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2007 European Conference on Wireless Technologies最新文献

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Concurrent, Reconfigurable, and Adaptable Oscillators For Multi-Band Multi-Mode Communication Systems 用于多频带多模式通信系统的并发、可重构和自适应振荡器
2007 European Conference on Wireless Technologies Pub Date : 2007-12-17 DOI: 10.1109/ECWT.2007.4404004
U. Rohde, A. Poddar
{"title":"Concurrent, Reconfigurable, and Adaptable Oscillators For Multi-Band Multi-Mode Communication Systems","authors":"U. Rohde, A. Poddar","doi":"10.1109/ECWT.2007.4404004","DOIUrl":"https://doi.org/10.1109/ECWT.2007.4404004","url":null,"abstract":"This paper presents the design approach of RCO (reconfigurable concurrent oscillator) using MCPTR (multi-coupled planar transmission line resonators) that simultaneously generates two or more signals of different frequencies that eliminate the need of lossy switches for switching the frequency band, thereby improves the system throughput. The measured phase noise for band#1 (2250-2850 MHz) and band#2 (4600-5900 MHz) are typically better than -108 dBc/Hz at 100 kHz offset from the carrier respectively; and the topology can be extended for higher frequency band.","PeriodicalId":448587,"journal":{"name":"2007 European Conference on Wireless Technologies","volume":"294 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125750038","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}
引用次数: 4
Performance Evaluation of OFDMA RRM Algorithms with Spectrum Reuse 1 频谱复用OFDMA RRM算法的性能评价
2007 European Conference on Wireless Technologies Pub Date : 2007-12-17 DOI: 10.1109/ECWT.2007.4403982
D. Zarbouti, G. Tsoulos, D.I. Kaklaman
{"title":"Performance Evaluation of OFDMA RRM Algorithms with Spectrum Reuse 1","authors":"D. Zarbouti, G. Tsoulos, D.I. Kaklaman","doi":"10.1109/ECWT.2007.4403982","DOIUrl":"https://doi.org/10.1109/ECWT.2007.4403982","url":null,"abstract":"The scope of this paper is the presentation of simulation results concerning the performance of an OFDMA cellular system. Three different RRM (radio resource management) algorithms are applied on an OFDMA system with omni-directional antennas. The magnitude of comparison was achievable total data rate in downlink. Since users are considered to request various bit rates (BR), their spatial distribution according to the requested BR is also investigated. Finally, an insight on how these algorithms handle users of different requested rates is presented.","PeriodicalId":448587,"journal":{"name":"2007 European Conference on Wireless Technologies","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125037790","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}
引用次数: 1
Exploiting Low-Cost Directional Antennas in 2.4 GHz IEEE 802.15.4 Wireless Sensor Networks 2.4 GHz IEEE 802.15.4无线传感器网络中低成本定向天线的开发
2007 European Conference on Wireless Technologies Pub Date : 2007-12-17 DOI: 10.1109/ECWT.2007.4403985
G. Giorgetti, A. Cidronali, Sandeep K. S. Gupta, G. Manes
{"title":"Exploiting Low-Cost Directional Antennas in 2.4 GHz IEEE 802.15.4 Wireless Sensor Networks","authors":"G. Giorgetti, A. Cidronali, Sandeep K. S. Gupta, G. Manes","doi":"10.1109/ECWT.2007.4403985","DOIUrl":"https://doi.org/10.1109/ECWT.2007.4403985","url":null,"abstract":"Motivated by recent interest in directional antennas for WSNs, we propose a four-beam patch antenna (FBPA) designed to meet the size, cost and complexity constraints of sensor nodes. We use in-field experiments with COTS motes to demonstrate substantial benefits to WSN applications. Used outdoors, the FBPA extends the communication range from 140 m to more than 350 m, while indoors it suppresses the interference due to multipath fading by reducing the signal variability of more than 70%. We also show interference suppression from IEEE 802.11 g systems and discuss the use of the antenna as a form of angular diversity useful to cope with the variability of the radio signal. Experimental data are analyzed to derive model parameters intended for use in future network simulations.","PeriodicalId":448587,"journal":{"name":"2007 European Conference on Wireless Technologies","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130195879","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}
