Pub Date : 2000-09-24DOI: 10.1109/VETECF.2000.886290
D. Mcnamara, M. Beach, P. Karlsson, P. Fletcher
Previous theoretical studies have demonstrated the substantial capacity or diversity gains possible when multi-element arrays are employed at both a transmitter and receiver. This is only possible when the radio channel exhibits sufficient scattering to induce independent fading at each receive element. An appreciation of both the temporal and spatial variation of such multiple-input, multiple-output (MIMO) channels is therefore required in order to investigate the performance of this architecture in real environments. In this paper we present initial results from indoor MIMO channel measurements taken within the coherence time of the channel. It is shown how capacity analysis of the MIMO channel response matrix alone can be misleading and how the combination of the variation of this with signal to noise ratio in real environments is particularly important.
{"title":"Initial characterisation or multiple-input multiple-output (MIMO) channels for space-time communication","authors":"D. Mcnamara, M. Beach, P. Karlsson, P. Fletcher","doi":"10.1109/VETECF.2000.886290","DOIUrl":"https://doi.org/10.1109/VETECF.2000.886290","url":null,"abstract":"Previous theoretical studies have demonstrated the substantial capacity or diversity gains possible when multi-element arrays are employed at both a transmitter and receiver. This is only possible when the radio channel exhibits sufficient scattering to induce independent fading at each receive element. An appreciation of both the temporal and spatial variation of such multiple-input, multiple-output (MIMO) channels is therefore required in order to investigate the performance of this architecture in real environments. In this paper we present initial results from indoor MIMO channel measurements taken within the coherence time of the channel. It is shown how capacity analysis of the MIMO channel response matrix alone can be misleading and how the combination of the variation of this with signal to noise ratio in real environments is particularly important.","PeriodicalId":186198,"journal":{"name":"Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131835650","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}
Pub Date : 2000-09-24DOI: 10.1109/VETECF.2000.886856
R. Sanchez-Perez, F. J. Casajús-Quirós
A simplification of the maximum likelihood sequence detector (MLSD) algorithm with zero decision delay is presented for GMSK receivers based on limiter discriminator in a frequency selective fading environment. Good performance is obtained when the detector employs side envelope information.
{"title":"Simple nonlinear GMSK receiver for multipath environment","authors":"R. Sanchez-Perez, F. J. Casajús-Quirós","doi":"10.1109/VETECF.2000.886856","DOIUrl":"https://doi.org/10.1109/VETECF.2000.886856","url":null,"abstract":"A simplification of the maximum likelihood sequence detector (MLSD) algorithm with zero decision delay is presented for GMSK receivers based on limiter discriminator in a frequency selective fading environment. Good performance is obtained when the detector employs side envelope information.","PeriodicalId":186198,"journal":{"name":"Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115402395","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}
Pub Date : 2000-09-24DOI: 10.1109/VETECF.2000.886102
Lin Ma, Z. Rong
cdma2000 is an IS-95 based third generation standard that will provide high data rate services through packet data connection. We analyze the performances of cdma2000 packet data services through a simulation study. The simulation model and methodology are described and the packet scheduling schemes are illustrated. The performance results in terms of throughput and delay for packet data rates up to 76.8 kbps in various channel environments are presented and analyzed. The spectrum efficiency results for turbo code and convolutional code are provided and discussed.
{"title":"Capacity simulations and analysis for cdma2000 packet data services","authors":"Lin Ma, Z. Rong","doi":"10.1109/VETECF.2000.886102","DOIUrl":"https://doi.org/10.1109/VETECF.2000.886102","url":null,"abstract":"cdma2000 is an IS-95 based third generation standard that will provide high data rate services through packet data connection. We analyze the performances of cdma2000 packet data services through a simulation study. The simulation model and methodology are described and the packet scheduling schemes are illustrated. The performance results in terms of throughput and delay for packet data rates up to 76.8 kbps in various channel environments are presented and analyzed. The spectrum efficiency results for turbo code and convolutional code are provided and discussed.","PeriodicalId":186198,"journal":{"name":"Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152)","volume":"219 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115734165","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}
Pub Date : 2000-09-24DOI: 10.1109/VETECF.2000.886786
Eunjung Kim, D. Cho
As broadband multimedia services and wireless services become popular, it is believed that ATM is widely accepted as a backbone network. In a small cell radius structure, handover occurs more frequently as the mobile base station moves. Therefore, it is necessary to have high-speed handover control. To support network mobility, we introduce a new optimum handover scheme using the overlayered tree structure based on the virtual connection tree (VCT) for handover involving several call connections. The handover delay could be then reduced. We describe ATM signaling capabilities supporting this scheme and present UNI/NNI protocol extensions. According to simulation results of the static and proposed adaptive VCT schemes in the case of a mobile network, the proposed scheme has a smaller handover delay compared with conventional schemes.
