Pub Date : 2007-12-04DOI: 10.1109/ISCIT.2007.4392104
Yachen Wang, G. Xie, Yuan'an Liu, Na Li
This paper puts forward two novel user-grouping algorithms for grouped MC-CDMA systems. The adaptive assignment for user-grouping plays an important role for link quality. We formulate the capacity-maximizing problem of user-grouping and analysis the optimal criterion for it. The derived optimal criterion has a similar form with signal to noise plus interference (SINR), with unassigned power included. Thus the unassigned power leads to an unpractical usage. We then investigate user's equivalent SINR for minimum mean square error (MMSE) detection serving as assignment criterion, and propose two kinds of user-grouping algorithms. In these algorithms, only partial channel information is needed at the base station, which saves a large part of bandwidth occupying by feedback information. The proposed algorithms are evaluated by computer simulations to be prior to the conventional algorithm at both BER performance and data rate. Meanwhile, they have a lower implementation complexity for practical reality.
{"title":"Feasible resource allocation with partial channel information for grouped MC-CDMA systems","authors":"Yachen Wang, G. Xie, Yuan'an Liu, Na Li","doi":"10.1109/ISCIT.2007.4392104","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392104","url":null,"abstract":"This paper puts forward two novel user-grouping algorithms for grouped MC-CDMA systems. The adaptive assignment for user-grouping plays an important role for link quality. We formulate the capacity-maximizing problem of user-grouping and analysis the optimal criterion for it. The derived optimal criterion has a similar form with signal to noise plus interference (SINR), with unassigned power included. Thus the unassigned power leads to an unpractical usage. We then investigate user's equivalent SINR for minimum mean square error (MMSE) detection serving as assignment criterion, and propose two kinds of user-grouping algorithms. In these algorithms, only partial channel information is needed at the base station, which saves a large part of bandwidth occupying by feedback information. The proposed algorithms are evaluated by computer simulations to be prior to the conventional algorithm at both BER performance and data rate. Meanwhile, they have a lower implementation complexity for practical reality.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"203 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122415188","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392194
P. Silva, R. Dinis
In this paper we consider the uplink transmission in MC-CDMA (multicarrier -coded division multiple access) systems. Since MC-CDMA signals are OFDM-like multicarrier signals, they have high envelope fluctuations and a high PMEPR (Peak-to-Mean Envelope Power Ratio) which leads to amplification difficulties. To reduce the envelope fluctuations of the transmitted signals, while maintaining the spectral efficiency, the MC-CDMA signal associated to each MT (mobile terminal) is submitted to a clipping device, followed by a frequency-domain filtering operation. However, the nonlinear distortion effects can be high when an MC-CDMA transmitter with reduced envelope fluctuations is intended. In this paper, we define an iterative receiver that jointly performs a turbo-MUD (Multiuser Detection) and the estimation and cancellation of the nonlinear distortion effects. The set of simulation results presented shows that the proposed receiver structure allows good performances, very close to the linear receiver ones, even for high system load and/or when a low-PMEPR is intended for each MT.
