Pub Date : 2000-12-17DOI: 10.1109/ICPWC.2000.905782
M. Ghogho, A. Swami, T. Durrani
We address the problem of blind estimation of carrier offset in the presence of an unknown multipath propagation channel for linearly modulated signals. The goal is to decouple the two estimation problems. Here, we capitalize on the second and higher (typically fourth-) order noncircularity of the transmitted signals. We focus on QAM and PSK-type signals. We analyze both frequency and phase estimators. We study the performance of the proposed estimators, and compare them with the corresponding Cramer-Rao bounds which are also derived. The theoretical results are verified via simulations.
{"title":"Blind estimation of frequency offset in the presence of unknown multipath","authors":"M. Ghogho, A. Swami, T. Durrani","doi":"10.1109/ICPWC.2000.905782","DOIUrl":"https://doi.org/10.1109/ICPWC.2000.905782","url":null,"abstract":"We address the problem of blind estimation of carrier offset in the presence of an unknown multipath propagation channel for linearly modulated signals. The goal is to decouple the two estimation problems. Here, we capitalize on the second and higher (typically fourth-) order noncircularity of the transmitted signals. We focus on QAM and PSK-type signals. We analyze both frequency and phase estimators. We study the performance of the proposed estimators, and compare them with the corresponding Cramer-Rao bounds which are also derived. The theoretical results are verified via simulations.","PeriodicalId":260472,"journal":{"name":"2000 IEEE International Conference on Personal Wireless Communications. Conference Proceedings (Cat. No.00TH8488)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127895636","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 : 2000-12-17DOI: 10.1109/ICPWC.2000.905794
Xue Yisheng, Zhuang Xuelong
Soft-decision adaptive decoding of space-time trellis code (STTC) used in TDMA communication links is considered. To fully utilize preambles of successive downlink slots, bi-directional processing (BD-P) is proposed, which performs forward and backward adaptive decoding with two-step LMS (TSLMS) based channel tracking. Computer simulation shows that the proposed decoder can improve system performance distinctly on slowly or moderately fast time-varying channels. Besides, the computational complexity of the proposed BD-TSLMS decoder is modest.
{"title":"A new soft-decision adaptive decoder for space-time trellis code","authors":"Xue Yisheng, Zhuang Xuelong","doi":"10.1109/ICPWC.2000.905794","DOIUrl":"https://doi.org/10.1109/ICPWC.2000.905794","url":null,"abstract":"Soft-decision adaptive decoding of space-time trellis code (STTC) used in TDMA communication links is considered. To fully utilize preambles of successive downlink slots, bi-directional processing (BD-P) is proposed, which performs forward and backward adaptive decoding with two-step LMS (TSLMS) based channel tracking. Computer simulation shows that the proposed decoder can improve system performance distinctly on slowly or moderately fast time-varying channels. Besides, the computational complexity of the proposed BD-TSLMS decoder is modest.","PeriodicalId":260472,"journal":{"name":"2000 IEEE International Conference on Personal Wireless Communications. Conference Proceedings (Cat. No.00TH8488)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128138464","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 : 2000-12-17DOI: 10.1109/ICPWC.2000.905834
P. Panchapakesan, D. Manjunath
Routing information updates, exchange of congestion control information, and synchronisation in distributed computation environments may require that some information from all the nodes be broadcast to all the nodes in the network. We consider such all-to-all broadcast, or gossiping as it is known in the literature, in multihop packet radio networks in an ad hoc network setup. Scheduling of transmissions in a packet radio network can be done either deterministically or randomly. The use of deterministic scheduling algorithms for ad hoc (multihop radio) networks whose topologies are dynamic may not be practical and transmission scheduling with randomised transmissions may be better suited in these networks. We study the performance of deterministic and randomised algorithms for scheduling for a class of communication requirements, called gossiping, in multihop radio networks.
