Structural block diagram details

[easewkx]

Hello author, I would like to ask why this place in the picture is not t but T-1, maybe I do not understand it properly, I hope you can answer it for me, which is very impressiveimage

[SongTang-x]

Hello, your understanding is correct, it should indeed be t, not t−1. Thank you for your attention to detail in pointing out this error.