DUPLEXERS AND RELATED DEVICES FOR 5G/6G AND SUBSEQUENT PROTOCOLS AND FOR MM-WAVE AND TERAHERTZ APPLICATIONS

A stub resonator based T-shaped duplexer for use in communication systems is proposed. The T-shaped duplexer comprises a T-shaped microstrip duplexer body having a first rectangular-shaped body section and a second rectangular-shaped body section that extends from the first-rectangular shaped section in a perpendicular position relative to the first rectangular-shaped section. Three connection ports include a first connection port disposed at an open end of the second rectangular-shaped body section, a second connection port disposed at one end of the first rectangular-shaped body section, and a third connection port disposed at another end of the first rectangular-shaped body section. Two bandpass filters are connected to the first rectangular-shaped body section of the T-shaped microstrip duplexer body, each bandpass filter comprising a rectangular microstrip structure, a first rectangular stub resonator structure extending from the rectangular microstrip structure in a perpendicular direction relative to the microstrip structure, and a second rectangular stub resonator structure extending from the rectangular microstrip structure in a perpendicular direction relative to the microstrip structure and being in a parallel position relative to the first rectangular stub resonator structure and being separated from the first rectangular stub resonator structure by a gap distance. Each of the two bandpass filters creates an Electromagnetically Induced Transparency (EIT) window within a frequency absorption region of the bandpass filter to allow a signal to pass at a pre-tuned frequency band.