{"title":"An adaptive VCT based handoff scheme for mobile base station in wireless ATM network","authors":"Eunjung Kim, D. Cho","doi":"10.1109/VETECF.2000.886786","DOIUrl":"https://doi.org/10.1109/VETECF.2000.886786","url":null,"abstract":"As broadband multimedia services and wireless services become popular, it is believed that ATM is widely accepted as a backbone network. In a small cell radius structure, handover occurs more frequently as the mobile base station moves. Therefore, it is necessary to have high-speed handover control. To support network mobility, we introduce a new optimum handover scheme using the overlayered tree structure based on the virtual connection tree (VCT) for handover involving several call connections. The handover delay could be then reduced. We describe ATM signaling capabilities supporting this scheme and present UNI/NNI protocol extensions. According to simulation results of the static and proposed adaptive VCT schemes in the case of a mobile network, the proposed scheme has a smaller handover delay compared with conventional schemes.","PeriodicalId":186198,"journal":{"name":"Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152)","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124393130","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}
Pub Date : 2000-09-24DOI: 10.1109/VETECF.2000.886321
M.J. Lopez, K. Zangi, Jung-Fu Chen
We present a computationally efficient soft-output equalizer for communication over dispersive channels. The proposed equalizer has a forward and backward recursion structure similar to the classic BCJR MAP algorithm, but its complexity is reduced by constructing a reduced-state trellis, as in the decision feedback sequence estimator (DFSE). We are able to achieve consistent state definitions by running the backward pass on the same trellis as the forward pass. The performance of this reduced-complexity equalizer is evaluated within an iterative receiver in which the intersymbol interference (ISI) channel and channel code are treated as serially concatenated codes. The EDGE air interface is used as an illustrative example, for which we are able to reduce the number of states from 4096 to 8.
{"title":"Reduced-complexity MAP equalizer for dispersive channels","authors":"M.J. Lopez, K. Zangi, Jung-Fu Chen","doi":"10.1109/VETECF.2000.886321","DOIUrl":"https://doi.org/10.1109/VETECF.2000.886321","url":null,"abstract":"We present a computationally efficient soft-output equalizer for communication over dispersive channels. The proposed equalizer has a forward and backward recursion structure similar to the classic BCJR MAP algorithm, but its complexity is reduced by constructing a reduced-state trellis, as in the decision feedback sequence estimator (DFSE). We are able to achieve consistent state definitions by running the backward pass on the same trellis as the forward pass. The performance of this reduced-complexity equalizer is evaluated within an iterative receiver in which the intersymbol interference (ISI) channel and channel code are treated as serially concatenated codes. The EDGE air interface is used as an illustrative example, for which we are able to reduce the number of states from 4096 to 8.","PeriodicalId":186198,"journal":{"name":"Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152)","volume":"239 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114474885","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}
Pub Date : 2000-09-24DOI: 10.1109/VETECF.2000.886322
J. Sun, I. Reed
The error rates of MDPSK, coherent MPSK and noncoherent MFSK over slow flat, Rician fading channels are derived when linear diversity combining is applied to combat degradation due to fading. These closed-form solutions are sufficiently simple so that no approximations are needed for the numerical computations and general enough to include several cases of non-diversity, AWGN (the non-fading mode), Rayleigh fading, mixtures of Rayleigh and Rician fading (the mixed mode), and Rician fading. Error probabilities are graphically displayed for these different modulation schemes. The dependence of the power efficiency on the order of the diversity is plotted and examined for various values of M and a range of values of the Rician parameter K, the channel specular-to-scatter ratio for the measured statistics of mobile wireless channels. The analytical results presented are expected to provide much needed information for radio systems design and the evaluation of performance over fading channels when diversity reception is applied.
