Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324)最新文献

Mobile speed estimation for TDMA-based hierarchical cellular systems 基于tdma的分层蜂窝系统移动速度估计

Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324) Pub Date : 2001-07-01 DOI: 10.1109/VETECF.1999.797379

Chengshan Xiao, K. D. Mann, J. Olivier

{"title":"Mobile speed estimation for TDMA-based hierarchical cellular systems","authors":"Chengshan Xiao, K. D. Mann, J. Olivier","doi":"10.1109/VETECF.1999.797379","DOIUrl":"https://doi.org/10.1109/VETECF.1999.797379","url":null,"abstract":"In this paper, a new algorithm is presented for estimating mobile speed for handoff in hierarchical cellular systems. The proposed algorithm contains six steps. Firstly, the instantaneous power of the received baseband signal is calculated to remove the frequency offset and data/speech information-bearing signals, while keeping the Doppler frequency information. Secondly, the calculated power signal is filtered using a lowpass linear phase finite impulse response (FIR) filter to suppress interference and noise. Thirdly, the filtered power signal is decimated to ease the computational burden, while the decimation factor is properly chosen to avoid frequency aliasing. Fourthly, autocorrelation values of the decimated filtered power signals are calculated on shifting slot by slot to suppress the \"slot burst frequency\" interference. Fifthly, the calculated autocorrelation values are normalized to suppress the power fluctuation of the received signals. Finally, the normalized autocorrelation values are compared with thresholds to estimate mobile speed. The simulation results indicate that the new algorithm works very well for both non-dispersive channels and dispersive channels to distinguish fast and slow moving mobiles. The method has very low latency, with results being available typically within one second after communication is established, and it can report estimation results every second or less.","PeriodicalId":355729,"journal":{"name":"Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133197015","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: 86

Channel assignment and layer selection in hierarchical cellular system with fuzzy control 基于模糊控制的分层元胞系统的信道分配与层选择

Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324) Pub Date : 2001-05-01 DOI: 10.1109/VETECF.1999.797375

C. Sung, K. Shum

{"title":"Channel assignment and layer selection in hierarchical cellular system with fuzzy control","authors":"C. Sung, K. Shum","doi":"10.1109/VETECF.1999.797375","DOIUrl":"https://doi.org/10.1109/VETECF.1999.797375","url":null,"abstract":"We consider a hierarchical system which consists of a macrolayer and a microlayer. The macrocells accommodate fast mobile users. However, if we direct too many mobile users to the macrocells, the system capacity is low. On the other hand, the microcells are designed to increase capacity, but they cause a large number of handoffs. Our aim is to maximize the system capacity while keeping the amount of handoff small. We minimize the handoff rate by a fuzzy layer selection algorithm which makes use of the past cell dwell times of a user and the channel occupancy of the target cell. To maximize the capacity, we propose a distributed channel assignment algorithm to dynamically allocate the channels among the two layers. Exchange of information is allowed between neighboring macrocells. The state of channel assignment in a macrocell and its interfering cells are tabulated in a channel allocation table, which provides all the information required in the integrated resource allocation scheme. The performance is evaluated by simulation and compared with the popular layer selection scheme known as the threshold method.","PeriodicalId":355729,"journal":{"name":"Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324)","volume":"137 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127497387","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: 20

Joint detection with low computational complexity for hybrid TD-CDMA systems TD-CDMA混合系统的低计算复杂度联合检测

Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324) Pub Date : 2001-02-01 DOI: 10.1109/VETECF.1999.797208

N. Benvenuto, G. Sostrato

引用次数: 31

Macrodiversity power control in hierarchical CDMA cellular systems 分层CDMA蜂窝系统中的宏分集功率控制

Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324) Pub Date : 2001-02-01 DOI: 10.1109/VETECF.1999.797372

John Y. Kim, Gordon L. Stüber, I. Akyildiz

引用次数: 32

A QoS-guaranteed fuzzy channel allocation controller for hierarchical cellular systems 分级元胞系统的qos保证模糊信道分配控制器

Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324) Pub Date : 2000-09-01 DOI: 10.1109/VETECF.1999.797374

Kuen-Rong Lo, Chung-Ju Chang, Cooper Chang, C. Shung

引用次数: 14

Computer simulation and measurement of error vector magnitude (EVM) and adjacent-channel power ratio (ACPR) for digital wireless communication RF power amplifiers 数字无线通信射频功率放大器误差矢量幅值(EVM)和邻接信道功率比(ACPR)的计算机仿真与测量

Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324) Pub Date : 1999-12-01 DOI: 10.1109/VETECF.1999.797292

Fu-Ling Lin, Shin-Fu Chen, Liang-Fang Chen, H. Chuang

{"title":"Computer simulation and measurement of error vector magnitude (EVM) and adjacent-channel power ratio (ACPR) for digital wireless communication RF power amplifiers","authors":"Fu-Ling Lin, Shin-Fu Chen, Liang-Fang Chen, H. Chuang","doi":"10.1109/VETECF.1999.797292","DOIUrl":"https://doi.org/10.1109/VETECF.1999.797292","url":null,"abstract":"Computer simulation and measurement of the error vector magnitude (EVM) and the adjacent channel power ratio (ACPR) of a 2.4 GHz MMIC power amplifier (PA) for digital wireless communications is presented. A computer simulation based on the /spl pi//4-DQPSK modulation with square-root raised cosine (SRRC) filter is established for this study. Using digital signal processing techniques and a time-domain approach, we can accurately predict the EVM and the ACPR related to the input power. The nonlinear effects of the MMIC PA are modeled as traditional nonlinearity parameters, such as 1-dB gain compression point or third-order intercept point IP3, by which the EVM and ACPR are simulated. A standard NADC modulated signal from a HP ESG-D signal generator is applied to the MMIC PA and the output signal analyzed by a HP 89410A vector signal analyzer. The measured results agree well with the simulation curves. This shows that the computer program by Matlab is useful to RF/microwave system engineers in the design of power amplifiers for digital wireless communications.","PeriodicalId":355729,"journal":{"name":"Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324)","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121462872","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: 15

Direction finding of broadband signals for frequency-selective fading channels 频选衰落信道宽带信号的测向

Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324) Pub Date : 1999-12-01 DOI: 10.1109/VETECF.1999.798439

M. Ghavami, R. Kohno

引用次数: 1

Non-collision packet reservation multiple access with random transmission to idle slot 非冲突包保留多路访问，随机传输到空闲插槽

Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324) Pub Date : 1999-12-01 DOI: 10.1109/VETECF.1999.801584

M. Tadenuma, I. Sasase

引用次数: 1

Computer simulation of human body effects on communication performance of a portable radio in urban mobile environments based on EVM and BER evaluation 基于EVM和误码率评估的城市移动环境下人体对便携式无线电通信性能影响的计算机模拟

Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324) Pub Date : 1999-12-01 DOI: 10.1109/VETECF.1999.797290

Fu-Ling Lin, H. Chuang

引用次数: 0

Radio source positioning using received time of arrival differences 利用接收到的到达时间差进行无线电源定位

Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324) Pub Date : 1999-12-01 DOI: 10.1109/VETECF.1999.797300

K. Itoh, S. Watanabe, T. Sato, Y. Hoshiko

引用次数: 5