Communications Toolbox Graphical User Interface Example



You can type commgui to open the graphical user interface (GUI) example. This example provides a simple tool for you to compute bit-error-rates using different combinations of different methods. This help file briefly describes how to use the tool.
General Information
Load/Save Window Parameters
Define Computation Parameters
Start Computation
Manage Computed Data

Go to the tutorial for Communications Toolbox

This is commfunc.html file.


Glossary of COMMGUI:
Err-Ctr: Error Control;
Bit-Err Rate: Bit Error Rate;
S/N Ratio: Signal/Noise Ratio



Communication Toolbox GUI Example General Information

General Information

The graphical user interface (GUI) example illustrates how to use the Communications Toolbox to compute the bit-error-rate. The example uses MATLAB functions in sources and sinks, error-control coding, modulation, and channel categories. The computation is based on the parameters provided in the data entry slot. In the GUI window, all white areas are designed for data input.

You can define your own computation by choosing my own in the GUI window. To be able to run your algorithm, you need to edit the file commod.m.



Load/Save Window Parameters for Comm Toolbox GUI Example

Load/Save Window Parameters

The File menu at the top of the GUI window enables you to load and save the parameters defined in this example. The saved data includes the parameters of the computation methods, the resulting computation data, and the curve fitting order. The file commfoo.mat in the comm directory of the Communications Toolbox is an example of the saved data.

The Load setup and Save setup selections in the File menu uses a browser file system to help you access your directory (folder) and files.



Define Computation Parameters in the Communications Toolbox GUI Example

Define Computation Parameters

The GUI window is divided into two sections: the upper section for parameter entries and the lower section for displaying the computed data. The computation goes through the stages of
Source Data
Error Control Coding
Modulation
Channel
Demodulation
Error Control Decoding
Save Data
The first parameter in the channel category can be a vector. The vector length determines the computed data length. When you use the random integers in the Source category, the data length can be a scalar or a vector. The vector length must match the length of the first parameter in the channel. When you use a workspace variable as an input source, the workspace variable can be a column vector, or a matrix with its column number the same length as the first parameter in the Channel category.

You can view the help for the functions encode and decode to find the definition of the error-control coding parameters.

You can view the help for the functions dmod and ddemod for the passband modulation/demodulation simulation parameters. You can view the help for the functions dmodce and ddmodce for the baseband modulation/demodulation simulation parameters.

If you don't know how to choose a parameter, leave the parameter entry empty. The example will fill in a default parameter for you.



Start Computation in the Communications Toolbox GUI Example

Start Computation

After defining the parameters, you can click the Run button to start the simulation. There are two indicators that appear between the upper and lower sections of the GUI wich show the computation stages. A textual indicator in the center shows which computation category is being processed. The categories are:
Source Data
Error Control Coding
Modulation
Channel
Demodulation
Error Control Decoding
Save Data
There is also a status bar that runs across the width of the GUI and shows the percentage of the computation completed. The percentage is the ratio of the completed computation stages to the total number of computation stages.

The computed data is stored in the Current Data storage area. The data contains SNR, the signal to noise ratio, and bit_err_ratio, the bit error ratio.



Managing Computation Data in the Communications Toolbox GUI Example

Manage Computation Data

The GUI window provides one sub-window for the storage of your current running result and four sub-windows for the storage of your data comparison. You can move the data to any one of these sub-windows by simply dragging from others. You can also import the data from Matlab workspace variables. You can also export the data to Matlab workspace variables.

To get the plot for error rate estimation, choose the curve fit order and press PLOT button. It will compute the data that you have in the sub-window by the current curve fit order and plot the results in a new window. To see the comparison, just select any one of the sub-windows you need and it will only plot the selected data.

Note that after you have dropped the data into the trash can, the data will be deleted from the window. There is no undo.