Parallel interference cancellators have been used gradually because of their better performance and lower complexity

for example

in 3G demo systems of Japan.The approaches of regenerating interference and structures of parallel interference cancellators must be adjusted for the sake of small spread factors of 3G systems.Aiming at the question of interference regeneration of multistage non-linear parallel interference cancellators with small spread factors for frequency selective Rayleigh fading CDMA systems

we propose a concept of attenuation factors

reasons and a novel scheme of multistage non-linear parallel interference cancellation (PIC) based on attenuation factors.Moreover

we analyze in detail the performance of multistage non-linear PIC with small spread factors

which benefits from attenuation factors.And simulation results show that to what extent the performance of the novel multistage non-linear PIC based on attenuation factors can be improved.