High performance five-order band-pass filter based on LTCC technology research

A high performance five-order band-pass filter based on LTCC technology was designed. The five-order band-pass filter is composed of five high-performance resonator, among which transmission zeros achieved good stopband attenuation through cross coupling. Software ADS and HFSS were used to optimize the simulation. Good agreements were found between the test and simulation results. The centre frequency of the five-order band-pass filter is 2.06 GHz and the bandwidth is 560 MHz. Insertion loss is less than 3.6 dB within the scope of pass-band, in the frequency ranges of 0-1.279 GHz, the out-of-band attenuation is higher than 45 dB. Moreover, the size is 6.2 mm × 2.1 mm × 1mm. The filter range belongs to LS spectrum. So, the strip-line distributed structure was able to realize the miniaturization of the filter.