| Column Headings | |
| AoA | |
| Enabled | AoD |
| Fading Type | AoA Azimuth Spread |
| Rician K | AoD Azimuth Spread |
| Spectral Shape | LOS AoA |
| Std Dev of Gaussian | Direct Ray AoA |
| Delay Type (LTE Moving Propagation) | Direct Ray AoD |
| Delay | XPR |
| Delay Variation Period | Phase Shift |
| Min Delay (LTE Moving Propagation) | Frequency Offset |
| Loss | Log Normal |
| Vehicle Speed | Standard Deviation |
| Doppler Frequency | Decorrelation Length |
| Carrier Frequency Coupling |
The fader paths (taps) simulate the changes that a signal undergoes as it is reflected, diffracted, and scattered from objects that are present in the propagation path. When you use a standard model, standard-compliant data is populated for all the paths as specified for the channel model.
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Run-time Adjustment of Fading Parameters For 1 Channel Generate and Fade or 1 Channel Fade (ext in) configurations:
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Restores the standard path settings in the active fader path pane for the selected channel model. (Applying this button from the Fader Setup view restores all Fader Paths to their default settings.) It also restores the default settings for the carrier frequency and the random seed.
Accesses a list of 
column headings
for path parameters that can be displayed in the Fader Path view. Click
each parameter to show or hide the visibility of that column.
Displays the channel bandwidth depending on the number of enabled paths.
Configurations with regular channels:
| Paths | Standard | R2C License (U01 or later) |
|---|---|---|
| 0-6 | 120 MHz | 160 MHz |
| 7-12 | 80 MHz | 80 MHz |
| 13-24 | 40 MHz | 40 MHz |
Configurations with split channels that require split fading Option N5106A-169 (e.g., 2x8 MIMO and 4x4 MIMO):
| Paths | Standard | R2C License (U01 or later) |
|---|---|---|
| 0-6 | 60 MHz | 80 MHz |
| 7-12 | 40 MHz | 40 MHz |
| 13-24 | 20 MHz | 20 MHz |
Displays the block diagram of the currently loaded configuration.
Values: 1 to 24
Displays the row number of the path.
Choices: On, Off
Default: MIMO: Paths 1-7: On, Paths 8-24: Off
Non-MIMO: Path 1: On, Paths 2-24: Off
Choices: Pure Doppler, Rayleigh, Rician, Suzuki
Selects the type of amplitude distribution to be applied in the fader simulation.
Pure Doppler
Simulates pure Doppler fading by using non-zero Doppler frequencies and LOS AOA not equal to 90 or 270 degrees, or constant phase fading with either zero Doppler frequency and/or LOS AOA set to 90 or 270 degrees.
Rayleigh
Simulates the rapid amplitude fluctuations where there is no direct ray component (LOS) in small scale fading environments to model local scattering near the receiver.
Rician
Adds a line-of-sight component (LOS) to the Rayleigh model. This model is often used to simulate a rural environment and small office spaces.
Suzuki
Superimposes the log normal distribution onto the Rayleigh distribution. This is often used to simulate the effects of a dense urban environment with the average received power level fluctuating slowly due to shadowing effects. If you select Suzuki as a fading type, the Log Normal parameter is also enabled.
Choices: Classical 6dB, Classical 3dB, Flat, Rounded, Gaussian, Jakes Classical, Jakes Rounded
Selects the power spectral shape of the Doppler spreading applied to the signal. The firmware uses two different methods to simulate various fading scenarios: filtered noise and Jakes method. When using Jakes method, the firmware approximates the Rayleigh distribution using a finite number of rays arriving at a receiver from all directions whereas the filtered noise method simulates an infinite number of rays. The firmware does not support mixing Jakes method and filtered noise method in the same simulation. Jakes method is only recommended if different Doppler frequencies are required on each path.
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Jakes Classical or Jakes Rounded spectra can only be used in one or two channel configurations. You must use Jakes method when you want to:
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Classical 6 dB
Represents outdoor vehicular fading environments with fixed reflectors (recommended by most standards)
Classical 3 dB
Represents outdoor vehicular fading environments with fixed reflectors (optional limit)
Flat
Represents indoor fading environments with fixed reflectors.
Rounded
Represents indoor or outdoor fading environments for fixed stations with moving reflectors.
Represents slow moving hand-held reception.
Jakes Classical
Represents vehicular fading environments with fixed reflectors (corresponds to the 3 dB and 6 dB shape using the filtered noise method).
Represents indoor or outdoor fading environments for fixed stations with moving reflectors (corresponds to the rounded shape using the filtered noise method)
This column only appears when the Spectral Shape for one or more paths is set to Gaussian.