{"title":"Turbo multiuser detection for MC-CDMA signals with strongly nonlinear transmitters","authors":"P. Silva, R. Dinis","doi":"10.1109/ISCIT.2007.4392194","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392194","url":null,"abstract":"In this paper we consider the uplink transmission in MC-CDMA (multicarrier -coded division multiple access) systems. Since MC-CDMA signals are OFDM-like multicarrier signals, they have high envelope fluctuations and a high PMEPR (Peak-to-Mean Envelope Power Ratio) which leads to amplification difficulties. To reduce the envelope fluctuations of the transmitted signals, while maintaining the spectral efficiency, the MC-CDMA signal associated to each MT (mobile terminal) is submitted to a clipping device, followed by a frequency-domain filtering operation. However, the nonlinear distortion effects can be high when an MC-CDMA transmitter with reduced envelope fluctuations is intended. In this paper, we define an iterative receiver that jointly performs a turbo-MUD (Multiuser Detection) and the estimation and cancellation of the nonlinear distortion effects. The set of simulation results presented shows that the proposed receiver structure allows good performances, very close to the linear receiver ones, even for high system load and/or when a low-PMEPR is intended for each MT.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122598706","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392018
T. Sato, S. Mizushima, S. Imai, Y. Suzuki, S. Murata
In this paper, a synchronous high-speed logic standard cells using bootstrapped technology for low temperature poly silicon thin film transistor -liquid crystal display (LTPS TFT-LCD) panel is proposed. The proposed TFT standard cells operate at high frequency region owing to the deep non-saturation operation by using the bootstrapped technology (BST). The proposed TFT standard cells can be reduced the pattern size by using the TFT capacitors for the bootstrapped capacitors. To confirm some characteristics of the proposed TFT standard cells, a full adder (FA) are simulated. As a result, the power delay products obtain about 1/5-9/10 times less value than that of the conventional standard cells using LTPS TFT.
{"title":"High speed standard cell using bootstrapped technology for LTPSTFT","authors":"T. Sato, S. Mizushima, S. Imai, Y. Suzuki, S. Murata","doi":"10.1109/ISCIT.2007.4392018","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392018","url":null,"abstract":"In this paper, a synchronous high-speed logic standard cells using bootstrapped technology for low temperature poly silicon thin film transistor -liquid crystal display (LTPS TFT-LCD) panel is proposed. The proposed TFT standard cells operate at high frequency region owing to the deep non-saturation operation by using the bootstrapped technology (BST). The proposed TFT standard cells can be reduced the pattern size by using the TFT capacitors for the bootstrapped capacitors. To confirm some characteristics of the proposed TFT standard cells, a full adder (FA) are simulated. As a result, the power delay products obtain about 1/5-9/10 times less value than that of the conventional standard cells using LTPS TFT.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127618869","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392149
K. Asakura, H. Sanada, O. Ogurisu, M. Suzuki
In this paper, we propose a practical band estimation method for periodic superlattices by using semi-infinite periodic model, which is located in the middle of finite periodic model and infinite periodic model. According to the model proposed, we can estimate not only band structures but also ripples in passbands for periodic superlattices with simple calculation by applying image parameters in circuit theory. This model may be useful for energy filter designing, since the ripples in passbands are the essential information related with energy filter abilities.
{"title":"Practical band estimation for periodic superlattices by using semi-infinite periodic model","authors":"K. Asakura, H. Sanada, O. Ogurisu, M. Suzuki","doi":"10.1109/ISCIT.2007.4392149","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392149","url":null,"abstract":"In this paper, we propose a practical band estimation method for periodic superlattices by using semi-infinite periodic model, which is located in the middle of finite periodic model and infinite periodic model. According to the model proposed, we can estimate not only band structures but also ripples in passbands for periodic superlattices with simple calculation by applying image parameters in circuit theory. This model may be useful for energy filter designing, since the ripples in passbands are the essential information related with energy filter abilities.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"173 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133306942","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392017
Yong Sun, F. Lai
Two topologies of SI comparator for low power current mode circuit implementation are presented. Employing different input stages, these two comparators are suitable to different application cases. Controlled by two complementary clock signals, the proposed comparator operates in a master and slave manner. Sharing a 0-static-power-dissipated dynamic latched comparator as the output comparators, both high power efficiency and high speed are acquired for these two comparators. Designed and simulated in TSMC 0.18 mum mixed signal CMOS technology with 1.8 V supply voltage, the proposed SI comparators achieve a current sensitivity up to 0.2 muA, and a sampling frequency up to 1 GHz, with 8.6 bits resolutions.
