In this paper, a wideband microstrip antenna loaded with split ring resonators (SRRs) has been designed. The proposed antenna consists of three parts: the square patch, the ground and the suspended substrate loaded wi...
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In this paper, a wideband microstrip antenna loaded with split ring resonators (SRRs) has been designed. The proposed antenna consists of three parts: the square patch, the ground and the suspended substrate loaded with SRRs. The bandwidth of the antenna is enlarged by capacitively coupled feed and its resonant frequency can be lowered due to the influence of the loaded SRRs. Simulation results show that the antenna has a 700-MHz bandwidth from 1.70 GHz to 2.40 GHz and the gain is higher than 5.5 dB within the bandwidth. By loading arrays of SRRs, a size reduction of 5.7% is achieved with good radiation features.
Heart rate (HR) signal analysis is widely used in the medicine and medical research area. Physical activities (PA) are commonly recognized to greatly affect the changes of heart rate. A method of Evolutionary Neural N...
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Carrier frequency offset (CFO) between transmitter and receiver carrier generators degrade the performance of adaptive filters seriously, even for very small CFO. Tracking analysis of the affine projection filter is c...
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Carrier frequency offset (CFO) between transmitter and receiver carrier generators degrade the performance of adaptive filters seriously, even for very small CFO. Tracking analysis of the affine projection filter is carried out in the presence of CFO. The energy conservation relation of the affine projection filter with both random and cyclic nonstationarities is derived. Based on the energy conservation relation the steadystate mean-square error is derived in the presence of cyclic nonstationarities. The theoretical results are very close to the Monte Carlo simulation curves. Besides, the simulations results show that the tracking performance improves according to the increase of the order of the affine projection filters.
This paper presents the design and analysis of a bandwidth extended and compact antenna based on CRLH TL (Composite Right/Left Handed Transmission line) with slot loaded. The CRLH TL is realized by the periodic placed...
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This paper presents the design and analysis of a bandwidth extended and compact antenna based on CRLH TL (Composite Right/Left Handed Transmission line) with slot loaded. The CRLH TL is realized by the periodic placed EBG (Electromagnetic Band Gap) unit, the patch and the probe can be regarded as the series capacitance and shunt inductance respectively. Then the microstrip antenna is supposed to resonant in some certain conditions. Combine the left handed resonance frequency with the extra resonance mode, which is stimulated by the loaded of the slots, the bandwidth of the antenna can be extended efficiently. The full-analysis of the antenna is simulated. And the results show that the relative operation frequency bandwidth of the proposed antenna is 9.3% and the overall size of the antenna is only a quarter of wavelength. Besides, the radiation pattern of the antenna in the entire impedance matching band keeps unchanged, which means the radiation bandwidth is in step with the impedance bandwidth.
In this paper, a high-gain and broadband microstrip patch antenna by using 2D metamaterial unit and directors for GSM, WCDMA and WiMAX operations is presented. The proposed antenna has conceptual configuration of the ...
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In this paper, a high-gain and broadband microstrip patch antenna by using 2D metamaterial unit and directors for GSM, WCDMA and WiMAX operations is presented. The proposed antenna has conceptual configuration of the Yagi antenna array, which is realized by the complementary metamaterial units etched on the patch. Furthermore, some directors are applied to enhance the gain of the antenna. The simulation results show that the operation frequency is from 1.57 GHz to 2.54 GHz, and the radiation pattern stay the same in the entire band. The peak gain of the antenna can reach 8.27 dB.
A Tm laser pumped Mid-IR all solid-state laser is reported. A thulium laser is used to directly drive a ZnGeP2 optical parametric oscillator (OPO) with 1.99μm output to generate the 3~5μm wavelength. Diode pumped Tm...
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A Tm laser pumped Mid-IR all solid-state laser is reported. A thulium laser is used to directly drive a ZnGeP2 optical parametric oscillator (OPO) with 1.99μm output to generate the 3~5μm wavelength. Diode pumped Tm:YAP laser operates on 1.99μm, repetition frequency of 10KHz, the optical to optical conversion efficiency is 28%. The all solid-state Mid-IR laser runs at room temperature and achieves over 1W at 3~5μm with an optical to optical conversion efficiency of 5.4% starting from the pump diode.
In this paper, a broadband monopolar patch antenna is proposed. The epsilon negative (ENG) zeroth-order resonator (ZOR) is used to broaden the bandwidth of a monoplar patch antenna by combining two resonances together...
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In this paper, a broadband monopolar patch antenna is proposed. The epsilon negative (ENG) zeroth-order resonator (ZOR) is used to broaden the bandwidth of a monoplar patch antenna by combining two resonances together. The ENG ZOR antenna shares the patch and the ground plane with the monopopar patch antenna. The impedance bandwidth of the proposed antenna ranges from 0.89 to 3.95 GHz, and the gain of it is above 4.1 dB. This antenna has monopole-like radiation patterns over the whole bandwidth range.
This paper presents an novel compact broadband patch antenna loaded with Composite Left and Right-Handed Transmission Line (CLRH-TL) and Electromagnetic Band-Gap (EBG) structures. Many special properties of this type ...
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This paper presents an novel compact broadband patch antenna loaded with Composite Left and Right-Handed Transmission Line (CLRH-TL) and Electromagnetic Band-Gap (EBG) structures. Many special properties of this type of antenna relative to conventional one such like broad bandwidth or compact size or multi-frequency and so on are needed in more applications currently. Besides CLRH-TL can broaden bandwidth and reduce the antenna's size, it will bring in the disadvantage of low gain because it is realized by the gaps and vias. However EBG structure can reduce the surface wave and improve the realized gain of the antenna. So loading EBG structures in the ground can make up the drawback of low gain produced by CLRH-TL. The antenna achieved in this paper shows satisfactory characteristics, which are size reduction of 36% for the operation frequency 1.8 GHz, bandwidth of 20% and the peak gain of 3.187 dB.
An high-gain subwavelength cavity-based antenna based on metamaterial in L-band is presented in the discussion. The theory of subwavelength cavity is put forward firstly and its goods in the design of composite antenn...
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An high-gain subwavelength cavity-based antenna based on metamaterial in L-band is presented in the discussion. The theory of subwavelength cavity is put forward firstly and its goods in the design of composite antenna is widely applied. When grids of metal(copper) is located in period, some special properties can be taken such as the phase value of reflecting of the surface, which is always π when using PEC plate. The gain of the system is enhanced for this reason in L band. To overcome the disadvantage of narrow band of SRR rings, S-shaped structure of metamaterial is presented. The S-shaped slots etched on the patch is a shift of SRRs in the inherent plane. Furthermore, the underpart of the two groups of grids, which is regarded as partially reflective surface(PRS), is contacted with capacities. Such design is in favour of the promotion of the gain to 9.31 dB.
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