首页 > 最新文献

The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.最新文献

英文 中文
Limitations in spectral efficiency of a rate-adaptive MIMO system utilizing pilot-aided channel prediction 利用导频辅助信道预测的速率自适应MIMO系统的频谱效率限制
Pub Date : 2003-04-22 DOI: 10.1109/VETECS.2003.1207547
B. Holter, G. Oien, K. Hole, H. Holm
A performance analysis of an adaptive modulation (ACM) system operating on a multiple-input multiple-output (MIMO) channel with uncorrelated Rayleigh fading subchannels is presented. Rate adaptation is based on periodically transmitted channel state information (CSI) back to the transmitter, providing information about the channel signal-to-noise ratio (CSNR) as predicted by the receiver. Transmit diversity is utilized by employing space-time block coding (STBC) at the transmitter.
提出了一种基于非相关瑞利衰落子信道的多输入多输出(MIMO)信道自适应调制系统的性能分析方法。速率自适应是基于周期性地将信道状态信息(CSI)发送回发射机,根据接收机的预测提供有关信道信噪比(CSNR)的信息。发射分集是通过在发射端采用空时分组编码(STBC)来实现的。
{"title":"Limitations in spectral efficiency of a rate-adaptive MIMO system utilizing pilot-aided channel prediction","authors":"B. Holter, G. Oien, K. Hole, H. Holm","doi":"10.1109/VETECS.2003.1207547","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207547","url":null,"abstract":"A performance analysis of an adaptive modulation (ACM) system operating on a multiple-input multiple-output (MIMO) channel with uncorrelated Rayleigh fading subchannels is presented. Rate adaptation is based on periodically transmitted channel state information (CSI) back to the transmitter, providing information about the channel signal-to-noise ratio (CSNR) as predicted by the receiver. Transmit diversity is utilized by employing space-time block coding (STBC) at the transmitter.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131146385","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: 12
Reliable wireless multicast using fast low-density codes 可靠的无线多播使用快速低密度代码
Pub Date : 2003-04-22 DOI: 10.1109/VETECS.2003.1207821
J. Chung, Sungeun Kim, J. Copeland
Recently, there has been the high demand for one-to-many reliable multicast distribution under wireless environments. The characteristics of multicast protocol combined with the inherent wireless channel impairment make the network performance drastically degrade as the group size or packet loss rate increases. Although the conventional Reed-Solomon FEC (forward error correction)-based scheme can mitigate problems such as NACK implosion and exposure, its computational complexity makes itself inappropriate for software implementation in resource-limited wireless device. We studied efficient wireless multicast protocol using low-density erasure codes known as tornado FEC and furthermore improved the encoding and decoding speed of tornado FEC by our novel interleaving technique without degrading its overall performance. We call new codes homogeneous tornado FEC (HTF). Our protocol scheme aims at a multicast bulk data distribution in wireless local area networks such as IEEE 802.11.
近年来,无线环境下对一对多可靠的组播分发的需求越来越大。组播协议的特性加上固有的无线信道损伤,使得网络性能随着组大小或丢包率的增加而急剧下降。尽管传统的基于Reed-Solomon前向纠错(FEC)的方案可以缓解NACK内爆炸和暴露等问题,但其计算复杂性使其不适合在资源有限的无线设备中实现软件。研究了利用龙卷风FEC这种低密度擦除码的高效无线组播协议,并在不影响龙卷风FEC整体性能的前提下,进一步提高了龙卷风FEC的编解码速度。我们称新代码为同质龙卷风FEC (HTF)。本协议方案的目标是在ieee802.11等无线局域网中实现组播批量数据分发。
{"title":"Reliable wireless multicast using fast low-density codes","authors":"J. Chung, Sungeun Kim, J. Copeland","doi":"10.1109/VETECS.2003.1207821","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207821","url":null,"abstract":"Recently, there has been the high demand for one-to-many reliable multicast distribution under wireless environments. The characteristics of multicast protocol combined with the inherent wireless channel impairment make the network performance drastically degrade as the group size or packet loss rate increases. Although the conventional Reed-Solomon FEC (forward error correction)-based scheme can mitigate problems such as NACK implosion and exposure, its computational complexity makes itself inappropriate for software implementation in resource-limited wireless device. We studied efficient wireless multicast protocol using low-density erasure codes known as tornado FEC and furthermore improved the encoding and decoding speed of tornado FEC by our novel interleaving technique without degrading its overall performance. We call new codes homogeneous tornado FEC (HTF). Our protocol scheme aims at a multicast bulk data distribution in wireless local area networks such as IEEE 802.11.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"05 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130692571","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: 0
Variable-rate OFDM systems with selective antenna diversity and adaptive modulation 具有选择性天线分集和自适应调制的变速率OFDM系统
Pub Date : 2003-04-22 DOI: 10.1109/VETECS.2003.1207605
M. Torabi, M. Soleymani
In this article, a new scheme consisting of a combination of adaptive modulation, orthogonal frequency division multiplexing (OFDM), high order space-frequency block coding (SFBC), and antenna selection is presented. The proposed scheme, exploits the benefits of space-frequency block codes, OFDM and adaptive modulation to provide high quality of transmission for wireless communications over frequency selective fading channels. We examine the spectral efficiency and coding gain advantages of the proposed system. It is shown that antenna selection with adaptive modulation can greatly improve the performance of the conventional SFBC-OFDM systems.
