In this paper a metamaterial-inspired antenna with high gain and good directivity is designed. Based on the concept of composite right/left-handed transmission line (CRLH-TL), the proposed antenna is realized based on...In this paper a metamaterial-inspired antenna with high gain and good directivity is designed. Based on the concept of composite right/left-handed transmission line (CRLH-TL), the proposed antenna is realized based on three leakage wave unit cell and a left handed circular ring slot incorporated on the surface. The maximum achievable gain at the resonant frequency of 5.6GHz is 6.933 dBi, and the return loss at 5.6 GHz can be –20 db. This proposed design has a simple structure and a compact dimension of 35 mm*40 mm*1 mm, which is suitable for particular wireless communication application such as WiFi and WLAN.展开更多
The refraction index of the quantized lossy composite right-left handed transmission line（CRLH-TL） is deduced in the thermal coherence state. The results show that the negative refraction index（herein the left-hand...The refraction index of the quantized lossy composite right-left handed transmission line（CRLH-TL） is deduced in the thermal coherence state. The results show that the negative refraction index（herein the left-handedness） can be implemented by the electric circuit dissipative factors（i.e., the resistances R and conductances G） in a higher frequency band（1.446 GHz≤ ω ≤ 15 GHz）, and flexibly adjusted by the left-handed circuit components（Cl, Ll） and the right-handed circuit components（Cr, Lr） at a lower frequency（ω = 0.995 GHz）. The flexible adjustment for left-handedness in a wider bandwidth will be significant for the microscale circuit design of the CRLH-TL and may make the theoretical preparation for its compact applications.展开更多
In this paper, a new miniaturized wide-pass-band filter at U band based on composite right/left- handed transmission line (CRLH TL) is implemented. The CRLH TL contributed to a broadband filter is a balanced structure...In this paper, a new miniaturized wide-pass-band filter at U band based on composite right/left- handed transmission line (CRLH TL) is implemented. The CRLH TL contributed to a broadband filter is a balanced structure with a small size of only 1.428 mm*0.5530 mm. The frequency characteristics are simulated and the results show that the 3 dB band width of the proposed filter is about 13.5 GHz from 45.8 GHz to 59.3 GHz. The insertion loss is quite flat through the pass-band and the return loss is relatively low.展开更多
In this paper,novel dual-band (DB) branch-line couplers (BLCs) employing a composite right/left handed transmission line (CRLH TL) and fractal geometry are presented for the first time.The CRLH TL,with specified chara...In this paper,novel dual-band (DB) branch-line couplers (BLCs) employing a composite right/left handed transmission line (CRLH TL) and fractal geometry are presented for the first time.The CRLH TL,with specified characteristic impedance and phase shift,consists of lumped elements for the left handed (LH) part and fractal-shaped microstrip lines (MLs) for the right handed (RH) part,which can be designed separately.Two designed BLCs are involved in size reduction,one using a 3/2 fractal curve of first iteration,the other constructed based on a hybrid shape of fractal and meandered lines.A miniaturized principle for CRLH TL realization is derived and an exact design method for fractal implementation is developed.For verification,an example coupler was fabricated and measured.Consistent numerical and experimental results confirmed the design concept,showing that the BLCs obtain DB behavior centered at 0.9 GHz and 1.8 GHz respectively with good in-band performance,except for slightly larger coupled insertion loss for the hybrid-shaped BLC case.In addition,the proposed fractal-and hybrid-shaped BLCs obtained a 49.7% and 64.1% size reduction respectively relative to their conventional counterparts working in the lower band.The most important contributions of this article are the demonstration of compatibility between the fractal and CRLH TL techniques and the provision of an alternative approach and a new concept for designing devices.展开更多
A wideband composite right/left handed transmission line (CRLH TL) in conjunction with its corresponding equivalent circuit model is studied based on a cascaded complementary single split ring resonator (CCSSRR).The c...A wideband composite right/left handed transmission line (CRLH TL) in conjunction with its corresponding equivalent circuit model is studied based on a cascaded complementary single split ring resonator (CCSSRR).The characterization is performed by theory analysis,circuit simulation,and full-wave electromagnetic (EM) simulation.The negative refractive index (NRI) and backward wave propagation performance of the CRLH TL are demonstrated.For application,a bandpass filter (BPF) with enhanced out-of-band selectivity and harmonic suppression operating at the wireless local area network (WLAN) band is designed,fabricated,and measured by combining the CRLH TL with a complementary electric inductive-capacitive resonator (CELC).Three CELC cells with wideband stopband performance in the conductor strip and ground plane,respectively,are utilized in terms of single negative permeability.The design concept has been verified by the measurement data.展开更多
文摘In this paper a metamaterial-inspired antenna with high gain and good directivity is designed. Based on the concept of composite right/left-handed transmission line (CRLH-TL), the proposed antenna is realized based on three leakage wave unit cell and a left handed circular ring slot incorporated on the surface. The maximum achievable gain at the resonant frequency of 5.6GHz is 6.933 dBi, and the return loss at 5.6 GHz can be –20 db. This proposed design has a simple structure and a compact dimension of 35 mm*40 mm*1 mm, which is suitable for particular wireless communication application such as WiFi and WLAN.
