MATLAB: Do I receive an error related to sample times when using the GMSK Passband Demodulator block from the Communications Blockset 2.0 (R12)

Question

When I try to demodulate GSM data using the GMSK Passband Demodulator block from the Communications Blockset 2.0 (R12), I receive the following error:

 Error in block 'demodGMSK/GMSK Demodulator Passband': Block initialization commands cannot be evaluated.  MATLAB error message: Input sample time must be an integer multiple of the product of the Baseband samples per symbol value and the output sample time

Answer 1

This error message indicates that the input sample time must be an integer multiple of the baseband samples per symbol and the output sample time (which is the "symbol period"). This integer multiple condition is a restriction of the Passband Modulators-Demodulators in the Communcations Blockset 2.0 (R12). As of the Communcations Blockset 2.0.1 (R12.1), this is no longer a restriction. Also note that a variable-step solver must be used, as this is a requirement for the digital passband libraries to function appropriately in the Communcations Blockset 2.0.1 (R12.1).