The transmission properties of double-ring split ring resonator(SRR) arrays and closed ring resonator arrays are measured using terahertz(THz) time-domain spectroscopy. This technique allows for the simultaneous measu...The transmission properties of double-ring split ring resonator(SRR) arrays and closed ring resonator arrays are measured using terahertz(THz) time-domain spectroscopy. This technique allows for the simultaneous measurement of the amplitude and phase of the transmission coefficient as a function of frequency. The ability to directly measure the phase spectrum is expected to be important in characterizing potential negative index media. In the employed experimental geometry, THz pulses are normally incident on the arrays. Thus, the magnetic field lies in the plane of the arrays and cannot contribute to the magnetic resonance of the SRR. However, it is found that the electric field, when appropriately polarized, can couple to the magnetic resonance. Shifts in the resonance properties with changes in the SRR dimensions and the substrate medium are measured, the results of which are consistent with theory.展开更多
In this paper, high directive antenna using metamaterial property is presented for wireless medical systems. The antenna is constructed by semi-circular patch and hexagonal closed ring resonator (HCRR). For medical ap...In this paper, high directive antenna using metamaterial property is presented for wireless medical systems. The antenna is constructed by semi-circular patch and hexagonal closed ring resonator (HCRR). For medical applications such as wireless patient movement monitoring, telemetry and telemedicine, communication devices working at ISM band frequency is needed. Here, the requirement is completed with improved directivity such as 16 dBi. And also impedance matching also achieved with low reflection loss -20 dB. This antenna works for multiple frequency bands (Industrial, Scientific and Medical-ISM 2.45 GHz, WLAN 5.3 GHz and GSM 1.9 GHz) with improved directivity.展开更多
文摘The transmission properties of double-ring split ring resonator(SRR) arrays and closed ring resonator arrays are measured using terahertz(THz) time-domain spectroscopy. This technique allows for the simultaneous measurement of the amplitude and phase of the transmission coefficient as a function of frequency. The ability to directly measure the phase spectrum is expected to be important in characterizing potential negative index media. In the employed experimental geometry, THz pulses are normally incident on the arrays. Thus, the magnetic field lies in the plane of the arrays and cannot contribute to the magnetic resonance of the SRR. However, it is found that the electric field, when appropriately polarized, can couple to the magnetic resonance. Shifts in the resonance properties with changes in the SRR dimensions and the substrate medium are measured, the results of which are consistent with theory.
文摘In this paper, high directive antenna using metamaterial property is presented for wireless medical systems. The antenna is constructed by semi-circular patch and hexagonal closed ring resonator (HCRR). For medical applications such as wireless patient movement monitoring, telemetry and telemedicine, communication devices working at ISM band frequency is needed. Here, the requirement is completed with improved directivity such as 16 dBi. And also impedance matching also achieved with low reflection loss -20 dB. This antenna works for multiple frequency bands (Industrial, Scientific and Medical-ISM 2.45 GHz, WLAN 5.3 GHz and GSM 1.9 GHz) with improved directivity.