引用次数: 89
The Effect of Spatial Axial Ratio Variation on QPSK Modulation Encoded Using Orthogonal Circularly Polarized Signals 空间轴比变化对正交圆极化信号编码QPSK调制的影响
2007 European Conference on Wireless Technologies Pub Date : 2007-12-17 DOI: 10.1109/ECWT.2007.4403946
M. Amin, S. Ahmed, V. Fusco, H. Cantú, T. Ratnarajah
{"title":"The Effect of Spatial Axial Ratio Variation on QPSK Modulation Encoded Using Orthogonal Circularly Polarized Signals","authors":"M. Amin, S. Ahmed, V. Fusco, H. Cantú, T. Ratnarajah","doi":"10.1109/ECWT.2007.4403946","DOIUrl":"https://doi.org/10.1109/ECWT.2007.4403946","url":null,"abstract":"In this work, we show a new method which can directly encode an I (in-phase) and Q (quadrature-phase) baseband data stream onto a circularly polarized (CP) microwave signal. Here I and Q components are fed directly into a two port CP antenna in order to yield right hand circular polarized (RHCP) or left hand circular polarized (LHCP) waveforms each encoded with zero or 180deg phase shift in order to effect QPSK modulation. The CP signal from such an antenna will have deterministic unequal amplitude and phase shifts at different far field spatial locations which if not compensated will degrade the bit-error-rate (BER) performance of the receiver. Simulation and experimental results show the BER performance of the receiver when these two orthogonal CP components have spatially induced phase differences or amplitude imbalances between them. The technique described allows a factor two reduction over the normal QPSK requirement by virtue of the polarization diversity inherent in the scheme.","PeriodicalId":448587,"journal":{"name":"2007 European Conference on Wireless Technologies","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130414705","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}
引用次数: 9
High Efficiency VHF Transmitters Based on Polar Modulator and Enhanced PWM Power Converter 基于极性调制器和增强型PWM功率变换器的高效甚高频发射机
2007 European Conference on Wireless Technologies Pub Date : 2007-12-17 DOI: 10.1109/ECWT.2007.4403939
A. Alimenti, A. Gesano, P. Nocito, D. Pezzetta
{"title":"High Efficiency VHF Transmitters Based on Polar Modulator and Enhanced PWM Power Converter","authors":"A. Alimenti, A. Gesano, P. Nocito, D. Pezzetta","doi":"10.1109/ECWT.2007.4403939","DOIUrl":"https://doi.org/10.1109/ECWT.2007.4403939","url":null,"abstract":"This paper focuses on the design solutions needed to improve the global power efficiency of a VHF transmitter. The proposed approach is based on a polar modulation architecture and uses an enhanced PWM power converter (patent pending, PCT/IB2006/051827) to realize the envelope modulation. A custom algorithm is adopted to dynamically control the output envelope of the RF signal. In order to operate in real-time, the algorithm has been implemented in a FPGA. The AM to PM distortion of the polar transmitter has been carefully investigated and corrected exploiting either a feed-forward or a feed-back technique. As a result, a transmitter efficiency (final stage and amplitude modulator) of 62% was measured at 119 MHz for a 16 W average output power. In this experiment the VDL2 modulation standard was used (D8PSK modulation with lO.Sksps) obtaining an EVM of 0.30% and an ACPR less than -63 dBc. A final discussion on the possibility to export the proposed solutions to other RF communication systems and platforms is given.","PeriodicalId":448587,"journal":{"name":"2007 European Conference on Wireless Technologies","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129297037","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}
引用次数: 1
Small Size, High Gain and High F/B Ratio Patch Antenna Arranging Parasitic Element on the Back 小尺寸，高增益和高F/B比贴片天线布置在背后的寄生元件
2007 European Conference on Wireless Technologies Pub Date : 2007-12-17 DOI: 10.1109/EUMC.2007.4405370
