Transmission Performance Improvement by Non-Linear Distortion Noise Power Control in Multi-Band Systems

This paper proposes a non-linear distortion noise power control method with bandwidth control for multiple frequency band transmission which simultaneously uses plural frequency bands in wireless communication systems. The control method employs clipping and filtering, and generates out-of-band noise reduction signals using a part of used signal bands to reduce harmful interference in a primary existing system which shares frequency bands with the multi-band system. The improvement of Signalto- Noise Ratios (SNRs) in the bands used by the primary system is evaluated by computer simulations. The simulation results show that the proposed method at the band use rate of 50 % can improve them by 15 dB at the receiving power ratio of -30 dB to the spectrum sharing multi-band system.