此論文主要研究對於分波多工濾波器(Wavelength Division Multiplexing filters)，主要目的為連接不同階數的馬赫-曾德爾干涉多路復用濾波器(cascaded Mach-Zehnder Interferometer multiplexer)，利用一分二的分散方法連接來達到低損耗且有平坦通帶的波長通道分段輸出。
利用不同原理設計的級聯馬赫-曾德爾干涉多路復用濾波器，可以達到需要分開波段的效果。其中需要將各個階(stage)得到的耦合係數與相位延遲組合，控制兩端輸出能具有半個自由光譜範圍(Free Spectral Range) 的波形，讓輸出的兩端能夠得到相鄰的通帶，即得到不同設計的寬通帶與寬阻帶分波器。
其中在各階(stage)濾波器裡所使用定向耦合器會因為耦合係數受波長影響較大，不在中心波段的部分會有比較多的串音干擾(crosstalk)。論文中主要是以基於STA反向工程法(inverse-engineering)的反向工程任意分光耦合器(Arbitrary ratio power splitters coupler)來取代具有不同分光率的定向耦合器(Directional coupler)，其中是利用反向工程任意分光耦合器對於波長變化穩定性高的特性來減少對級聯濾波器波形的輸出干擾，因此使用反向工程任意分光耦合器的波長分段多路復用濾波器可以讓分光效果更好。最後比較將反向工程任意分光耦合器替換成定向耦合器的前後差異。

This paper mainly studies Wavelength Division Multiplexing filters, the main purpose of which is to connect cascaded Mach-Zehnder interferometer multiplexers of different orders, and use the one-to-two dispersion method to achieve low-loss and flat passband wavelength channel segment output. In this case, the STA-based inverse-engineering arbitrary ratio power splitters are used to replace the directional coupler with different split ratios. Features to reduce the output interference to the cascade filter waveform, so the wavelength segmentation multiplexing filter with inverse-engineering arbitrary ratio power splitters can make the splitting effect better. Finally, we compare the differences before and after the replacement of directional couplers with inverse-engineering arbitrary ratio power splitters.

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