本文提出了一种由自适应调制、正交频分复用(OFDM)、高阶空频分组编码(SFBC)和天线选择相结合的新方案。该方案利用空频分组码、OFDM和自适应调制的优点,在频率选择性衰落信道上为无线通信提供高质量的传输。研究了该系统的频谱效率和编码增益优势。研究表明,采用自适应调制的天线选择可以大大提高传统的SFBC-OFDM系统的性能。
{"title":"Variable-rate OFDM systems with selective antenna diversity and adaptive modulation","authors":"M. Torabi, M. Soleymani","doi":"10.1109/VETECS.2003.1207605","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207605","url":null,"abstract":"In this article, a new scheme consisting of a combination of adaptive modulation, orthogonal frequency division multiplexing (OFDM), high order space-frequency block coding (SFBC), and antenna selection is presented. The proposed scheme, exploits the benefits of space-frequency block codes, OFDM and adaptive modulation to provide high quality of transmission for wireless communications over frequency selective fading channels. We examine the spectral efficiency and coding gain advantages of the proposed system. It is shown that antenna selection with adaptive modulation can greatly improve the performance of the conventional SFBC-OFDM systems.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132926955","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: 13
An improved 2-dimensional pilot-symbols assisted channel estimation in OFDM systems 一种改进的二维导频符号辅助OFDM系统信道估计方法
Pub Date : 2003-04-22 DOI: 10.1109/VETECS.2003.1207091
Z. Jianhua, Zhang Ping
In orthogonal frequency division multiplexing (OFDM) systems, the pilot-symbols (PS) are utilized to provide an accurate estimation of the channel response. Based on the channel response of PS, 2-dimensional Wiener filtering can provide the optimal channel estimation. However, for the shortage of PS the bit error rate (BER) performance of the side subcarriers obviously worse than that of the other subcarriers. In this paper the periodical character of the discrete time-frequency channel response in frequency domain is observed and the new frequency autocorrelation function (acf) with the periodical property is derived. Then it is applied to obtain the new coefficients of the Wiener filtering. Through the simulation it is verified that the 2-dimensional Wiener filtering based on the periodical frequency acf can efficiently enhance the accuracy of the channel estimation at side subcarriers and it is more accurate optimal PS assisted channel estimation scheme in discrete OFDM systems.
