I'm trying to test an equalizer against group delay distortion of a satellite communication link. According to the CCSDS standards, It is agreed to simulate high-order modulation system with in-band group delay variation of corresponding to 10% of the symbol duration. Suppose filtering is done by a very basic low-pass FIR filter with a Z-transform h(z):
- How can the group delay variation be included in h(z)?
- Following , how can it be implemented in gnu radio?