Receiving process method and receiving apparatus in mobile communication system

A receiving apparatus which receives code channel groups each including code channels from sending apparatuses, said receiving apparatus including an interference canceler which comprises a plurality of stages,

• a first stage of said stages comprising:
• a data modulation estimation part and a channel estimation part for estimating data modulation and channel variations for each received code channel which is a subject for interference canceling;
• a multiplier for multiplying an estimated data modulation signal by an estimated value of channel variations;
• and
• a received spreading signal sequence generation part for obtaining a received spreading signal sequence for each multipath by performing spreading a received signal by using a corresponding spreading code;
• a stage after said first stage in said stages comprising:
• an other channel multipath interference canceling part for subtracting received spreading code sequences of other code channels obtained in the previous stage from received signals for each received code channel which is a subject for interference canceling;
• an own channel multipath interference canceling part for subtracting received spreading signal sequences of own code channels obtained in the previous stage corresponding to a path which is a subject for demodulation;
• a part for preparing signals corresponding to the number of multipaths obtained by subtracting received spreading signal sequences from received signals by said other channel multipath interference canceling part and by said own channel multipath interference canceling part, and updating estimated values of data modulation and channel variations by using said prepared signals;
• a received spreading signal sequence updating part for updating received spreading signal sequences on the basis of updated estimated values of data modulation and channel variations;
• a last stage in said stages comprising a data demodulation part for demodulating data by using signals obtained by subtracting received spreading code sequences obtained in the previous stage from received signals for code channels to be demodulated.