Page tree
Skip to end of metadata
Go to start of metadata

Viewing Output

In this section, you will learn about:

  • How to read and filter your calculation results
  • The available tools to analyze 2-D (plotted) and 3-D (field display) results

Following an EMPro calculation, the results may be reviewed in the Results workspace window. The results that are available in this window depend on the characteristics of the project such as discrete sources, sensors, external excitations, and other project criteria specified in the Simulations workspace window.

This section details the review of results available in this window. Some results will be in the form of numerical values. These are typically single-frequency results performed with a near-zone source. Other results will be displayed in the form of plots. There are several types of plots available to view results based on whether they are time-dependent, frequency-dependent, or angle-dependent. Finally, some results will be available to review as colored field displays. Broadband results collected by Surface sensors and Solid sensors are viewed as individual "Field Snapshots" or "Field Sequences" (strings of snapshots). Three-dimensional far-zone fields may also be available for view depending on simulation criteria.

Results Workspace Window

The Results workspace window

The Results workspace window stores all of the data collected by the Sensors during the calculation. Once the simulation is queued for calculation, the project will be listed in this window so that the results can be viewed. Additionally, the results of any other saved project can be loaded by pressing the List Project button in the upper-left of the dialog. This makes it possible to view and compare the results of multiple projects without having to load several projects individually. Similarly, the results of any project may be closed by selecting the project and clicking the Unlist Project button.

While the calculation progresses, several options may be selected to control how data is refreshed in the Results workspace window as more and more results become available. The list of results in the workspace window may be manually updated by selecting the Refresh button. The list will be automatically updated if Auto-Update Results check box is selected. This check box will also automatically update plotted data when the specific plot window is opened as the calculation progresses.

Filtering Data Results

It is possible to filter the data within the Results workspace window by searching or by categorizing. The Search box in the top right corner enables you to to search for the name of any field or data visible within the window. The results will automatically appear in the list below.

The user is also able to customize the four columns at the top of the window, which filter data according to the specified categories. The column headings are controlled by right-clicking on any of the current column headings and selecting one of the available categories. Each category is described in the table below.

Data Filtering Options

Data Filter

Description

Project Id

Displays the EMPro project ID, which references the location of the loaded project in the file directory.

Project Name

Displays the project name indicated by the user.

Simulation Id

Displays the simulation ID that refers to the simulation's location in the file directory.

Simulation Number

Displays the simulation number that is automatically generated based on how many simulations have been created in a specific project.

Simulation Name

Displays the simulation name specified in the Simulations workspace window.

Run Id

Displays the run ID which references the location of the run in the file directory. Multiple runs are created in the case that a simulation collects data for more than one variable or location (i.e., during parameter sweeps, multiple ports, etc.).

Run Number

Displays the run number.

Result Type

Filters results by type. Any of the following results may be viewed depending on the project, simulation criteria, and the type of data that was requested:
 

Electric Field (E)
Magnetic Field (H)
Conduction Current (Jc)
Magnetic Flux Density (B)
Poynting Vector (S)
Voltage (V)
Current (I)
Impedance
Available Power
Input Power
Instantaneous Power
Feed Loss
Reflection Coefficient
S-Parameters
SAR (Specific Absorption Rate)
Maximum SAR Value
Average SAR in Exposed Object
Average Power
Net Input Power
Net Feed Loss
Net Available Power
System Efficiency
Radiation Efficiency
Dissipated Power
Dissipated Power in Tissue
Dissipated Power in Non-Tissue
Dissipated Power per Material
Radiated Power
Dissipated Power per Electric Material Component
Dissipated Power per Magnetic Material Component
Dimension (time, position, etc.)
Axial Ratio
Radar Cross Section
Gain
Voltage Standing Wave Ratio (VSWR)

OUTPUT OBJECT

Filters results according to its Output Object , which refers to a specific sensor by name.

DATA TYPE

Filters results according to the type of sensor that collected the data. The sensor is referenced by its general type, rather than by its user-defined name (Refer to Output Objects for filtering data by sensor name). The following is a comprehensive list of the sensors that may be listed within this filter:
 

Point Sensor - Retrieves data from any Point sensor in the project.
Surface Sensor - Retrieves data from any Surface sensor in the project.
Solid Sensor - Retrieves data from any Solid sensor in the project.
Far Zone Sensor - Retrieves data from any FAR ZONE sensor in the project.
Raw SAR Sensor - Retrieves raw SAR data.
Averaged SAR Sensor - Retrieves averaged SAR data.
Circuit Component - Retrieves data from a Ciruit Component
HAC Sensor - Retrieves hearing aid compatibility data from HAC sensors.
System - Retrieves ambient result data (not associated with a sensor object).
External Excitation - Retrieves data on the External Excitation waveform.
Raw Steady-State Far-Zone Data - Contains information which can be used to generate new steady-state far zone patterns after a simulation is run.

