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IEEE Microwave and Guided Wave Letters
Volume 10 Number 1, January 2000

A Novel 3-dB Coupler for MMIC Using Air-Gap Stacked Microstrip Lines

Page 1.

Abstract:

A simple broadside-coupled line structure for MMIC is proposed which uses air-gap stacked microstrip lines and does not require any dielectric process. The analysis and optimization of the coupled line structure were performed by using an electromagnetic simulator. The fabricated 3-dB coupler shows broad-band characteristics (23-45 GHz) with the coupling loss of 3.33 ± 0.46 dB and the transmission loss of 3.73 ± 0.43 dB.

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