frequency selective.

The precoder matrix W is often chosen to match the characteristics of the N_RxN_T MIMO channel matrix H_n , resulting in channel dependent precoding. This is also commonly referred to as closed-loop precoding and essentially strives for focusing the transmit energy into a subspace which is strong in the sense of conveying much of the transmitted energy to the UE.

In closed-loop precoding for the NR downlink, the UE transmits, based on channel measurements in the forward link (downlink), recommendations to the gNB of a suitable precoder to use. The gNB configures the UE to provide feedback according to CSI-ReportConfig and may transmit CSI-RS and configure the UE to use measurements of CSI-RS to feed back recommended precoding matrices that the UE selects from a codebook. A single precoder that is supposed to cover a large bandwidth (wideband precoding) may be fed back. It may also be beneficial to match the frequency variations of the channel and instead feed back a frequency-selective precoding report, e.g. several precoders, one per subband. This is an example of the more general case of channel state information (CSI) feedback, which also encompasses feeding back other information than recommended precoders to assist the gNodeB in subsequent transmissions to the UE. Such other information may include channel quality indicators (CQIs) as well as transmission rank indicator (RI). In NR, CSI feedback can be either wideband, where one CSI is reported for the entire channel bandwidth, or frequency-selective, where one CSI is reported for each subband, which is defined as a number of contiguous resource blocks ranging between 4-32 PRBs depending on the band width part (BWP) size. Given the CSI feedback from the UE, the gNB determines the transmission parameters it wishes to use to transmit to the UE, including the precoding matrix, transmission rank, and modulation and coding scheme (MCS). The transmission parameters may differ from the recommendations the UE makes. The transmission rank, and thus the number of spatially multiplexed layers, is reflected in the number of columns of the precoder W . For efficient performance, it is important that a transmission rank that matches the channel properties is selected.

Particular embodiments presented later herein may be used with two- dimensional antenna arrays. Such antenna arrays may be (partly) described by the number of antenna elements corresponding to the horizontal dimension N_h, the number of antenna elements corresponding to the vertical dimension N_v and the number of dimensions corresponding to different polarizations N_p. The total number of antennas is thus N = N_hN_vN_p. As used herein, the concept of an antenna is non- limiting in the sense that it can refer to any virtualization (e.g., linear mapping) of the physical antenna elements. For example, pairs of physical sub-elements could be fed the same signal, and hence share the same virtualized antenna port.

FIGURE 2 illustrates an example of a 4x4 array with cross-polarized antenna elements. Specifically, FIGURE 2 illustrates a two-dimensional antenna array of cross-polarized antenna elements (N_P=2), with N_h=4 horizontal antenna elements and N_v=4 vertical antenna elements. Precoding may be interpreted as multiplying the signal with different beamforming weights for each antenna prior to transmission. A typical approach is to tailor the precoder to the antenna form factor, i.e. taking into account N_h, N_v and N_p when designing the precoder codebook.

For CSI measurement and feedback, CSI reference signals (CSI-RS) are defined. A CSI-RS is transmitted on each transmit antenna (or antenna port) and is used by a UE to measure the downlink channel between each of the transmit antenna ports and each of its receive antenna ports. The antenna ports are also referred to as CSI-RS ports. The supported number of antenna ports in NR are {1,2,4,8,12,16,24,32}. By measuring the received CSI-RS, a UE can estimate the channel that the CSI-RS is traversing, including the radio propagation channel and antenna gains. The CSI-RS for the above purpose is also referred to as Non-Zero Power (NZP) CSI-RS.

CSI-RS can be configured to be transmitted in certain resource elements (REs) in a slot and certain slots. FIGURE 3 illustrates an example of CSI-RS REs for 12 antenna ports, where IRE per resource block (RB) per port is shown.

FIGURE 3 illustrates an example of RE allocation for a 12-port CSI-RS in NR. An antenna port is equivalent to a reference signal resource that the UE uses to measure the channel. Thus, a gNB with two antennas could define two CSI-RS ports, where each port is a set of resource elements in the time frequency grid within a subframe or slot. The base station transmits each of these two reference signals from each of the two antennas so that the UE can measure the two radio channels and report channel state information back to the base station based on these measurements.

The sequence used for CSI-RS is r(m) and is defined by

where the pseudo-random sequence c(t) is defined in clause 5.2.1 of 3GPP TS 38.211. The pseudo-random sequence generator is initialised with

at the start of each OFDM symbol where is the slot number within a radio frame,

l is the OFDM symbol number within a slot, and n_ID equals the higher-layer parameter s cramblingID or sequenceGenerationConfig.

There are 18 different CSI-RS resource configurations in NR, where each have a specific number of ports X. See Table 1 below. The index k_i indicate which first subcarrier in the PRB that is used for mapping the CSI-RS sequence to resource elements, where the second subcarrier is k_i + 1. The set (k_i' k_i + 1) of subcarriers are denoted as a code division multiplexing (CDM) group for that particular OFDM symbol, where index i may be interpreted as the CDM group index. The index indicates the OFDM symbol within the slot. Thus, for example, the configuration given by row 4 is a X=4 port CSI-RS resource where two CDM groups are used, first starting at subcarrier k₀ and the second starting at subcarrier k₀ + 2 (= kq), both in the same OFDM symbol l_0. (Note that k_i and l_i are parameters signalled from gNB to UE by RRC signalling when configuring the CSI-RS resource).

Moreover, CSI-RS ports are numbered within a CDM group first and then across CDM groups. So, in this example, CSI-RS port 0 and 1 maps to the CDM group indicated by k₀ and port 2 and 3 maps to the CDM group indicated by k₀ + 2.

This is captured in the 3GPP specifications that the CSI-RS port indices p are numbered as

where s is the sequence index provided by Tables 7.4.1.5.3-2 to 7.4.1.5.3-5, below L E (1,2, 4, 8} is the CDM group size, and N is the number of CSI-RS ports. The CDM group index j is given in Table 1 and corresponds to the time/frequency locations for a given row of the table. The CDM groups are numbered in order of

increasing frequency domain allocation first and then increasing time domain allocation. For some rows, more than two CDM groups are used and they can be individually mapped to subcarriers, an example is row 10 where three CDM group indices k₀, k_i and k₂ are used in one and the same symbol given by the RRC configured parameter l_0.

A CDM group can refer to a set of 2, 4 or 8 antenna ports, where the set of 2 antenna ports occurs when only CDM in frequency-domain (FD-CDM) over two adjacent subcarriers is considered. Table 1 includes CSI-RS locations within a slot.

TABLE 1

In more strict mathematical terminology, the mapping of the sequence r(m) onto resource-elements for CSI-RS antenna port p can be described by:

For the different CDM types, the following CDM weights are used, where w(k', /') = W_f(k') - w_t(l' ) corresponds to the resulting CDM weights formed by the multiplication of the frequency and time-domain CDM weight.

Table 2 summarizes the sequences and for cdm-Type equal to

'no CDM'.

TABLE 2

Table 3 summarizes the sequences w_f(k') and w_t(l') for cdm-Type equal to 'FD-CDM2'.

TABLE 3

Table 4 summarizes the sequences w_f(k') and w_t(l') for cdm-Type equal to 'CDM4'.

TABLE 4

Table 5 summarizes the sequences w_f(k') and w_t(l') for cdm-Type equal to

'CDM8'.

TABLE 5

A common type of precoding is to use a DFT-precoder, where the precoder vector used to precode a single-layer transmission using a single-polarized uniform linear array (ULA) with N antennas is defined as

where k = 0,1, ... QN — 1 is the precoder index and Q is an integer oversampling factor. A corresponding precoder vector for a two-dimensional uniform planar array (UPA) can be created by taking the Kronecker product of two precoder vectors as w_2D(k, l ) = w_1D(k)Θw_1D(l). Extending the precoder for a dual -polarized UPA may then be done as

where is a co-phasing factor that may for instance be selected from QPSK alphabet

A precoder matrix W_{2D DP} for multi-layer transmission may be created by appending columns ofDFT precoder vectors as

where R is the number of transmission layers, i.e. the transmission rank. In a common special case for a rank-2 DFT precoder, k₁ = k₂ = k and l = l₂ = l, meaning that

Such DFT-based precoders are used, for example, in NR Type I CSI feedback. The NR codebook thus assumes an antenna port indexing which maps ports first along the second dimension (identified by the index /, which may be the vertical dimension), then the first dimension (identified by the index k , which may be the horizontal dimension), and then the polarization dimension.

In NR, a UE can be configured with multiple CSI report settings and multiple CSI-RS resource settings. Each resource setting can contain multiple resource sets, and each resource set can contain up to 8 CSI-RS resources. For each CSI report setting, a UE feeds back a CSI report, either periodically or aperiodically (triggered by the network).

Each CSI report setting contains at least the following information:

• A CSI-RS resource set for channel measurement

• An IMR resource set for interference measurement

• Optionally, a CSI-RS resource set for interference measurement

• Time-domain behavior, i.e. periodic, semi-persistent, or aperiodic reporting

• Frequency granularity, i.e. wideband or subband

• CSI parameters to be reported such as RI, PMI, CQI, and CSI-RS resource indicator (CRI) in case of multiple CSI-RS resources in a resource set • Codebook types, i.e. type I or II, and eventual codebook subset restriction

• Measurement restriction enabled or disabled

• Subband size. One out of two possible subband sizes is indicated, the value range for a subband size depends on the configured bandwidth of the downlink bandwidth part (BWP). One CQI/PMI (if configured for subband reporting) is fed back per subband.

When the CSI-RS resource set in a CSI report setting contains multiple CSI-RS resources, one of the CSI-RS resources is selected by a UE and a CSI-RS resource indicator (CRI) is also reported by the UE to indicate to the gNB about the selected CSI-RS resource in the resource set, together with RI, PMI and CQI associated with the selected CSI-RS resource. The network may then transmit the different CSI-RS resources using different MIMO precoders or by using different beam directions

For aperiodic CSI reporting in NR, more than one CSI report settings, each with a different CSI-RS resource set for channel measurement and/or different resource set for interference measurement can be configured and triggered at the same time, i.e. with a single trigger command in the downlink control channel from the gNB to the UE. In this case, multiple CSI reports are measured, computed, aggregated and sent from the UE to the gNB in a single PUSCH message. As a general classification, NR categorizes a CSI Report Setting into wideband and subband frequency -granularity as follows:

• wideband PMI/CQI reporting, beam reporting, hybrid CSI report, semiopen loop reporting and non-PMI feedback (with wideband CQI) is classified as wideband frequency-granularity CSI, whereas · the other configurations of a CSI Report Setting is classified as having a subband frequency-granularity.