{"title":"Transmission scheduling for gossiping in multihop packet radio networks","authors":"P. Panchapakesan, D. Manjunath","doi":"10.1109/ICPWC.2000.905834","DOIUrl":"https://doi.org/10.1109/ICPWC.2000.905834","url":null,"abstract":"Routing information updates, exchange of congestion control information, and synchronisation in distributed computation environments may require that some information from all the nodes be broadcast to all the nodes in the network. We consider such all-to-all broadcast, or gossiping as it is known in the literature, in multihop packet radio networks in an ad hoc network setup. Scheduling of transmissions in a packet radio network can be done either deterministically or randomly. The use of deterministic scheduling algorithms for ad hoc (multihop radio) networks whose topologies are dynamic may not be practical and transmission scheduling with randomised transmissions may be better suited in these networks. We study the performance of deterministic and randomised algorithms for scheduling for a class of communication requirements, called gossiping, in multihop radio networks.","PeriodicalId":260472,"journal":{"name":"2000 IEEE International Conference on Personal Wireless Communications. Conference Proceedings (Cat. No.00TH8488)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128400124","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 : 2000-12-17DOI: 10.1109/ICPWC.2000.905833
Apurv Gupta, D. Sanghi
We present a framework for providing guaranteed quality of service in ad-hoc networks given reasonable limits on rate of change of topology. This is achieved at the expense of higher network resources than required by the flow specification itself. We quantify these extra resources and suggest changes that need to be incorporated in the buffer requirements and the play out times. Central to providing QoS guarantees is the concept of local route repair and buffer flush. The onus for restoring a failed in-use path is on the upstream node of the failed link. The route restoration time after a failure has important consequences on the performance of the proposed scheme and so we propose to add this functionality to the QoS module in general. We also suggest a protocol to reduce this latency under the assumption of slow rate of change of topology. The analysis can be extended to slightly relaxed assumptions on rate of change of topology. But when the topology changes too fast, it shall not be possible for any protocol with reasonable overhead to provide QoS guarantees.
{"title":"QoS support in mobile ad-hoc networks","authors":"Apurv Gupta, D. Sanghi","doi":"10.1109/ICPWC.2000.905833","DOIUrl":"https://doi.org/10.1109/ICPWC.2000.905833","url":null,"abstract":"We present a framework for providing guaranteed quality of service in ad-hoc networks given reasonable limits on rate of change of topology. This is achieved at the expense of higher network resources than required by the flow specification itself. We quantify these extra resources and suggest changes that need to be incorporated in the buffer requirements and the play out times. Central to providing QoS guarantees is the concept of local route repair and buffer flush. The onus for restoring a failed in-use path is on the upstream node of the failed link. The route restoration time after a failure has important consequences on the performance of the proposed scheme and so we propose to add this functionality to the QoS module in general. We also suggest a protocol to reduce this latency under the assumption of slow rate of change of topology. The analysis can be extended to slightly relaxed assumptions on rate of change of topology. But when the topology changes too fast, it shall not be possible for any protocol with reasonable overhead to provide QoS guarantees.","PeriodicalId":260472,"journal":{"name":"2000 IEEE International Conference on Personal Wireless Communications. Conference Proceedings (Cat. No.00TH8488)","volume":"216 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134256587","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 : 2000-12-17DOI: 10.1109/ICPWC.2000.905912
J. Khan
This paper addresses the development of an adaptive packet based reservation multiple access protocol to transmit multimedia traffic over a wireless network. The proposed multiple access protocol is an adaptive version of the BRTDMA (block reservation time division multiple access) protocol where resources are allocated based on traffic type in a network. Resources are allocated in such a way that the quality of service parameters of different class of traffic can be maintained. The resource allocation algorithm allocates resources based on QoS requirements of different types of traffic. Simulation results are presented to show the effectiveness of adaptive resource allocation techniques.
{"title":"An adaptive reservation packet switched multiple access protocol for a wireless network","authors":"J. Khan","doi":"10.1109/ICPWC.2000.905912","DOIUrl":"https://doi.org/10.1109/ICPWC.2000.905912","url":null,"abstract":"This paper addresses the development of an adaptive packet based reservation multiple access protocol to transmit multimedia traffic over a wireless network. The proposed multiple access protocol is an adaptive version of the BRTDMA (block reservation time division multiple access) protocol where resources are allocated based on traffic type in a network. Resources are allocated in such a way that the quality of service parameters of different class of traffic can be maintained. The resource allocation algorithm allocates resources based on QoS requirements of different types of traffic. Simulation results are presented to show the effectiveness of adaptive resource allocation techniques.","PeriodicalId":260472,"journal":{"name":"2000 IEEE International Conference on Personal Wireless Communications. Conference Proceedings (Cat. No.00TH8488)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133306173","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 : 2000-12-17DOI: 10.1109/ICPWC.2000.905819
S. Mitra, S. DasBit
A simple load balancing technique is proposed. It is basically a combination of both the dynamic channel assignment and channel borrowing techniques. All the cells of the system are divided into six groups, each group under one mobile switching centre (MSC). Initially a fixed number of channels are assigned to each cell under each mobile switching centre. Finally the channels are distributed among the cells as per their requirement. In the case of sudden channel demand under one mobile switching centre, the cell which needs more channel can borrow a channel from one of its compact pattern cells belonging to the same group (to be defined) with it by exchanging a negligible number of messages among the different components of the network. If there is no probable lender cell in the group, the MSC of the borrower cell can lend it from another MSC.
