A dual-band bandpass filter chip based on ltcc

Abstract

The invention discloses an LTCC-based dual-frequency band-pass filter chip, which belongs to the field of microwave transmission; the chip has a left-right symmetrical structure, and the middle is a first parallel circuit composed of an inductor and a capacitor; each of the two ends is connected in series with an inductor L1 Connect the input and output ports with the capacitor C1; at the same time, the two ends of the inductor L1 are connected in parallel with the second parallel circuit and the third parallel circuit grounded. The three parallel circuits form a filter structure, and the two capacitors C1 form an impedance matching structure; by controlling the capacitance inductance , when the signals of each frequency band are input, the signal at the low frequency is preliminarily filtered out by the capacitor C1; due to the transmission zero point introduced by the second and third parallel circuits, when the signal passes through, the low frequency signal and the high frequency signal above 5.31GHz will be separated will be filtered out; due to the transmission zero introduced by the first parallel circuit, when the signal passes through, the signal between the two passbands will be filtered out; finally, only the signal in the two passbands will be output, thus realizing dual-band bandpass filtering. The invention ensures low insertion loss in the passband.

Description

technical field [0001] The invention belongs to the field of microwave transmission and the field of integrated circuits, and relates to a passive dual-frequency filter chip, in particular to a dual-frequency bandpass filter chip based on LTCC. Background technique [0002] In recent years, with the rapid development of mobile communication systems, 5G technology has emerged and has been widely used within a certain range. As a new generation communication system, 5G has technical advantages such as short delay time, high data rate, low energy consumption and large data flow. In order to meet the development needs of the 5G era, radio frequency components are also facing more stringent challenges. [0003] As the device with the largest proportion of the RF front-end, the filter is an indispensable part of mobile communication equipment. Its function is mainly to perform signal processing, retain specific frequency components and filter out useless frequency components, so...

AI Technical Summary

Problems solved by technology

[0005] However, there is currently a lack of miniaturized and low-loss dual-band bandpass filters on the market

Like traditional PCB technology, it is impossible to realize multi-layer wiring and internal embedded passive devices, and it is also impossible to use ceramic materials with excellent characteristics in high frequency and microwave, resulting in the disadvantages of large device size and high loss

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