Only CSI Report Settings with wideband frequency-granularity is allowed to be periodically reported on short PUCCH. There currently exist certain challenges. For example, a practical cellular system must be able to serve and handle UEs with different capabilities, such as different capabilities in the number of supported CSI-RS ports within a resource. As a particular example, regular UEs may support 32 CSI-RS ports while lower complexity UEs may only support 8 CSI-RS ports. Thus, to serve the two UE complexity categories simultaneously, at least two CSI-RS resources (one 32 port resource and one 8 port resource) will be used, which results in large CSI-RS overhead. Furthermore, because an 8 port CSI-RS resource transmitted from a 32 port antenna array can only probe in a subset of channel directions, the gNB may need to use multiple 8 port CSI-RS resources to serve the lower complexity UEs, which results in even larger overhead. One such lower complexity UE category is described in NR Rel-17 and referred to as “NR Light. ”

SUMMARY Certain aspects of the present disclosure and their embodiments may provide solutions to these or other challenges. Particular embodiments facilitate reuse of a single Channel State Information-Reference Signal (CSI-RS) resource with M antenna ports for a user equipment (UE) or other wireless device that is only able to calculate Channel State Information (CSI) for N<M antenna ports using a new non-Code Division Multiplexing (CDM) CSI-RS resource overlapping on Resource Elements (REs) of an existing CDM CSI-RS resource.

According to certain embodiments, a method for computing CSI by a wireless device includes obtaining an N-port CSI-RS resource configuration. The N-port CSI- RS resource configuration includes a number of antenna ports, N, without CDM, and N is greater than one. The wireless device computes CSI based on the N-port CSI-RS resource configuration and reports the CSI to a network node.

According to certain embodiments, a wireless device for computing CSI includes processing circuitry configured to obtain an N-port CSI-RS resource configuration. The N-port CSI-RS resource configuration includes a number of antenna ports, N, without CDM, and N is greater than one. The processing circuitry is configured to compute CSI based on the N-port CSI-RS resource configuration and to report the CSI to a network node.

According to certain embodiments, a method by a network node for configuring a wireless device to report CSI includes computing an N-port CSI-RS resource configuration. The N-port CSI-RS resource configuration includes a number of antenna ports, N, without CDM, and N is greater than one. At least one antenna port associated with the N-port CSI-RS resource configuration overlaps with at least one antenna port group associated with an M-port CSI-RS resource configuration with CDM. The network node transmits CSI-RS over the N-port CSI-RS resource configuration to the wireless device for CSI computation and receives CSI from the wireless device according to the N-port CSI-RS resource configuration.

According to certain embodiments, a network node for configuring a wireless device to report CSI includes processing circuitry configured to compute an N-port CSI-RS resource configuration. The N-port CSI-RS resource configuration includes a number of antenna ports, N, without CDM, and N is greater than one. At least one antenna port associated with the N-port CSI-RS resource configuration overlaps with at least one antenna port group associated with an M-port CSI-RS resource configuration with CDM. The processing circuitry is configured to transmit CSI-RS over the N-port CSI-RS resource configuration to the wireless device for CSI computation and receive CSI from the wireless device according to the N-port CSI-RS resource configuration.

There are, proposed herein, various embodiments which address one or more of the issues disclosed herein. Certain embodiments may provide one or more of the following technical advantages. For example, particular embodiments use a single CSI-RS resource for both regular and low-complexity UEs, resulting in lower CSI-RS overhead and thus improved Physical Downlink Shared Channel (PDSCH) throughput.

Other advantages may be readily apparent to one having skill in the art. Certain embodiments may have none, some, or all of the recited advantages.

BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the disclosed embodiments and their features and advantages, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:

FIGURE 1 illustrates an example of the spatial multiplexing operation; FIGURE 2 illustrates an example of a 4x4 array with cross-polarized antenna elements;

FIGURE 3 illustrates an example of Channel State Information-Reference Signal (CSI-RS) Resource Elements (REs) for 12 antenna ports, where IRE per resource block (RB) per port is shown; FIGURE 4 illustrates certain limitations of legacy CSI-RS resources, according to certain embodiments;

FIGURE 5 illustrates a mapping of antenna port to REs of a Code Division Multiplex (CDM) group, according to certain embodiments;

FIGURE 6 illustrates an example of interpreting the RE of a CDMed CSI-RS resource as a new non-CDMed CSI-RS port, according to certain embodiments;

FIGURE 7 illustrates example beam patterns formed by CDM codes, according to certain embodiments;

FIGURE 8 illustrates an example wireless network, according to certain embodiments; FIGURE 9 illustrates an example network node, according to certain embodiments;

FIGURE 10 illustrates an example wireless device, according to certain embodiments;

FIGURE 11 illustrate an example user equipment, according to certain embodiments;

FIGURE 12 illustrates a virtualization environment in which functions implemented by some embodiments may be virtualized, according to certain embodiments;

FIGURE 13 illustrates a telecommunication network connected via an intermediate network to a host computer, according to certain embodiments; FIGURE 14 illustrates a generalized block diagram of a host computer communicating via a base station with a user equipment over a partially wireless connection, according to certain embodiments;

FIGURE 15 illustrates a method implemented in a communication system, according to one embodiment;

FIGURE 16 illustrates another method implemented in a communication system, according to one embodiment;

FIGURE 17 illustrates another method implemented in a communication system, according to one embodiment; FIGURE 18 illustrates another method implemented in a communication system, according to one embodiment;

FIGURE 19 illustrates an example method by a network node, according to certain embodiments;

FIGURE 20 illustrates an example virtualization apparatus, according to certain embodiments;

FIGURE 21 illustrates an example method by a wireless device, according to certain embodiments;

FIGURE 22 illustrates another example virtualization apparatus, according to certain embodiments; FIGURE 23 illustrates another example method by a network node, according to certain embodiments; and

FIGURE 24 illustrates another example virtualization apparatus, according to certain embodiments.

DETAILED DESCRIPTION

Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Other embodiments, however, are contained within the scope of the subject matter disclosed herein, the disclosed subject matter should not be construed as limited to only the embodiments set forth herein; rather, these embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

Generally, all terms used herein are to be interpreted according to their ordinary meaning in the relevant technical field, unless a different meaning is clearly given and/or is implied from the context in which it is used. All references to a/an/the element, apparatus, component, means, step, etc. are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. The steps of any methods disclosed herein do not have to be performed in the exact order disclosed, unless a step is explicitly described as following or preceding another step and/or where it is implicit that a step must follow or precede another step. Any feature of any of the embodiments disclosed herein may be applied to any other embodiment, wherever appropriate. Likewise, any advantage of any of the embodiments may apply to any other embodiments, and vice versa. Other objectives, features and advantages of the enclosed embodiments will be apparent from the following description.

Certain embodiments disclosed herein facilitate reuse of a single Channel State Information-Reference Signal (CSI-RS) resource with M antenna ports for a user equipment (UE) or other wireless device that is only able to calculate Channel State Information (CSI) for N<M antenna ports using a new non-Code Division Multiplexing (CDM) CSI-RS resource overlapping on Resource Elements (REs) of an existing CDM CSI-RS resource.

For example, a network node such as a gNodeB (gNB) may transmit a legacy M-port CSI-RS resource which comprises CDMed antenna port groups and configures one subset of UEs to measure on the M-port CSI-RS resource, but configures another subset of UEs to measure on a newly defined N-port CSI-RS resource without CDM, which overlaps with one CDM group of the M-port CSI-RS resource, and where N < M. A UE may be configured with a CSI-RS resource which contains N CSI-RS ports and which does not use CDM, and where the CSI-RS resource has the characteristic that it may overlap with another M-port CSI-RS resource which uses CDM-M.

It is beneficial for the gNB to be able to reuse a larger, M ports, CSI-RS resource for measurement for a UE which only is capable of calculating CSI for and/or measuring on a smaller number N antenna ports to reduce the amount of CSI-RS resources/ports transmitted and thereby reduce the overhead on the physical layer, which leaves more resources for physical downlink shared channel (PDSCH) transmission. Particular examples described herein may use the special case where M=32 ports and N=8 ports, but the embodiments described herein apply to other values of M and N.

Particular embodiments include a new N-port CSI-RS resource definition, which is configured by the gNB to the UE, which has the characteristic that it can overlap with an existing, legacy, M-port CSI-RS resource (which may have been configured by the gNB to another UE or wireless device) and that the UE can still derive meaningful CSI. This is not possible with existing CSI-RS resource definitions.

While it is possible to configure, for example, an 8-port resource (e.g., row 8 of Table 1) overlapping with a 32 port resource (row 17 of Table 1), the UE will not report meaningful CSI. FIGURE 4 illustrates the limitations of legacy CSI-RS resources, according to certain embodiments. The antenna mapping of 32 port CSI- RS resource is illustrated to the left and the antenna mapping of an 8-port CSI-RS resource is illustrated the right.

Assume that the gNB uses a (N₁,N₂ ^') = (4,4) antenna port configuration for the 32-port CSI-RS. Each of the 8 CDM-groups ( k₀, l₀ ), (k₁, l₀), (k₂, l₀), (k₃, l₀), (k₀,l₁), (k₁, l₁), (k₂, l₁), (k₃, l₁) of CSI-RS configuration 17 corresponds to one column of a polarization of the antenna array. So while the gNB can configure the overlapping CSI-RS configuration 8, which is identified by CDM groups ( k₀, l₀ ), (k₁,l₀) (note that the values k₀, k₁, l₀ configured to the 8-port CSI-RS resource can be different than the k₀, k₁, l₀ values configured to the 32-port CSI-Rs resource, so it is for instance possible to configure it is constrained in such a

way that only two antenna columns of the same polarization can be measured by the UE. Not only cannot the full dual-polarized antenna array be sounded, which limits the channel subspace being observable by the UE, the corresponding 8-port antenna codebooks assume a dual-polarized port layout, so applying the 8-port codebook to a single-polarized 4x2 port layout will lead to performance loss. In addition, because the 8-port CSI-RS is only transmitted from a subset of the array antennas, only a subset of the available transmit power is used and the CSI-RS coverage is reduced.

