A New Multipath Interference Mitigation Technique for High-Speed Packet Transmission in WCDMA Downlink

In order to increase throughput using high order data modulations in wide-band code-division multiple-access (WCDMA) downlink, it is necessary to eliminate multipath interferences. In [1] , a multipath interference canceller (MPIC) was proposed, which enables the use of high order modulations in multipath fading channels. However, only packet channels and pilot channels were considered as transmitted code channels. Code channels dedicated to other users and remaining common code channels coexist in practice, and such unknown code channels degrade the performance of MPIC significantly. In this letter, we propose a multipath interference mitigation scheme that removes all the intracell interferences by orthogonal variable spreading factor (OVSF) code characteristics. Simulation results show that the proposed scheme makes it possible to improve total throughput using high order modulations in WCDMA downlink.