{"title":"Low power high speed switched current comparators for current mode ADC","authors":"Yong Sun, F. Lai","doi":"10.1109/ISCIT.2007.4392017","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392017","url":null,"abstract":"Two topologies of SI comparator for low power current mode circuit implementation are presented. Employing different input stages, these two comparators are suitable to different application cases. Controlled by two complementary clock signals, the proposed comparator operates in a master and slave manner. Sharing a 0-static-power-dissipated dynamic latched comparator as the output comparators, both high power efficiency and high speed are acquired for these two comparators. Designed and simulated in TSMC 0.18 mum mixed signal CMOS technology with 1.8 V supply voltage, the proposed SI comparators achieve a current sensitivity up to 0.2 muA, and a sampling frequency up to 1 GHz, with 8.6 bits resolutions.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133365877","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392096
Lu Li-hua, Ma Xiao-lei, Li Yuan-An
NEMO basic support protocol enables mobile networks preserve communication with other nodes, while changing their point of attachment to the Internet. But in nested mobile network, Pinball routing problem appears. In this paper, a route optimization solution for mobile networks based on local mobility management framework was proposed to improve the performance. By defining the operation on local mobility anchor, forward routing path, reverse routing path and routing inside local mobility domain will be optimized. The tunnel path will be reduced, and performance will be improved. Analytical and simulation results demonstrate that our solution is a viable scheme to optimize route for nested-NEMO.
{"title":"Route optimization solution for nested mobile network in local mobility domain with multiple local mobility anchors","authors":"Lu Li-hua, Ma Xiao-lei, Li Yuan-An","doi":"10.1109/ISCIT.2007.4392096","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392096","url":null,"abstract":"NEMO basic support protocol enables mobile networks preserve communication with other nodes, while changing their point of attachment to the Internet. But in nested mobile network, Pinball routing problem appears. In this paper, a route optimization solution for mobile networks based on local mobility management framework was proposed to improve the performance. By defining the operation on local mobility anchor, forward routing path, reverse routing path and routing inside local mobility domain will be optimized. The tunnel path will be reduced, and performance will be improved. Analytical and simulation results demonstrate that our solution is a viable scheme to optimize route for nested-NEMO.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124405649","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392135
J.C.-P. Wang, M. Abolhasan, F. Safaei, D. Franklin
The rapid diminishing in the cost of commodity wireless hardware in recent years has prompted the use of multiple radios to improve the capacity of wireless networks. However, the research has shown that the improvement obtained from using multiple radios does not solely depend on the number of radios, but primarily on how these radios can be integrated in a constructive manner. A common way of integration multiple radios is to use a dedicated radio for control. To date, a number of multi-radio MAC protocol are employing a dedicated radio to control and coordinate the other radios, though the approaches are varied from one to another. In this paper, the control separation techniques in the multi-radio multi-channel MAC have been surveyed, and a classification of control separation techniques is provided. Moreover, this study points out the open research issues and intends to spark new interests and developments in this field.
{"title":"A survey on control separation techniques in multi-radio multi-channel MAC protocols","authors":"J.C.-P. Wang, M. Abolhasan, F. Safaei, D. Franklin","doi":"10.1109/ISCIT.2007.4392135","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392135","url":null,"abstract":"The rapid diminishing in the cost of commodity wireless hardware in recent years has prompted the use of multiple radios to improve the capacity of wireless networks. However, the research has shown that the improvement obtained from using multiple radios does not solely depend on the number of radios, but primarily on how these radios can be integrated in a constructive manner. A common way of integration multiple radios is to use a dedicated radio for control. To date, a number of multi-radio MAC protocol are employing a dedicated radio to control and coordinate the other radios, though the approaches are varied from one to another. In this paper, the control separation techniques in the multi-radio multi-channel MAC have been surveyed, and a classification of control separation techniques is provided. Moreover, this study points out the open research issues and intends to spark new interests and developments in this field.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122158580","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392208
R. Chrabieh, S. Soliman
WiMedia UWB is a high data rate OFDM system for wireless personal area networks. The design philosophy is a mixture of high throughput and low power consumption. The standard uses special time and frequency domain spreading to enable low power consumption for the low data rates and for low-end devices. A loss of channel diversity is observed in certain scenarios. First we describe an efficient frequency domain spreading implementation in time domain. Then using this key idea, we propose new spreading schemes, either to recover the diversity loss or to achieve additional power and hardware savings for low-end devices.