Therefore, it is beneficial for an overlapping CSI-RS resource definition to facilitate CSI calculation corresponding to the full antenna array dimension (so that all available beamforming gain can be utilized) and enable a precoder codebook, which captures the actual effective port layout, to be applied. This enables all of the available CSI-RS transmit power to be captured in the measurement.

Particular embodiments include a non-CDMed CSI-RS resource overlapping on REs of existing CDMed CSI-RS resource. One limitation with the alternative methods is that they may only achieve complexity reduction in the PMI calculation, the UE still needs to perform measurement of all the M ports of the parent resource. It would be beneficial to apply the complexity reduction on the CSI-RS measurement as well, but in such a way that the CSI-RS can capture the full array dimensions and power.

Particular embodiments reinterpret the CDM weights of the legacy M-port CSI-RS resource as virtualization (or beamforming) weights of a new CSI-RS resource. As described above, the CDM weights w(k',l' ) = w_f(k') · w_t(l') of a CDM group is multiplied onto the reference signal sequence r(m) before being mapped to the time-frequency grid. For the example case of CDM-4, the following four sequences are applied to the REs n = 2k + l' , l' ∈ {0,1}, k' ∈ {0,1} for each group of 4 subsequent antenna ports: w₀ = [1111] w₁ = [ 11-1-1] w₂ = [1-11-1] w₃ = [ 1-1-11] This means that the signal received on a certain CSI-RS RE (k',l') can be expressed as

where r(m) is the CSI-RS sequence, w_p (k' , /') is the CDM weight for port p and H(p) is the channel for port p. For a regular UE measuring all the M CSI-RS ports, it measures the channel on all REs of the CDM group and applies CDM de-spreading to recover the channel of each individual port. However, a low complexity UE measures a single RE of the CDM group and considers that as a new antenna port, whereby the effect is similar as antenna virtualization.

FIGURE 5 illustrates an example mapping 20 of antenna ports to REs of a CDM group, according to certain embodiments. Because antenna ports within a CDM group are subsequent antenna ports according to the antenna port numbering, these typically correspond to adjacent vertical antennas of the same polarization, as is illustrated in FIGURE 5.

FIGURE 6 illustrates an example 30 of interpreting the RE of a CDMed CSI- RS resource as a new non-CDMed CSI-RS port, according to certain embodiments. For a low complexity UE that measures on a single RE of the CDM group, the measured signal is the sum of the per-antenna channels weighted with the CDM code weights corresponding to that RE, as is illustrated in FIGURE 6.

Depending on which RE of the CDM group the UE is configured to measure, different CDM codes are used, which correspond to different beam patterns (i.e., antenna virtualization). FIGURE 7 illustrates an example 40 of possible resulting beam patterns of the CDM-4 codes, according to certain embodiments.

As illustrated, two of the CDM codes result in DFT vectors ([1 1 1 1] and [1 - 1 1 -1], which corresponds to steering the beam towards θ = 90° and θ = 130° respectively (assuming 0.8 wavelength port distance)) while the remaining two results in non-DFT beams. Depending on the UEs position in elevation (which could be determined from other means such as UL signals), the gNB could configure the UE to measure different REs of the CDM group and thus achieve a different vertical beam. From a UE perspective, it does not need to be aware of that the N-port CSI-RS resource is overlapping with an M-port CSI-RS resource, it is simply configured to measure CSI-RS on a N-port CSI-RS resource which does not apply CDM (and where the REs of that resource overlap with one of the CDMed REs of the M-port resource, but that is transparent to the UE). This can be achieved by using a new CSI-RS configuration in the specification. For example, if the gNB desires to use CSI-RS configuration 17 for the M-port CSI-RS resource, then the following new CSI-RS resource(s) can be defined as is shown in Table 6.

TABLE 6

Where Δ₁ ∈ {0,1} ,Δ₂ ∈ {0,1} is a configuration parameter indicating the RE offset (i.e. which RE offset (k',l') within the CDM group of CSI-RS configuration 17 the new CSI-RS resource overlaps with).

FIGURE 8 illustrates an example wireless network in accordance with some embodiments. Although the subject matter described herein may be implemented in any appropriate type of system using any suitable components, the embodiments disclosed herein are described in relation to a wireless network, such as the example wireless network illustrated in FIGURE 8. For simplicity, the wireless network of FIGURE 8 only depicts network 106, network nodes 160 and WDs 110. In practice, a wireless network may further include any additional elements suitable to support communication between wireless devices or between a wireless device and another communication device, such as a landline telephone, a service provider, or any other network node or end device. Of the illustrated components, network node 160 and wireless device (WD) 110 are depicted with additional detail. The wireless network may provide communication and other types of services to one or more wireless devices to facilitate the wireless devices’ access to and/or use of the services provided by, or via, the wireless network.

The wireless network may comprise and/or interface with any type of communication, telecommunication, data, cellular, and/or radio network or other similar type of system. In some embodiments, the wireless network may be configured to operate according to specific standards or other types of predefined rules or procedures. Thus, particular embodiments of the wireless network may implement communication standards, such as Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), Long Term Evolution (LTE), and/or other suitable 2G, 3G, 4G, or 5G standards; wireless local area network (WLAN) standards, such as the IEEE 802.11 standards; and/or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave and/or ZigBee standards.

Network 106 may comprise one or more backhaul networks, core networks, IP networks, public switched telephone networks (PSTNs), packet data networks, optical networks, wide-area networks (WANs), local area networks (LANs), wireless local area networks (WLANs), wired networks, wireless networks, metropolitan area networks, and other networks to enable communication between devices.

Network node 160 and WD 110 comprise various components described in more detail below. These components work together in order to provide network node and/or wireless device functionality, such as providing wireless connections in a wireless network. In different embodiments, the wireless network may comprise any number of wired or wireless networks, network nodes, base stations, controllers, wireless devices, relay stations, and/or any other components or systems that may facilitate or participate in the communication of data and/or signals whether via wired or wireless connections.

FIGURE 9 illustrates an example network node 160, according to certain embodiments. As used herein, network node refers to equipment capable, configured, arranged and/or operable to communicate directly or indirectly with a wireless device and/or with other network nodes or equipment in the wireless network to enable and/or provide wireless access to the wireless device and/or to perform other functions (e.g., administration) in the wireless network. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)). Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and may then also be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units and/or remote radio units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS). Yet further examples of network nodes include multi-standard radio (MSR) equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi-cell/multicast coordination entities (MCEs), core network nodes (e.g., MSCs, MMEs), O&M nodes, OSS nodes, SON nodes, positioning nodes (e.g., E-SMLCs), and/or MDTs. As another example, a network node may be a virtual network node as described in more detail below. More generally, however, network nodes may represent any suitable device (or group of devices) capable, configured, arranged, and/or operable to enable and/or provide a wireless device with access to the wireless network or to provide some service to a wireless device that has accessed the wireless network.

In FIGURE 9, network node 160 includes processing circuitry 170, device readable medium 180, interface 190, auxiliary equipment 184, power source 186, power circuitry 187, and antenna 162. Although network node 160 illustrated in the example wireless network of FIGURE 9 may represent a device that includes the illustrated combination of hardware components, other embodiments may comprise network nodes with different combinations of components. It is to be understood that a network node comprises any suitable combination of hardware and/or software needed to perform the tasks, features, functions and methods disclosed herein. Moreover, while the components of network node 160 are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, a network node may comprise multiple different physical components that make up a single illustrated component (e.g., device readable medium 180 may comprise multiple separate hard drives as well as multiple RAM modules).

Similarly, network node 160 may be composed of multiple physically separate components (e.g., a NodeB component and a RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components. In certain scenarios in which network node 160 comprises multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeB's. In such a scenario, each unique NodeB and RNC pair may in some instances be considered a single separate network node. In some embodiments, network node 160 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate device readable medium 180 for the different RATs) and some components may be reused (e.g., the same antenna 162 may be shared by the RATs). Network node 160 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 160, such as, for example, GSM, WCDMA, LTE, NR, WiFi, or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network node 160.

Processing circuitry 170 is configured to perform any determining, calculating, or similar operations (e.g., certain obtaining operations) described herein as being provided by a network node. These operations performed by processing circuitry 170 may include processing information obtained by processing circuitry 170 by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and/or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Processing circuitry 170 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide, either alone or in conjunction with other network node 160 components, such as device readable medium 180, network node 160 functionality. For example, processing circuitry 170 may execute instructions stored in device readable medium 180 or in memory within processing circuitry 170. Such functionality may include providing any of the various wireless features, functions, or benefits discussed herein. In some embodiments, processing circuitry 170 may include a system on a chip (SOC). In some embodiments, processing circuitry 170 may include one or more of radio frequency (RF) transceiver circuitry 172 and baseband processing circuitry 174. In some embodiments, radio frequency (RF) transceiver circuitry 172 and baseband processing circuitry 174 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry 172 and baseband processing circuitry 174 may be on the same chip or set of chips, boards, or units

In certain embodiments, some or all of the functionality described herein as being provided by a network node, base station, eNB or other such network device may be performed by processing circuitry 170 executing instructions stored on device readable medium 180 or memory within processing circuitry 170. In alternative embodiments, some or all of the functionality may be provided by processing circuitry 170 without executing instructions stored on a separate or discrete device readable medium, such as in a hard-wired manner. In any of those embodiments, whether executing instructions stored on a device readable storage medium or not, processing circuitry 170 can be configured to perform the described functionality. The benefits provided by such functionality are not limited to processing circuitry 170 alone or to other components of network node 160, but are enjoyed by network node 160 as a whole, and/or by end users and the wireless network generally. Device readable medium 180 may comprise any form of volatile or nonvolatile computer readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device readable and/or computer-executable memory devices that store information, data, and/or instructions that may be used by processing circuitry 170. Device readable medium 180 may store any suitable instructions, data or information, including a computer program, software, an application including one or more of logic, rules, code, tables, etc. and/or other instructions capable of being executed by processing circuitry 170 and, utilized by network node 160. Device readable medium 180 may be used to store any calculations made by processing circuitry 170 and/or any data received via interface 190. In some embodiments, processing circuitry 170 and device readable medium 180 may be considered to be integrated.

