A method, apparatus, and radio receiver system for canceling multi-user interference in a single-carrier radio communication system. A front-end receiver such as a RAKE receiver receives a radio signal formatted in a sequence of frames, and outputs a plurality of user signals. A processing selector selects on a frame-by-frame basis, either a first signal processing chain that serially decodes and removes the interference contributions of the user signals, or a second signal processing chain that simultaneously decodes and removes the interference contributions of the user signals in parallel. The processing selector may select the first signal processing chain when the number of user signals is greater than or equal to a threshold value, and may select the second signal processing chain when the number of user signals is less than the threshold value.