A novel substrate integrated microstrip to ultra-thin cavity filter transition operating in the W-band is proposed in this letter.The structure is a new method of connecting microstrip circuits and waveguide filters,a...A novel substrate integrated microstrip to ultra-thin cavity filter transition operating in the W-band is proposed in this letter.The structure is a new method of connecting microstrip circuits and waveguide filters,and this new structure enables a planar integrated transition from microstrip lines to ultra-thin cavity filters,thereby reducing the size of the transition structure and achieving miniaturization.The structure includes a conventional tapered microstrip transition structure,which guides the electromagnetic field from the microstrip line to the reduced-height dielectric-filled waveguide,and an air-filled matching cavity which is placed between the dielectric-filled waveguide and the ultra-thin cavity filter.The heights of the microstrip line,the dielectric-filled waveguide and the ultra-thin cavity filter are the same,enabling seamless integration within a planar radio-frequency(RF)circuit.To facilitate testing,mature finline transition structures are integrated at both ends of the microstrip line during fabrications.The simulation results of the fabricated microstrip to ultra-thin cavity filter transition with the finline transition structure,with a passband of 91.5-96.5 GHz,has an insertion loss of less than 1.9 dB and a return loss lower than-20 dB.And the whole structure has also been measured which achieves an insertion loss less than 2.6 dB and a return loss lower than-15 dB within the filter's passband,including the additional insertion loss introduced by the finline transitions.Finally,a W-band compact up-conversion module is designed,and the test results show that after using the proposed structure,the module achieves 95 dBc suppression of the 84 GHz local oscillator.It is also demonstrated that the structure proposed in this letter achieves miniaturization of the system integration without compromising the filter performance.展开更多
目前出现的大规模(large-scale)的多媒体应用对 Internet 提出了新的挑战。传统的 IP 组播(IP multicast,IPM)由于实现技术的复杂性,很难在 Internet 上推广。相反,基于叠加网络(overlay network,ON)的解决方案则受到各方面的关注。本...目前出现的大规模(large-scale)的多媒体应用对 Internet 提出了新的挑战。传统的 IP 组播(IP multicast,IPM)由于实现技术的复杂性,很难在 Internet 上推广。相反,基于叠加网络(overlay network,ON)的解决方案则受到各方面的关注。本文针对大规模实时多媒体应用需求,通过建立评价参数模型对 ON 协议进行研究。尤其对 overlay组播(overiay multicast,OM)的 QoS 控制、可靠性以及可伸缩性机制进行了分析。与 IPM 相比,OM 虽然有性能代价(performance penalty)问题,但是 OM 能方便、灵活地利用多种高层的功能实现,基于 hop-by-hop 方式有效地提供E2E(end-to-end)的可靠性和 Qos 保障,并且较好地支持 TCP-friendliness,具有良好的可伸缩性。此外,OM 的基础网络(infrastructure/underlay network)无关性,也使其容易在 Internet 中进行配置。以上特性使得 OM 成为支持 Inter-net 上大规模实时多媒体应用的最具前景的技术。展开更多
基金Supported by the Fundamental Research Funds for the Central Universities(ZYGX2021J008)。
文摘A novel substrate integrated microstrip to ultra-thin cavity filter transition operating in the W-band is proposed in this letter.The structure is a new method of connecting microstrip circuits and waveguide filters,and this new structure enables a planar integrated transition from microstrip lines to ultra-thin cavity filters,thereby reducing the size of the transition structure and achieving miniaturization.The structure includes a conventional tapered microstrip transition structure,which guides the electromagnetic field from the microstrip line to the reduced-height dielectric-filled waveguide,and an air-filled matching cavity which is placed between the dielectric-filled waveguide and the ultra-thin cavity filter.The heights of the microstrip line,the dielectric-filled waveguide and the ultra-thin cavity filter are the same,enabling seamless integration within a planar radio-frequency(RF)circuit.To facilitate testing,mature finline transition structures are integrated at both ends of the microstrip line during fabrications.The simulation results of the fabricated microstrip to ultra-thin cavity filter transition with the finline transition structure,with a passband of 91.5-96.5 GHz,has an insertion loss of less than 1.9 dB and a return loss lower than-20 dB.And the whole structure has also been measured which achieves an insertion loss less than 2.6 dB and a return loss lower than-15 dB within the filter's passband,including the additional insertion loss introduced by the finline transitions.Finally,a W-band compact up-conversion module is designed,and the test results show that after using the proposed structure,the module achieves 95 dBc suppression of the 84 GHz local oscillator.It is also demonstrated that the structure proposed in this letter achieves miniaturization of the system integration without compromising the filter performance.
文摘目前出现的大规模(large-scale)的多媒体应用对 Internet 提出了新的挑战。传统的 IP 组播(IP multicast,IPM)由于实现技术的复杂性,很难在 Internet 上推广。相反,基于叠加网络(overlay network,ON)的解决方案则受到各方面的关注。本文针对大规模实时多媒体应用需求,通过建立评价参数模型对 ON 协议进行研究。尤其对 overlay组播(overiay multicast,OM)的 QoS 控制、可靠性以及可伸缩性机制进行了分析。与 IPM 相比,OM 虽然有性能代价(performance penalty)问题,但是 OM 能方便、灵活地利用多种高层的功能实现,基于 hop-by-hop 方式有效地提供E2E(end-to-end)的可靠性和 Qos 保障,并且较好地支持 TCP-friendliness,具有良好的可伸缩性。此外,OM 的基础网络(infrastructure/underlay network)无关性,也使其容易在 Internet 中进行配置。以上特性使得 OM 成为支持 Inter-net 上大规模实时多媒体应用的最具前景的技术。