Interface 190 is used in the wired or wireless communication of signalling and/or data between network node 160, network 106, and/or WDs 110. As illustrated, interface 190 comprises port(s)/terminal(s) 194 to send and receive data, for example to and from network 106 over a wired connection. Interface 190 also includes radio front end circuitry 192 that may be coupled to, or in certain embodiments a part of, antenna 162. Radio front end circuitry 192 comprises filters 198 and amplifiers 196. Radio front end circuitry 192 may be connected to antenna 162 and processing circuitry 170. Radio front end circuitry may be configured to condition signals communicated between antenna 162 and processing circuitry 170. Radio front end circuitry 192 may receive digital data that is to be sent out to other network nodes or WDs via a wireless connection. Radio front end circuitry 192 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 198 and/or amplifiers 196. The radio signal may then be transmitted via antenna 162. Similarly, when receiving data, antenna 162 may collect radio signals which are then converted into digital data by radio front end circuitry 192. The digital data may be passed to processing circuitry 170. In other embodiments, the interface may comprise different components and/or different combinations of components.

In certain alternative embodiments, network node 160 may not include separate radio front end circuitry 192, instead, processing circuitry 170 may comprise radio front end circuitry and may be connected to antenna 162 without separate radio front end circuitry 192. Similarly, in some embodiments, all or some of RF transceiver circuitry 172 may be considered a part of interface 190. In still other embodiments, interface 190 may include one or more ports or terminals 194, radio front end circuitry 192, and RF transceiver circuitry 172, as part of a radio unit (not shown), and interface 190 may communicate with baseband processing circuitry 174, which is part of a digital unit (not shown). Antenna 162 may include one or more antennas, or antenna arrays, configured to send and/or receive wireless signals. Antenna 162 may be coupled to radio front end circuitry 190 and may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. In some embodiments, antenna 162 may comprise one or more omni-directional, sector or panel antennas operable to transmit/receive radio signals between, for example, 2 GHz and 66 GHz. An omni-directional antenna may be used to transmit/receive radio signals in any direction, a sector antenna may be used to transmit/receive radio signals from devices within a particular area, and a panel antenna may be a line of sight antenna used to transmit/receive radio signals in a relatively straight line. In some instances, the use of more than one antenna may be referred to as MIMO. In certain embodiments, antenna 162 may be separate from network node 160 and may be connectable to network node 160 through an interface or port.

Antenna 162, interface 190, and/or processing circuitry 170 may be configured to perform any receiving operations and/or certain obtaining operations described herein as being performed by a network node. Any information, data and/or signals may be received from a wireless device, another network node and/or any other network equipment. Similarly, antenna 162, interface 190, and/or processing circuitry 170 may be configured to perform any transmitting operations described herein as being performed by a network node. Any information, data and/or signals may be transmitted to a wireless device, another network node and/or any other network equipment.

Power circuitry 187 may comprise, or be coupled to, power management circuitry and is configured to supply the components of network node 160 with power for performing the functionality described herein. Power circuitry 187 may receive power from power source 186. Power source 186 and/or power circuitry 187 may be configured to provide power to the various components of network node 160 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). Power source 186 may either be included in, or external to, power circuitry 187 and/or network node 160. For example, network node 160 may be connectable to an external power source (e.g., an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry 187. As a further example, power source 186 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry 187. The battery may provide backup power should the external power source fail. Other types of power sources, such as photovoltaic devices, may also be used.

Alternative embodiments of network node 160 may include additional components beyond those shown in FIGURE 9 that may be responsible for providing certain aspects of the network node’s functionality, including any of the functionality described herein and/or any functionality necessary to support the subject matter described herein. For example, network node 160 may include user interface equipment to allow input of information into network node 160 and to allow output of information from network node 160. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for network node 160. FIGURE 10 illustrates an example wireless device (WD) 110, according to certain embodiments. As used herein, WD refers to a device capable, configured, arranged and/or operable to communicate wirelessly with network nodes and/or other wireless devices. Unless otherwise noted, the term WD may be used interchangeably herein with user equipment (UE). Communicating wirelessly may involve transmitting and/or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and/or other types of signals suitable for conveying information through air. In some embodiments, a WD may be configured to transmit and/or receive information without direct human interaction. For instance, a WD may be designed to transmit information to a network on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the network. Examples of a WD include, but are not limited to, a smart phone, a mobile phone, a cell phone, a voice over IP (VoIP) phone, a wireless local loop phone, a desktop computer, a personal digital assistant (PDA), a wireless cameras, a gaming console or device, a music storage device, a playback appliance, a wearable terminal device, a wireless endpoint, a mobile station, a tablet, a laptop, a laptop-embedded equipment (LEE), a laptop-mounted equipment (LME), a smart device, a wireless customer-premise equipment (CPE), a vehicle-mounted wireless terminal device, etc. A WD may support device-to-device (D2D) communication, for example by implementing a 3 GPP standard for sidelink communication, vehicle-to-vehicle (V2V), vehicle-to- infrastructure (V2I), vehicle-to-everything (V2X) and may in this case be referred to as a D2D communication device. As yet another specific example, in an Internet of Things (IoT) scenario, a WD may represent a machine or other device that performs monitoring and/or measurements, and transmits the results of such monitoring and/or measurements to another WD and/or a network node. The WD may in this case be a machine-to-machine (M2M) device, which may in a 3 GPP context be referred to as an MTC device. As one particular example, the WD may be a UE implementing the 3GPP narrow band internet of things (NB-IoT) standard. Particular examples of such machines or devices are sensors, metering devices such as power meters, industrial machinery, or home or personal appliances (e.g. refrigerators, televisions, etc.) personal wearables (e.g., watches, fitness trackers, etc.). In other scenarios, a WD may represent a vehicle or other equipment that is capable of monitoring and/or reporting on its operational status or other functions associated with its operation. A WD as described above may represent the endpoint of a wireless connection, in which case the device may be referred to as a wireless terminal. Furthermore, a WD as described above may be mobile, in which case it may also be referred to as a mobile device or a mobile terminal.

As illustrated, wireless device 110 includes antenna 111, interface 114, processing circuitry 120, device readable medium 130, user interface equipment 132, auxiliary equipment 134, power source 136 and power circuitry 117. WD 110 may include multiple sets of one or more of the illustrated components for different wireless technologies supported by WD 110, such as, for example, GSM, WCDMA, LTE, NR, WiFi, WiMAX, or Bluetooth wireless technologies, just to mention a few. These wireless technologies may be integrated into the same or different chips or set of chips as other components within WD 110.

Antenna 111 may include one or more antennas or antenna arrays, configured to send and/or receive wireless signals, and is connected to interface 114. In certain alternative embodiments, antenna 111 may be separate from WD 110 and be connectable to WD 110 through an interface or port. Antenna 111, interface 114, and/or processing circuitry 120 may be configured to perform any receiving or transmitting operations described herein as being performed by a WD. Any information, data and/or signals may be received from a network node and/or another WD. In some embodiments, radio front end circuitry and/or antenna 111 may be considered an interface.

As illustrated, interface 114 comprises radio front end circuitry 112 and antenna 111. Radio front end circuitry 112 comprise one or more filters 118 and amplifiers 116. Radio front end circuitry 112 is connected to antenna 111 and processing circuitry 120, and is configured to condition signals communicated between antenna 111 and processing circuitry 120. Radio front end circuitry 112 may be coupled to or a part of antenna 111. In some embodiments, WD 110 may not include separate radio front end circuitry 112; rather, processing circuitry 120 may comprise radio front end circuitry and may be connected to antenna 111. Similarly, in some embodiments, some or all of RF transceiver circuitry 122 may be considered a part of interface 114. Radio front end circuitry 112 may receive digital data that is to be sent out to other network nodes or WDs via a wireless connection. Radio front end circuitry 112 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 118 and/or amplifiers 116. The radio signal may then be transmitted via antenna 111. Similarly, when receiving data, antenna 111 may collect radio signals which are then converted into digital data by radio front end circuitry 112. The digital data may be passed to processing circuitry 120. In other embodiments, the interface may comprise different components and/or different combinations of components. Processing circuitry 120 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software, and/or encoded logic operable to provide, either alone or in conjunction with other WD 110 components, such as device readable medium 130, WD 110 functionality. Such functionality may include providing any of the various wireless features or benefits discussed herein. For example, processing circuitry 120 may execute instructions stored in device readable medium 130 or in memory within processing circuitry 120 to provide the functionality disclosed herein.

As illustrated, processing circuitry 120 includes one or more of RF transceiver circuitry 122, baseband processing circuitry 124, and application processing circuitry 126. In other embodiments, the processing circuitry may comprise different components and/or different combinations of components. In certain embodiments processing circuitry 120 of WD 110 may comprise a SOC. In some embodiments, RF transceiver circuitry 122, baseband processing circuitry 124, and application processing circuitry 126 may be on separate chips or sets of chips. In alternative embodiments, part or all of baseband processing circuitry 124 and application processing circuitry 126 may be combined into one chip or set of chips, and RF transceiver circuitry 122 may be on a separate chip or set of chips. In still alternative embodiments, part or all of RF transceiver circuitry 122 and baseband processing circuitry 124 may be on the same chip or set of chips, and application processing circuitry 126 may be on a separate chip or set of chips. In yet other alternative embodiments, part or all of RF transceiver circuitry 122, baseband processing circuitry 124, and application processing circuitry 126 may be combined in the same chip or set of chips. In some embodiments, RF transceiver circuitry 122 may be a part of interface 114. RF transceiver circuitry 122 may condition RF signals for processing circuitry

120

In certain embodiments, some or all of the functionality described herein as being performed by a WD may be provided by processing circuitry 120 executing instructions stored on device readable medium 130, which in certain embodiments may be a computer-readable storage medium. In alternative embodiments, some or all of the functionality may be provided by processing circuitry 120 without executing instructions stored on a separate or discrete device readable storage medium, such as in a hard-wired manner. In any of those particular embodiments, whether executing instructions stored on a device readable storage medium or not, processing circuitry 120 can be configured to perform the described functionality. The benefits provided by such functionality are not limited to processing circuitry 120 alone or to other components of WD 110, but are enjoyed by WD 110 as a whole, and/or by end users and the wireless network generally.

Processing circuitry 120 may be configured to perform any determining, calculating, or similar operations (e.g., certain obtaining operations) described herein as being performed by a WD. These operations, as performed by processing circuitry 120, may include processing information obtained by processing circuitry 120 by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored by WD 110, and/or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination.

Device readable medium 130 may be operable to store a computer program, software, an application including one or more of logic, rules, code, tables, etc. and/or other instructions capable of being executed by processing circuitry 120. Device readable medium 130 may include computer memory (e.g., Random Access Memory (RAM) or Read Only Memory (ROM)), mass storage media (e.g., a hard disk), removable storage media (e.g., a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device readable and/or computer executable memory devices that store information, data, and/or instructions that may be used by processing circuitry 120. In some embodiments, processing circuitry 120 and device readable medium 130 may be considered to be integrated.

