Pre-Rake System Applied with Frequency Domain Equalization In Multi-Code TDD-CDMA
Jun Hwan Lee, Masaki Nakagawa · 2006
In this paper we propose a Pre-rake system with a frequency domain equalizer at multi-code transmission. The Pre-rake system has been well known technology in TDD-CDMA to make a mobile station (MS) simple. However, it still has a residual path diversity loss. To gather all the residual paths requires an additional hardware such as a rake combiner to MS. For the reason Pre/Post-rake system has already been proposed, and it could increase the performance gain comparing with a Pre-rake only system by obtaining more path diversity. In the mean time, it has been verified that the maximal ratio post-rake combiner (MRC) at time domain can be designed with a less hardware complexity with a frequency domain MRC (MRC-FDE) and its performance is almost the same without considering the power loss due to the insertion of a cyclic prefix (CP). The paper introduces Pre-rake/FDE and shows the system design and presents with the numerical performance results.