 

Project:  Simulation : Run

Displays the Project, Simulation, and Run name in one column.

Domain

Filters data according to Time, Frequency or Discrete Frequencies domains.

Field Type

Filters data according to total-field or scattered-field.

Status

Displays whether a result is complete or still being calculated while the simulation is running. This status can be refreshed manually by pressing the Refresh button or automatically by selecting Auto-Update Results .

Misc

Displays query-specific information. For example, for the circuit component voltage when collecting S-Parameters, it could contain the active port. For S-parameters, it could contain the S number or simply the active port. For System numbers, it could contain the number (such as efficiency) or net input power.

Viewing Numerical Results

When a single-frequency calculation has been performed with a near-zone source (voltage or current), parameters such as input impedance, S-parameters, VSWR and the reflection coefficient are displayed as numerical values rather than as line plots since the data only is relevant for the input frequency. Other numerical values are collected by means of a system sensor, which is automatically present in every EMPro project.

Numerical Data Collected by EMPro

Results Displayed as Numerical Data

Sensor Type

Time Dependence

Result Type

Port Sensor

Single-Frequency

Available Power

 

 

Current

 

 

Impedence

 

 

Input Power

 

 

Reflection Coefficient

 

 

S-Parameters

 

 

Voltage

 

 

VSWR

System Sensor

Single-Frequency

Dissipated Power

 

 

Dissipated Power in Non-Tissue

 

 

Dissipated Power in Tissue

 

 

Dissipated Power Per Electric Material Component

 

 

Dissipated Power Per Magnetic Material Component

 

 

Dissipated Power Per Material

 

 

Net Available Power

 

 

Net Feed Loss

 

 

Net Input Power

 

 

Radiated Power

 

 

Radiation Efficiency

 

 

System Efficiency

Impedance

All input impedances are calculated by the ratio of the complex V over complex I for the FDTD mesh edge at the port location. The sign convention is positive for power flow into the antenna or other structure. Thus for a port which delivers power to the antenna, the impedance will have a positive real part, and for a port which absorbs power from the antenna, the impedance will have a negative real part.

When only one active port is present, the feed point impedance at that port is the self-impedance at that port. If more than one port is active, the port impedance values listed represent the ratio of the complex voltage and current at each port including the effects of the sources at all active ports. Thus these impedance values are not the self-impedances at each port, but rather terms of an impedance matrix.

S-Parameter Calculations

When an S-parameter calculation is made with the steady-state far-zone transformation selected, then both the steady-state antenna data and the S-parameter data will be displayed. This may be useful, for example, when making calculations for a microstrip antenna when both S11 and input impedance are of interest.

Net Available Power

The available power is calculated as the total power delivered by the active port or ports into a matched load.

Radiated Power

The radiated power is computed as the difference between the total net input power delivered by the active ports and the dissipative losses from conductive materials and resistive loads in inactive ports.

System Efficiency

The system efficiency is calculated as the ratio of radiated power to available power. Thus, it includes radiation efficiency and mismatch efficiency.

Power Scaling Factor

When viewing single-frequency results collected by the system sensor, the user can specify a scaling factor of the available power to the calculation and determine the scaled result. The absolute input power can be adjusted as desired or an overall scaling can be applied. For example, if the user wanted to know what the output power would have been with an input of one mW, they can enter this value in the available power (will be subject to mismatch loss) or in the net power (after mismatch loss) to see the overall effect. Similarly, any of the output results may be scaled to determine the effect on input and output. Clicking reset will return the values to the un-scaled state.

Input power, Input Impedance, and Loss

When making calculations that include the input voltage, current and/or power in the calculation formulas, such as antenna gain or input impedance, the input voltage, current and/or power will be that provided at the terminals of the mesh edge. Referring to the following figure, the impedance at the port would be the (complex) mesh edge voltage V divided by the (complex) mesh edge current I. The complex values would be obtained from an FFT for a broadband calculation or from two samples of the voltage and current (electric and magnetic fields at the port mesh edge) for a sine wave excitation. If the port is delivering power, then the impedance at that port will have a positive real part. If the port is absorbing power, then the impedance at that port will have a negative real part and the input power will be negative. This is determined by the direction of current flow and voltage polarity for the FDTD mesh edge.

Feed schematic, including FDTD mesh edge voltage, V, and current, I

Active ports (those with active voltage or current sources) are treated differently than inactive ports for some calculations. For an antenna calculation, the input power to the antenna is the algebraic sum of all powers delivered by active ports. Power absorbed by active ports will not reduce the antenna efficiency; however, power absorbed by inactive ports will reduce antenna efficiency.