User interface equipment 132 may provide components that allow for a human user to interact with WD 110. Such interaction may be of many forms, such as visual, audial, tactile, etc. User interface equipment 132 may be operable to produce output to the user and to allow the user to provide input to WD 110. The type of interaction may vary depending on the type of user interface equipment 132 installed in WD 110. For example, if WD 110 is a smart phone, the interaction may be via a touch screen; if WD 110 is a smart meter, the interaction may be through a screen that provides usage (e.g., the number of gallons used) or a speaker that provides an audible alert (e.g., if smoke is detected). User interface equipment 132 may include input interfaces, devices and circuits, and output interfaces, devices and circuits. User interface equipment 132 is configured to allow input of information into WD 110, and is connected to processing circuitry 120 to allow processing circuitry 120 to process the input information. User interface equipment 132 may include, for example, a microphone, a proximity or other sensor, keys/buttons, a touch display, one or more cameras, a USB port, or other input circuitry. User interface equipment 132 is also configured to allow output of information from WD 110, and to allow processing circuitry 120 to output information from WD 110. User interface equipment 132 may include, for example, a speaker, a display, vibrating circuitry, a USB port, a headphone interface, or other output circuitry. Using one or more input and output interfaces, devices, and circuits, of user interface equipment 132, WD 110 may communicate with end users and/or the wireless network, and allow them to benefit from the functionality described herein.

Auxiliary equipment 134 is operable to provide more specific functionality which may not be generally performed by WDs. This may comprise specialized sensors for doing measurements for various purposes, interfaces for additional types of communication such as wired communications etc. The inclusion and type of components of auxiliary equipment 134 may vary depending on the embodiment and/or scenario.

Power source 136 may, in some embodiments, be in the form of a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic devices or power cells, may also be used. WD 110 may further comprise power circuitry 117 for delivering power from power source 136 to the various parts of WD 110 which need power from power source 136 to carry out any functionality described or indicated herein. Power circuitry 117 may in certain embodiments comprise power management circuitry. Power circuitry 117 may additionally or alternatively be operable to receive power from an external power source; in which case WD 110 may be connectable to the external power source (such as an electricity outlet) via input circuitry or an interface such as an electrical power cable. Power circuitry 117 may also in certain embodiments be operable to deliver power from an external power source to power source 136. This may be, for example, for the charging of power source 136. Power circuitry 117 may perform any formatting, converting, or other modification to the power from power source 136 to make the power suitable for the respective components of WD 110 to which power is supplied.

FIGURE 11 illustrates one embodiment of a UE in accordance with various aspects described herein. As used herein, a user equipment or UE may not necessarily have a user in the sense of a human user who owns and/or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, a UE may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter). UE 2200 may be any UE identified by the 3^rd Generation Partnership Project (3GPP), including a NB-IoT UE, a machine type communication (MTC) UE, and/or an enhanced MTC (eMTC) UE. UE 200, as illustrated in FIGURE 11, is one example of a WD configured for communication in accordance with one or more communication standards promulgated by the 3^rd Generation Partnership Project (3GPP), such as 3GPP’s GSM, UMTS, LTE, and/or 5G standards. As mentioned previously, the term WD and UE may be used interchangeable. Accordingly, although FIGURE 11 is a UE, the components discussed herein are equally applicable to a WD, and vice-versa.

In FIGURE 11, UE 200 includes processing circuitry 201 that is operatively coupled to input/output interface 205, radio frequency (RF) interface 209, network connection interface 211, memory 215 including random access memory (RAM) 217, read-only memory (ROM) 219, and storage medium 221 or the like, communication subsystem 231, power source 233, and/or any other component, or any combination thereof. Storage medium 221 includes operating system 223, application program 225, and data 227. In other embodiments, storage medium 221 may include other similar types of information. Certain UEs may utilize all of the components shown in FIGURE 11, or only a subset of the components. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc. In FIGURE 11, processing circuitry 201 may be configured to process computer instructions and data. Processing circuitry 201 may be configured to implement any sequential state machine operative to execute machine instructions stored as machine-readable computer programs in the memory, such as one or more hardware-implemented state machines (e.g., in discrete logic, FPGA, ASIC, etc.); programmable logic together with appropriate firmware; one or more stored program, general-purpose processors, such as a microprocessor or Digital Signal Processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 201 may include two central processing units (CPUs). Data may be information in a form suitable for use by a computer.

In the depicted embodiment, input/output interface 205 may be configured to provide a communication interface to an input device, output device, or input and output device. UE 200 may be configured to use an output device via input/output interface 205. An output device may use the same type of interface port as an input device. For example, a USB port may be used to provide input to and output from UE 200. The output device may be a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. UE 200 may be configured to use an input device via input/output interface 205 to allow a user to capture information into UE 200. The input device may include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, another like sensor, or any combination thereof. For example, the input device may be an accelerometer, a magnetometer, a digital camera, a microphone, and an optical sensor.

In FIGURE 11, RF interface 209 may be configured to provide a communication interface to RF components such as a transmitter, a receiver, and an antenna. Network connection interface 211 may be configured to provide a communication interface to network 243a. Network 243a may encompass wired and/or wireless networks such as a local-area network (LAN), a wide-area network (WAN), a computer network, a wireless network, a telecommunications network, another like network or any combination thereof. For example, network 243a may comprise a Wi-Fi network. Network connection interface 211 may be configured to include a receiver and a transmitter interface used to communicate with one or more other devices over a communication network according to one or more communication protocols, such as Ethernet, TCP/IP, SONET, ATM, or the like. Network connection interface 211 may implement receiver and transmitter functionality appropriate to the communication network links (e.g., optical, electrical, and the like). The transmitter and receiver functions may share circuit components, software or firmware, or alternatively may be implemented separately.

RAM 217 may be configured to interface via bus 202 to processing circuitry 201 to provide storage or caching of data or computer instructions during the execution of software programs such as the operating system, application programs, and device drivers. ROM 219 may be configured to provide computer instructions or data to processing circuitry 201. For example, ROM 219 may be configured to store invariant low-level system code or data for basic system functions such as basic input and output (EO), startup, or reception of keystrokes from a keyboard that are stored in a non- volatile memory. Storage medium 221 may be configured to include memory such as RAM, ROM, programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, floppy disks, hard disks, removable cartridges, or flash drives. In one example, storage medium 221 may be configured to include operating system 223, application program 225 such as a web browser application, a widget or gadget engine or another application, and data file 227. Storage medium 221 may store, for use by UE 200, any of a variety of various operating systems or combinations of operating systems.

Storage medium 221 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), floppy disk drive, flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as a subscriber identity module or a removable user identity (SIM/RUIM) module, other memory, or any combination thereof. Storage medium 221 may allow UE 200 to access computer-executable instructions, application programs or the like, stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system may be tangibly embodied in storage medium 221, which may comprise a device readable medium.

In FIGURE 11, processing circuitry 201 may be configured to communicate with network 243b using communication subsystem 231. Network 243a and network 243b may be the same network or networks or different network or networks. Communication subsystem 231 may be configured to include one or more transceivers used to communicate with network 243b. For example, communication subsystem 231 may be configured to include one or more transceivers used to communicate with one or more remote transceivers of another device capable of wireless communication such as another WD, UE, or base station of a radio access network (RAN) according to one or more communication protocols, such as IEEE 802.2, CDMA, WCDMA, GSM, LTE, UTRAN, WiMax, or the like. Each transceiver may include transmitter 233 and/or receiver 235 to implement transmitter or receiver functionality, respectively, appropriate to the RAN links (e.g., frequency allocations and the like). Further, transmitter 233 and receiver 235 of each transceiver may share circuit components, software or firmware, or alternatively may be implemented separately.

In the illustrated embodiment, the communication functions of communication subsystem 231 may include data communication, voice communication, multimedia communication, short-range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof. For example, communication subsystem 231 may include cellular communication, Wi-Fi communication, Bluetooth communication, and GPS communication. Network 243b may encompass wired and/or wireless networks such as a local-area network (LAN), a wide-area network (WAN), a computer network, a wireless network, a telecommunications network, another like network or any combination thereof. For example, network 243b may be a cellular network, a Wi-Fi network, and/or a near-field network. Power source 213 may be configured to provide alternating current (AC) or direct current (DC) power to components of UE 200.

The features, benefits and/or functions described herein may be implemented in one of the components of UE 200 or partitioned across multiple components of UE 200. Further, the features, benefits, and/or functions described herein may be implemented in any combination of hardware, software or firmware. In one example, communication subsystem 231 may be configured to include any of the components described herein. Further, processing circuitry 201 may be configured to communicate with any of such components over bus 202. In another example, any of such components may be represented by program instructions stored in memory that when executed by processing circuitry 201 perform the corresponding functions described herein. In another example, the functionality of any of such components may be partitioned between processing circuitry 201 and communication subsystem 231. In another example, the non-computationally intensive functions of any of such components may be implemented in software or firmware and the computationally intensive functions may be implemented in hardware.

FIGURE 12 is a schematic block diagram illustrating a virtualization environment 300 in which functions implemented by some embodiments may be virtualized. In the present context, virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices and networking resources. As used herein, virtualization can be applied to a node (e.g., a virtualized base station or a virtualized radio access node) or to a device (e.g., a UE, a wireless device or any other type of communication device) or components thereof and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components (e.g., via one or more applications, components, functions, virtual machines or containers executing on one or more physical processing nodes in one or more networks).

In some embodiments, some or all of the functions described herein may be implemented as virtual components executed by one or more virtual machines implemented in one or more virtual environments 300 hosted by one or more of hardware nodes 330. Further, in embodiments in which the virtual node is not a radio access node or does not require radio connectivity (e.g., a core network node), then the network node may be entirely virtualized.

The functions may be implemented by one or more applications 320 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) operative to implement some of the features, functions, and/or benefits of some of the embodiments disclosed herein. Applications 320 are run in virtualization environment 300 which provides hardware 330 comprising processing circuitry 360 and memory 390. Memory 390 contains instructions 395 executable by processing circuitry 360 whereby application 320 is operative to provide one or more of the features, benefits, and/or functions disclosed herein.

