在本論文中，我們模擬了一位元量化預編碼(1-bit precoding)在高階調變下的錯誤率(BER)，證實了一位元量化線性預編碼(linear precoding)只能使用4QAM調變，而ㄧ位元非線性預編碼(non-linear precoding)則勉強可以在16QAM的情況下，讓錯誤率達到〖10〗^(-3)，接著我們改造了一個ㄧ位元非線性預編碼的演算法名為下行投影波束成形(POKEMON)，放寬他的一位元的限制，同時我們也比較了提高至二位元後的性能，以及ㄧ位元但是在基地站(base station)有著兩倍天線數量的性能，實驗結果兩者有著差不多的錯誤率，而在高雜訊比時，我們的二位元版本略勝ㄧ點，不過在運行速度上，我們所提出的提升量化解析度完全勝過提升基地站天線數。

In this thesis, we analyze the bit error rate of 1-bit precoding with high order modulation, proof that 1-bit linear precoder only can realize in 4QAM, and 1-bit non-linear precoding just can achieve 〖10〗^(-3) in high SNR with 16QAM.
A non-linear precoder, POKEMON, is limited for 1-bit. We decide to reform it to multi-bits version, and compare the new 2-bits algorithm with 1-bit POKEMON which has double antenna in base station. The simulation result shows that our new algorithm outperform POKEMON in computation complexity and also has same BER.

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