在同調解調接收機中，因需要一同調載波才能有效的解調出信號，所以必須很確切的知道解調載波的相位是否和發射載波同步，而這樣的電路一般會使用鎖相迴路來實現，軻斯塔迴路就是利用兩個平行的鎖相迴路來解調信號，但在非同調解調接收機中，利用差分編碼和解碼的技巧，將信號載在前後兩個發射信號之間的相位差，如此就可以在未知載波信號相位的情形下，也能成功的解調出信號，並簡化接收機的電路複雜度。
本論文主要分為以下四個部分：第一部份為解調器的解調原理和系統架構。第二部分為本地振盪器的設計，這裡我們使用半集總元件來設計我們的振盪電路。第三部分為降頻混波器的設計，我們在此使用疊加組態來改善本地振盪埠對高頻埠的隔離度。第四部分為系統模擬和實作量測，比較利用類比乘法器解調的相位正交解調器和利用數位乘法器解調的相位正交解調器的錯誤率。此種調變解調的方法也可以應用到更高位元的調變解調上。

In coherent demodulation, a coherent carrier is needed to demodulate signal successfully. Phase-locked loop can be used to realize the phase synchronization. For example, Costas loop uses two parallel phase-locked loop to recover the carrier. On the other hand, in noncoherent demodulation, one may use differential coding and decoding techniques to demodulate signal without knowing exact carrier phase. This will greatly simplify the circuit.

In the thesis, firstly the demodulation theory and circuit topology are given. Then, oscillator circuit design using semi-lump elements is presented. Next, cascode topology are used in mixer design to improve LO-to-RF isolation. Finally, the result of system simulations and experiments are given. The bit error rate of I/Q demodulator using analog multiplier is compared to that using digital multiplier. The modulation and demodulation technique proposed in this research are also suitable for other M-ary signal modulation and demodulation.

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