Virtualization environment 300, comprises general-purpose or special-purpose network hardware devices 330 comprising a set of one or more processors or processing circuitry 360, which may be commercial off-the-shelf (COTS) processors, dedicated Application Specific Integrated Circuits (ASICs), or any other type of processing circuitry including digital or analog hardware components or special purpose processors. Each hardware device may comprise memory 390-1 which may be non-persistent memory for temporarily storing instructions 395 or software executed by processing circuitry 360. Each hardware device may comprise one or more network interface controllers (NICs) 370, also known as network interface cards, which include physical network interface 380. Each hardware device may also include non-transitory, persistent, machine-readable storage media 390-2 having stored therein software 395 and/or instructions executable by processing circuitry 360. Software 395 may include any type of software including software for instantiating one or more virtualization layers 350 (also referred to as hypervisors), software to execute virtual machines 340 as well as software allowing it to execute functions, features and/or benefits described in relation with some embodiments described herein.

Virtual machines 340, comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer 350 or hypervisor. Different embodiments of the instance of virtual appliance 320 may be implemented on one or more of virtual machines 340, and the implementations may be made in different ways.

During operation, processing circuitry 360 executes software 395 to instantiate the hypervisor or virtualization layer 350, which may sometimes be referred to as a virtual machine monitor (VMM). Virtualization layer 350 may present a virtual operating platform that appears like networking hardware to virtual machine 340.

As shown in FIGURE 12, hardware 330 may be a standalone network node with generic or specific components. Hardware 330 may comprise antenna 3225 and may implement some functions via virtualization. Alternatively, hardware 330 may be part of a larger cluster of hardware (e.g. such as in a data center or customer premise equipment (CPE)) where many hardware nodes work together and are managed via management and orchestration (MANO) 3100, which, among others, oversees lifecycle management of applications 320.

Virtualization of the hardware is in some contexts referred to as network function virtualization (NFV). NFV may be used to consolidate many network equipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers, and customer premise equipment.

In the context of NFV, virtual machine 340 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non- virtualized machine. Each of virtual machines 340, and that part of hardware 330 that executes that virtual machine, be it hardware dedicated to that virtual machine and/or hardware shared by that virtual machine with others of the virtual machines 340, forms a separate virtual network elements (VNE). Still in the context of NFV, Virtual Network Function (VNF) is responsible for handling specific network functions that run in one or more virtual machines 340 on top of hardware networking infrastructure 330 and corresponds to application 320 in FIGURE 12.

In some embodiments, one or more radio units 3200 that each include one or more transmitters 3220 and one or more receivers 3210 may be coupled to one or more antennas 3225. Radio units 3200 may communicate directly with hardware nodes 330 via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node or a base station.

In some embodiments, some signalling can be effected with the use of control system 3230 which may alternatively be used for communication between the hardware nodes 330 and radio units 3200.

FIGURE 13 illustrates an example telecommunication network connected via an intermediate network to a host computer in accordance with some embodiments. With reference to FIGURE 13, in accordance with an embodiment, a communication system includes telecommunication network 410, such as a 3 GPP -type cellular network, which comprises access network 411, such as a radio access network, and core network 414. Access network 411 comprises a plurality of base stations 412a, 412b, 412c, such as NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 413a, 413b, 413c. Each base station 412a, 412b, 412c is connectable to core network 414 over a wired or wireless connection

415. A first UE 491 located in coverage area 413c is configured to wirelessly connect to, or be paged by, the corresponding base station 412c. A second UE 492 in coverage area 413a is wirelessly connectable to the corresponding base station 412a. While a plurality of UEs 491, 492 are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole UE is in the coverage area or where a sole UE is connecting to the corresponding base station 412.

Telecommunication network 410 is itself connected to host computer 430, which may be embodied in the hardware and/or software of a standalone server, a cloud-implemented server, a distributed server or as processing resources in a server farm. Host computer 430 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. Connections 421 and 422 between telecommunication network 410 and host computer 430 may extend directly from core network 414 to host computer 430 or may go via an optional intermediate network 420. Intermediate network 420 may be one of, or a combination of more than one of, a public, private or hosted network; intermediate network 420, if any, may be a backbone network or the Internet; in particular, intermediate network 420 may comprise two or more sub-networks (not shown).

The communication system of FIGURE 13 as a whole enables connectivity between the connected UEs 491, 492 and host computer 430. The connectivity may be described as an over-the-top (OTT) connection 450. Host computer 430 and the connected UEs 491, 492 are configured to communicate data and/or signaling via OTT connection 450, using access network 411, core network 414, any intermediate network 420 and possible further infrastructure (not shown) as intermediaries. OTT connection 450 may be transparent in the sense that the participating communication devices through which OTT connection 450 passes are unaware of routing of uplink and downlink communications. For example, base station 412 may not or need not be informed about the past routing of an incoming downlink communication with data originating from host computer 430 to be forwarded (e.g., handed over) to a connected UE 491. Similarly, base station 412 need not be aware of the future routing of an outgoing uplink communication originating from the UE 491 towards the host computer 430.

FIGURE 14 illustrates an example host computer communicating via a base station with a user equipment over a partially wireless connection in accordance with some embodiments. Example implementations, in accordance with an embodiment, of the UE, base station and host computer discussed in the preceding paragraphs will now be described with reference to FIGURE 14. In communication system 500, host computer 510 comprises hardware 515 including communication interface 516 configured to set up and maintain a wired or wireless connection with an interface of a different communication device of communication system 500. Host computer 510 further comprises processing circuitry 518, which may have storage and/or processing capabilities. In particular, processing circuitry 518 may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. Host computer 510 further comprises software 511, which is stored in or accessible by host computer 510 and executable by processing circuitry 518. Software 511 includes host application 512. Host application 512 may be operable to provide a service to a remote user, such as UE 530 connecting via OTT connection 550 terminating at UE 530 and host computer 510. In providing the service to the remote user, host application 512 may provide user data which is transmitted using OTT connection 550.

Communication system 500 further includes base station 520 provided in a telecommunication system and comprising hardware 525 enabling it to communicate with host computer 510 and with UE 530. Hardware 525 may include communication interface 526 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of communication system 500, as well as radio interface 527 for setting up and maintaining at least wireless connection 570 with UE 530 located in a coverage area (not shown in FIGURE 14) served by base station 520. Communication interface 526 may be configured to facilitate connection 560 to host computer 510. Connection 560 may be direct or it may pass through a core network (not shown in FIGURE 14) of the telecommunication system and/or through one or more intermediate networks outside the telecommunication system. In the embodiment shown, hardware 525 of base station 520 further includes processing circuitry 528, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. Base station 520 further has software 521 stored internally or accessible via an external connection.

Communication system 500 further includes UE 530 already referred to. Its hardware 535 may include radio interface 537 configured to set up and maintain wireless connection 570 with a base station serving a coverage area in which UE 530 is currently located. Hardware 535 of UE 530 further includes processing circuitry 538, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. UE 530 further comprises software 531, which is stored in or accessible by UE 530 and executable by processing circuitry 538. Software 531 includes client application 532. Client application 532 may be operable to provide a service to a human or non-human user via UE 530, with the support of host computer 510. In host computer 510, an executing host application 512 may communicate with the executing client application 532 via OTT connection 550 terminating at UE 530 and host computer 510. In providing the service to the user, client application 532 may receive request data from host application 512 and provide user data in response to the request data. OTT connection 550 may transfer both the request data and the user data. Client application 532 may interact with the user to generate the user data that it provides. It is noted that host computer 510, base station 520 and UE 530 illustrated in

FIGURE 14 may be similar or identical to host computer 430, one of base stations 412a, 412b, 412c and one of UEs 491, 492 of FIGURE 13, respectively. This is to say, the inner workings of these entities may be as shown in FIGURE 14 and independently, the surrounding network topology may be that of FIGURE 13. In FIGURE 14, OTT connection 550 has been drawn abstractly to illustrate the communication between host computer 510 and UE 530 via base station 520, without explicit reference to any intermediary devices and the precise routing of messages via these devices. Network infrastructure may determine the routing, which it may be configured to hide from UE 530 or from the service provider operating host computer 510, or both. While OTT connection 550 is active, the network infrastructure may further take decisions by which it dynamically changes the routing (e.g., on the basis of load balancing consideration or reconfiguration of the network).

Wireless connection 570 between UE 530 and base station 520 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to UE 530 using OTT connection 550, in which wireless connection 570 forms the last segment.

A measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring OTT connection 550 between host computer 510 and UE 530, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring OTT connection 550 may be implemented in software 511 and hardware 515 of host computer 510 or in software 531 and hardware 535 of UE 530, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which OTT connection 550 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software 511, 531 may compute or estimate the monitored quantities. The reconfiguring of OTT connection 550 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect base station 520, and it may be unknown or imperceptible to base station 520. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling facilitating host computer 510’s measurements of throughput, propagation times, latency and the like. The measurements may be implemented in that software 511 and 531 causes messages to be transmitted, in particular empty or ‘dummy’ messages, using OTT connection 550 while it monitors propagation times, errors etc.

FIGURE 15 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to FIGURES 13 and 14. For simplicity of the present disclosure, only drawing references to FIGURE 15 will be included in this section. In step 610, the host computer provides user data. In substep 611 (which may be optional) of step 610, the host computer provides the user data by executing a host application. In step 620, the host computer initiates a transmission carrying the user data to the UE. In step 630 (which may be optional), the base station transmits to the UE the user data which was carried in the transmission that the host computer initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 640 (which may also be optional), the UE executes a client application associated with the host application executed by the host computer. FIGURE 16 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to FIGURES 13 and 14. For simplicity of the present disclosure, only drawing references to FIGURE 16 will be included in this section. In step 710 of the method, the host computer provides user data. In an optional substep (not shown) the host computer provides the user data by executing a host application. In step 720, the host computer initiates a transmission carrying the user data to the UE. The transmission may pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure. In step 730 (which may be optional), the UE receives the user data carried in the transmission.

FIGURE 17 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to FIGURES 13 and 14. For simplicity of the present disclosure, only drawing references to FIGURE 17 will be included in this section. In step 810 (which may be optional), the UE receives input data provided by the host computer. Additionally or alternatively, in step 820, the UE provides user data. In substep 821 (which may be optional) of step 820, the UE provides the user data by executing a client application. In substep 811 (which may be optional) of step 810, the UE executes a client application which provides the user data in reaction to the received input data provided by the host computer. In providing the user data, the executed client application may further consider user input received from the user. Regardless of the specific manner in which the user data was provided, the UE initiates, in sub step 830 (which may be optional), transmission of the user data to the host computer. In step 840 of the method, the host computer receives the user data transmitted from the UE, in accordance with the teachings of the embodiments described throughout this disclosure.