To clarify this, consider two different situations. An antenna composed entirely of perfect conductor includes 2 ports, the first containing a 1-V source and a resistor, the second a passive port containing only the resistor. Assuming that some current flows in the passive resistor, the antenna efficiency will be less than 100%. If we repeat the same calculation, but with a 0.00001-V source added to the formerly passive port, and with both sources set active, the antenna efficiency will now be calculated as 100% even though the 0.00001-V source will have negligible effect on the antenna currents and radiation. This discrimination is done so that active ports may utilize lumped circuit elements to match to an antenna without changing the antenna efficiency, impedance, and gain, while passive elements may be added to an antenna with their effects included in the antenna efficiency and gain results.

Similarly, for input impedance calculations, the source resistance, capacitance and inductance values will not be included in the input impedance. For example, the input impedance of an antenna as calculated using EMPro should not change regardless of any changes in the active port components (source/R/L/C). This is as it should be, since the antenna impedance is a function of the antenna geometry/materials and not of how the antenna is fed.

Viewing 2-D Plotted Results

Some results are viewed as 2-D plots. There are three basic categories of plots in EMPro, depending on the X -axis (abscissa) type:

  • XY PLOTS - visualizes data in a Cartesian coordinate system.
  • POLAR PLOTS - represents data with an angle-independent axis.
  • SMITH CHARTS - displays complex data vs. frequency, such as S-parameters and reflection coefficient.

The 2-D plots are viewed by right-clicking on the desired result type in the Results workspace window and selecting Create Line Graph, as seen in the following figure.

Results right-click menu

Before the graph is displayed, the user has the option of adjusting the graph properties such as the component, data transform, and complex part. The Target Graph option enables you to view and edit plots that were previously created (from the same data selected in the Results window).

The following figure shows samples of the create graph dialog for each plot.

Create graph dialog for XY, Polar, and Smith plots

For all calculations, the most important quantities are the time-domain plots of the fields in the problem space. Always perform a quick review of these values to ensure that a calculation has converged. Without convergence, most other results will be meaningless, particularly any plots converted to the frequency domain such as S-parameters or impedance.

Note

Note that input impedance and S-parameters may be plotted in rectangular form vs. frequency or as a Smith chart.

Results Displayed as Plotted Data

Plotted Data Collected by EMPro

Sensor Type

Time Dependence

Result Type

Port Sensor

Broadband

Current

 

 

Impendence

 

 

Input Power

 

 

Instantaneous Power

 

 

Reflection Coefficient

 

 

S-Parameters

 

 

VSWR

Point Sensor/Surface/Volume

Broadband

E-Field (E)

 

 

H-Field (H)

 

 

B-field (B)

 

 

Conduction Current (Jc)

 

 

Poynting Vector (S)

System Sensor

Broadband

Net Feed Loss

 

 

Net Input Power

Far Zone Sensor

Broadband

Radar Cross Section

 

 

Gain

 

 

E-Field (E)

Far Zone Sensor

Single-Frequency

Radar Cross Section

 

 

Axial Ratio

 

 

E Theta, E Phi

 

 

Circular Polarization

 

 

Ludwig-2 Az, El

 

 

Ludwig-2 Al, Ep

 

 

Ludwig-3

Far Zone Post Processor

Single-Frequency

E-Field (E)

Customizing Plots

There are several ways to customize plotted data after it is opened from the Results workspace window. The following sections detail the various tools that are available to modify plotted results.

Note

Keep in mind that the tools available within the plot window depend on the type of graph you are viewing (i.e., XY Plots, Polar Plots, or Smith Charts).

Export Data

Select this option to export graphical data point values to a text file in a specified directory.

Export Image Tool

Select this icon to save an image of the current plot to a specified directory.

Pan Tool

Select this tool, and drag the mouse within the plot to pan to the desired view of the plot. Press the |Ctrl| key and drag to pan along the independent axis. Press the |Shift| key and drag to pan along the dependent axis.

Zoom Tool

Select this tool to zoom-in and to zoom-out of the plot. The mouse wheel as well as the right and left mouse buttons, can be used to perform zoom operations as described below.

Using mouse-wheel:

Roll the center wheel of the mouse forward to zoom-out of both axes simultaneously.
Press |Ctrl| and roll the center wheel forward to zoom-out of the independent axis.
Press |Shift| and roll the center wheel forward to zoom-out of the dependent axis.
Roll the center wheel of the mouse backward to zoom-in to both axes simultaneously.
Press |Ctrl| and roll the center wheel backward to zoom-in to the independent axis.
Press |Shift| and roll the center wheel backward to zoom-in to the dependent axis.

