In this paper, we present the complex permittivity measurement of low-loss substrates based on a microstrip-line-excited split-ring resonator (SRR). Permittivity of an unknown substrate is calculated based on the chan...In this paper, we present the complex permittivity measurement of low-loss substrates based on a microstrip-line-excited split-ring resonator (SRR). Permittivity of an unknown substrate is calculated based on the change in oscillation frequency of SRR caused by the material-under-test (MUT) above the SRR. Theoretical analysis and results of the simulations and experiments demonstrate the microstrip-line-excited SRR can be used to effectively improve measurement sensitivity. Simple equations for measurement of low-loss substrates using SRR are proposed and experimentally verified.展开更多
In this paper, an antenna with reconfigurable band notches, for cognitive radio applications, is proposed. The antenna can be operated as ultra wideband, and is reconfigurable in terms of the ability to select a notch...In this paper, an antenna with reconfigurable band notches, for cognitive radio applications, is proposed. The antenna can be operated as ultra wideband, and is reconfigurable in terms of the ability to select a notched band in the SRR resonant frequency. The reconfigurable band notches are induced using a band-stop filter based on split-ring resonators (SRRs), and are controlled using electronic switches mounted over the SRRs. For this sake, the design of the band-stop filter is proposed. A prototype of filter is fabricated and measured. The incorporation of a band-stop filter, into a wideband antenna, is then looked into. The proposed antenna is designed and simulated using Ansoft HFSS. A prototype of the antenna is fabricated and measured. A good analogy between simulated and measured results is obtained.展开更多
文摘In this paper, we present the complex permittivity measurement of low-loss substrates based on a microstrip-line-excited split-ring resonator (SRR). Permittivity of an unknown substrate is calculated based on the change in oscillation frequency of SRR caused by the material-under-test (MUT) above the SRR. Theoretical analysis and results of the simulations and experiments demonstrate the microstrip-line-excited SRR can be used to effectively improve measurement sensitivity. Simple equations for measurement of low-loss substrates using SRR are proposed and experimentally verified.
文摘In this paper, an antenna with reconfigurable band notches, for cognitive radio applications, is proposed. The antenna can be operated as ultra wideband, and is reconfigurable in terms of the ability to select a notched band in the SRR resonant frequency. The reconfigurable band notches are induced using a band-stop filter based on split-ring resonators (SRRs), and are controlled using electronic switches mounted over the SRRs. For this sake, the design of the band-stop filter is proposed. A prototype of filter is fabricated and measured. The incorporation of a band-stop filter, into a wideband antenna, is then looked into. The proposed antenna is designed and simulated using Ansoft HFSS. A prototype of the antenna is fabricated and measured. A good analogy between simulated and measured results is obtained.