采用线性分集组合的方法，推导了在缓慢平坦、线性衰落信道中，MDPSK、相干MPSK和非相干MFSK的误码率。这些封闭形式的解足够简单，以至于数值计算不需要近似值，并且足够通用，可以包括非分集、AWGN(非衰落模式)、瑞利衰落、瑞利和瑞利的混合衰落(混合模式)和瑞利衰落等几种情况。这些不同调制方案的误差概率以图形方式显示。绘制了功率效率对分集顺序的依赖关系，并对各种M值和移动无线信道测量统计量的通道镜面散射比(channel specular- or -scatter ratio)的参数K的范围进行了检验。所提出的分析结果有望为无线电系统设计和在衰落信道中应用分集接收时的性能评估提供必要的信息。
{"title":"Mobile radio multi-link analysis","authors":"J. Sun, I. Reed","doi":"10.1109/VETECF.2000.886322","DOIUrl":"https://doi.org/10.1109/VETECF.2000.886322","url":null,"abstract":"The error rates of MDPSK, coherent MPSK and noncoherent MFSK over slow flat, Rician fading channels are derived when linear diversity combining is applied to combat degradation due to fading. These closed-form solutions are sufficiently simple so that no approximations are needed for the numerical computations and general enough to include several cases of non-diversity, AWGN (the non-fading mode), Rayleigh fading, mixtures of Rayleigh and Rician fading (the mixed mode), and Rician fading. Error probabilities are graphically displayed for these different modulation schemes. The dependence of the power efficiency on the order of the diversity is plotted and examined for various values of M and a range of values of the Rician parameter K, the channel specular-to-scatter ratio for the measured statistics of mobile wireless channels. The analytical results presented are expected to provide much needed information for radio systems design and the evaluation of performance over fading channels when diversity reception is applied.","PeriodicalId":186198,"journal":{"name":"Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114819061","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}
Pub Date : 2000-09-24DOI: 10.1109/VETECF.2000.886300
Weiguang Hou, H. M. Kwon
An antenna array is applied to a multiple access interference (MAI) suppression receiver to filter out the interfering signals that are spatially separated from the desired user. Also a novel adaptive direction-of-arrival (DOA) tracking algorithm is introduced under the assumption that the desired signal power is large enough compared to each of the interfering signals at the receiver after the PN despread. The adaptive DOA tracking algorithm requires only the first order statistics of the MAI and additive white Gaussian noise (AWGN). No matrix operation is required. Hence, the tracking algorithm is simple and has a low computational burden. Only 2M multiplications and 2(M-1) additions are required per snapshot for M number of antenna elements. Simulation results in a binary phase shift keying (BPSK) communication system with MAI suppression receiver under AWGN and Rayleigh fading environments are provided to show the tracking capability of the proposed tracking algorithm and the performance improvement of the proposed system.
{"title":"Interference suppression receiver with adaptive antenna array for code division multiple access communications systems","authors":"Weiguang Hou, H. M. Kwon","doi":"10.1109/VETECF.2000.886300","DOIUrl":"https://doi.org/10.1109/VETECF.2000.886300","url":null,"abstract":"An antenna array is applied to a multiple access interference (MAI) suppression receiver to filter out the interfering signals that are spatially separated from the desired user. Also a novel adaptive direction-of-arrival (DOA) tracking algorithm is introduced under the assumption that the desired signal power is large enough compared to each of the interfering signals at the receiver after the PN despread. The adaptive DOA tracking algorithm requires only the first order statistics of the MAI and additive white Gaussian noise (AWGN). No matrix operation is required. Hence, the tracking algorithm is simple and has a low computational burden. Only 2M multiplications and 2(M-1) additions are required per snapshot for M number of antenna elements. Simulation results in a binary phase shift keying (BPSK) communication system with MAI suppression receiver under AWGN and Rayleigh fading environments are provided to show the tracking capability of the proposed tracking algorithm and the performance improvement of the proposed system.","PeriodicalId":186198,"journal":{"name":"Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114827304","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}
Pub Date : 2000-09-24DOI: 10.1109/VETECF.2000.887056
Minyi Zhao, A. Akansu
We present a general optimization method of rate allocation for embedded image sources over fading channels under unequal error protection (UEP). 2-state Markov chain or Gilbert-Elliott (G-E) channel models are exploited to approximate slowly fading channels in wireless communications in which each state corresponds to a binary symmetric channel (BSC). Under the assumption that exact knowledge of the channel state information (CSI) is not available, the partition of the bit stream, the allocation of source/channel coding rate, and the number of protection levels for UEP schemes are all optimized by using the statistics of the G-E models and maximization of the expected error-free source bit stream length. Experiment results lead to different rate allocation strategies from previous ones in some channel conditions and the performance improvement is up to 0.4 dB.