在正交频分复用(OFDM)系统中,利用导频符号(PS)来提供信道响应的精确估计。基于PS的信道响应,二维维纳滤波可以提供最优的信道估计。然而,由于PS不足,侧子载波的误码率(BER)性能明显低于其他子载波。本文观察了离散时频通道响应在频域的周期性,并推导了具有周期性的频率自相关函数(acf)。然后应用该方法求出维纳滤波的新系数。仿真结果表明,基于周期频率acf的二维维纳滤波能有效提高侧子载波信道估计的精度,是离散OFDM系统中更为精确的最优PS辅助信道估计方案。
{"title":"An improved 2-dimensional pilot-symbols assisted channel estimation in OFDM systems","authors":"Z. Jianhua, Zhang Ping","doi":"10.1109/VETECS.2003.1207091","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207091","url":null,"abstract":"In orthogonal frequency division multiplexing (OFDM) systems, the pilot-symbols (PS) are utilized to provide an accurate estimation of the channel response. Based on the channel response of PS, 2-dimensional Wiener filtering can provide the optimal channel estimation. However, for the shortage of PS the bit error rate (BER) performance of the side subcarriers obviously worse than that of the other subcarriers. In this paper the periodical character of the discrete time-frequency channel response in frequency domain is observed and the new frequency autocorrelation function (acf) with the periodical property is derived. Then it is applied to obtain the new coefficients of the Wiener filtering. Through the simulation it is verified that the 2-dimensional Wiener filtering based on the periodical frequency acf can efficiently enhance the accuracy of the channel estimation at side subcarriers and it is more accurate optimal PS assisted channel estimation scheme in discrete OFDM systems.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133490626","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: 8
Characterisation of the time-dependent urban MIMO channel in FDD communication systems FDD通信系统中时变城市MIMO信道的特性
Pub Date : 2003-04-22 DOI: 10.1109/VETECS.2003.1207601
J. Maurer, C. Waldschmidt, T. Kayser, W. Wiesbeck
The influence of the time dependent urban transmission channel on MIMO systems is investigated in this paper. Exploiting the full potential of MIMO systems requires the knowledge of the transmission channel matrix at the transmitter and the receiver. Channel estimation is therefore necessary. It has to be performed continuously as the transmission channel changes over time. In real communications systems it is only possible to update the channel state information in certain time intervals. During these intervals the estimated channel matrix is assumed to be constant. The difference between the real channel and the estimated one leads to non-orthogonal channels in the MIMO system. The result is inter-sub-channel interference (ISCI). The ISCI is considered as a Gaussian noise random process, which is added to the common thermal noise. Due to the increased total noise power of the resulting channel, the capacity decreases. Furthermore, a sub-channel transmission gain degradation (STGD) occurs caused by the non-orthogonal sub-channels. This results in an additional capacity loss. The dependency of ISCI and STGD on the update time interval is investigated. The considerations are based on simulations of the transmission channel in an urban environment. In order to attain realistic results, a 3D ray-tracing tool is used. An FDD communication system is assumed.
本文研究了时变城市传输信道对MIMO系统的影响。利用MIMO系统的全部潜力需要发射器和接收器的传输信道矩阵的知识。因此,信道估计是必要的。当传输信道随时间变化时,它必须连续执行。在实际的通信系统中,只能在一定的时间间隔内更新信道状态信息。在这些间隔期间,假定估计的信道矩阵是恒定的。在MIMO系统中,实际信道与估计信道之间的差异导致了信道的非正交。其结果是子信道间干扰(ISCI)。将ISCI视为一个高斯噪声随机过程,并将其加入到常见的热噪声中。由于产生的信道的总噪声功率增加,容量减小。此外,由于子信道不正交,导致子信道传输增益下降(STGD)。这将导致额外的容量损失。研究了ISCI和STGD对更新时间间隔的依赖关系。这些考虑是基于城市环境中传输信道的模拟。为了获得逼真的结果,使用了3D光线追踪工具。假设一个FDD通信系统。
{"title":"Characterisation of the time-dependent urban MIMO channel in FDD communication systems","authors":"J. Maurer, C. Waldschmidt, T. Kayser, W. Wiesbeck","doi":"10.1109/VETECS.2003.1207601","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207601","url":null,"abstract":"The influence of the time dependent urban transmission channel on MIMO systems is investigated in this paper. Exploiting the full potential of MIMO systems requires the knowledge of the transmission channel matrix at the transmitter and the receiver. Channel estimation is therefore necessary. It has to be performed continuously as the transmission channel changes over time. In real communications systems it is only possible to update the channel state information in certain time intervals. During these intervals the estimated channel matrix is assumed to be constant. The difference between the real channel and the estimated one leads to non-orthogonal channels in the MIMO system. The result is inter-sub-channel interference (ISCI). The ISCI is considered as a Gaussian noise random process, which is added to the common thermal noise. Due to the increased total noise power of the resulting channel, the capacity decreases. Furthermore, a sub-channel transmission gain degradation (STGD) occurs caused by the non-orthogonal sub-channels. This results in an additional capacity loss. The dependency of ISCI and STGD on the update time interval is investigated. The considerations are based on simulations of the transmission channel in an urban environment. In order to attain realistic results, a 3D ray-tracing tool is used. An FDD communication system is assumed.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133674697","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: 8
A unit with functions of spectrum monitoring, self-excitation detection and isolation degree test for wireless relay station 一种具有无线中继站频谱监测、自激检测和隔离度测试功能的装置
Pub Date : 2003-04-22 DOI: 10.1109/VETECS.2003.1207082
Sujian Zhao, Xin Su, Chu Zhang, Yan Yao
This paper proposes a practical plan for a unit with functions of spectrum monitoring, self-excitation detection and isolation degree test, which is suitable for current wireless relay station. Its design principles, signal processing algorithms and simulation results are given. This design plan leaves room for future functional extension, and does not perform large modifications to the original structure of the relay station.