Using mouse buttons:

Right-click and drag the the mouse anywhere in the plot window to zoom-out of both axes simultaneously.
Press |Ctrl| and right-click/drag to zoom-out of the independent axis.
Press |Shift| and and right-click/drag to zoom-out of the dependent axis.
Left\click and drag to define a rectangular view-window in the plot window to zoom-in to both axes.
Press |Ctrl| and left-click/drag to zoom-in to the selected domain of independent axis values.
Press |Shift| and and left-click/drag to zoom-in to the selected range of dependent axis values.

Legend Visible

This button toggles the display of the legend within the graph.

Graph Properties Tool

The following illustration highlights the three tabs that are available for editing the properties of any graph in EMPro. Each tab is detailed below.

Tabs available for editing graph properties

Title properties

Define the graph name and title as well as the background color of the graph in this tab. A checkbox also toggles the legend display on and off. This tab is displayed in the figure above.

Axes properties

Define the title of the axes and the limits of the axes in this tab. The Auto checkbox may be selected to auto-select these limits.

Note

If a graph only contains continuous data, the X -axis must be specified (this will not happen automatically).

The Units drop-down menu is used to specify the units and to apply a log scale if necessary.

For certain Smith plots, you will also have the option of modifying the Reference Impedance.

The figure below shows the axes properties editor for a 2-D XY graph.

Editing the axes of graphs

Plot properties

Define the characteristics of the plotted lines in this tab. A list of every dependent variable is listed with a customizable line color, line width, and line style. Any unwanted variables can also be deleted in this tab.

Selection tool

Select this tool to move, delete, or edit a marker's properties. To move a marker, click on the marker with the selection tool (once selected, it will turn yellow) and roll the mouse-wheel forward or backward to move an attached marker along its plot. Pressing |Ctrl| and rolling the mouse-wheel will speed up the movement of the marker.

To delete any marker, simply select the unwanted marker, right-click and press Delete Marker . All markers may be deleted at one time by right-clicking anywhere in the plot area and choosing Delete All Markers .

To edit a marker's properties, click on the desired marker so that it turns yellow, then right-click and select Marker Properties . A window will appear with several different editing options. The location coordinates of the marker can be adjusted by manually typing in the desired values in the Requested Location section of the dialog box.

Marker properties dialog

Note

If the coordinate box you desire to edit is disabled, select the appropriate option in the Attached plot drop-down menu.

The marker may also be attached to a particular plot by selecting its name in the Attached Plot drop-down menu and selecting an Interpolation Method for EMPro to use in order to place the point. Depending on this definition, the marker will be shifted to the nearest point on the selected function or linearly interpolated based on the independent axis that is entered by the user in the Requested Location dialog box. Finally, the type of marker can also be redefined in this editor window in the ) Type drop-down list.

Additionally, this tool can be used to move or close the legend in the graphical space. (Any tool, however, can be used to perform this function.)

Select this tool by clicking on its icon or select it from the Markers menu, as shown in below.

Marker drop-down menu

Point Marker Tool

Select this tool to mark any point on the plot by clicking on the desired marker location. A marker with the location coordinates will appear above the point, depending on the type of plot:

  • XY Plot: (X -location, Y -location)
  • Polar Plot: (radius, angle)
  • Smith Plot: (real part of location, imaginary part of location, frequency)

When the mouse moves close to the plotted curve, it is snapped to the closest location on the interpolated line or sampled point. Holding the |Ctrl| key will disable the snapping action, allowing a point to be placed anywhere. Holding the |Shift| key will snap the marker to sampled points only. Note that markers placed on sampled points are blue, and markers placed on interpolated points are black.

Crosshair Marker Tool

Select this tool to mark the location of a single point by two intersecting cross-hairs. The marker is placed at the right edge of the plot. (Snapping actions are the same as the Point/Tracker Marker described above.)

The following figure shows an XY Plot with a Crosshair Marker (1.8873e-08 s, -6.0381e-06 A) and Point Marker (1.4636e-08 s, 1.0573e-05 A).

2-D XY graph with Crosshair and Point markers (highlighted in red)

The figure below shows a polar graph with a Crosshair Marker along a radius.

Polar graph with Crosshair marker (highlighted in red)

The following figure shows a smith graph with a Crosshair Marker along a radius.

Smith graph with Crosshair markers (highlighted in red)

Vertical Marker Tool

Select this tool to place a vertical line that intersects with the X -axis. The marker (Y = constant) will be placed along the top-edge of the plot area. (Snapping actions are the same as the Point/Tracker Marker described above.)

Horizontal Marker Tool

Select this tool to place a horizontal line that intersects with the Y -axis. The marker (X = constant) will be placed along the right-edge of the plot area. (Snapping actions are the same as the Point/Tracker Marker described above.)

