“However it is not implemented by vendors YET, because it is not really useful”.
I can understand that it may not be useful for vendors.But I think it operators will love to have such feature.Why?…..
Let us say that if vendor implements any feature which is going to benefit operator in such a way that operator can reduce the
purchase of hardware then……this picture will be good for operator and bad for vendor.
A BTS site with GMSK = 10 TCH
A BTS site with 8-PSK= 30 TCH
Thus We need three BTS sites with GMSK and one BTS site with 8-PSK to offer same number of traffic.
I think vendors do have some influence over the 3GPP or like.