Novel Evanescent-Mode Cavity Filter With Reconfigurable Rat-Race Coupler, Quadrature Coupler and Multi-Pole Filtering Functions

Abstract

A novel evanescent-mode cavity filter with multiple reconfigurable functions including filtering rat-race coupler, filtering quadrature coupler and multi-pole filtering is proposed in this paper. It simply consists of four substrate integrated waveguide (SIW) evanescent-mode cavity resonators which are arranged in a ring loop. By loading piezoelectric actuators on top of each resonator and inserting varactors between adjacent resonators, the structure can achieve multiple reconfigurable functions among filtering rat-race coupler, filtering quadrature coupler and single-ended multi-pole filters, in addition to continuously frequency, independent bandwidth, and power-division tuning. Measurement shows that the filtering quadrature coupler corves a frequency range of 2.08-3.00 GHz with insertion loss of 2.99 ± 0.31dB, while the filtering rat-race coupler corves a frequency range of 2.31-2.71 GHz with insertion loss of 2.97 ± 0.13dB; The single-ended filter can be switched among two-pole, three-pole, and four-pole with frequency range of 2.38 to 3.01 GHz, 2.47 to 3.08 GHz and 2.53 to 3.00 GHz, respectively. Good agreement is obtained between simulated and measured results. INDEX TERMS Evanescent-mode cavity, quadrature coupler, rat-race coupler, reconfigurable filters. FIGURE 1. Structure of the proposed multifunction filtering coupler. (a) 3D-view. (b) Top view.

Near Field Sensing Applications with Tunable Beam Millimeter Wave Antenna Sensors in an All-in-One Chip Design

“…The common coupler types are Parallel-line coupler, Branch-line coupler [55][56][57][58][59], Ratrace coupler [56,57,[60][61][62], Lange coupler, Directional coupler [63][64][65], Lumped-Element coupler [66], and Hybrid coupler [67,68]. The design can be achieved by various structures such as Coplanar waveguide (CPW), Substrate-integrated waveguide (SIW), Microstrip line, etc.…”

Designs of Branch-Line Couplers by Considering the Parasitic Effects of P-I-N Diodes

“…In wireless communication system, antenna usually requires power splitting devices such as power divider [1] and conventional branch-line coupler (BLC) [1] which can achieve 90° phase difference between two transmission paths and equal power delivery. Reconfigurable components [2]- [31] were popular research topics because each of them provided a different desired responses by using one device. [2], [4]- [6], [9]- [11], [13], [14], [18], [19], [24], and [28]- [31] have used varactors/active inductors to adjust their phases, operating frequencies, or power splitting ratios.…”

“…Reconfigurable components [2]- [31] were popular research topics because each of them provided a different desired responses by using one device. [2], [4]- [6], [9]- [11], [13], [14], [18], [19], [24], and [28]- [31] have used varactors/active inductors to adjust their phases, operating frequencies, or power splitting ratios. [3], [7], [8], [23], [25], and [26] have used p-i-n diodes to provide switching couplers and dividers.…”