{"title":"Enhanced frequency domain spreading for WiMedia UWB","authors":"R. Chrabieh, S. Soliman","doi":"10.1109/ISCIT.2007.4392208","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392208","url":null,"abstract":"WiMedia UWB is a high data rate OFDM system for wireless personal area networks. The design philosophy is a mixture of high throughput and low power consumption. The standard uses special time and frequency domain spreading to enable low power consumption for the low data rates and for low-end devices. A loss of channel diversity is observed in certain scenarios. First we describe an efficient frequency domain spreading implementation in time domain. Then using this key idea, we propose new spreading schemes, either to recover the diversity loss or to achieve additional power and hardware savings for low-end devices.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134229552","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392130
A. Allwright, Dennis Perisa, P. Pourbeik
There have been many studies in recent years reporting the performance and survivability of mobile ad-hoc networks (MANETs). These studies invariably consider the network as covering a relatively small geographic area. However, in many crises, such as may occur during disaster relief and military operations, a wide geographic area may require network coverage. In these circumstances, the infrastructure free mobile wireless communications features of MANETs may be critical in forming a satisfactory network. Given transmission range limitations within current MANET proposals, it is likely that providing network coverage to a wide geographic area would be problematic. This paper presents the results of a study on clustering in the spatial distribution of communication nodes. A realistic environment (e.g. topography and organisational limitations) and operating procedures are introduced through the use of the results of war games. The spatial distribution of nodes is used as the basis for MANET internetwork topology generation.
{"title":"Analytical support for MANET internetworks from war game data","authors":"A. Allwright, Dennis Perisa, P. Pourbeik","doi":"10.1109/ISCIT.2007.4392130","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392130","url":null,"abstract":"There have been many studies in recent years reporting the performance and survivability of mobile ad-hoc networks (MANETs). These studies invariably consider the network as covering a relatively small geographic area. However, in many crises, such as may occur during disaster relief and military operations, a wide geographic area may require network coverage. In these circumstances, the infrastructure free mobile wireless communications features of MANETs may be critical in forming a satisfactory network. Given transmission range limitations within current MANET proposals, it is likely that providing network coverage to a wide geographic area would be problematic. This paper presents the results of a study on clustering in the spatial distribution of communication nodes. A realistic environment (e.g. topography and organisational limitations) and operating procedures are introduced through the use of the results of war games. The spatial distribution of nodes is used as the basis for MANET internetwork topology generation.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"129 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134259995","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 : 2007-12-04DOI: 10.1109/ISCIT.2007.4392259
Qin Zheng, Dan-li Xu
Traditional software system is always designed with characters like tight-coupling, which is difficult to be replanted and so on. A new design of credit scoring information system(CSIS) has been proposed in this paper, which includes the framework of CSIS based on service-oriented architecture (SOA), (the) seven-layer macro-SOA, three types of flow units in micro-SOA, and four-layer credits data warehouse. Some key issues and the solutions for implementation of the CSIS are also discussed in the paper. The new CSIS is loose-coupling. It is of flexibility and is easy to replant. Thus it is feasible for customization [2].
{"title":"A new design of the credits scoring information System","authors":"Qin Zheng, Dan-li Xu","doi":"10.1109/ISCIT.2007.4392259","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392259","url":null,"abstract":"Traditional software system is always designed with characters like tight-coupling, which is difficult to be replanted and so on. A new design of credit scoring information system(CSIS) has been proposed in this paper, which includes the framework of CSIS based on service-oriented architecture (SOA), (the) seven-layer macro-SOA, three types of flow units in micro-SOA, and four-layer credits data warehouse. Some key issues and the solutions for implementation of the CSIS are also discussed in the paper. The new CSIS is loose-coupling. It is of flexibility and is easy to replant. Thus it is feasible for customization [2].","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133132835","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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