Preamble generation method to improve timing estimation for OFDM system using training sequence

A novel preamble structure is proposed for a timing estimation for orthogonal frequency division multiplexing (OFDM) systems such as the IEEE 802.11 and the IEEE 802.15.4g/4m. The boundary estimation becomes easy because of the outstanding correlation property between the short training sequence (STS) and the proposed long training sequence (LTS). The proposed method can be applied to OFDM systems which use STS and LTS preamble structures. The proposed LTS scheme considerably improves the performance of timing estimation in comparison with the method of using legacy LTS. This method has been applied to the IEEE 802.15.4m standard.