info

Characteristic information of link-level MIMO channel

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Syntax

channelInfo = info(channel)

Description

channelInfo = info(channel) returns characteristic information of the link-level multi-input multi-output (MIMO) channel model, channel.

example

Examples

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Open Live Script

Create an nrTDLChannel System object.

tdl = nrTDLChannel;

To get characteristic information about the channel, call the info function on the object.

channelInfo = info(tdl)
channelInfo = struct with fields:
          ChannelFilterDelay: 7
         MaximumChannelDelay: 16
                  PathDelays: [0 1.1457e-08 1.2075e-08 1.7604e-08 1.3830e-08 1.6125e-08 2.0124e-08 1.7250e-08 2.2854e-08 4.6125e-08 5.6934e-08 6.6726e-08 6.5154e-08 7.4826e-08 7.5357e-08 9.1746e-08 1.2243e-07 1.3374e-07 1.3708e-07 … ] (1×23 double)
            AveragePathGains: [-13.4000 0 -2.2000 -4 -6 -8.2000 -9.9000 -10.5000 -7.5000 -15.9000 -6.6000 -16.7000 -12.4000 -15.2000 -10.8000 -11.3000 -12.7000 -16.2000 -18.3000 -18.9000 -16.6000 -19.9000 -29.7000]
             KFactorFirstTap: -Inf
         NumTransmitAntennas: 1
          NumReceiveAntennas: 2
    SpatialCorrelationMatrix: [2×2 double]

Input Arguments

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MIMO channel model, specified as an nrCDLChannel, nrTDLChannel, or nrHSTChannel (since R2022b) System object™.

Output Arguments

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Characteristic information of the channel model, channel, returned as a structure. The fields of the structure depend on the input channel.

  • If channel is an nrCDLChannel System object, the channelInfo structure has these fields.

    Parameter FieldValueDescription
    PathDelays

    Numeric row vector

    Delays of discrete channel paths for each cluster in seconds, returned as a numeric row vector. These values include the effects of DelaySpread scaling and KFactorScaling (when enabled).

    ClusterTypes

    Cell array of character vectors

    Type of each cluster in the delay profile, returned as a cell array of character vectors. Cluster types can be 'LOS', 'SubclusteredNLOS', or 'NLOS'.

    AveragePathGains

    Numeric row vector

    Average path gains of the discrete path or clusters in dB, returned as a numeric row vector. These values include the effect of KFactorScaling scaling (when enabled).

    AnglesAoD

    Numeric row vector

    Azimuth of departure angles of the clusters in degrees, returned as a numeric row vector.

    AnglesAoA

    Numeric row vector

    Azimuth of arrival angles of the clusters in degrees, returned as a numeric row vector.

    AnglesZoD

    Numeric row vector

    Zenith of departure angles of the clusters in degrees, returned as a numeric row vector.

    AnglesZoA

    Numeric row vector

    Zenith of arrival angles of the clusters in degrees, returned as a numeric row vector.

    KFactorFirstCluster

    Numeric scalar

    K-factor of first cluster of delay profile in dB, returned as a numeric scalar. If the first cluster of the delay profile follows a Laplacian instead of a Rician distribution, KFactorFirstCluster is -Inf.

    NumTransmitAntennas

    Numeric scalar

    Number of transmit antenna elements, returned as a numeric scalar.

    ClusterAngleSpreads (since R2023b)

    Numeric row vector

    Cluster-wise root mean square (RMS) angle spreads in degrees, returned as a numeric row vector of the form [CASD CASA CZSD CZSA], where:

    • CASD is the cluster-wise RMS azimuth spread of departure angles.

    • CASA is the cluster-wise RMS azimuth spread of arrival angles.

    • CZSD is the cluster-wise RMS zenith spread of departure angles.

    • CZSA is the cluster-wise RMS zenith spread of arrival angles.

    The object uses these values for scaling ray offset angles within a cluster, as described in TR 38.901 Section 7.7.1, Step1.

    XPR (since R2023b)

    Numeric scalar

    NaN

    		Cross-polarization power ratio in dB, returned as a numeric scalar. When the DelayProfile property is set to 'Custom' and the XPR property is specified as a matrix, this field is returned as NaN.
    NumInputSignals

    Numeric scalar

    Number of input signals, returned as a numeric scalar. This value determines the number of columns in the input signal sent through the channel (see signalIn). The value of NumInputSignals and NumTransmitAntennas structure fields are equal, unless you specify the transmit antenna as a phased.ReplicatedSubarray (Phased Array System Toolbox) or phased.PartitionedArray (Phased Array System Toolbox) phased array object. In case of these two phased antenna arrays, NumInputSignals is equal to the number of antenna subarrays, so NumInputSignals ≤ NumTransmitAntennas.

    NumReceiveAntennas

    Numeric scalar

    Number of receive antenna elements, returned as a numeric scalar.

