A novel balanced BPF using the half-mode substrate integrated waveguide has a central frequency of 5.22 GHz with 0.91 GHz BW and the in-band insertion loss of 2.1 dB. The size of an HMSIW is about half of the substrate integrated waveguide (SIW). The common-mode rejection levels are greater than 40 dB with in-band insertion losses around 2 dB.

1.本專利案以微帶線透過槽孔耦合方式將能量傳至基板合成之半模波導結構，並以此結構為基礎，設計一款具共模壓制效果之平衡式帶通濾波電路，中心頻率為5.22 GHz，頻寬0.91 GHz，損耗2.1 dB。
2.微帶線槽孔耦合基板合成之半模波導結構，此為同類型結構之濾波器首創，電路的Q值遠大一般常用之平面傳輸線電路（如微帶線），而電路之共模壓制效果超過40 dB，效果優於其他結構之平衡式帶通濾波電路。
3.濾波器結構能移轉至其他頻段與不同頻寬要求的濾波器設計上，具有普遍性與便利性。
4.本專利案的構想尚未見諸其他人所發表之文獻上，目前中華民國專利公報內，也還找不類似結構之帶通濾波器濾的資料。
5.需要無線通訊或是無線傳送與接收的場合越來越多，未來市場可期。

The substrate integrated waveguide balanced BPF has great EMC immunity property. It also has the advantages of wide BW, wide stopband, dual bands, and good signal selectivity.  It can be used as a RF front-end filter component of a wireless communication system, such as wifi and WLAN systems, and cellar phone base station.