The figure below shows a 2-D XY Graph with a Vertical Marker (at X = 1e-08 s) as well as a Horizontal Marker (at Y = 1.5e-05 A).

2-D XY graph with Vertical and Horizontal markers (highlighted in red)

3-D Field Displays

Colored 3-D field displays may be viewed in slices of the geometry by saving either broadband or single-frequency field quantities. The fields may be viewed in with the geometry (solid or meshed), or by themselves.

Three types of fields may be viewed with the geometry:

  • Time Domain Snapshots - available for any calculation as they are simply snap shots of the near-zone fields at specific steps in time.
  • Complex Fields or Derived Quantities (such as SAR) - available at specific frequencies
  • Three Dimensional Far-Zone Fields - can be requested either before the calculation with a far-zone sensor, or after a calculation through post-processing.

Data Collected With Near-Field Sensors

Field snapshots are listed in the field control panel as either single slices or as field sequences. The field sequences are movies of the individual slices as the fields progress with time in a particular slice of the geometry. Depending on what was saved, each field snapshot may have electric and magnetic fields, current densities, Poynting vectors stored for each direction (X , Y and Z ) and a display of the combined magnitude. Field snapshots are collected by surface sensors and solid volume sensors for broadband data.

Note

In order to view single-frequency data, the Collect Steady-State Data check box must be checked in the Simulations workspace window (under the Frequencies Of Interest tab).

Results Plots Available For Each Sensor Type

Sensor Type

Result Type

Time Domain

Discrete-Frequency

Broadband

Point Sensor

E-Field (E)

X

 

X

 

H-Field (H)

X

 

X

 

B-field (B)

X

 

X

 

Poynting Vector (S)

X

 

X

 

Conduction Current (Jc)

X

 

X

 

Scattered E

X

 

X

 

Scattered H

X

 

X

 

Scattered B

X

 

X

 

Average Power

 

 

X

Surface/Solid Sensor

E-Field (E)

X

X

 

 

H-Field (H)

X

X

 

 

B-field (B)

X

X

 

 

Conduction Current (Jc)

X

X

 

 

Scattered E

X

X

 

 

Scattered H

X

X

 

 

Scattered B

X

X

 

 

Poynting Vector (S)

X

 

 

 

Average Power

 

X

 

SAR Sensor

SAR (Specific Absorption Rate)

 

X

 

HAC Sensor

E-Field (E)

 

X

 

 

H-Field (H)

 

X

 

 

HAC max E-Field (E)

 

X

 

 

HAC max H-Field (H)

 

X

 

(Scattered) Electric Fields (E): magnitude, normal, or X , Y or Z components of the (scattered) electric field data at each cell edge.

(Scattered) Magnetic Fields (H): magnitude, normal, or X , Y or Z components of the (scattered) magnetic field data at each cell edge.

(Scattered) Magnetic Flux Density (B): magnitude, normal, or X , Y or Z components of the (scattered) B-field computed from the magnetic fields at each cell edge and the associated permeability for that cell edge.

Average Power Density (SAV): magnitudes of the average power density computed from the electric and magnetic fields at each cell edge.

Conduction Current Magnitude (Jc): conduction current at an electric field cell edge.

SAR (Specific Absorption Rate): computed for each complete cell containing a lossy dielectric with a non-zero material density.

Data Collected with Three Dimensional Far-zone Fields

The Results workspace window also displays the data collected within 3-D far-zone fields. Any 3-D far-zone request generated using EMPro's post-processing engine (run separately from the calculation engine) is automatically added once the post-processing is complete. If steady-state far-zone data is enabled for the sensor, the 3-D results will include the E-field and axial ratio in the discrete-frequency domain. Gain or discrete-frequency radar cross section (RCS) will also be available when using a feed or external excitation, respectively.

Note

Note that the polarization (Theta/Phi, Ludwig-2, etc.) is selected through the Setup tab of the Field Editing Toolbar.

Viewing 3-D Field Displays

EMPro displays 3-D field data in the Geometry workspace window. The following subsections discuss how to configure and analyze the display, using the Scale Bar, the Field Reader Tool, rescaling, and the field editing toolbar.

The Scale Bar

The Scale Bar, located at the top of the Geometry workspace window, "paints" the view with a range of colors which correspond to the range of values displayed. By default, the Scale Bar color palette is shown in continuous mode within a default range of values. You can adjust these properties by right-clicking on the scale bar and selecting Discrete Mode, to change the palette to discrete colors, or Automatic Range, to change the range of values to that which is actually present.

