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.
Two-dimensional fuzzy temperature controller was used in the system of inverter air-conditioner to control the room temperature. Self-adjustment PID fuzzy controller was proposed to realize real-time control funct...
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Two-dimensional fuzzy temperature controller was used in the system of inverter air-conditioner to control the room temperature. Self-adjustment PID fuzzy controller was proposed to realize real-time control function. V / F control mode was used to compensate with low voltage, the average sampling algorithm was proposed to implement SPWM waveform modulation. Finally, the feasibility of self-adjustment PID fuzzy controller was verified by simulation, the actual operation results had proved that self-adjustment PID fuzzy controller had reliable, good output waveform and small harmonic wave, which could meet operational requirements of inverter air-conditioner.
In this paper, the system of variable frequency speed-regulation based on PLC was proposed. Firstly, the overall structure of control system was determined. Inverter and programmable logic controller were chosen to co...
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In this paper, the system of variable frequency speed-regulation based on PLC was proposed. Firstly, the overall structure of control system was determined. Inverter and programmable logic controller were chosen to complete variable frequency speed-regulation. Secondly, parameters of inverter were set by develop system hardware. PLC drive selection and I/0 points distribution were completed; rotary encoder was connected with PLC interface. Finally, the software flow charts and ladder programs were designed by analysis of elevator system on the basis of software design methods.
Two-dimensional fuzzy temperature controller was used to control the room temperature in the system of inverter air-conditioner,self-adjustment PID fuzzy controller was proposed to realize the function of real-time **...
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ISBN:
(纸本)9781612848334
Two-dimensional fuzzy temperature controller was used to control the room temperature in the system of inverter air-conditioner,self-adjustment PID fuzzy controller was proposed to realize the function of real-time *** control mode of V /F was used to compensate with low *** average sampling algorithm was proposed to implement SPWM waveform ***,the feasibility of selfadjustment PID fuzzy controller was verified by simulation *** actual operation results had proved that selfadjustment PID fuzzy controller had reliable,good output waveform and small harmonic wave,which could meet operational requirements of inverter air-conditioner.
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.
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.
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.
A novel technique of noise suppression based on singular value decomposition (SVD) algorithm for a UWB system with Time hopping (TH) and pulse amplitude modulation (PAM) are considered is presented in this paper,. Acc...
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A novel technique of noise suppression based on singular value decomposition (SVD) algorithm for a UWB system with Time hopping (TH) and pulse amplitude modulation (PAM) are considered is presented in this paper,. According to the different correlation about UWB signals and Gaussian noises respectively, SVD is used to approximate the noises which then are subtracted from the received signals. Aiming at shortcomings of existing singular value truncation criterion, this paper use a new method to decide the threshold for SVD filter (SVDF), based on the value of signal to noise ratio (SNR). Simulations have demonstrated that an efficient elimination of noise on UWB signal and an improvement on Bit error rate (BER) are achieved by comparing our algorithm with the EMD method.
In this paper, a novel denoising technique based on singular value decomposition (SVD) algorithm for a UWB system with Time hopping (TH) and pulse position modulation (PPM) are considered is presented. According t...
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In this paper, a novel denoising technique based on singular value decomposition (SVD) algorithm for a UWB system with Time hopping (TH) and pulse position modulation (PPM) are considered is presented. According to the different correlation about UWB signals and Gaussian noises themselves, SVD is used to approximate the noises which then are subtracted from the received signals. Aiming at shortcomings of existing singular value truncation criterion, this paper use a new method to decide the threshold for SVD filter (SVDF), based on the value of signal to noise ratio (SNR). Simulations have demonstrated that an efficient elimination of noise on UWB signal and an improvement on Bit error rate (BER) are achieved by comparing our algorithm with the EMD method.
Introduced the rule of choosing second harmonic generation (SHG) crystals, designed a TEA CO 2 laser SHG path using ZGP, studied the thermal load of ZGP and optimized the parameter.
Introduced the rule of choosing second harmonic generation (SHG) crystals, designed a TEA CO 2 laser SHG path using ZGP, studied the thermal load of ZGP and optimized the parameter.
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