FIGURE 18 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to FIGURES 13 and 14. For simplicity of the present disclosure, only drawing references to FIGURE 18 will be included in this section. In step 910 (which may be optional), in accordance with the teachings of the embodiments described throughout this disclosure, the base station receives user data from the UE. In step 920 (which may be optional), the base station initiates transmission of the received user data to the host computer. In step 930 (which may be optional), the host computer receives the user data carried in the transmission initiated by the base station.

Any appropriate steps, methods, features, functions, or benefits disclosed herein may be performed through one or more functional units or modules of one or more virtual apparatuses. Each virtual apparatus may comprise a number of these functional units. These functional units may be implemented via processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include digital signal processors (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as read-only memory (ROM), random-access memory (RAM), cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and/or data communications protocols as well as instructions for carrying out one or more of the techniques described herein. In some implementations, the processing circuitry may be used to cause the respective functional unit to perform corresponding functions according one or more embodiments of the present disclosure.

FIGURE 19 depicts a method 1000 by a network node 160, according to certain embodiments. The method begins at step 1002 with the network node obtaining an overlapping CSI-RS resource definition comprising an M port CSI-RS resource definition and an N port CSI-RS resource definition, wherein N is less than M and the N ports are a subset of the M ports. The overlapping CSI-RS definition comprises a legacy M-port CSI-RS resource which comprises CDMed antenna port groups and a N-port CSI-RS resource without CDM, which overlaps with one CDM group of the M-port CSI-RS resource. At step 1004, the network node transmits the overlapping CSI-RS resource definition to a wireless device. The wireless device may calculate CSI using the overlapping CSI-RS resource definition according to any of the embodiments or examples described above. At step 1006, the network node receives the CSI report from the wireless device.

FIGURE 20 illustrates a schematic block diagram of an apparatus 1100 in a wireless network (for example, the wireless network shown in FIGURE 8). The apparatus may be implemented in a wireless device or network node (e.g., wireless device 110 or network node 160 shown in FIGURE 8). Apparatus 1100 is operable to carry out the example method described with reference to FIGURE 19 and possibly any other processes or methods disclosed herein. It is also to be understood that the method of FIGURE 19 is not necessarily carried out solely by apparatus 1100. At least some operations of the method can be performed by one or more other entities. Virtual Apparatus 1100 may comprise processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include digital signal processors (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as read-only memory (ROM), random-access memory, cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and/or data communications protocols as well as instructions for carrying out one or more of the techniques described herein, in several embodiments. In some implementations, the processing circuitry may be used to cause obtaining unit 1102, transmitting unit 1104, receiving unit 1106, and any other suitable units of apparatus 1100 to perform corresponding functions according one or more embodiments of the present disclosure.

As illustrated in FIGURE 20, apparatus 1100 includes obtaining unit 1102, transmitting unit 1104, and receiving unit 1106. Obtaining unit 1102 is configured to obtain an overlapping CSI-RS resource definition comprising an M port CSI-RS resource definition and an N port CSI-RS resource definition according to any of the embodiments and/or examples described herein. Transmitting unit 1104 is configured to transmit the overlapping CSI-RS resource definition to one or more wireless devices. Receiving unit 1106 is configured to receive CSI reports from one or more wireless devices. The term unit may have conventional meaning in the field of electronics, electrical devices and/or electronic devices and may include, for example, electrical and/or electronic circuitry, devices, modules, processors, memories, logic solid state and/or discrete devices, computer programs or instructions for carrying out respective tasks, procedures, computations, outputs, and/or displaying functions, and so on, as such as those that are described herein.

FIGURE 21 depicts a method 1200 by a wireless device 110 for computing CSI, according to certain embodiments. The method begins at step 1202 when the wireless device 110 obtains an N-port CSI-RS resource configuration. The N-port CSI-RS resource configuration includes a number of antenna ports, N, without CDM, and N is greater than one. At step 1204, the wireless device 110 computes CSI based on the N-port CSI-RS resource configuration. At step 1206, the wireless device 110 reports the CSI to a network node 160.

In a particular embodiment, at least one antenna port associated with the N- port CSI-RS resource configuration overlaps with at least one antenna port group associated with a M-port CSI-RS resource configuration with CDM.

In a particular embodiment, two or more antenna ports within the at least one antenna port group are mapped to a same first resource element comprised within the M-port CSI-RS resource configuration with CDM and at most one of the at least one antenna port is mapped to a second resource element comprised within the N-port C SI- RS resource configuration without CDM.

In a further particular embodiment, the second resource element is the same first resource element.

In a further particular embodiment, computing the CSI based on the N-port CSI-RS resource configuration comprises performing a channel measurement for each antenna port based on a single resource element of the M-port CSI-RS resource configuration. In a further particular embodiment, the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is less than a number of antenna ports, M, associated with the M-port CSI-RS resource configuration, and the at least one antenna port group comprises antenna ports in a same CDM group. In a further particular embodiment, the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is 8 and the number of antenna ports, M, associated with the M-port CSI-RS resource configuration is 32.

In a particular embodiment, the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is 8. In a particular embodiment, obtaining the N-port CSI-RS resource configuration comprises receiving the N-port CSI-RS resource configuration from the network node.

FIGURE 22 illustrates a schematic block diagram of an apparatus 1300 in a wireless network (for example, the wireless network shown in FIGURE 8). The apparatus may be implemented in a wireless device or network node (e.g., wireless device 110 or network node 160 shown in FIGURES 8-10). Apparatus 1300 is operable to carry out the example method described with reference to FIGURE 21 and possibly any other processes or methods disclosed herein. It is also to be understood that the method of FIGURE 21 is not necessarily carried out solely by apparatus 1300. At least some operations of the method can be performed by one or more other entities.

Virtual Apparatus 1300 may comprise processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include digital signal processors (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as read-only memory (ROM), random-access memory, cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and/or data communications protocols as well as instructions for carrying out one or more of the techniques described herein, in several embodiments. In some implementations, the processing circuitry may be used to cause obtaining unit 1302, computing unit 1304, reporting unit 1306, and any other suitable units of apparatus 1300 to perform corresponding functions according one or more embodiments of the present disclosure.

As illustrated in FIGURE 22, apparatus or wireless device 1300 includes obtaining unit 1302, computing unit 1304, and reporting unit 1306. The wireless device 1300 and/or obtaining unit 1302 is configured to obtain an N-port CSI-RS resource configuration. The N-port CSI-RS resource configuration includes a number of antenna ports, N, without CDM. N is greater than one. In a particular embodiment, the wireless device 1300 and/or the obtaining unit 1302 being configured to obtain the N-port CSI-RS resource configuration comprises the wireless device 1300 and/or the obtaining unit 1302 being configured to receive the N-port CSI-RS resource configuration from the network node 160.

In a particular embodiment, at least one antenna port associated with the N- port CSI-RS resource configuration without CDM overlaps with at least one antenna port group associated with an M-port CSI-RS resource configuration with CDM. In a further particular embodiment, two or more antenna ports within the at least one antenna port group are mapped to a same first resource element comprised within the M-port CSI-RS resource configuration with CDM and at most one of the at least one antenna port is mapped to a second resource element comprised within the N-port CSI- RS resource configuration without CDM. In still a further particular embodiment, the second resource element is the same first resource element.

In a particular embodiment, the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is less than a number of antenna ports, M, associated with the M-port CSI-RS resource configuration, and the at least one antenna port group comprises antenna ports in a same CDM group. In a further particular embodiment, the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is 8 and the number of antenna ports, M, associated with the M-port CSI-RS resource configuration is 32.

In a particular embodiment, the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is 8. Wireless device 1300 and/or computing unit 1304 is configured to compute

CSI based on the N-port CSI-RS resource configuration. In a particular embodiment, when computing the CSI based on the N-port CSI-RS resource configuration, the wireless device 1300 and/or computing unit 1304 is configured to perform a channel measurement for each antenna port based on a single resource element of the M-port CSI-RS resource configuration. Wireless device 1300 and/or reporting unit 1306 is configured to report the CSI to a network node 160.

The term unit may have conventional meaning in the field of electronics, electrical devices and/or electronic devices and may include, for example, electrical and/or electronic circuitry, devices, modules, processors, memories, logic solid state and/or discrete devices, computer programs or instructions for carrying out respective tasks, procedures, computations, outputs, and/or displaying functions, and so on, as such as those that are described herein.

FIGURE 23 depicts a method 1400 by a network node 160 for configuring a wireless device 110 to report CSI, according to certain embodiments. The method begins at step 1402 with the network node 160 computes an N-port CSI-RS resource configuration. The N-port CSI-RS resource configuration includes a number of antenna ports, N, without CDM, and N is greater than one. At least one antenna port associated with the N-port CSI-RS resource configuration overlaps with at least one antenna port group associated with an M-port CSI-RS resource configuration with CDM. At step 1404, the network node 160 transmits CSI-RS over the N-port CSI-RS resource configuration to the wireless device for CSI computation. At step 1406, the network node 160 receives CSI from the wireless device according to the N-port CSI- RS resource configuration.

In a particular embodiment, two or more antenna ports within the at least one antenna port group are mapped to a same first resource element comprised within the M-port CSI-RS resource configuration with CDM and at most one of the at least one antenna port is mapped to a second resource element comprised within the N-port CSI- RS resource configuration without CDM.

In a further particular embodiment, the second resource element is the same first resource element. In a particular embodiment, the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is less than a number of antenna ports, M, associated with the M-port CSI-RS resource configuration, and the at least one antenna port group comprises antenna ports in a same CDM group. In a particular embodiment, the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is 8 and the number of antenna ports, M, associated with the M-port CSI-RS resource configuration is 32.

FIGURE 24 illustrates a schematic block diagram of an apparatus 1500 in a wireless network (for example, the wireless network shown in FIGURE 8). The apparatus may be implemented in a wireless device or network node (e.g., wireless device 110 or network node 160 shown in FIGURES 8-10). Apparatus 1500 is operable to carry out the example method described with reference to FIGURE 23 and possibly any other processes or methods disclosed herein. It is also to be understood that the method of FIGURE 23 is not necessarily carried out solely by apparatus 1500. At least some operations of the method can be performed by one or more other entities.