There is also a Properties option under the right-click menu. Clicking this will bring up the Scale Bar Editor. Using this editor, you can manually set the Scale Bar limits, units and colors to your preference. Take note of several settings that may not be intuitive for the first-time user:

  • Under the Limits section, it is possible to "clamp" values outside the defined scale bar limits to the nearest color. This makes it possible to view outliers that otherwise would not be colored with the Scale Bar.
  • Under the Scale section, when Relative dB is selected, you can define its reference value or use the value automatically selected by EMPro.
  • Checking Use Discrete Colors makes it easier to view contours in the 3-D results.
  • Font Color and Background Color change the colors of the Scale Bar itself, not the coloration of the results.

The following two figures show the Scale Bar Editor, and the Scale Bar_ with the Field Reader tool.

The Scale Bar Editor

The Field Reader Tool

The Field Reader Tool is located in the toolbar to the right of the Geometry workspace simulation space. After selecting this icon, wheel the mouse over the geometry object to identify its field values. A marker in the Scale Bar will display the nearest known field value to the location of the mouse. This location is represented by a small dot on the screen.

The Field Reader tool

Rescaling

In the Results workspace window, filter the results by the output object System. Double-clicking on results such as Dissipated Power or System Efficiency will open the System Sensor Output dialog box. Changing any value in this table will rescale the other values shown.

Note

The Show Scaled Values box must be selected to enable editing in the System Sensor Output dialog box.

  • Scaling only affects results which are in the discrete frequencies domain.
  • When you change the scaling by editing values in the System Sensor Output dialog, you only scale the results for that particular calculation engine run at that particular DFT frequency. Any other tables of data and plots associated with this run and frequency will also be affected.

The Field Editing Toolbar

Located at the bottom of the Geometry workspace window, the field editing toolbar is used to configure the properties of the view. In the upper-left corner of this toolbar, a drop-down list will display any view that you have opened from the Results window. You can use the Hide Others and Unload buttons to single out certain view(s) if necessary. The following figure shows a drop-down list of such results in the field editing toolbar.

The results drop-down list of the field editing toolbar

The tabs and configuration options below will change depending on the active view. A comprehensive list of the available options are described below.

The Setup Tab

There are two main configurations for the Setup tab, depending on the type of sensor you are evaluating.

  • Keep in mind that not all fields listed will be available for every view.

Surface, Solid SAR Sensor Configuration

  • Sequence Axis - Select the axis along which to view the sequence (from the Sequence tab).
  • Display Mode - The available display modes are Vector Field, Point Cloud, Flat, and 3D.
  • Size Factor - Used to scale the size for point clouds and vector display modes
  • Displayed Field - Lists the available components of a vector field that can be shown in a plot.
  • Decimation - Used to sample a subset of points for solid sensors
  • Surface Resolution - Used to sample a subset of points for Surface sensors. This control is only available if the Surface sensor sampling method is configured as Field Interpolation.
  • Complex Part - Used to single out real/imaginary/magnitude values for single-frequency data
  • Axis Ranges - Set the independent axis during the sequence
    • Axis - defines the axis
    • Full - runs along the full range of the axis
    • Min And Max - subsets non-sequence axes
  • Enable Scaling - enable the scaling factor
    The Setup tab for a solid sensor configuration

Far-Zone Sensor Configuration

  • In the first section, set up your viewing preferences.
    • Viewing - choose among the available result types
    • Complex Part - view the Magnitude, Real, or Imaginary part of the results.
    • Size - enter the size of the maximum radius.
  • In the second section, choose the orientation of the Center point.
    • Enter the (X, Y, Z) coordinates of the center, or
    • Choose the center using the Pick tool.
    • The Reset Center On drop-down enables you to center the plot at the center of the
      geometry or at the location of any of the ports in your active project.
  • Select the following viewing options:
    • Display Axes Theta/Phi
    • Display Main Lobe Direction (the direction of maximum gain)
    • Show Scaled Values
      The Setup tab for a far-zone sensor configuration

The Sequence Tab

This tab is available when viewing an SAR, Solid, or Volume sensor. Configure the settings here to "play through" a simulation.

  • Minimum/Maximum - values entered here set limits on the range of the sequence axis.
  • Showing - shows the currently plotted value of the sequence axis.
  • The scroll bar at the bottom of the window can be used to view any point along the sequence.
  • The simulation buttons enable you to move through the sequence:
    • The forward and back buttons play the sequence forwards and backwards, respectively.
    • The pause button pauses a playing sequence.
    • The fast forward and rewind buttons fast forward and rewind the sequence, respectively.
    • The jump forward and jump backward buttons jump to the end or beginning of the sequence, respectively.
  • Compute Bounds - when this box is checked, EMPro will compute the bounds during the sequence.
  • - performs the Compute Bounds calculation
  • The Advanced tab
    • Checking the Auto-Repeat Sequence box will automatically replay the sequence continuously.
    • The Step Size determines the number of indices to change for the simulation buttons.
      The Sequence tab of the field editing toolbar

The Rotations Tab

The Rotations tab, shown in Figure 13.20, oers several operations to adjust the orientation of the far-zone results by setting the Up Vector of the view. Changing the Up Vector (which is the Z-axis by default), will set the reference point for the spherical coordinate systems (e.g., theta/phi, alpha/epsilon, etc.) This affects field plots of single polarization components, partial power effciency and power computations, mean eective gain computations, and antenna diversity. This is useful in
cases where the geometry is aligned with an axis of the computation grid, but the real-world position of the geometry is not axis-aligned.