本文提出了一种适用于当前无线中继站的具有频谱监测、自激检测和隔离度测试功能的装置的实用方案。给出了其设计原理、信号处理算法和仿真结果。该设计方案为未来的功能扩展留有空间,对中继站原有结构不作大的修改。
{"title":"A unit with functions of spectrum monitoring, self-excitation detection and isolation degree test for wireless relay station","authors":"Sujian Zhao, Xin Su, Chu Zhang, Yan Yao","doi":"10.1109/VETECS.2003.1207082","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207082","url":null,"abstract":"This paper proposes a practical plan for a unit with functions of spectrum monitoring, self-excitation detection and isolation degree test, which is suitable for current wireless relay station. Its design principles, signal processing algorithms and simulation results are given. This design plan leaves room for future functional extension, and does not perform large modifications to the original structure of the relay station.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134620382","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: 2
Variable spreading factor-OFCDM with two dimensional spreading that prioritizes time domain spreading for forward link broadband wireless access 可变扩频因子-二维扩频ofcdm,优先考虑前向链路宽带无线接入的时域扩频
Pub Date : 2003-04-22 DOI: 10.1109/VETECS.2003.1207516
N. Maeda, Y. Kishiyama, H. Atarashi, M. Sawahashi
This paper proposes the optimum design for adaptively controlling the spreading factor in orthogonal frequency and code division multiplexing (OFCDM) with two-dimensional spreading according to the cell configuration, channel load, and propagation channel conditions, assuming the adaptive modulation and channel coding (AMC) scheme employing QPSK and 16QAM data modulation. Furthermore, we propose a two-dimensional channelization code assignment scheme to achieve skillfully orthogonal multiplexing of multiple physical channels. Computer simulation results elucidate that bit-interleaving in the frequency domain is superior to chip-interleaving especially for a full channel load because bit-interleaving exhibits a large randomization effect of burst errors, while still maintaining code orthogonality. In time domain spreading, the optimum spreading factor, except for an extremely high mobility case such as for the fading maximum Doppler frequency f/sub D/ = 1500 Hz, becomes SF/sub Time/ = 16, and it should be decreased to SF/sub Time/ = 8 for such a very fast fading environment using 16QAM modulation. When the channel load is light such as C/sub mux//SF = 0.25 (C/sub mux/ and SF denote the number of multiplexed codes and total spreading factor, respectively), the required average received signal energy per symbol-to-background noise power spectrum density ratio (E/sub s//N/sub 0/) is reduced as the spreading factor in the frequency domain is increased up to say SF/sub Freq/ = 32 for QPSK and 16QAM modulation, respectively (Note that, nevertheless, 16QAm modulation under such a lighter channel load condition is replaced by QPSK modulation together with two fold the channel load as 16QAM to achieve the same information bit rate). Meanwhile, when the channel load is close to full such as when C/sub mux//SF = 0.94, the optimum spreading factor in the frequency domain is SF/sub Freq/ = 1 for 16QAM modulation and SF/sub Freq/ = 1 to 8 for QPSK modulation according to the delay spread. Consequently, by setting several combinations of spreading factors in the time and frequency domains, the near maximum link capacity is achieved both in cellular and hot-spot cell configurations assuming various channel conditions.