基金supported by the National Natural Science Foundation of China(Grant Nos.61205205 and 6156508508)the General Program of Yunnan Provincial Applied Basic Research Project,China(Grant No.2016FB009)the Foundation for Personnel Training Projects of Yunnan Province,China(Grant No.KKSY201207068)
文摘The refraction index of the quantized lossy composite right-left handed transmission line（CRLH-TL） is deduced in the thermal coherence state. The results show that the negative refraction index（herein the left-handedness） can be implemented by the electric circuit dissipative factors（i.e., the resistances R and conductances G） in a higher frequency band（1.446 GHz≤ ω ≤ 15 GHz）, and flexibly adjusted by the left-handed circuit components（Cl, Ll） and the right-handed circuit components（Cr, Lr） at a lower frequency（ω = 0.995 GHz）. The flexible adjustment for left-handedness in a wider bandwidth will be significant for the microscale circuit design of the CRLH-TL and may make the theoretical preparation for its compact applications.
文摘In this paper, a new miniaturized wide-pass-band filter at U band based on composite right/left- handed transmission line (CRLH TL) is implemented. The CRLH TL contributed to a broadband filter is a balanced structure with a small size of only 1.428 mm*0.5530 mm. The frequency characteristics are simulated and the results show that the 3 dB band width of the proposed filter is about 13.5 GHz from 45.8 GHz to 59.3 GHz. The insertion loss is quite flat through the pass-band and the return loss is relatively low.
基金supported by the National Natural Science Foundation of China(Nos.60871027and 60971118)the National Basic Research Program(973) of China(No.2009CB613306)
文摘In this paper,novel dual-band (DB) branch-line couplers (BLCs) employing a composite right/left handed transmission line (CRLH TL) and fractal geometry are presented for the first time.The CRLH TL,with specified characteristic impedance and phase shift,consists of lumped elements for the left handed (LH) part and fractal-shaped microstrip lines (MLs) for the right handed (RH) part,which can be designed separately.Two designed BLCs are involved in size reduction,one using a 3/2 fractal curve of first iteration,the other constructed based on a hybrid shape of fractal and meandered lines.A miniaturized principle for CRLH TL realization is derived and an exact design method for fractal implementation is developed.For verification,an example coupler was fabricated and measured.Consistent numerical and experimental results confirmed the design concept,showing that the BLCs obtain DB behavior centered at 0.9 GHz and 1.8 GHz respectively with good in-band performance,except for slightly larger coupled insertion loss for the hybrid-shaped BLC case.In addition,the proposed fractal-and hybrid-shaped BLCs obtained a 49.7% and 64.1% size reduction respectively relative to their conventional counterparts working in the lower band.The most important contributions of this article are the demonstration of compatibility between the fractal and CRLH TL techniques and the provision of an alternative approach and a new concept for designing devices.
基金Project (Nos.60871027 and 60971118) supported by the National Natural Science Foundation of China
文摘A wideband composite right/left handed transmission line (CRLH TL) in conjunction with its corresponding equivalent circuit model is studied based on a cascaded complementary single split ring resonator (CCSSRR).The characterization is performed by theory analysis,circuit simulation,and full-wave electromagnetic (EM) simulation.The negative refractive index (NRI) and backward wave propagation performance of the CRLH TL are demonstrated.For application,a bandpass filter (BPF) with enhanced out-of-band selectivity and harmonic suppression operating at the wireless local area network (WLAN) band is designed,fabricated,and measured by combining the CRLH TL with a complementary electric inductive-capacitive resonator (CELC).Three CELC cells with wideband stopband performance in the conductor strip and ground plane,respectively,are utilized in terms of single negative permeability.The design concept has been verified by the measurement data.
