About values for the Matlab's communication channel

Where can I get the details about implementing MIMO channel as per my simulation need.

I need to implement an indoor setup with 3.5 GHz tranmission with 4x2 and 4x4 transmission.

However, I am unable to find a refernce for which I can get teh specfic values of MIMO channel properties. In particular, for example, what will be the samplerates, PathDelays etc. Is there any reference, or what 3GPP specification can I use for this purpose?

 comm.MIMOChannel with properties:

                         SampleRate: 1
                         PathDelays: 0
                   AveragePathGains: 0
                 NormalizePathGains: true
                 FadingDistribution: 'Rayleigh'
                MaximumDopplerShift: 1.0000e-03
                    DopplerSpectrum: [1×1 struct]
    SpatialCorrelationSpecification: 'Separate Tx Rx'
          TransmitCorrelationMatrix: [2×2 double]
           ReceiveCorrelationMatrix: [2×2 double]
                   AntennaSelection: 'Off'
            NormalizeChannelOutputs: true
                   ChannelFiltering: true
                PathGainsOutputPort: false