Channel estimation is a key technique in the field of mobile communications.Especially

with the demand of next generation mobile communications

the channel estimation theory in the high data rate and high speed mobile environment will become a dominant technique in mobile communications.This paper presents a novel method named Channel Estimation by using Two Orthogonal Channels (CETOC) method applied to high data rate and high speed mobile communications.This method can effectively overcome influence resulted from fast fading by using the joint estimation of two independent orthogonal channels

so it is possible to use high-dimensional modulation in fast fading channel.