info

Characteristic information about UWB fading channel object

Since R2024a

Syntax

S = info(obj)

Description

S = info(obj) returns a structure containing characteristic information about the UWB fading channel System object™.

Examples

Pass 802.15.4z HPRF Signal Through Outdoor Multipath UWB Channel

Pass an 802.15.4z™ High Pulse Repetition Frequency (HPRF) signal through an outdoor multipath UWB channel.

Create a UWB waveform from random packet data.

    psdu = randi([0, 1],300,1);
    waveTx = lrwpanWaveformGenerator(psdu,lrwpanHRPConfig);
    

Create a UWB channel object for an outdoor environment with no line of sight. Display the object configuration.

    outdoorUWBChannel = uwbChannel('Outdoor', ...
        HasLOS=false, ...
        Visualization='Impulse response')

outdoorUWBChannel = 
  uwbChannel with properties:

   Delay Profile
             Environment: 'Outdoor'
                  HasLOS: false
              SampleRate: 1.9968e+09
         MaxDopplerShift: 5
           SampleDensity: 64
    MinRelativePathPower: 5
      NormalizePathGains: true
           Visualization: 'Impulse response'

   Propagation
           ChannelNumber: 0
                Distance: 10

   Realization
            RandomStream: 'Global stream'

Pass the LR-WPAN waveform through the channel and observe the impulse response.

    waveRx = outdoorUWBChannel(waveTx);

After passing a waveform through the channel, display characteristic information about the channel. Observe that the NumClusters value matches the number of clusters plotted in the impulse response.

    info(outdoorUWBChannel)

ans = struct with fields:
    EnvironmentParameterization: [1x1 struct]
                CenterFrequency: 499200000
                      Bandwidth: 499200000
                    NumClusters: 5
            ClusterArrivalTimes: [8.2597 16.5497 29.9292 108.0369 125.1609]
                ClusterEnergies: [0.9241 0.8538 0.7514 0.3563 0.3026]
               PathArrivalTimes: {1x5 cell}
       AbsolutePathArrivalTimes: {1x5 cell}
              PathAveragePowers: {1x5 cell}
                     PathPhases: {1x5 cell}
               NakagamiMFactors: {1x5 cell}
                   PathGainRate: [640]
           FrequencyFilterDelay: [25]
             ChannelFilterDelay: [0]
      ChannelFilterCoefficients: [152x312 double]

Input Arguments

obj — System object to get information from

System object

System object to get information from, specified as a uwbChannel System object.

Output Arguments

S — Structure containing object information

structure

Structure containing these fields with information about the System object. Detailed field information in this structure remains blank until the object has been called to process a waveform of input data.

EnvironmentParameterization — Environment parameters

structure

Environment parameters for the given obj.Environment and obj.HasLOS, returned as a structure containing these fields:

