我們提出了一套用於LTE下鏈同步及蜂巢搜尋的流程設計，支援TDD及FDD兩種模式、可調性頻寬、以及多天線系統。CP種類、符元時間、小數部分載波頻率偏移將在時域進行估測，而整數部分載波頻率偏移、區段ID、群組ID、精細時間、以及訊框起始點將在頻域上估測。模擬結果顯示，在訊雜比-7.5 dB時，我們提出的方法只需要30至40個訊框的時間便可達到90%蜂巢ID的偵測率，遠低於LTE所要求的100個訊框時間。

We propose a synchronization and cell search procedure for LTE downlink direction, which supports TDD and FDD modes, scalable bandwidth, and multiple antenna systems. The CP-type, symbol timing, and fractional carrier frequency offset (FCFO) will be estimated in the time domain; while integer carrier frequency offset (ICFO), sector ID, group ID, fine timing, and frame timing estimations will be performed in the frequency domain.Simulation results show that at signal-to-noise ratio -7.5 dB,our proposed synchronization and cell search procedure requires 30 ~ 40 frames to achieve 90% cell ID detection rate, which is less than the LTE requirement,100 frames.