Range: 0.05 to 0.2
Default: 0.1
Sets the path's standard deviation of the Gaussian distribution with a minimum resolution of 0.01. To set the deviation, first set the path's Spectral Shape to Gaussian. After setting the Spectral Shape to Gaussian, the Std Deviation of Gaussian column appears. Once visible, this column shows a value for each path whether Gaussian is the spectral shape. However the value is valid only while Gaussian is a path's spectral shape.
This column only appears when using an LTE moving propagation delay profile.
Choices: Fixed, Moving
Selects whether the propagation for the selected path is either fixed or moving. Fixed delay allows you to set a constant path delay. Moving delay varies the path delay over time depending on the path's Min Delay, Max Delay and Rate of Osc. settings.
Range: 0 to 2 ms
Default: MIMO: Path 1: 0, Path 2: 30 ns, Path 3: 70 ns, Path 4: 90 ns,
Path 5: 110 ns, Path 6: 190 ns, Path 7: 410 ns, Paths 8-24: 0
Non-MIMO: 0 ns
Sets the relative delay of each path. This value is added to the inherent latency of the fading hardware.
It should be noted that if multiple paths are enabled having LOS components at the same path delay and Doppler frequency shift, the power level will be incorrect. This is because the firmware assumes that each path is independent. However, in this case, the paths are not independent and the power level will not be normalized to unity. In most cases, only one LOS component is present and even if multiple LOS components are specified, they will normally be at different path delays. The assumption holds as long as the path delay values are sufficiently spaced such that the cross-correlation between delayed paths is very small (i.e. the autocorrelation function of the waveform for the LOS path delay differences is negligible).
For LTE moving propagation, moving delay is the mean delay based on the path's Min Delay and Max Delay settings.
This column only appears when using an LTE moving propagation delay profile.
Range: varies, depending on Max Delay setting
Default: 0 µs
Sets the minimum path delay for LTE moving propagation when the Delay Type is set to Moving.
This column only appears when using an LTE moving propagation delay profile.
Range: varies, depending on Min Delay setting
Default: 0 µs
Sets the maximum path delay for LTE moving propagation when the Delay Type is set to Moving.
This column only appears when using an LTE moving propagation delay profile.
Range: 0 to 50 rad/s
Default: 0.40 rad/s
Sets the rate at which the delay shifts between the Min Delay and Max Delay values.
This column only appears when using a W-CDMA moving propagation delay profile.
Range: 0 to 50 µs
Default: 5 µs
Sets the amount of time by which the delay can vary during moving propagation delay profile when using a W-CDMA moving propagation delay profile.
This column only appears when using a W-CDMA moving propagation delay profile.
Range: 1 to 1000
Default: 157.08
Sets the period of time in seconds during which the moving propagation delay variation completes one cycle.
Range: 0 to 84 dB
Default: 0
Sets the amount of relative path loss. This setting assumes that the cross-correlation between paths is very small. If not, the power may be incorrect.
Path loss or power attenuation occurs with reflected signals as a result of the added distance they travel compared to the line-of-sight signal. Other factors may also contribute to signal power attenuation, such as reflected surface characteristics.
Choices: Doppler Frequency, Vehicle Speed
Selects whether Doppler Frequency or Vehicle Speed is coupled to the Carrier Frequency that is set in the Master Setup view. The carrier frequency coupling applies to each path individually. However, for filtered noise spectral shapes, the carrier frequency coupling must be the same for all paths.
Doppler Frequency
With this choice, the Doppler frequency will be adjusted when you change the carrier frequency in the Fader Setup view.
Vehicle Speed
With this choice, the vehicle speed will be adjusted when you change the carrier frequency in the Fader Setup view.
Range: Varies depending on the maximum Doppler
frequency and the carrier frequency
Sets the speed of the vehicle. If you change the vehicle speed, the Doppler frequency will be adjusted according to the current carrier frequency. The vehicle speed resolution will decrease as the number of paths is increased or the fader bandwidth is decreased and is limited by the maximum allowable Doppler frequency. All paths are coupled unless the Spectral Shape is Jakes Classical or Jakes Rounded.
Range: 0 to 1600 Hz
Default: 0
Sets the maximum Doppler frequency. The width of the Doppler spread is twice the Doppler frequency. If you change the Doppler frequency, the vehicle speed will be adjusted accordingly.
Default: MIMO: Path
1:147.34, Path
2: 92.27, Path 3: 51.16, Path 4: 21.57, Path 5: 23.34, Path 6: 94.92,
Path 7: 19.19, Paths 8-24: 0
Range: –360 to 360 degrees
Specifies the mean of the angle of
arrival
(in degrees) of the signal for the selected path. The angle of arrival
is defined with reference to an xy (ground/antenna) plane where the x-axis
points to the geographical north and the y-axis is parallel to the ground.
