Using the Communications Blockset with MATLAB (Getting Started)

Getting Started

Analyzing Signal and Error Data

You can use MATLAB to analyze the data from a simulation. For example, to identify the differences between the transmitted and received signals, type

```
diffs=Tx~=Rx;
```

The vector diffs is the XOR of the vectors Tx and Rx. A 1 in diffs indicates that Tx and Rx differ at that position.

You can determine the indices of frames corresponding to message words that are incorrectly decoded with the following MATLAB command.

```
error_indices=find(diffs);
```

A 1 in the vector not_equal indicates that there is at least one difference between the corresponding frame of Tx and Rx. The vector error_indices records the indices where Tx and Rx differ. To view the first incorrectly decoded word, type

```
Tx(:,:,error_indices(1))
```

To view the corresponding frame of errors, type

```
errors(:,:,error_indices(1))
```

You can analyze this data to determine the error patterns that lead to incorrect decoding.

Viewing the Signal and Error Data in the Workspace Running Simulations from the Command Line