  • The Up Vector Presets list enables you to select a pre-defined Up Vector in the X-, Y-, or Z -direction.
  • The Pick Up Vector tool enables you to click and drag within the simulation space to create your own Up Vector.
  • The Undo button will undo an operation.
  • The Redo button will redo an operation.
  • The Reset button will reset the Up Vector.
    The Rotations tab of the field editing toolbar

The PDF Tab

The PDF tab controls the settings used in the computation of mean eective gain and antenna diversity far zone results. The following illustration shows the PDF tab.

  • XPD is cross-polarization discrimination of the incident multipath field. It can be expressed by the ratio of time-averaged vertical power to time-averaged horizontal power in the fading environment. Users can input a linear value or a decibel value.
  • PDF, or Probability Density Function, is used to model communication channels. This function "weights" different directions in the far zone sphere such that certain far zone direction are taken into account more than others in the mean effective gain and antenna diversity calculations. It has a maximum value of one and a minimum value of zero. EMPro provides the following choices for PDF's:
    • Uniform Value: in this case, PDF is simply one.
    • Gaussian: this is most commonly used as a model of channels. Theta Max and Phi Max are the angles of the maximum incoming field. Sigma Phi and Sigma Theta are the standard deviations for the and directions, respectively.
    • User-Defined: this enables you to import a PDF from a text file. The file must contain a grid of theta/phi angles and the corresponding probability density at each angle. For example, to define the PDF at ten theta angles with twenty phi angles, the text file data would look something like the following:

theta0radians phi0radians pdfAtTheta0Phi0
theta0radians phi1radians pdfAtTheta0Phi1
...
theta0radians phi19radians pdfAtTheta0Phi19
theta1radians phi0radians pdfAtTheta1Phi0
...
theta9radians phi19radians pdfAtTheta9Phi19

The PDF tab in Gaussian mode

The Statistics Tab

There are two main configurations for the Statistics tab, depending on the type of sensor you are evaluating.

Note

Keep in mind that not all fields listed will be available for every view.

Far-Zone Sensor Statistics

The next figure shows the Statistics tab for a far-zone sensor configuration.

When selected, Power/Efficiency gives the user the option of choosing from among the following radiation patterns:

• Full Pattern - specifies the use of a full far zone sphere.
• Upper Hemisphere - specifies the use of theta = [0, 90o] and phi = [0, 360o].
• Open Sky - specifies the use of theta = [0, 80o] and phi = [0, 360o].
• Partial Pattern - enables you to specify an arbitrary solid angle. These angles are defined relative to the coordinate system defined under Rotations.

Each pattern will display its statistics to the right. In the case of Partial Pattern, the user can redefine the min and max values of Phi and Theta by typing them in to the corresponding boxes. The statistics will update accordingly.

The Other Statistics option presents a list of additional statistics.

The Statistics tab for a Far-Zone sensor, showing Power/Efficiency and Other

statistics

SAR Sensor Statistics

The next illustration shows the Statistics tab for an SAR sensor configuration.
This tab is available when looking at SAR data for both the SAR Sensor and the SAR Averaging Sensor. The following figure displays the dialog that appears when the View All SAR Stats button is pressed.

  • The SAR Maximum Value displays a max SAR value dependent on the properties of the SAR Sensor, (i.e., the maximum 1-gram Averaged SAR value, the maximum 10-gram Averaged SAR value, or the maximum raw SAR value). A value entered here affects the power scaling for this run and frequency, in the same manner as adjusting the Power Scaling Factor in the System Sensor Output dialog.
  • SAR Maximum at Location displays the global coordinates of the location where the SAR maximum value is found.
  • The Avg. SAR in Exposed Object field is available when looking at raw SAR sensor data only. It displays the whole body average SAR value. An adjustment entered here aects the power scaling in the same way as adjusting the SAR Maximum Value.
  • The View Slice With Max Value button takes you to the planar slice of SAR data which contains the maximum value.
  • The View All SAR Stats button opens a separate window displaying the statistics for the Raw SAR, 1g Averaged SAR, and 10g Averaged SAR together in a table. Through this window, the scaling factor can be adjusted, which affects all SAR values in this window, including data displayed in the SAR Sensor Statistics tab. The scaling factor and SAR statistics values will also automatically update when the user manually changes (rescales) any other statistics available through the Results workspace window, such as power and efficiency values.