O. Shibata, H. Koyama, T. Sawaya
{"title":"Small Size, High Gain and High F/B Ratio Patch Antenna Arranging Parasitic Element on the Back","authors":"O. Shibata, H. Koyama, T. Sawaya","doi":"10.1109/EUMC.2007.4405370","DOIUrl":"https://doi.org/10.1109/EUMC.2007.4405370","url":null,"abstract":"A small size patch antenna with high gain and high front-to-back (F/B) ratio has been newly developed. The antenna consists of two elements, that is, RF exiting element arranging on the front side and parasitic one on the back. The latter is terminated by the reactance. The antenna is as small as 80x80x8 mm in size and shows the gain and F/B ratio of 6 dBi and 15 dB at 950 MHz band, respectively. The obtained results are about 2 dB and 10 dB higher in gain and F/B ratio, respectively as compared with the conventional patch antenna. The size dependence of the performance has been investigated for antenna design by the simulation. The result shows that decreasing the element width with sacrificing the increase of thickness is found to be effective for minimizing the antenna volume.","PeriodicalId":448587,"journal":{"name":"2007 European Conference on Wireless Technologies","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131129583","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}
引用次数: 4
Complex-Weighted OFDM Transmission with Low PAPR 低PAPR的复加权OFDM传输
2007 European Conference on Wireless Technologies Pub Date : 2007-12-17 DOI: 10.1109/ECWT.2007.4403932
H. Nikookar, D. Soehartono
{"title":"Complex-Weighted OFDM Transmission with Low PAPR","authors":"H. Nikookar, D. Soehartono","doi":"10.1109/ECWT.2007.4403932","DOIUrl":"https://doi.org/10.1109/ECWT.2007.4403932","url":null,"abstract":"In this paper the novel method of complex weighting for peak-to-average power (PAPR) reduction of OFDM signal is addressed. Combination of different amplitude weighting factors (including rectangular, Bartlett, Gaussian, raised cosine, half-sin, Shannon, and subcarrier masking) with phasing of each OFDM subcarrier using random phase updating algorithm is studied. The impact of complex weighting of OFDM signal on the PAPR reduction is investigated by means of simulation and is compared for the above mentioned weighting factors. Results show that by either amplitude weighting or random phase updating the PAPR can be reduced. Applying both techniques together will further reduce the PAPR For an OFDM system with 32 subcarriers and by Gaussian weighting combined with random phase updating, a PAPR reduction gain of 3.2 dB can be achieved. In order to reduce the complexity, grouping of amplitude weighting and/or phasing is applied. Results show that grouping of amplitudes weighting and phases reduces the hardware complexity while not much impacting the PAPR reduction gain of the method. For even further reduction of the PAPR, complex weighting method with dynamic threshold is investigated. Results show that the PAPR can be further reduced by factor of 4.8 dB.","PeriodicalId":448587,"journal":{"name":"2007 European Conference on Wireless Technologies","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132911315","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}
引用次数: 4
Spatio-Temporal Availability in Satellite-to-Indoor Broadcasting 卫星到室内广播的时空可用性
2007 European Conference on Wireless Technologies Pub Date : 2007-12-17 DOI: 10.1109/ECWT.2007.4403971
M. Milojević, G. del Galdo, Nuan Song, M. Haardt, A. Heuberger