{"title":"UEP of progressive images in wireless channels","authors":"Minyi Zhao, A. Akansu","doi":"10.1109/VETECF.2000.887056","DOIUrl":"https://doi.org/10.1109/VETECF.2000.887056","url":null,"abstract":"We present a general optimization method of rate allocation for embedded image sources over fading channels under unequal error protection (UEP). 2-state Markov chain or Gilbert-Elliott (G-E) channel models are exploited to approximate slowly fading channels in wireless communications in which each state corresponds to a binary symmetric channel (BSC). Under the assumption that exact knowledge of the channel state information (CSI) is not available, the partition of the bit stream, the allocation of source/channel coding rate, and the number of protection levels for UEP schemes are all optimized by using the statistics of the G-E models and maximization of the expected error-free source bit stream length. Experiment results lead to different rate allocation strategies from previous ones in some channel conditions and the performance improvement is up to 0.4 dB.","PeriodicalId":186198,"journal":{"name":"Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115007244","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}
Pub Date : 2000-09-24DOI: 10.1109/VETECF.2000.887101
T. Nishimura, Y. Tanabe, T. Ohgane, Y. Ogawa, Y. Doi, J. Kitakado
In SDMA, a spatial domain interference canceler applying a multistage processing concept to the MMSE multibeam adaptive array has an attractive feature that weak power signals can be detected in the successive stages after removing other strong power signals which are already detected. This idea can be enhanced to the reference timing estimation required in the MMSE algorithm. In this paper the spatial domain interference canceler introducing multistage timing estimation is proposed and its performance is evaluated by computer simulations. The results show that the timing estimation performance is highly improved.
{"title":"Spatial domain interference canceler using multistage adaptive array with precise timing estimation","authors":"T. Nishimura, Y. Tanabe, T. Ohgane, Y. Ogawa, Y. Doi, J. Kitakado","doi":"10.1109/VETECF.2000.887101","DOIUrl":"https://doi.org/10.1109/VETECF.2000.887101","url":null,"abstract":"In SDMA, a spatial domain interference canceler applying a multistage processing concept to the MMSE multibeam adaptive array has an attractive feature that weak power signals can be detected in the successive stages after removing other strong power signals which are already detected. This idea can be enhanced to the reference timing estimation required in the MMSE algorithm. In this paper the spatial domain interference canceler introducing multistage timing estimation is proposed and its performance is evaluated by computer simulations. The results show that the timing estimation performance is highly improved.","PeriodicalId":186198,"journal":{"name":"Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152)","volume":"191 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114984882","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}
Pub Date : 2000-09-24DOI: 10.1109/VETECF.2000.886788
A. Stirling
With the explosion in mobile telecommunications and increasing competition, mobile telephone service providers and vehicle makers are looking to develop new types of services for vehicle users. So far the services have included information about traffic conditions and support in case of breakdowns. In future digital broadcast and third generation telecommunication systems will be used to deliver interactive multimedia services into the vehicle. This paper looks at platform requirements for supporting the delivery of the new multimedia services. It considers the role of operating systems and networks in determining the flexibility and costs of the system.
{"title":"Mobile multimedia platforms","authors":"A. Stirling","doi":"10.1109/VETECF.2000.886788","DOIUrl":"https://doi.org/10.1109/VETECF.2000.886788","url":null,"abstract":"With the explosion in mobile telecommunications and increasing competition, mobile telephone service providers and vehicle makers are looking to develop new types of services for vehicle users. So far the services have included information about traffic conditions and support in case of breakdowns. In future digital broadcast and third generation telecommunication systems will be used to deliver interactive multimedia services into the vehicle. This paper looks at platform requirements for supporting the delivery of the new multimedia services. It considers the role of operating systems and networks in determining the flexibility and costs of the system.","PeriodicalId":186198,"journal":{"name":"Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152)","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116166228","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：