Pub Date : 2002-08-07DOI: 10.1109/VTC.2002.1002700
H. Nie, P. Mathiopoulos
We propose a software radio based distributed base station (DBS) architecture which replaces conventional base stations with a cluster of DBS and a central processing station (CPS) which are connected by a high speed data communication network. As most signal processing is carried out in the CPS, the DBS is compact and lightweight, and requires low power for operation, so it can be deployed economically and virtually everywhere. Furthermore, since the radio signals received by different DBS are processed in one CPS, signal combining techniques (SCT) can be employed to improve the reverse link capacity of the 3G UMTS. Analytical expressions for this improvement are derived using the concept of percentage of coverage area with and without the SCT. Complementary computer simulation results for a cdma2000 system have also shown that by employing the SCT, the proposed software radio based DBS architecture can achieve significant reverse link capacity improvement.
{"title":"A new software radio based distributed base station architecture and its application to 3G UMTS employing signal combining techniques","authors":"H. Nie, P. Mathiopoulos","doi":"10.1109/VTC.2002.1002700","DOIUrl":"https://doi.org/10.1109/VTC.2002.1002700","url":null,"abstract":"We propose a software radio based distributed base station (DBS) architecture which replaces conventional base stations with a cluster of DBS and a central processing station (CPS) which are connected by a high speed data communication network. As most signal processing is carried out in the CPS, the DBS is compact and lightweight, and requires low power for operation, so it can be deployed economically and virtually everywhere. Furthermore, since the radio signals received by different DBS are processed in one CPS, signal combining techniques (SCT) can be employed to improve the reverse link capacity of the 3G UMTS. Analytical expressions for this improvement are derived using the concept of percentage of coverage area with and without the SCT. Complementary computer simulation results for a cdma2000 system have also shown that by employing the SCT, the proposed software radio based DBS architecture can achieve significant reverse link capacity improvement.","PeriodicalId":159750,"journal":{"name":"Vehicular Technology Conference. IEEE 55th Vehicular Technology Conference. VTC Spring 2002 (Cat. No.02CH37367)","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122095451","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 : 2002-08-07DOI: 10.1109/VTC.2002.1002786
Woo-Jin Choi, S. Tekinay
Location tracking in wireless networks is essential for ubiquitous communication service. Since a user may move freely, the network has to keep track of the location of the mobile terminal to deliver messages or calls. There has been significant effort to address the problem of user mobility; however, most of the mobility models introduced in the previous work do not take the movement direction into account - the parameter called CMR (call to mobility ratio) which is commonly used in the literature is the ratio between the call arrival rate and the cell boundary crossing rate of the mobile. In this paper, we introduce Brownian motion with drift as our mobility model and discuss the effect of movement direction and call arrivals on the performance of the distance-based location update scheme in the predictive and the non predictive mode.
无线网络中的位置跟踪是实现无处不在通信服务的必要条件。由于用户可以自由移动，因此网络必须跟踪移动终端的位置以发送消息或呼叫。在解决用户移动性问题方面已经做出了重大努力;然而，在之前的工作中引入的大多数迁移模型都没有考虑到移动方向——文献中常用的CMR (call to mobility ratio)参数是呼叫到达率与移动设备的小区边界穿越率之间的比率。本文引入带漂移的布朗运动作为移动模型，讨论了移动方向和呼叫到达对基于距离的位置更新方案在预测和非预测模式下性能的影响。
{"title":"Distance-based location update scheme with isotropic random user motion with drift","authors":"Woo-Jin Choi, S. Tekinay","doi":"10.1109/VTC.2002.1002786","DOIUrl":"https://doi.org/10.1109/VTC.2002.1002786","url":null,"abstract":"Location tracking in wireless networks is essential for ubiquitous communication service. Since a user may move freely, the network has to keep track of the location of the mobile terminal to deliver messages or calls. There has been significant effort to address the problem of user mobility; however, most of the mobility models introduced in the previous work do not take the movement direction into account - the parameter called CMR (call to mobility ratio) which is commonly used in the literature is the ratio between the call arrival rate and the cell boundary crossing rate of the mobile. In this paper, we introduce Brownian motion with drift as our mobility model and discuss the effect of movement direction and call arrivals on the performance of the distance-based location update scheme in the predictive and the non predictive mode.","PeriodicalId":159750,"journal":{"name":"Vehicular Technology Conference. IEEE 55th Vehicular Technology Conference. VTC Spring 2002 (Cat. No.02CH37367)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117333679","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 : 2002-08-07DOI: 10.1109/VTC.2002.1002937
M. Benson, H. Thomas
UMTS is a third generation (3G) mobile communications system, currently being standardized and developed by many mobile technology manufacturers and operators. Unlike the second generation systems such as GSM, which provide voice and low speed data services, 3G promises to provide high speed data as well as multiple-data rate services, which is opening doors to many exciting multimedia applications. The initial deployment of UMTS is expected to be in cities, providing islands of coverage. Therefore, effective handover from UMTS to GSM is imperative for mobiles when they roam out of UMTS coverage. The paper presents the results of system simulations which provide some insights into the conditions and parameters involved in inter-system handover from UMTS-FDD to GSM.
