Miniaturized Microstrip Dual-Band Filters Using Dual-Mode Resonators With Flexible Frequency Ratio and Multiple Transmission Zeros

With the rapid development of modern wireless communication systems, the spectrum resource below 6 GHz is becoming increasingly crowded, prompting the exploration of higher frequency solutions, such as the Ku band. However, the demand for lower frequencies remains as is evidenced by technologies like wireless local area networks and the public safety band.