Virtual Apparatus 1500 may comprise processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include digital signal processors (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as read-only memory (ROM), random-access memory, cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and/or data communications protocols as well as instructions for carrying out one or more of the techniques described herein, in several embodiments. In some implementations, the processing circuitry may be used to cause computing unit 1502, transmitting unit 1504, receiving unit 1506, and any other suitable units of apparatus 1500 to perform corresponding functions according one or more embodiments of the present disclosure.

As illustrated in FIGURE 24, apparatus or network node 1500 includes computing unit 1502, transmitting unit 1504, and receiving unit 1506. Network node 1500 and/or computing unit 1502 is configured to compute an N-port CSI-RS resource configuration. The N-port CSI-RS resource configuration includes a number of antenna ports, N, without CDM, and N is greater than one. At least one antenna port associated with the N-port CSI-RS resource configuration overlaps with at least one antenna port group associated with an M-port CSI-RS resource configuration with CDM.

In a particular embodiment, two or more antenna ports within the at least one antenna port group associated with the M-port CSI-RS resource configuration with CDM are mapped to a same first resource element comprised within the antenna port group associated with the M-port CSI-RS resource configuration with CDM and at most one antenna port associated with the N-port CSI-RS resource configuration is mapped to a second resource element comprised within the N-port CSI-RS resource configuration without CDM. In a further particular embodiment, the second resource element is the same first resource element.

Network node 1500 and/or transmitting unit 1504 is configured to transmit CSI-RS over the N-port CSI-RS resource configuration to the wireless device for CSI computation.

Network node 1500 and/or receiving unit 1506 is configured to receive CSI from the wireless device according to the N-port CSI-RS resource configuration.

The term unit may have conventional meaning in the field of electronics, electrical devices and/or electronic devices and may include, for example, electrical and/or electronic circuitry, devices, modules, processors, memories, logic solid state and/or discrete devices, computer programs or instructions for carrying out respective tasks, procedures, computations, outputs, and/or displaying functions, and so on, such as those that are described herein. EXAMPLES

Example EE A method performed by a wireless device for calculating channel state information (CSI), the method comprising: obtaining an overlapping CSI-RS resource definition comprising an M port CSI-RS resource definition and an N port CSI-RS resource definition, wherein N is less than M and the N ports are a subset of the M ports; calculating CSI based on the overlapping CSI-RS definition; and reporting the CSI to a network node.

Example E2. The method of Example El, wherein the overlapping CSI-RS definition comprises a legacy M-port CSI-RS resource which comprises CDMed antenna port groups and a N-port CSI-RS resource without CDM, which overlaps with one CDM group of the M-port CSI-RS resource.

Example E3. The method of any of the previous Examples, further comprising: providing user data; and forwarding the user data to a host computer via the transmission to the base station.

Example E4. A method performed by a base station for configuring wireless device to report CSI, the method comprising: obtaining an overlapping CSI-RS resource definition comprising an M port CSI-RS resource definition and an N port CSI-RS resource definition, wherein N is less than M and the N ports are a subset of the M ports; transmitting the overlapping CSI-RS resource definition to a wireless device; and receiving CSI from the wireless device according to the overlapping CSI- RS resource definition.

Example E5. The method of Example E4, wherein the overlapping CSI-RS definition comprises a legacy M-port CSI-RS resource which comprises CDMed antenna port groups and a N-port CSI-RS resource without CDM, which overlaps with one CDM group of the M-port CSI-RS resource.

Example E6. The method of any of the previous Examples, further comprising: obtaining user data; and forwarding the user data to a host computer or a wireless device. Example E7. A wireless device for calculating channel state information

(CSI), the wireless device comprising: processing circuitry configured to perform any of the steps of any of Examples El to E3; and power supply circuitry configured to supply power to the wireless device.

Example E8. A base station for configuring wireless device to report CSI, the base station comprising: processing circuitry configured to perform any of the steps of any of Examples E4 to E7; power supply circuitry configured to supply power to the wireless device.

Claims

1. A method (1200) by a wireless device (110) for computing channel state information, CSI, the method (1200) comprising: obtaining (1202) an N-port Channel State Information-Reference Signal, CSI- RS, resource configuration, the N-port CSI-RS resource configuration comprising a number of antenna ports, N, without Code Division multiplexing, CDM, wherein N is greater than one; computing (1204) CSI based on the N-port CSI-RS resource configuration; and reporting (1206) the CSI to a network node (160).

2. The method of Claim 1, wherein at least one antenna port associated with the

N-port CSI-RS resource configuration without CDM overlaps with at least one antenna port group associated with a M-port CSI-RS resource configuration with CDM.

3. The method of Claim 2, wherein two or more antenna ports within the at least one antenna port group are mapped to a same first resource element comprised within the M-port CSI-RS resource configuration with CDM and at most one of the at least one antenna port is mapped to a second resource element comprised within the N-port CSI-RS resource configuration without CDM.

4. The method of Claim 3, wherein the second resource element is the same first resource element.

5. The method of any one of Claims 2 to 4, wherein computing the CSI based on the N-port CSI-RS resource configuration comprises performing a channel measurement for each antenna port based on a single resource element of the M-port CSI-RS resource configuration.

6. The method of any one of Claims 2 to 5, wherein the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is less than a number of antenna ports, M, associated with the M-port CSI-RS resource configuration, and the at least one antenna port group comprises antenna ports in a same CDM group.

7. The method of Claim 6, wherein the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is 8 and the number of antenna ports, M, associated with the M-port CSI-RS resource configuration is 32.

8. The method of any one of Claims 1 to 6, wherein the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is 8.

9. The method of any one of Claims 1 to 8, wherein obtaining the N-port CSI-RS resource configuration comprises receiving the N-port CSI-RS resource configuration from the network node.

10. A method (1400) by a network node (160) for configuring a wireless device (110) to report Channel State Information, CSI, the method (1400) comprising: computing (1402) an N-port Channel State Information-Reference Signal, CSI- RS, resource configuration, the N-port CSI-RS resource configuration comprising a number of antenna ports, N, without Code Division Multiplexing, CDM, wherein N is greater than one, and wherein at least one antenna port associated with the N-port CSI- RS resource configuration overlaps with at least one antenna port group associated with an M-port CSI-RS resource configuration with CDM; transmitting (1404) CSI-RS over the N-port CSI-RS resource configuration to the wireless device for CSI computation; and receiving (1406) CSI from the wireless device according to the N-port CSI-RS resource configuration.

11. The method of Claim 10, wherein two or more antenna ports within the at least one antenna port group are mapped to a same first resource element comprised within the M-port CSI-RS resource configuration with CDM and at most one of the at least one antenna port is mapped to a second resource element comprised within the N-port CSI-RS resource configuration without CDM.

12. The method of Claim 11, wherein the second resource element is the same first resource element.

13. The method of any one of Claims 10 to 12, wherein the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is less than a number of antenna ports, M, associated with the M-port CSI-RS resource configuration, and the at least one antenna port group comprises antenna ports in a same CDM group.

14. The method of Claim 13, wherein the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is 8 and the number of antenna ports, M, associated with the M-port CSI-RS resource configuration is 32.

15. A wireless device (110, 1300) for computing channel state information, CSI, the wireless device (110, 1300) comprising: processing circuitry (120) configured to: obtain an N-port Channel State Information-Reference Signal, C SI- RS, resource configuration, the N-port CSI-RS resource configuration comprising a number of antenna ports, N, without Code Division multiplexing, CDM, wherein N is greater than one; compute CSI based on the N-port CSI-RS resource configuration; and report the CSI to a network node (160).

16. The wireless device of Claim 15, wherein at least one antenna port associated with the N-port CSI-RS resource configuration without CDM overlaps with at least one antenna port group associated with a M-port CSI-RS resource configuration with CDM.

17. The wireless device of Claim 16, wherein two or more antenna ports within the at least one antenna port group are mapped to a same first resource element comprised within the M-port CSI-RS resource configuration with CDM and at most one of the at least one antenna port is mapped to a second resource element comprised within the N-port CSI-RS resource configuration without CDM.

18. The wireless device of Claim 17, wherein the second resource element is the same first resource element.

19. The wireless device of any one of Claims 16 to 18, wherein computing the CSI based on the N-port CSI-RS resource configuration comprises performing a channel measurement for each antenna port based on a single resource element of the M-port CSI-RS resource configuration.

20. The wireless device of any one of Claims 16 to 19, wherein the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is less than a number of antenna ports, M, associated with the M-port CSI-RS resource configuration, and the at least one antenna port group comprises antenna ports in a same CDM group.

21. The wireless device of Claim 20, wherein the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is 8 and the number of antenna ports, M, associated with the M-port CSI-RS resource configuration is 32.

22. The wireless device of any one of Claims 15 to 20, wherein the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is 8.

23. The wireless device of any one of Claims 15 to 22, wherein obtaining the N-port CSI-RS resource configuration comprises receiving the N-port CSI-RS resource configuration from the network node.

24. A network node (160, 1500) for configuring a wireless device (110) to report CSI, the network node (160, 1500) comprising: processing circuitry (170) configured to: compute an N-port Channel State Information-Reference Signal, CSI- RS, resource configuration, the N-port CSI-RS resource configuration comprising a number of antenna ports, N, without Code Division Multiplexing, CDM, wherein N is greater than one, and wherein at least one antenna port associated with the N-port CSI- RS resource configuration overlaps with at least one antenna port group associated with an M-port CSI-RS resource configuration with CDM; transmit CSI-RS over the N-port CSI-RS resource configuration to the wireless device for CSI computation; and receive CSI from the wireless device according to the N-port CSI-RS resource configuration.

25. The network node of Claim 24, wherein two or more antenna ports within the at least one antenna port group are mapped to a same first resource element comprised within the M-port CSI-RS resource configuration with CDM and at most one of the at least one antenna port is mapped to a second resource element comprised within the N-port CSI-RS resource configuration without CDM.

26. The network node of Claim 25, wherein the second resource element is the same first resource element.

27. The network node of any one of Claims 24 to 26, wherein the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is less than a number of antenna ports, M, associated with the M-port CSI-RS resource configuration, and the at least one antenna port group comprises antenna ports in a same CDM group.

28. The network node of Claim 27, wherein the number of antenna ports, N, associated with the N-port CSI-RS resource configuration is 8 and the number of antenna ports, M, associated with the M-port CSI-RS resource configuration is 32.