info

Characteristic information of link-level MIMO channel

Syntax

channelInfo = info(channel)

Description

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

Examples

Get Characteristic Information About TDL Fading Channel

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

channel — MIMO channel model

nrCDLChannel | nrTDLChannel | nrHSTChannel

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

Output Arguments

channelInfo — Characteristic information of channel model

structure

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 Field	Value	Description
  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 Field	Value	Description
  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 Field	Value	Description
  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 [].
  CarrierFrequency	Numeric 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.
  NumTransmitAntennas	Positive 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.
  NumReceiveAntennas	Positive integer	Number of receive antennas, returned as a positive integer.
  ChannelFilterDelay	Numeric scalar	Channel 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

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

Version History

Introduced in R2018b

R2023b: channelInfo output argument returns ClusterAngleSpreads and XPR for CDL channels

The channelInfo output argument now returns ClusterAngleSpreads and XPR fields when the channel input is an nrCDLChannel System object.

R2022b: channelInfo output argument returns maximum channel delay

The channelInfo output argument returns the maximum channel delay. This delay consists of the maximum path delay and the channel filter delay.

R2022b: Characteristic information for HST channel models

The function accepts the nrHSTChannel System object as an input argument.