Micro-strip dual-mode filter with intensified coupling and harmonic suppression characteristics

Abstract

The invention discloses a micro-strip dual-mode filter with intensified coupling and harmonic suppression characteristics, which is a microwave band-pass filter with high performance. A microwave dielectric substrate comprises a square ring resonator (1), an L-shaped coupling structure, a perturbation element (3) and a 50-ohm incoming and outgoing feeder, wherein, the L-shaped coupling structure at the input end (21) and the L-shaped coupling structure at the output end (22) are symmetrically distributed corresponding to a diagonal of the square ring resonator (1); the L-shaped coupling structure at the input end (21) is connected with the 50-ohm incoming feeder (41); the L-shaped coupling structure at the output end (22) is connected with the 50-ohm outgoing feeder (42); the perturbation element (3) is positioned on a corner of the square ring resonator (1) and is connected with the square ring resonator (1). The dual-mode micro-strip band-pass filter is applicable to the design of mobile communication radio frequency (RF) front end, can obtain greater port coupling quantity than traditional micro strip, thereby reducing the insertion loss, and very effectively suppressing the higher harmonic response simultaneously.

Description

technical field [0001] The invention can be applied to the radio frequency front end of the mobile communication system, can greatly improve the harmonic suppression degree of the system and reduce the in-band insertion loss, and is a high-performance microwave bandpass filter. Background technique [0002] The modern mobile communication technology system puts forward higher and higher requirements on the performance of the radio frequency front end, and the filter at the front end of the radio frequency affects the transmission power and signal-to-noise ratio of the system to a large extent. Microstrip dual-mode filters have attracted much attention due to their low cost, easy processing and flexible implementation. Due to its own double-tuning characteristics, the volume is halved compared to filters of the same order. However, the insertion loss of ordinary microstrip dual-mode filters is large, and its inherent second harmonic will deteriorate the spurious suppression ...

AI Technical Summary

Problems solved by technology

However, the first technique will reduce the bandwidth of the filter, while the latter two will introduce additional structures, which will not only increase the circuit scale, but also deteriorate the transmission characteristics in the passband and increase the insertion loss.

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