Research And Design Of Broadband Ltcc Microwave 3db Directional Coupler

With the development of modern electronic countermeasures system and measuring instrument system, microwave system frequently becomes wider and wider. People put a higher bandwidth and size requirements for directional coupler as the constant pursuit of portability and integration, which is widely used in microwave system. As we all know, multiple broadside-coupled stripline directional couplers and Lange couplers can achieve wide bandwidth and high performance. However, the bandwidth of a single broadside-coupled stripline coupler is only one octave or so. Lange coupler have to use gold or jumper wire press welder welding. The design of this paper is all realized by LTCC(Low Temperature Cofired Ceramic, LTCC) technology. As one technology of increasing RF module integration, LTCC has become the current research focus and emphasisThis paper start from basic theory, achieve the three broad-band microwave LTCC 3dB directional coupler, its significant advantage is excellent performance, small size, high reliability, electrical performance and good consistency, suitable for mass production and low cost. Frequency from low to high were 200MHz-600MHz,1.7GHz-2.0GHz,2GHz-6GHz respectively.200MHz-600Mz,1.7GHz～2.0GHz use broadside-coupled stripline structure. 2GHz-6GHz. coupler structure design combines with LTCC technology, by improving the air bridge Lange, it realizes a broadband coupler and small volume. In this paper, without gold bonding, Lange's electrical performance is in good consistency, thus suitable for batch. Here the two directional couplers 200MHz-600MHz,1.7GHz～2.0GHz were being produced and tested.This study is part of the study of the National Natural Science Foundation of China (Fund number:60671038) "package of digital beamforming based on radio frequency system for basic research".