Gaussian FIR pulse-shaping filter design
h = gaussdesign(bt,span,sps)
Specify that the modulation used to transmit the bits is a Gaussian minimum-shift keying (GMSK) pulse. This pulse has a 3-dB bandwidth equal to 0.3 of the bit rate. Truncate the filter to 4 symbols and represent each symbol with 8 samples.
bt = 0.3; span = 4; sps = 8; h = gaussdesign(bt,span,sps); fvtool(h,'impulse')
bt— 3-dB bandwidth-symbol time productpositive real scalar
Product of the 3-dB one-sided bandwidth, in hertz, and the symbol
time, in seconds. Specify this value as a positive real scalar. Smaller
bt produce larger pulse widths.
span— Number of symbols3 (default) | positive integer scalar
Number of symbols, specified as a positive integer scalar.
sps— Samples per symbol2 (default) | positive integer scalar
Number of samples per symbol period (oversampling factor), specified as a positive integer scalar.
 Rappaport, Theodore S. Wireless Communications: Principles and Practice. 2nd Ed. Upper Saddle River, NJ: Prentice Hall, 2002.
 Krishnapura, N., S. Pavan, C. Mathiazhagan, and B. Ramamurthi. "A baseband pulse shaping filter for Gaussian minimum shift keying." Proceedings of the 1998 IEEE International Symposium on Circuits and Systems. Vol. 1, 1998, pp. 249–252.