{"title":"Investigation of the UMTS to GSM handover procedure","authors":"M. Benson, H. Thomas","doi":"10.1109/VTC.2002.1002937","DOIUrl":"https://doi.org/10.1109/VTC.2002.1002937","url":null,"abstract":"UMTS is a third generation (3G) mobile communications system, currently being standardized and developed by many mobile technology manufacturers and operators. Unlike the second generation systems such as GSM, which provide voice and low speed data services, 3G promises to provide high speed data as well as multiple-data rate services, which is opening doors to many exciting multimedia applications. The initial deployment of UMTS is expected to be in cities, providing islands of coverage. Therefore, effective handover from UMTS to GSM is imperative for mobiles when they roam out of UMTS coverage. The paper presents the results of system simulations which provide some insights into the conditions and parameters involved in inter-system handover from UMTS-FDD to GSM.","PeriodicalId":159750,"journal":{"name":"Vehicular Technology Conference. IEEE 55th Vehicular Technology Conference. VTC Spring 2002 (Cat. No.02CH37367)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129760479","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 : 2002-08-07DOI: 10.1109/VTC.2002.1002732
D. Browne, J. Medbø, H. Asplund, J. Berg
The approach presented herein provides a simple and accurate propagation model for indoor environments. The model is able to generate point sources with joint angle-delay-power characteristics that are sensitive to the macrostructure of the site's floorplan geometry. This is achieved in two stages. First, the floorplan geometry is reduced to an essential set of features using an automated routine based on computational geometry. Then an algorithmic set of propagation rules founded on finite difference time domain and ray tracing simulations are applied to the reduced geometry to reconstruct propagation paths. Simulation results are presented and compared with recent data from a measurement campaign for the same scenario. The model is seen to accurately capture the macrostructure characteristics of the channel including angle spread, delay spread, temporal clustering, angular clustering, and power profile.
{"title":"A simple approach to site sensitive modeling of indoor radio propagation","authors":"D. Browne, J. Medbø, H. Asplund, J. Berg","doi":"10.1109/VTC.2002.1002732","DOIUrl":"https://doi.org/10.1109/VTC.2002.1002732","url":null,"abstract":"The approach presented herein provides a simple and accurate propagation model for indoor environments. The model is able to generate point sources with joint angle-delay-power characteristics that are sensitive to the macrostructure of the site's floorplan geometry. This is achieved in two stages. First, the floorplan geometry is reduced to an essential set of features using an automated routine based on computational geometry. Then an algorithmic set of propagation rules founded on finite difference time domain and ray tracing simulations are applied to the reduced geometry to reconstruct propagation paths. Simulation results are presented and compared with recent data from a measurement campaign for the same scenario. The model is seen to accurately capture the macrostructure characteristics of the channel including angle spread, delay spread, temporal clustering, angular clustering, and power profile.","PeriodicalId":159750,"journal":{"name":"Vehicular Technology Conference. IEEE 55th Vehicular Technology Conference. VTC Spring 2002 (Cat. No.02CH37367)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129858848","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 : 2002-08-07DOI: 10.1109/VTC.2002.1002645
Junghoon Suh, M. Howlader
Higher transmission rate and reliable communication over fading channels are major research pursuits of current wireless communications. The space-time block codes (STBC) have been introduced to improve those research goals by simple processing algorithms at the transmitter and the receiver ends. STBC designs with the help of an orthogonal design method are described. The STBC designed in a quasi-orthogonal method is focused on keeping the higher transmission rate at the cost of the diversity gain. On the other hand, STBC designed in complex orthogonal methods emphasize the high diversity gain rather than the rate. Design schemes of turbo concatenation to STBC using various methods are introduced and detailed performance analyses are provided.
