Hi Marcella,
This error typically occurs with the OSTBC Encoder when the input data does not meet the expected dimensional requirements. The input port of the OSTBC Encoder block requires input data to be specified as a column vector or matrix of values with power-of-two slope and zero bias. It seems the input you are providing might not be a column vector, which could be causing this issue.
For more information about input data dimensions and the Input-to-Output Dimensions for the OSTBC Encoder, you can refer to the following documentation:
