{"title":"Double-null pattern synthesis for low-angle tracking","authors":"Jian-hong Zhao, Jian-yu Yang","doi":"10.1109/ICMMT.2007.381282","DOIUrl":"https://doi.org/10.1109/ICMMT.2007.381282","url":null,"abstract":"In omnidirectional array, when tracking low elevation targets, conventional difference pattern is suffered from the multipath echoes and the resulted target elevation angle will oscillate evenly point at the image target direction. Double-null difference pattern is a effective monopulse technique for low-angle tracking against low elevation multipath. Analyse why simple beam linear superposition from the published reference is not effective again to form double-null difference pattern in omnidirectional array, and put forward our synthesis method based on the reasonable constraint conditions and LS criteria to the constrained shaping weight-vector. Computer simulations using a 100-element LUA shown this double-null pattern synthesis technique is effective. Based on the under-determined constraint conditions, using LS to approximation to the original weight-vector can be seen as a new synthesis method for the constrained pattern.","PeriodicalId":409971,"journal":{"name":"2007 International Conference on Microwave and Millimeter Wave Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127243166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design and Optimization of a Compact Patch Antenna","authors":"X. Liu, Y.B. Chen, Y. Jiao, F. Zhang","doi":"10.1109/ICMMT.2007.381309","DOIUrl":"https://doi.org/10.1109/ICMMT.2007.381309","url":null,"abstract":"A compact patch antenna with limited length is designed in this paper. Design method combining modified particle swarm optimization with Zeland's IE3D is used to optimize the bandwidth of the compact antenna. A 75 MHz bandwidth is achieved for the compact patch antenna, and an 8.8 dBi gain is obtained. The optimized compact patch antenna has been fabricated and measured. Good agreement is observed between numerical and experimental results of the compact patch antenna.","PeriodicalId":409971,"journal":{"name":"2007 International Conference on Microwave and Millimeter Wave Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129937493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Combined Antenna Selection Algorithm in MIMO Systems","authors":"Wang Yang, Song Jiao, G. Lin-dong","doi":"10.1109/ICMMT.2007.381310","DOIUrl":"https://doi.org/10.1109/ICMMT.2007.381310","url":null,"abstract":"Antenna selection is used for increasing the channel capacity of multiple-input multiple-output (MIMO) systems, and reducing the systems complexity and RF chains cost. In this paper, we first study the capacities of MIMO systems, having different antenna assignments between the transmitter and receiver, and propose an optimum assignment from the viewpoint of maximizing the channel capacity. Considering the selections at both transmitter and receiver, the combined antenna selection algorithm is proposed based on the norm and correlation between rows and columns of the channel matrix. The proposed selection requires low computational complexity because of avoiding matrix operations. Simulation analysis and comparisons indicate that its performance is very close to the optimum combined selection, better than the optimum selection only at the receiver.","PeriodicalId":409971,"journal":{"name":"2007 International Conference on Microwave and Millimeter Wave Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129262634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Shielding Effectiveness of a Rectangular Enclosure with Aperture and Wire Penetration","authors":"S. Z. Sapuan, M. Jenu","doi":"10.1109/ICMMT.2007.381376","DOIUrl":"https://doi.org/10.1109/ICMMT.2007.381376","url":null,"abstract":"An enclosure without aperture and wire penetration are impracticable due to the requirement for ventilation and cables. This paper is written to present the measurement of shielding effectiveness (SE) and S21 for such enclosure at frequencies below 1 GHz. The measurement results indicate that a wire or cable penetrating into an enclosure has impact to the shielding effectiveness. The coupling between a wire penetration and a detector inside the enclosure show good agreement between experiment and simulation. All results indicate the same resonant frequency approximately 707.1 MHz for a 300 times 120 times 300 mm enclosure.","PeriodicalId":409971,"journal":{"name":"2007 International Conference on Microwave and Millimeter Wave Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122314777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"UWB Channel Modeling and Simulation","authors":"Xiaoguang Li, Zhengwei Du, Ke Gong, Zhenghe Feng","doi":"10.1109/ICMMT.2007.381387","DOIUrl":"https://doi.org/10.1109/ICMMT.2007.381387","url":null,"abstract":"It's important to establish an effective UWB indoor wave propagation model for designing a system. In this paper, we develop a 3-D UWB channel model using the ray tracing method in the time domain, based on ray mechanisms of geometrical optics (GO) and uniform geometrical theory of diffraction (UTD) in the time domain. According to the simulation results for an in-home channel, the following conclusions are obtained. To a single receiving point, the shape of the receiving signal depends on its position. To a certain receiving point, the receiving signal is stronger when the transmitting antenna is placed at the height of 1.5 m (the normal physiological height) rather than 2.9 m (almost up to the roof of the room). The receiving signals are stronger when the transmitting and receiving antennas are polarized in the same direction.","PeriodicalId":409971,"journal":{"name":"2007 International Conference on Microwave and Millimeter Wave Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124943371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Miao, F. Dauplay, Y. Delorme, J. Baubert, G. Beaudin, S. Shi