    NumOuputSignals

    Numeric scalar

    Number of output signals, returned as a numeric scalar. This value determines the number of columns in the output signal received from the channel (see signalOut). The value of NumOutputSignals and NumReceiveAntennas structure fields are equal, unless you specify the receive antenna as a phased.ReplicatedSubarray (Phased Array System Toolbox) or phased.PartitionedArray (Phased Array System Toolbox) phased array object. In case of these two phased antenna arrays, NumOutputSignals is equal to the number of subarrays, so NumOutputSignals ≤ NumReceiveAntennas.

    ChannelFilterDelay

    Numeric scalar

    Channel filter delay in samples, returned as a numeric scalar.

    MaximumChannelDelay (since R2022b)

    Numeric scalar

    Maximum channel delay in samples, returned as a numeric scalar. This delay consists of the maximum path delay and the channel filter delay.

    Note

    • The step of splitting the strongest clusters into subclusters, described in TR 38.901 Section 7.5, requires sorting of the clusters by their average power. If the NumStrongestClusters property is nonzero (applies only when DelayProfile is set to 'Custom'), the fields of the information structure are sorted by average power. That is, the AveragePathGains, ClusterTypes, PathDelays, AnglesAoD, AnglesAoA, AnglesZoD, and AnglesZoA fields are presented in descending order of the average gain.

    • If the HasLOSCluster property is set to true, the NLOS (Laplacian) part of that cluster and the LOS cluster are not necessarily next to each other. However, the KFactorFirstCluster field still indicates the appropriate K-factor.

  • If channel is an nrTDLChannel System object, the channelInfo structure has these fields.

    Parameter FieldValueDescription
    ChannelFilterDelay

    Numeric scalar

    Channel filter delay in samples, returned as a numeric scalar.

    MaximumChannelDelay (since R2022b)

    Numeric scalar

    Maximum channel delay in samples, returned as a numeric scalar. This delay consists of the maximum path delay and the channel filter delay.

    AveragePathGains

    Numeric row vector

    Average path gains of the discrete paths in dB, returned as a numeric row vector. These values include the effect of KFactorScaling (when enabled).

    PathDelays

    Numeric row vector

    Delays of discrete channel paths in seconds, returned as a numeric row vector. These values include the effects of DelaySpread scaling and KFactorScaling (when enabled).

    KFactorFirstTap

    Numeric scalar

    K-factor of first tap of delay profile in dB, returned as a numeric scalar. If the first tap of the delay profile follows a Rayleigh instead of a Rician distribution, KFactorFirstTap is -Inf.

    NumTransmitAntennas

    Numeric scalar

    Number of transmit antennas, returned as a numeric scalar.

    NumReceiveAntennas

    Numeric scalar

    Number of receive antennas, returned as a numeric scalar.

    SpacialCorrelationMatrix

    Numeric matrix

    Combined correlation matrix or 3-D array, returned as a numeric matrix.

  • If channel is an nrHSTChannel System object, the channelInfo structure has these fields. (since R2022b)

    Parameter FieldValueDescription
    PathDelays

    NS-by-NP numeric matrix

    Absolute propagation delays of the discrete channel paths at the input signal sample times in seconds, returned as an NS-by-NP numeric matrix, where:

    • NS is the number of input samples.

    • NP is the number of paths.

    If you call the info function before the first call of the nrHSTChannel System object, this field is returned as [].

    DopplerShifts

    NS-by-NP numeric matrix

    Doppler shifts of the discrete paths at the input signal sample times in Hz, returned as an NS-by-NP matrix.

    If you call the info function before the first call of the nrHSTChannel System object, this field is returned as [].

    PowerLevels

    NS-by-NP numeric matrix

    Path gains of the discrete paths at the input signal sample times in dB, returned as an NS-by-NP numeric matrix.

    If you call the info function before the first call of the nrHSTChannel System object, this field is returned as [].

    CarrierFrequencyNumeric scalar

    Carrier frequency (f) in Hz, returned as a numeric scalar equal to fd × c/v, where:

    • fd is the maximum Doppler shift.

    • v is the train velocity.

    • c is the speed of light.

    For static propagation conditions, when fd = 0 and v = 0, the carrier frequency is returned as NaN.

    NumTransmitAntennasPositive integer

    Number of transmit antennas, returned as a positive integer.

    • When the ChannelFiltering property is set to true, this field is equal to the second dimension of the input signal.

    • When the ChannelFiltering property is set to false, this field is equal to the NumTransmitAntennas property value.

    NumReceiveAntennasPositive integer

    Number of receive antennas, returned as a positive integer.

    ChannelFilterDelayNumeric scalarChannel filter delay in samples, returned as numeric scalar.
    MaximumChannelDelay

    Numeric scalar

    Maximum channel delay in samples, returned as a numeric scalar. This delay consists of the channel filter delay and the maximum propagation delay relative to the minimum propagation delay, Dmin/c:

    MaximumChannelDelay = ChannelFilterDelay + (MaxPropagationDelay – MinPropagationDelay).

    (since R2022b)

Data Types: struct

References

[1] 3GPP TR 38.901. “Study on channel model for frequencies from 0.5 to 100 GHz.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network.

[2] 3GPP TS 38.101-4. “NR; User Equipment (UE) radio transmission and reception; Part 4: Performance requirements.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network.

Extended Capabilities

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C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Version History

Introduced in R2018b

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See Also

Objects