An L-band HTS duplexer with improved performance for communication applications has been developed.This is an improved version of the duplexer previously developed by our group.The duplexer was composed of a T-junctio...An L-band HTS duplexer with improved performance for communication applications has been developed.This is an improved version of the duplexer previously developed by our group.The duplexer was composed of a T-junction and two channels.Each channel has a 10-pole quasi-elliptic function bandpass HTS filter with a bandwidth of 27 MHz,and center frequencies at 1200 MHz and 1260 MHz.To achieve higher performance,especially a good balance between selectivity and flat group delay,the two pairs of transmission zeros from the two filters were reassigned so that one pair is used for high selectivity and the other for flat group delay.To reduce the influence of parasitical coupling,new coupling structures were developed in the simulation process.The duplexer was fabricated on a 2 inch diameter,0.5 mm thick LaAlO3 wafer with a double-sided YBCO film.The measured results showed a very high performance:a mid-band insertion loss of 0.2 dB,a return loss better than-14 dB,a shape factor better than 1.4:1,an out-of-band rejection of better than 70 dB in a wide frequency range up to 3 GHz and excellent isolation(higher than 80 dB) between the two channels.In addition,the frequency band 5 ns group delay variation is over 10.5 MHz(38.7% of 1 dB bandwidth).展开更多
Relations between helicity coupling amplitude and L-S coupling amplitude are discussed. The equivalence condition for these two kinematic analysis methods and the limitations of the L-S coupling amplitude are also stu...Relations between helicity coupling amplitude and L-S coupling amplitude are discussed. The equivalence condition for these two kinematic analysis methods and the limitations of the L-S coupling amplitude are also studied in this paper.展开更多
基金supported by the External Cooperation Program of the Chinese Academy of Sciences (GJHZ1007)Knowledge Innovation Program of the Chinese Academy of Sciences (KJCX2-YW-W16)
文摘An L-band HTS duplexer with improved performance for communication applications has been developed.This is an improved version of the duplexer previously developed by our group.The duplexer was composed of a T-junction and two channels.Each channel has a 10-pole quasi-elliptic function bandpass HTS filter with a bandwidth of 27 MHz,and center frequencies at 1200 MHz and 1260 MHz.To achieve higher performance,especially a good balance between selectivity and flat group delay,the two pairs of transmission zeros from the two filters were reassigned so that one pair is used for high selectivity and the other for flat group delay.To reduce the influence of parasitical coupling,new coupling structures were developed in the simulation process.The duplexer was fabricated on a 2 inch diameter,0.5 mm thick LaAlO3 wafer with a double-sided YBCO film.The measured results showed a very high performance:a mid-band insertion loss of 0.2 dB,a return loss better than-14 dB,a shape factor better than 1.4:1,an out-of-band rejection of better than 70 dB in a wide frequency range up to 3 GHz and excellent isolation(higher than 80 dB) between the two channels.In addition,the frequency band 5 ns group delay variation is over 10.5 MHz(38.7% of 1 dB bandwidth).
基金国家自然科学基金，DURF of SEC，国家重点实验室基金，CTNP of LHIA National Lab of China，中国博士后科学基金
文摘Relations between helicity coupling amplitude and L-S coupling amplitude are discussed. The equivalence condition for these two kinematic analysis methods and the limitations of the L-S coupling amplitude are also studied in this paper.
