Design of Triple-Mode Ring Resonator for Wideband Microstrip Bandpass Filters

摘要: A triple-mode microstrip ring resonator core for the design of bandpass filters is proposed in this paper. It a modification conventional single-mode with pair open-ended coupled lines and shunt open stub transmission-line path substituted to form resonator. Since possesses three resonances, one at center frequency other two near edges passband, flat passband response can be achieved when it employed implement filter. The also exhibits attenuation poles close thereby offering sharp rejection filter response. Moreover, since signal applied input port effectively forced travel mainly through transmission line over frequency, loss incurred by minimized. Extensive theoretical analysis example prototypes based on structure are given. prototype filters's performance validated both simulations experiments, where good agreement prediction observed.