Default: Path 1: 18.11, Path
2: 9.8, Path 3: 15.31, Path 4: 22.78 Path
5: 21.75, Path
6: 25.7, Path 7: 22.61, Paths 8-24: 0
Range: –360 to 360 degrees
Specifies the mean of the angle of
departure
(in degrees) of the signal for the selected path. The angle of departure
is defined with reference to an xy plane (ground/antenna) plane where
the x-axis points to the geographical north and the y-axis is parallel
to the ground.
Default: Paths 1-7:68, Paths 8-24: 0.01
Range: 0.01 to 180 degrees
Specifies the azimuth spread of the angle of arrival at the antenna arrays of the receiver. The azimuth spread characterizes the degree of dispersion of the non-LOS signals due to multipath from a large number of local reflectors. The azimuth spread impacts the power azimuth spectrum and the correlation characteristics across the elements of the antenna array.
Default: Paths 1-7:5, Paths 8-24: 0.01
Range: 0.01 to 180 degrees
Specifies the azimuth (angular) spread of the angle of departure at the antenna arrays of the transmitter. The azimuth spread characterizes the degree of dispersion of the non-LOS signals due to a large number of local reflectors. The angular spread impacts the power azimuth spectrum and the correlation characteristics across the elements of the antenna array.
Range: 0 to 180 degrees
line-of-sight
angle of arrival.
The firmware calculates the LOS Doppler shift using the LOS AoA as the
angle between the LOS component and the direction of travel.
The line-of-sight angle is defined with reference to an xy (ground/antenna)
plane where the x-axis points to the geographical north and the y-axis
is parallel to the ground.Range: –360
to 360 degrees
Default: 0 degrees
The presence of a direct ray is determined by the absence of fading on that path (e.g., a Ricean direct ray, or a pure Doppler path, or a Rayleigh path with Doppler = 0). The direct ray usually falls outside the cluster PAS; therefore the angle of arrival is usually different than the cluster AoA.
Range: –360
to 360 degrees
Default: 0 degrees
The presence of a direct ray is determined by the absence of fading on that path (e.g., a Ricean direct ray, or a pure Doppler path, or a Rayleigh path with Doppler = 0). The direct ray usually falls outside the cluster PAS; therefore the angle of departure is usually different than the cluster AoD.
Range: –30
to 0 dBm
Default:–8.00 dBm
This parameter sets the power ratio between the signal received at a reference antenna oriented to match the polarization of the primary test antenna, and the power received by the same reference antenna in the same orientation, when excited by the cross polarized test antenna.
Range: 0
to 360 degrees
Default: 0 degrees
Sets the RF phase shift for the LOS component in addition to the implicit phase shift due to path delay. This is useful when the direct components, such as direct ray signals, have exactly the same frequency (and therefore, the same phase). In that case, if two equal-amplitude paths have the same delay and phase shift, the power of those two paths summed together is 3 dB higher than the power of two uncorrelated paths summed together or, equivalently, their sum is 6 dB greater than the power of each path individually. If the two paths are 180 degrees out of phase, their sum is zero.
Phase shift includes the effect of path delay. For example, if the RF frequency is 100 MHz, the duration of each 360-degree RF cycle is 10 ns (1/100 MHz). If path delay is 5 ns and the phase shift is set to zero, the actual phase shift would be 180 degrees.
Range: –1600
Hz to 1600 Hz
Default: 0 Hz
For use with the DVB channel model, the parameter sets the path's frequency offset with a minimum resolution of 0.01 Hz. Each path can have a different frequency offset. For a path, the absolute value of the frequency offset plus the Doppler frequency value must not exceed 1600 Hz.
Selects whether to use a log normal distribution of the mean signal power. Log Normal fading, also called "slow fading", simulates the slow changes in signal level due to shadowing by hills or other objects. This is in addition to the currently selected fading type. Selecting Log Normal activates the standard deviation parameters and the decorrelation length. If you select Suzuki as a fading type, the Log Normal parameter is also enabled.
Range: 0 to 12 dB
Default: 1 dB
Sets the standard deviation of the log-normal shadow fading. It is activated when Log Normal is enabled or is implied by Suzuki fading. Changing the standard deviation for one path will change it for all paths.
Range: 1 to 1000 m
Default: 20 m
Sets the decorrelation length (m) for the configured path. Decorrelation length is the average size of objects that cause the shadowing that results in log normal fading. It is activated when Log Normal is enabled or is implied by Suzuki fading. Changing the decorrelation length for one path will change it for all paths.
The following formula determines the rate at which slow fading will occur:
