Design of a miniaturized 3 dB lumped element coupler using LTCC technology

Low temperature cofired ceramic (LTCC) is an effective method to realize the miniaturization, high reliability and low cost for microwave and high-frequency devices. In the paper, a miniaturized 3 dB LTCC coupler using lumped elements is proposed based on the even-odd decomposition method for the built of image-reject mixer (IRM) in receiver systems. With a novel and compact structure, the coupler has a working frequency of 50-70 MHz while the size is only 14.6mm×8.3mm×1mm. EM simulation results show that the coupler has a good performance when using space effectively, which can be widely applied into high integrated RF module in radar and communication systems.