本文在采用QPSK和16QAM数据调制的自适应调制信道编码(AMC)方案下,根据小区结构、信道负荷和传播信道条件,提出了二维扩频正交频码分复用(OFCDM)扩频因子自适应控制的优化设计。此外,我们提出了一种二维信道化码分配方案,以实现多个物理信道的巧妙正交复用。计算机仿真结果表明,在频域中,比特交错优于芯片交错,特别是在全信道负载下,因为比特交错在保持码的正交性的同时,表现出很大的突发错误的随机化效应。在时域扩频方面,除了在诸如衰落最大多普勒频率f/sub / = 1500hz等极高迁移率的情况下,最佳扩频因子为SF/sub time / = 16,在使用16QAM调制的快速衰落环境下,最佳扩频因子应降至SF/sub time / = 8。当信道负载较轻时,如C/sub mux//SF = 0.25 (C/sub mux/和SF分别表示复用码数和总扩频因子),随着QPSK和16QAM调制的频域扩频因子增加,所需的每符号与背景噪声功率谱密度比(E/sub s//N/sub 0/)的平均接收信号能量降低(注意,尽管如此,在这种较轻的信道负载条件下,用QPSK调制代替16QAm调制,同时信道负载是16QAm的两倍,以实现相同的信息比特率)。同时,当信道负载接近满时,如C/sub mux//SF = 0.94时,根据延迟扩展,16QAM调制的频域最佳扩展因子为SF/sub Freq/ = 1, QPSK调制的频域最佳扩展因子为SF/sub Freq/ = 1 ~ 8。因此,通过在时域和频域中设置几种扩展因子的组合,在假定各种信道条件的蜂窝和热点蜂窝配置中都可以实现接近最大的链路容量。
{"title":"Variable spreading factor-OFCDM with two dimensional spreading that prioritizes time domain spreading for forward link broadband wireless access","authors":"N. Maeda, Y. Kishiyama, H. Atarashi, M. Sawahashi","doi":"10.1109/VETECS.2003.1207516","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207516","url":null,"abstract":"This paper proposes the optimum design for adaptively controlling the spreading factor in orthogonal frequency and code division multiplexing (OFCDM) with two-dimensional spreading according to the cell configuration, channel load, and propagation channel conditions, assuming the adaptive modulation and channel coding (AMC) scheme employing QPSK and 16QAM data modulation. Furthermore, we propose a two-dimensional channelization code assignment scheme to achieve skillfully orthogonal multiplexing of multiple physical channels. Computer simulation results elucidate that bit-interleaving in the frequency domain is superior to chip-interleaving especially for a full channel load because bit-interleaving exhibits a large randomization effect of burst errors, while still maintaining code orthogonality. In time domain spreading, the optimum spreading factor, except for an extremely high mobility case such as for the fading maximum Doppler frequency f/sub D/ = 1500 Hz, becomes SF/sub Time/ = 16, and it should be decreased to SF/sub Time/ = 8 for such a very fast fading environment using 16QAM modulation. When the channel load is light such as C/sub mux//SF = 0.25 (C/sub mux/ and SF denote the number of multiplexed codes and total spreading factor, respectively), the required average received signal energy per symbol-to-background noise power spectrum density ratio (E/sub s//N/sub 0/) is reduced as the spreading factor in the frequency domain is increased up to say SF/sub Freq/ = 32 for QPSK and 16QAM modulation, respectively (Note that, nevertheless, 16QAm modulation under such a lighter channel load condition is replaced by QPSK modulation together with two fold the channel load as 16QAM to achieve the same information bit rate). Meanwhile, when the channel load is close to full such as when C/sub mux//SF = 0.94, the optimum spreading factor in the frequency domain is SF/sub Freq/ = 1 for 16QAM modulation and SF/sub Freq/ = 1 to 8 for QPSK modulation according to the delay spread. Consequently, by setting several combinations of spreading factors in the time and frequency domains, the near maximum link capacity is achieved both in cellular and hot-spot cell configurations assuming various channel conditions.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115439742","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: 85
Uplink and downlink SIR analysis for base station placement 基站布置上行和下行SIR分析
Pub Date : 2003-04-22 DOI: 10.1109/VETECS.2003.1207513
Joseph K. L. Wong, M. Neve, K. Sowerby
Most published work relating to base station placement focuses on desired signal coverage in outdoor wireless systems. However, this approach may not be adequate for future indoor wireless CDMA systems since the systems are interference-limited. In this paper, we present a method for solving the base station placement problem using binary integer programming (BIP). This formulation incorporates coverage, transmitter power and both the uplink and downlink signal-to-interference-ratios into the optimisation process. It is shown that both the uplink and downlink signal-to-interference-ratios should be considered when planning indoor wireless CDMA systems.
