The Study Of Equalizer And Delay Line Circuit Basedon LTCC Technology

LTCC(Low Temperature Co-fired Ceramic) technology is a novel material technology developed by Hughes Aircraft in 1982. This technology is aimed to form both passive and active function-integrated modules by integrated passive element in the substrate and surface mount IC and surface mount active chips as well.Equalizer is utilized together with amplifier to flat the output of traveling-wave tube. In the process of equalizer design, attentions should be paid on these targets, such as equalized accuracy, equalized value, insertion loss and return loss. Multilayer wiring capability of LTCC helps for equalizer miniaturization design. As a key component in phased-array radar, delay component is developed to improve the performance of phased-array radar. The delay line is a device for electrical signal delay for a period of time, while the delay component is the device that combines delay line with switch to achieve specific delay function. The small dispersion and insertion loss, high phase accuracy and flat amplitude frequency characteristic are critical to the superior performance of delay component.This paper focuses on LTCC equalizer and LTCC delay component. Firstly, equalizer theory is illustrated to provide theoretical basis for LTCC equalizer, which is based on composite right-left handed(CRLH) transmission line. This novel CRLH resonator is analyzed by controlling the resonant frequency, bandwidth and the equalized value. The LTCC equalizer is proved to be effective for equalizer miniaturization design for the decrease in size and the increase in the number of adjustable parameters. Two LTCC equalizers work in the frequency of 2 to 6GHz and in the frequency of 6 to 18 GHz are manufactured, and the measured results match well with the simulated results. As for LTCC delay component, passive structures are studied firstly. The study focuses on phase effect of cutting angle, the coupling between two parallel lines and isolation hole in LTCC. Finally, DC control circuit for delay component is designed. Simulation design of the delay section and the straight one based on LTCC technology are finished on the basis of previous study. A 6-path LTCC delay component work in Ka-band is formed by the switch, the delay section and the straight one. The size of LTCC delay component is 68mm×48mm×15mm.The test results meet the demand well, the insertion loss is not more than 35.3d B, the standing-wave ratio is not extra than 1.93, the passband ripple is not more than 2.6d B,while the phase linearity is not more than 17 °.