{"title":"Spatio-Temporal Availability in Satellite-to-Indoor Broadcasting","authors":"M. Milojević, G. del Galdo, Nuan Song, M. Haardt, A. Heuberger","doi":"10.1109/ECWT.2007.4403971","DOIUrl":"https://doi.org/10.1109/ECWT.2007.4403971","url":null,"abstract":"This contribution studies the spatio-temporal availability of satellite links inside typical indoor environments. The spatio-temporal satellite-to-indoor channels are obtained by a 3D ray tracing engine and by a geometry-based channel modeling tool. In this paper the temporal fluctuations of the channels have been modeled based on satellite-to-indoor measurements. Here the performance of single as well as multiple receive antennas with different polarimetric radiation patterns are compared for different satellite elevation angles. The results show that additional antennas placed at the receiver reduce both the spatial and temporal variability of the received power, leading to a significant reduction in transmit power necessary for the same target availability.","PeriodicalId":448587,"journal":{"name":"2007 European Conference on Wireless Technologies","volume":"106 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133814505","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}
引用次数: 4
A 28 mW, 1.5 V GPS receiver in 0.25 μm silicon-on-sapphire CMOS process 采用0.25 μm蓝宝石上硅CMOS工艺的28mw, 1.5 V GPS接收机
2007 European Conference on Wireless Technologies Pub Date : 2007-12-17 DOI: 10.1109/ECWT.2007.4404019
J. Adamski, D. Losser, N. Dan, T. Kuramochi, K. Fujita, G. Pucci
{"title":"A 28 mW, 1.5 V GPS receiver in 0.25 μm silicon-on-sapphire CMOS process","authors":"J. Adamski, D. Losser, N. Dan, T. Kuramochi, K. Fujita, G. Pucci","doi":"10.1109/ECWT.2007.4404019","DOIUrl":"https://doi.org/10.1109/ECWT.2007.4404019","url":null,"abstract":"This paper describes a 28 mW, 1.5 V Global Positioning System (GPS) radio receiver chip implemented in a 0.25 μm silicon-on-sapphire CMOS process. The receiver uses a low IF architecture and achieves a cascaded noise figure of 3.5 dB including the RF SAW filter. The design takes advantage of the matching network integration capabilities and superb isolation properties of Peregrine's UltraCMOStrade silicon-on-sapphire process technology.","PeriodicalId":448587,"journal":{"name":"2007 European Conference on Wireless Technologies","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115722154","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}
引用次数: 1
Body Surface Backed Flexible Antennas for 17 GHz Wireless Body Area Networks Sensor Applications 用于17 GHz无线体域网络传感器应用的体表背置柔性天线
2007 European Conference on Wireless Technologies Pub Date : 2007-12-17 DOI: 10.1109/ECWT.2007.4403944
Shi Cheng, E. Ojefors, P. Hallbjorner, S. Ogden, J. Margell, K. Hjort, A. Rydberg
{"title":"Body Surface Backed Flexible Antennas for 17 GHz Wireless Body Area Networks Sensor Applications","authors":"Shi Cheng, E. Ojefors, P. Hallbjorner, S. Ogden, J. Margell, K. Hjort, A. Rydberg","doi":"10.1109/ECWT.2007.4403944","DOIUrl":"https://doi.org/10.1109/ECWT.2007.4403944","url":null,"abstract":"Body surface backed single and multiple notch antennas for 17 GHz on body wireless sensor communications are presented in this paper. The proposed antennas are designed to excite both body surface wave propagations and off body radiations, which are strictly required by wireless body area networks (WBAN) sensor communications. To realize those propagations and radiations, human body surface is utilized as a reflector for the antennas. The presented antennas fabricated on 100 um thick polyimide flexible laminates are numerically and experimentally studied both in free space and on real body surface, and the body effects on antenna impedance and radiation performance are also analyzed. Good agreements between simulations and measurements are achieved. It is shown that the proposed antennas feature about 10% impedance bandwidth (S11 = -10 dB) and higher than 3.7 dBi gain in free space. The antenna resonant frequencies are slightly detuned and the antenna gain is increased when they are placed close to body surface. Moreover, the surface wave propagations and radiations off body surface are also investigated by measuring transmissions between two identical single and multiple notch antennas on body surface, respectively.","PeriodicalId":448587,"journal":{"name":"2007 European Conference on Wireless Technologies","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116376173","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}
引用次数: 4
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