{"title":"Design schemes of space-time block codes concatenated with turbo codes","authors":"Junghoon Suh, M. Howlader","doi":"10.1109/VTC.2002.1002645","DOIUrl":"https://doi.org/10.1109/VTC.2002.1002645","url":null,"abstract":"Higher transmission rate and reliable communication over fading channels are major research pursuits of current wireless communications. The space-time block codes (STBC) have been introduced to improve those research goals by simple processing algorithms at the transmitter and the receiver ends. STBC designs with the help of an orthogonal design method are described. The STBC designed in a quasi-orthogonal method is focused on keeping the higher transmission rate at the cost of the diversity gain. On the other hand, STBC designed in complex orthogonal methods emphasize the high diversity gain rather than the rate. Design schemes of turbo concatenation to STBC using various methods are introduced and detailed performance analyses are provided.","PeriodicalId":159750,"journal":{"name":"Vehicular Technology Conference. IEEE 55th Vehicular Technology Conference. VTC Spring 2002 (Cat. No.02CH37367)","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128348700","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 : 2002-08-07DOI: 10.1109/VTC.2002.1002647
N. Chen, R. Heaton, Miyuki Tanaka
Channel impairments, such as multipath reflections, can have a profound impact on the bit error rate achievable in OFDM transmission applications. This paper presents a new channel equalisation technique that uses scattered pilots in OFDM symbols to estimate the delay parameters associated with a two-path model as an approximation of a multipath channel. It is applicable for both fixed and mobile reception. Results from simulation studies under multipath Rayleigh channel have shown that the algorithm can offer a substantial performance improvement over that obtained with a conventional linear interpolation approach, used as a benchmark. This is also confirmed by applying the algorithm to data recorded by an OFDM receiver in practical experiments that involved reception of five transmissions of OFDM symbols both 'off air' and through a channel simulator.
{"title":"Channel equalisation for OFDM using scattered pilots","authors":"N. Chen, R. Heaton, Miyuki Tanaka","doi":"10.1109/VTC.2002.1002647","DOIUrl":"https://doi.org/10.1109/VTC.2002.1002647","url":null,"abstract":"Channel impairments, such as multipath reflections, can have a profound impact on the bit error rate achievable in OFDM transmission applications. This paper presents a new channel equalisation technique that uses scattered pilots in OFDM symbols to estimate the delay parameters associated with a two-path model as an approximation of a multipath channel. It is applicable for both fixed and mobile reception. Results from simulation studies under multipath Rayleigh channel have shown that the algorithm can offer a substantial performance improvement over that obtained with a conventional linear interpolation approach, used as a benchmark. This is also confirmed by applying the algorithm to data recorded by an OFDM receiver in practical experiments that involved reception of five transmissions of OFDM symbols both 'off air' and through a channel simulator.","PeriodicalId":159750,"journal":{"name":"Vehicular Technology Conference. IEEE 55th Vehicular Technology Conference. VTC Spring 2002 (Cat. No.02CH37367)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129736476","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 : 2002-08-07DOI: 10.1109/VTC.2002.1002588
M. Kuhn, A. Wittneben
Decision feedback equalization (DFE) and antenna diversity combining are two practical and well-known techniques for combating multipath ISI due to frequency-selective fading. We propose a scalable very low complexity combination of antenna combining and decision feedback equalization, which considers the characteristics of mobile communication channels. The performance of this new equalization method is compared to state-of-the-art equalizers by means of simulations. The complexity is evaluated by estimating the total computing expenditure. In addition a very efficient low-cost hardware structure for implementation is proposed. The algorithms are adapted for this hardware structure and the performance of this optimization is illustrated by simulation results.
{"title":"Very low complexity space-time decision feedback equalization of intersymbol interference on severe frequency-selective fading channels","authors":"M. Kuhn, A. Wittneben","doi":"10.1109/VTC.2002.1002588","DOIUrl":"https://doi.org/10.1109/VTC.2002.1002588","url":null,"abstract":"Decision feedback equalization (DFE) and antenna diversity combining are two practical and well-known techniques for combating multipath ISI due to frequency-selective fading. We propose a scalable very low complexity combination of antenna combining and decision feedback equalization, which considers the characteristics of mobile communication channels. The performance of this new equalization method is compared to state-of-the-art equalizers by means of simulations. The complexity is evaluated by estimating the total computing expenditure. In addition a very efficient low-cost hardware structure for implementation is proposed. The algorithms are adapted for this hardware structure and the performance of this optimization is illustrated by simulation results.","PeriodicalId":159750,"journal":{"name":"Vehicular Technology Conference. IEEE 55th Vehicular Technology Conference. VTC Spring 2002 (Cat. No.02CH37367)","volume":"129 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124239797","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 : 2002-08-07DOI: 10.1109/VTC.2002.1002797
Jeong-woo Cho, T. Kwon, Changhoi Koo, D. Park, Daegyun Kim, D. Cho
One of main issues in 1/spl times/EV-DV systems is how to support and satisfy various QoS requirements of data services and voice service simultaneously. Another main issue in 1/spl times/EV-DV systems is how to increase throughput of data services without sacrificing voice service QoS requirements. The main motivation for our proposed architecture, MQC (multiple quality control), is to use per-stream buffers in the physical layer and to fully utilize air resources. The problem of existing architectures is that PDUs from only one stream can be transmitted and those PDUs may not fill out the allocated time slots. In contrast to existing architectures, MQC can multiplex several streams into one PLP (physical layer packet) because MQC utilizes per-service buffers in the physical layer. We also introduce a multiplexing scheme that minimizes queueing delays of real-time traffic and maximizes cell throughputs.
