除此之外，本論文提出了一個新的使用M-PSK訊號之解碼轉發架構，我們利用中繼節點在前兩個時間收到的訊號去估計參考訊號，再將估計的參考訊號用於目前訊號的判斷。由模擬結果顯示，我們提出的新架構有最好的錯誤效能。;Wireless communications is required to transmit quantity of data more and more. The important studying topic is how to transmit the same quantity of data in a shorter period of time. Recently, two-way wireless communication is a popular type of communication technology, where two terminal nodes transmit simultaneously to each other with the help of the relay node. The physical layer network coding can further improve bandwidth efficiency. On the other hand, differential encoding is not required to transmit pilot symbols for channel estimation, so it does not cause rate loss. It is also a communication technology worth studying.
In this thesis, we study differential encoding for two-phase two-way wireless transmission with the single-relay for amplify-and-forward (AF) and decode-and-forward (DF). First, we compare existent techniques under the same conditions. We use M-PSK (phase-shift keying) modulation, and do computer simulations under different channel models. We also study three-phase two-way wireless transmission, and compared two-phase transmission with three-phase transmission based on the same transmission rate.
Besides, in this thesis, we propose a new decode-and-forward scheme using M-PSK signals. This scheme uses the received signals at the relay in previous two time slots to estimate the reference signal, and then decide the current signal according to the estimated reference signal. Simulation results show that the proposed scheme has the best error performance.