大多数已发表的有关基站放置的工作集中在室外无线系统中所需的信号覆盖。然而,这种方法可能不适合未来的室内无线CDMA系统,因为系统是受干扰限制的。本文提出了一种用二进制整数规划(BIP)求解基站布局问题的方法。该配方将覆盖范围、发射机功率以及上行链路和下行链路的信号干扰比纳入优化过程。研究表明,在规划室内无线CDMA系统时,应同时考虑上行链路和下行链路的信干扰比。
{"title":"Uplink and downlink SIR analysis for base station placement","authors":"Joseph K. L. Wong, M. Neve, K. Sowerby","doi":"10.1109/VETECS.2003.1207513","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207513","url":null,"abstract":"Most published work relating to base station placement focuses on desired signal coverage in outdoor wireless systems. However, this approach may not be adequate for future indoor wireless CDMA systems since the systems are interference-limited. In this paper, we present a method for solving the base station placement problem using binary integer programming (BIP). This formulation incorporates coverage, transmitter power and both the uplink and downlink signal-to-interference-ratios into the optimisation process. It is shown that both the uplink and downlink signal-to-interference-ratios should be considered when planning indoor wireless CDMA systems.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115639856","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
Design alternatives for IP in vehicles 车辆IP的设计方案
Pub Date : 2003-04-22 DOI: 10.1109/VETECS.2003.1207130
C. Maihofer, M. Bechler
For most network technologies, researchers and engineers already have developed mechanisms to run IP on top of the natively supported protocols. Such network technologies include for example IEEE 802, IEEE 1394 networks, or Bluetooth. In the automotive domain other network technologies like CAN and MOST are in use and new ad hoc networks for car-to-car communication are currently being developed. This paper presents and discusses generic approaches for implementing IP in intra-vehicular networks. The discussion includes the criteria whether standard software can be used or customized software has to be developed, the resulting efficiency regarding the message overhead, the fault tolerance of an approach and finally their efficient support for mobile nodes.
对于大多数网络技术,研究人员和工程师已经开发出在本地支持的协议之上运行IP的机制。这种网络技术包括例如IEEE 802、IEEE 1394网络或蓝牙。在汽车领域,诸如CAN和MOST等其他网络技术正在使用,目前正在开发用于车对车通信的新型自组织网络。本文提出并讨论了在车内网络中实现IP的一般方法。讨论了是否可以使用标准软件或必须开发定制软件的标准,关于消息开销的效率,方法的容错能力以及它们对移动节点的有效支持。
{"title":"Design alternatives for IP in vehicles","authors":"C. Maihofer, M. Bechler","doi":"10.1109/VETECS.2003.1207130","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207130","url":null,"abstract":"For most network technologies, researchers and engineers already have developed mechanisms to run IP on top of the natively supported protocols. Such network technologies include for example IEEE 802, IEEE 1394 networks, or Bluetooth. In the automotive domain other network technologies like CAN and MOST are in use and new ad hoc networks for car-to-car communication are currently being developed. This paper presents and discusses generic approaches for implementing IP in intra-vehicular networks. The discussion includes the criteria whether standard software can be used or customized software has to be developed, the resulting efficiency regarding the message overhead, the fault tolerance of an approach and finally their efficient support for mobile nodes.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124173682","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: 6
Simple iterative chip-by-chip multiuser detection for CDMA systems CDMA系统的简单迭代逐片多用户检测
Pub Date : 2003-04-22 DOI: 10.1109/VETECS.2003.1207209
Lihai Liu, W. K. Leung, L. Ping
This paper examines several low-cost iterative chip-by-chip multiuser detection algorithms for chip-interleaved code-division multiple-access (CDMA) systems in multipath and multiple antenna environments. The complexities (per user) of these algorithms are very low and increase either linearly or quadratically with path number. It is shown that a system employing a rate-1/2 16-state convolutional code and a length-8 spreading sequence can support more than 100 users with two receive antennas.
本文研究了在多路径和多天线环境下用于片间交错码分多址(CDMA)系统的几种低成本迭代片间多用户检测算法。这些算法的复杂性(每个用户)非常低,并且随着路径数线性或二次增长。结果表明,采用速率为1/2的16态卷积码和长度为8的扩展序列的系统可以支持100个以上的用户和两个接收天线。
{"title":"Simple iterative chip-by-chip multiuser detection for CDMA systems","authors":"Lihai Liu, W. K. Leung, L. Ping","doi":"10.1109/VETECS.2003.1207209","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207209","url":null,"abstract":"This paper examines several low-cost iterative chip-by-chip multiuser detection algorithms for chip-interleaved code-division multiple-access (CDMA) systems in multipath and multiple antenna environments. The complexities (per user) of these algorithms are very low and increase either linearly or quadratically with path number. It is shown that a system employing a rate-1/2 16-state convolutional code and a length-8 spreading sequence can support more than 100 users with two receive antennas.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"292 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124203656","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: 103
期刊
The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1