Input Data

This block has between two and four input ports, depending on how you set the dialog parameters. The input ports marked Tx and Rx accept transmitted and received signals, respectively. The Tx and Rx signals must share the same sampling rate.

The Tx and Rx input ports accept scalar or column vector signals. For information about the data types each block port supports, see the Supported Data Types table on this page.

If Tx is a scalar and Rx is a vector, or vice-versa, then the block compares the scalar with each element of the vector. In this case, the block behaves as if you had preprocessed the scalar signal by using the Repeat block with the Rate options parameter set to Enforce single rate.

If you select Reset port, then an additional input port appears, labeled Rst. The Rst input accepts only a scalar signal (of type double or boolean) and must have the same port sample time as the Tx and Rx ports. When the Rst input is nonzero, the block clears and then recomputes the error statistics.

If you set the Computation mode parameter to Select samples from port, then an additional input port appears, labeled Sel. The Sel input indicates which elements of a frame are relevant for the computation. The Sel input can be a column vector of type double.

The guidelines below indicate how you should configure the inputs and the dialog parameters depending on how you want this block to interpret your Tx and Rx data.

Output Data

This block produces a vector of length three, whose entries correspond to:

The block sends this output data to the base MATLAB^® workspace or to an output port, depending on how you set the Output data parameter:

Delays

The Receive delay and Computation delay parameters implement two different types of delays for this block. One delay is useful if you want this block to compensate for the delay in the received signal. The other is useful if you want to ignore the initial transient behavior of both input signals.

Use the Find Delay block to determine the delay, and then set the Receive delay to the delay reported by the Find Delay block.

If you use the Select samples from mask or Select samples from port option, then each delay parameter refers to the number of samples that the block receives, whether the block ultimately ignores some of them or not.

If using the Sel port to calculate errors on a delayed signal, the delay must be added to the Sel indices. For more information, see Calculate Errors for Delayed Selected Samples.

Stopping the Simulation Based on Error Statistics

You can configure this block so that its error statistics control the duration of simulation. This is useful for computing reliable steady-state error statistics without knowing in advance how long transient effects might last. To use this mode, check Stop simulation. The block attempts to run the simulation until it detects the number of errors the Target number of errors parameter specifies. However, the simulation stops before detecting enough errors if the time reaches the model's Stop time setting (in the Configuration Parameters dialog box), if the Error Rate Calculation block makes Maximum number of symbols comparisons, or if another block in the model directs the simulation to stop.

To ignore either of the two stopping criteria in this block, set the corresponding parameter (Target number of errors or Maximum number of symbols) to Inf. For example, to reach a target number of errors without stopping the simulation early, set Maximum number of symbols to Inf and set the model's Stop time to Inf.

Tuning Parameters in an RSim Executable (Simulink Coder Software)

If you use the Simulink Coder rapid simulation (RSim) target to build an RSim executable, then you can tune the Target number of errors and Maximum number of symbols parameters without recompiling the model. This is useful for Monte Carlo simulations in which you run the simulation multiple times (perhaps on multiple computers) with different amounts of noise.