Note

For more information on rescaling values in the System Sensor Output dialog, refer to Rescaling.

The Statistics tab for an SAR sensor

The Diversity Tab

The Diversity tab is used to compute antenna diversity metrics between two far zone patterns. To perform the diversity computations, you must load the data for both far zone patterns in the Results workspace. Then go to the diversity tab for one of the two patterns. The following figure shows the Diversity tab.

  • The Pattern 2 drop-down list enables you to select the far zone result which your current far zone result is compared against. The only choices listed here are results which have been loaded into the Results workspace window.
  • The statistics next to From 3D Pattern show the diversity computation for the full far zone sphere. The statistics next to From 2D Pattern show the diversity computation at theta = 90o.
  • Under Diversity Options, you can set the Antenna 1 Phase and Antenna 2 Phase
    controls to specify the phase difference between the two far zone patterns.

    Note

    Note that the XPD and PDF settings under the PDF tab impact this computation, as well as the settings under the Rotations tab.

    The Diversity tab of the Field editing toolbar

The Hearing Aid Compatibility Tab

This tab, as the name suggests, is only available when viewing (HAC) sensors.

  • Frequency - Select the frequency of interest for the hearing aid.
  • Display Mode - The available display modes are Point Cloud and Flat.
  • Show Scaled Values - When checked, the displayed results are scaled by the scaling factor entered by the user on the system sensor output table.
  • Surface Resolution - This option appears whenever there is a HAC or interpolated surface sensor. It controls the resolution at which field data is shown for the sensor. The higher the resolution setting, the more data points are shown on screen (and the closer they are together).
  • M-Rating - Displays the M-rating of the sensor, or the suitability of the hearing aid used with a wireless device. The rating range is 1-4, with 4 being the best rating.
  • Threshold - This is the maximum allowed field value given the current M-rating.
  • Band - Displays the band type. Under the Edit button, you can configure the properties of the band, or define a pre-set list of properties using the Manage Presets button. An editor dialog will appear where you can add a new preset or import presets from a text file. Each line in the file must follow this format:
    • Lines in the file starting with # or ! are comments and are ignored.
    • Otherwise, the line must contain six semicolon-delimited items in this order: name; waveform modulation factor; E-field probe modulation factor; H-field probe modulation factor; articulation weighting factor, in dB (must be either 0 or -5); and a boolean value which determines whether RMS conversion should be used (1 to enable, 0 to disable).

An example of this format is as follows:

! This is a comment
Band 1 Name;0.85;0.9;0.8;-5; 0
Band 2 Name; 1.0; 0.92; 0.33; 0; 1

  • The 3x3 Grid Region - This shows the maximum field values in each of the 9 squares of the HAC grid. The double-line on the top-level of the readout helps you orient in reference to the white grid on the displayed field (it also has a double-line in the top-left corner). Three of the cells in the 3x3 grid will have a dotted red border around them. These are the three cells chosen to be excluded from the HAC rating computation as allowed by the IEEE HAC standard. Also, any cells with red text are cells which exceed the field value threshold amount for the current M-rating.

Post-Processing

Post-processing gives the user the option of running additional computations after the calculation engine run is finished to save certain results to disk. Two types of post-processing are available.

Far Zone Post-Processing

Far-zone post-processing is enabled by checking the Save Data for Post-simulation Far Zone Steady-state Processing box under the Frequencies of Interest: Data Storage tab of the Simulations workspace window. When this configuration is set, there will be an entry for Raw Steady-State Far Zone Data in the Results workspace window. Double-clicking this entry will enable you define a new far zone geometry at which the steady-state far zone pattern will be computed. Edit the geometry exactly as you would edit a far zone sensor. When you click Done in the far zone sensor editor, the computation of the far zone pattern will begin. Once complete, you can find a new result in the Results workspace window which corresponds to the newly defined far zone pattern.

SAR Post-Processing

Right-clicking on any Raw SAR Sensor entry in the Results workspace window will show an option in the context menu to Postprocess Results. This enables you to perform SAR averaging. Edit the geometry and averaging parameters exactly as you would in the SAR Averaging Sensor editor. Once you click Done in the editor, you will be given the option to automatically run the post-processor. If you say yes, the post-processing operation is queued as if you had created a new simulation. Otherwise, you will have to do the post-processing run manually. Once the SAR averaging is complete, new SAR average data will appear in the Results workspace window.

  • No labels