{"title":"Simulation of a Membrane Based Quasi-Optical Antenna at 2.5 THz","authors":"W. Miao, F. Dauplay, Y. Delorme, J. Baubert, G. Beaudin, S. Shi","doi":"10.1109/ICMMT.2007.381359","DOIUrl":"https://doi.org/10.1109/ICMMT.2007.381359","url":null,"abstract":"In this paper, we present a simulation on the radiation pattern and return loss of a membrane based quasi optical antenna at 2.5 THz. The integrated antenna consists of a planar twin slot antenna, a metallic back reflector and a parabolic mirror. We firstly optimized the parameters of the planar twin slot antenna by using the commercial package CST Microwave Studio (finite integration technique) and then validated the optimized results with two other commercial packages Ansoft HFSS (finite element method) and EMSS FEKO (method of moment). The effect of the parabolic mirror to the entire integrated antenna is also analyzed with FEKO by using the ray tracing approximation of physical optics. A near Gaussian beam with an HPBW of 2.55 degree and a side lobe level of -22 dB is obtained when the focal length of the parabolic mirror is optimized.","PeriodicalId":409971,"journal":{"name":"2007 International Conference on Microwave and Millimeter Wave Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125286764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design of Optically Controlled Microwave Switch for Reconfigurable Antenna Systems","authors":"Peng Liu, D. Zhao, Bing-Zhong Wang","doi":"10.1109/ICMMT.2007.381325","DOIUrl":"https://doi.org/10.1109/ICMMT.2007.381325","url":null,"abstract":"A novel optically controlled microwave switch has been designed for applications in reconfigurable antenna systems. This new configuration consists of a microstrip transmission line with a gap etched in the metal strip and two identical microstrip square open-loop resonators. A piece of silicon photoconductive dice is placed on the etched gap. With no optical illumination the switch exhibits a well-defined stopband. The isolation is about 53 dB at the resonant frequency of 11.65 GHz. When light is focused onto the silicon dice, the photoconductivity effect suppresses the bandstop characteristic and induces the switch at \"ON\" state. The simulation result shows that there is a distinct improvement of the isolation by 20 dB than the optically controlled switches previously reported.","PeriodicalId":409971,"journal":{"name":"2007 International Conference on Microwave and Millimeter Wave Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122478772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yan Ye, Taijun Liu, Xingbin Zeng, Jiaming He, C. Akyel
{"title":"Accurate Permittivity Measurement Using the Cavity Perturbation Technique at ISM 5.8GHz Radio Band","authors":"Yan Ye, Taijun Liu, Xingbin Zeng, Jiaming He, C. Akyel","doi":"10.1109/ICMMT.2007.381367","DOIUrl":"https://doi.org/10.1109/ICMMT.2007.381367","url":null,"abstract":"In this paper, a new calibration method with two-filling factors for the permittivity measurement is proposed. With this calibration method, it is not necessary to measure the volume of the small sample, which not only eliminates the measurement error of the sample volume, but also simplifies the measurement procedure. To improve the measurement accuracy, the Cursor method, the resonance curve area (RCA) method and the Lorentzian fit method are utilized to process the measured resonant curve data so as to obtain accurate resonant frequency and quality factor. Finally, the obtained permittivity measurement results of a liquid sample validate the accuracy of this permittivity measurement approach.","PeriodicalId":409971,"journal":{"name":"2007 International Conference on Microwave and Millimeter Wave Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132712730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On the Direct Calculation of UWB Impulse Signal Transmitting through a Finitely Conducting Slab","authors":"Wang Yang, Zhang Nai-tong","doi":"10.1109/ICMMT.2007.381344","DOIUrl":"https://doi.org/10.1109/ICMMT.2007.381344","url":null,"abstract":"A simplified closed-form analytic solution for UWB impulse signal transmitting through a finitely conducting slab is proposed in this paper. The approach requires first evaluating the impulse response of the slab and then convolving it with the specified incident field waveform. To obtain the impulsive transmitting field, either for vertical or horizontal polarization, approximations to the refraction coefficients and propagation loss, which can be approved to be accurate enough comparing with their frequency domain solutions, are made. Thereby, it permits simplified closed-form expressions in the time domain for both terms. The resulting transient response for the transmitting impulse field is then given by convolution of the time domain refraction coefficients and time domain propagation loss. A numerical example of incident monocycle transmitting though a slab using this technique is presented to illustrate the effective use of the method.","PeriodicalId":409971,"journal":{"name":"2007 International Conference on Microwave and Millimeter Wave Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133633432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Minghua Zhao, Yong Fan, Yonghong Zhang, Chengcheng Xie, J. Zhan
{"title":"A Nonlinear Circuit Model for Avalanche Diode in High Order Frequency Multiplication Mode","authors":"Minghua Zhao, Yong Fan, Yonghong Zhang, Chengcheng Xie, J. Zhan","doi":"10.1109/ICMMT.2007.381433","DOIUrl":"https://doi.org/10.1109/ICMMT.2007.381433","url":null,"abstract":"A nonlinear circuit model for avalanche diode is described in high order frequency multiplication mode. Based on the physical mechanism of avalanche diode, this model interprets the nonlinear harmonics character of avalanche effects. The simulation of nonlinear model predicts the high order harmonics generation capabilities of avalanche diodes. This prediction has been demonstrated by experimental results.","PeriodicalId":409971,"journal":{"name":"2007 International Conference on Microwave and Millimeter Wave Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134046630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}