Performance Analysis of In-band and Band-edge Channel Estimations for OFDM System

• Main Authors: Jia-Hong Lai, 賴嘉鴻
• Other Authors: Chi-Min Li
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/55379780672120090302

碩士 === 國立臺灣海洋大學 === 通訊與導航工程學系 === 100 === Orthogonal Frequency Division Multiplexing (OFDM) system has been widely used in many wireless communication systems, such as Long Term Evolution (LTE), Worldwide interoperability for Microwave Access (WiMAX) and 802.11n. To reduce the signal fading caused by the multipath, channel estimation is a very important issue for a wireless communication. In a practical OFDM system, Virtual Subcarriers (VSs), which carry no power are inserted to reduce the adjacent channel interferences and ease the implementation of filter. Nevertheless, channel frequency responses in these VSs are not available, which will degrade the channel estimation. In this thesis, frequency response of the channel is divided into two parts, i.e., in-band and band-edge. Several conventional methods for the channel estimation are provided and compared. Besides, a BER performance prediction method of the linear interpolation is provided in this thesis. For the band-edge response, the AR model and Regularized Least Square (RLS) estimations are proposed to improve the performance degradation for the adoption of VSs.