Field	Description	Comment
Environment	Environment type.	Specified by obj.Environment
HasLOS	Boolean indicating presence of line-of-sight component.	Specified by obj.HasLOS
ReferencePathLoss	Path loss in dB at 1 m distance.	–
PathLossExponent	Path loss exponent (γ), which determines the rate at which received power decays as a function of distance.	–
ShadowingDeviation	Standard deviation (σS) in dB of a zero-mean Gaussian distributed random variable (S), which expresses shadowing for large-scale fading.	–
AntennaLoss	Antenna loss (Αant) in dB.	–
FrequencyExponent	Frequency dependence of path loss (κ) in dB/octave that determines the rate at which received power decays as a function of frequency.	–
AverageNumClusters	Mean number of clusters (Lbar) in which rays are grouped.	–
ClusterArrivalRate	Inter-cluster arrival rate (Λ) of clusters of groups of rays, which follow a Poisson process. The value expresses the number of arrivals with 1 ns.	This property does not apply when you set obj.HasLOS to false and obj.Environment to either 'Indoor office' or 'Industrial'.
PathArrivalRate1	First (ray) arrival rate for mixed Poisson model, returned as one of the two arrival rates of rays within a cluster (λ1), which follow a Poisson process. PathArrivalRate1 is weighted by MixtureProbability. The value expresses the number of arrivals with 1 ns.	These properties do not apply when you set obj.HasLOS to false and obj.Environment to either 'Indoor office' or 'Industrial'. These properties are not applied when you set obj.HasLOS to true and obj.Environment to 'Industrial', but some values are assumed for average power calculations.
PathArrivalRate2	Second (ray) arrival rate for mixed Poisson model, returned as the other arrival rate of rays within a cluster (λ2), which follow a Poisson process. PathArrivalRate2 is weighted by the complement of the mixture probability, (1 – MixtureProbability). The value expresses the number of arrivals with 1 ns.
MixtureProbability	Mixture probability for mixed Poisson model, returned as a mixture probability (β) that specifies the relative weight of the two different ray arrival rates within a cluster (PathArrivalRate1 and PathArrivalRate2). Values must be in the range [0, 1].
ClusterEnergyDecayConstant	Inter-cluster exponential decay constant in ns, returned as a constant (Γ) determining the rate of exponential decay of the cluster integrated energy as a function of the cluster arrival time.	This property does not apply when you set obj.HasLOS to false and obj.Environment to either 'Indoor office' or 'Industrial'.
PathDecaySlope	Slope of intra-cluster exponential decay constant (κγ) proportionally affects γ1 as a function of the cluster arrival time. γ1 is a constant determining the rate of exponential decay of the power of a ray as a function of the ray arrival time.	This property does not apply when you set obj.HasLOS to false and obj.Environment to either 'Indoor office' or 'Industrial'.
PathDecayOffset	Offset of intra-cluster exponential decay constant, returned as the y-intercept value (γ0) in ns of the function relating γ1 with the cluster arrival time. γ1 is a constant determining the rate of exponential decay of the power of a ray as a function of the ray arrival time.	This property does not apply when you set obj.HasLOS to false and obj.Environment to either 'Indoor office' or 'Industrial'.
ClusterShadowingDeviation	Standard deviation of cluster shadowing (σcluster) in dB of a normally distributed random variable (Μcluster), which expresses cluster shadowing as temporal variations from the average cluster power.	This property applies when you set obj.Environment to 'Residential' or when you set obj.HasLOS to true and obj.Environment to 'Industrial'.
PDPIncreaseFactor	Increase rate of alternative power delay profile (PDP) rise (γrise) determines how quickly the alternative PDP rises.	These properties do not apply when you set obj.HasLOS to true and obj.Environment to either 'Indoor office' or 'Industrial'.
PDPDecayFactor	Decay rate of alternative PDP at later times (γ1) determines how quickly the alternative PDP decays.
FirstPathAttenuation	Attenuation of 1st component in alternative PDP, returned as the attenuation (χ) of the first multi-path component in the alternative PDP.
NakagamiMeanOffset	Offset of Nakagami m-factor mean, returned as the y-intercept value (m0) in dB of the function relating the mean value of the Nakagami m-factor with the delay of a multipath component.
NakagamiMeanSlope	Slope of Nakagami μ factor mean, returned as the slope (km) of the function relating the mean value of the Nakagami μ factor with the delay of a multipath component.
NakagamiDeviationOffset	Offset of Nakagami m-factor variance, returned as the y-intercept value (m0) in dB of the function relating the standard deviation of the Nakagami m-factor with the delay of a multipath component.
NakagamiDeviationSlope	Slope of Nakagami m-factor variance
FirstPathNakagamiMFactor	Nakagami m-factor of first (strong) component

Data Types: struct

CenterFrequency — Center frequency

positive scalar

Center frequency in hertz, returned as a positive scalar.

Bandwidth — Bandwidth

positive scalar

Bandwidth in hertz, returned as a positive scalar.

NumClusters — Number of clusters

positive integer

Number of clusters in the channel realization, returned as a positive integer.

ClusterArrivalTimes — Cluster arrival times

column vector

Cluster arrival times in the channel realization in seconds, returned as a 1-by-NumClusters vector of positive values.

ClusterEnergies — Cluster energies

column vector

Cluster energies in the channel realization in watts, returned as a 1-by-NumClusters vector of positive values.

PathArrivalTimes — Path arrival times

cell array

Path arrival times in the channel realization in seconds, returned as a 1-by-NumClusters cell array. Each element in the cell array is a 1-by-K_l vector, where K_l is the number of paths for the lth cluster.

AbsolutePathArrivalTimes — Absolute path arrival times

cell array

Absolute path arrival times in the channel realization in seconds, returned as a 1-by-NumClusters cell array. Each element in the cell array is a 1-by-K_l vector, where K_l is the number of paths for the lth cluster.

PathAveragePowers — Average power of s paths

cell array

Average power of paths in the channel realization in dB, returned as a 1-by-NumClusters cell array. Each element in the cell array is a 1-by-K_l vector, where K_l is the number of paths for the lth cluster.

PathPhases — Path phases

cell array

Path phases in the channel realization in radians, returned as a 1-by-NumClusters cell array. Each element in the cell array is a 1-by-K_l vector, where K_l is the number of paths for the lth cluster.

NakagamiMFactors — Nakagami M factors

cell array

Nakagami M factors in the channel realization, returned as a 1-by-NumClusters cell array. Each element in the cell array is a 1-by-K_l vector, where K_l is the number of paths for the lth cluster.

PathGainRate — Path gain rate

positive scalar

Path gain rate, returned as a positive scalar. The path gain rate equals 2×obj.MaxDopplerShift×obj.SampleDensity.

FrequencyFilterDelay — Frequency filter delay

positive integer

Frequency filter delay in samples, returned as a positive integer.

ChannelFilterDelay — Excess channel filter delay

positive integer

Excess channel filter delay in samples, returned as a positive integer.

ChannelFilterCoefficients — Channel filter coefficients

matrix

Channel filter coefficients, returned as a matrix. The time varying path gains are applied as gains to this non-varying filter to produce the channel output over time

References

[1] A. F. Molisch et al., "IEEE 802.15.4a Channel Model-Final Report," Tech. Rep., Document IEEE 802.1504-0062-02-004a, 2005.

Version History

Introduced in R2024a