{"title":"Multiple quality control: a new framework for QoS control in forward link of 1/spl times/EV-DV systems","authors":"Jeong-woo Cho, T. Kwon, Changhoi Koo, D. Park, Daegyun Kim, D. Cho","doi":"10.1109/VTC.2002.1002797","DOIUrl":"https://doi.org/10.1109/VTC.2002.1002797","url":null,"abstract":"One of main issues in 1/spl times/EV-DV systems is how to support and satisfy various QoS requirements of data services and voice service simultaneously. Another main issue in 1/spl times/EV-DV systems is how to increase throughput of data services without sacrificing voice service QoS requirements. The main motivation for our proposed architecture, MQC (multiple quality control), is to use per-stream buffers in the physical layer and to fully utilize air resources. The problem of existing architectures is that PDUs from only one stream can be transmitted and those PDUs may not fill out the allocated time slots. In contrast to existing architectures, MQC can multiplex several streams into one PLP (physical layer packet) because MQC utilizes per-service buffers in the physical layer. We also introduce a multiplexing scheme that minimizes queueing delays of real-time traffic and maximizes cell throughputs.","PeriodicalId":159750,"journal":{"name":"Vehicular Technology Conference. IEEE 55th Vehicular Technology Conference. VTC Spring 2002 (Cat. No.02CH37367)","volume":"72 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123524745","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 : 2002-08-07DOI: 10.1109/VTC.2002.1002878
Zongwang Li, L. Zeng, Wentao Song, Youyun Xu, Han-wen Luo
We propose a novel iterative decoding algorithm based on partial combination of the parity check matrix for iterative soft decoding of Reed-Solomon product codes. It uses only the simple syndrome equations whose solutions are confined to parts of the columns of the parity check matrix. Compared to other algorithms, the proposed algorithm has lower complexity while offering better performance, which is demonstrated by simulations.
{"title":"A simple iterative soft decoding algorithm for Reed-Solomon product codes","authors":"Zongwang Li, L. Zeng, Wentao Song, Youyun Xu, Han-wen Luo","doi":"10.1109/VTC.2002.1002878","DOIUrl":"https://doi.org/10.1109/VTC.2002.1002878","url":null,"abstract":"We propose a novel iterative decoding algorithm based on partial combination of the parity check matrix for iterative soft decoding of Reed-Solomon product codes. It uses only the simple syndrome equations whose solutions are confined to parts of the columns of the parity check matrix. Compared to other algorithms, the proposed algorithm has lower complexity while offering better performance, which is demonstrated by simulations.","PeriodicalId":159750,"journal":{"name":"Vehicular Technology Conference. IEEE 55th Vehicular Technology Conference. VTC Spring 2002 (Cat. No.02CH37367)","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123630989","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 : 2002-08-07DOI: 10.1109/VTC.2002.1002969
Lichung Chu, Russel Fagg, T. Klingenbrunn, Lind Mortensen, B. Vejlgaard
When GSM at 850 MHz is deployed in the USA, it will have to coexist in the cellular band with AMPS. Previous studies have examined the coexistence of multiple standards in the US PCS band (see TR46 Telecommunications System Bulletin TSB-84A, 2001), but have not examined the coexistence between AMPS and GSM. This analysis focuses on the impact that coexistence has on radio receiver blocking and the second and third order intermodulation requirements. The paper concludes with an estimate of the outage probability in the GSM cell due to coexistence with AMPS. GSM and AMPS base station colocation and its impact on outage probability is also considered.
{"title":"GSM and AMPS coexistence in the US cellular band","authors":"Lichung Chu, Russel Fagg, T. Klingenbrunn, Lind Mortensen, B. Vejlgaard","doi":"10.1109/VTC.2002.1002969","DOIUrl":"https://doi.org/10.1109/VTC.2002.1002969","url":null,"abstract":"When GSM at 850 MHz is deployed in the USA, it will have to coexist in the cellular band with AMPS. Previous studies have examined the coexistence of multiple standards in the US PCS band (see TR46 Telecommunications System Bulletin TSB-84A, 2001), but have not examined the coexistence between AMPS and GSM. This analysis focuses on the impact that coexistence has on radio receiver blocking and the second and third order intermodulation requirements. The paper concludes with an estimate of the outage probability in the GSM cell due to coexistence with AMPS. GSM and AMPS base station colocation and its impact on outage probability is also considered.","PeriodicalId":159750,"journal":{"name":"Vehicular Technology Conference. IEEE 55th Vehicular Technology Conference. VTC Spring 2002 (Cat. No.02CH37367)","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114318370","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}
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