{"title":"A load balancing strategy using dynamic channel assignment and channel borrowing in cellular mobile environment","authors":"S. Mitra, S. DasBit","doi":"10.1109/ICPWC.2000.905819","DOIUrl":"https://doi.org/10.1109/ICPWC.2000.905819","url":null,"abstract":"A simple load balancing technique is proposed. It is basically a combination of both the dynamic channel assignment and channel borrowing techniques. All the cells of the system are divided into six groups, each group under one mobile switching centre (MSC). Initially a fixed number of channels are assigned to each cell under each mobile switching centre. Finally the channels are distributed among the cells as per their requirement. In the case of sudden channel demand under one mobile switching centre, the cell which needs more channel can borrow a channel from one of its compact pattern cells belonging to the same group (to be defined) with it by exchanging a negligible number of messages among the different components of the network. If there is no probable lender cell in the group, the MSC of the borrower cell can lend it from another MSC.","PeriodicalId":260472,"journal":{"name":"2000 IEEE International Conference on Personal Wireless Communications. Conference Proceedings (Cat. No.00TH8488)","volume":" 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113949081","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 : 2000-12-17DOI: 10.1109/ICPWC.2000.905801
A. Ramesh, A. Chockalingam
We derive the system throughput and outage probability performance of adaptive modulation with optimal power control in log-normal shadowing and multipath Rayleigh fading channels. We propose two objective functions, namely, maximum SIR optimum power control and minimum outage probability optimum power control. A dynamic programming-based solution to find the optimum transmit power vector is presented. System performance achieved using the proposed objective functions is compared with the performance achieved using other objective functions considered by Qiu et al., (1999). Our results show that: (a) in terms of total system throughput, adaptive modulation with optimum power control gives the best performance compared to other schemes; (b) in terms of outage probability, minimum outage probability optimum power control gives the best performance; and (c) maximum SIR optimum power control benefits every user in the system by evenly distributing the system capacity.
{"title":"Performance analysis of adaptive modulation with optimum power control in cellular systems","authors":"A. Ramesh, A. Chockalingam","doi":"10.1109/ICPWC.2000.905801","DOIUrl":"https://doi.org/10.1109/ICPWC.2000.905801","url":null,"abstract":"We derive the system throughput and outage probability performance of adaptive modulation with optimal power control in log-normal shadowing and multipath Rayleigh fading channels. We propose two objective functions, namely, maximum SIR optimum power control and minimum outage probability optimum power control. A dynamic programming-based solution to find the optimum transmit power vector is presented. System performance achieved using the proposed objective functions is compared with the performance achieved using other objective functions considered by Qiu et al., (1999). Our results show that: (a) in terms of total system throughput, adaptive modulation with optimum power control gives the best performance compared to other schemes; (b) in terms of outage probability, minimum outage probability optimum power control gives the best performance; and (c) maximum SIR optimum power control benefits every user in the system by evenly distributing the system capacity.","PeriodicalId":260472,"journal":{"name":"2000 IEEE International Conference on Personal Wireless Communications. Conference Proceedings (Cat. No.00TH8488)","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122465056","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 : 2000-12-17DOI: 10.1109/ICPWC.2000.905846
S. Jamadagni, M. Umesh
A software defined radio (SDR) is a completely configurable radio that can be programmed in software to define its functionality. An SDR handset can be modified to perform different functions at different times through software downloads. Software radios give the ability to add or remove software components or allow plug and play of software components. This allows the SDR handset to be specifically tailored to the applications expected to run on the handset resulting in great flexibility. The downloadable software components can be signal processing components, protocol components or application components. The SDR forum is evolving a download protocol in liaison with the MExE (mobile execution environment) activities of the ETSI forum. Software download overheads are an important issue in realizing viable software radios. Download requests can be initiated by the user terminal, which is termed as a PULL operation or the base station (or the download server) can initiate the download process which is termed as a PUSH operation. We assert that PUSH is an important mode of software download and explore a download architecture that involves PUSH.
{"title":"A PUSH download architecture for software defined radios","authors":"S. Jamadagni, M. Umesh","doi":"10.1109/ICPWC.2000.905846","DOIUrl":"https://doi.org/10.1109/ICPWC.2000.905846","url":null,"abstract":"A software defined radio (SDR) is a completely configurable radio that can be programmed in software to define its functionality. An SDR handset can be modified to perform different functions at different times through software downloads. Software radios give the ability to add or remove software components or allow plug and play of software components. This allows the SDR handset to be specifically tailored to the applications expected to run on the handset resulting in great flexibility. The downloadable software components can be signal processing components, protocol components or application components. The SDR forum is evolving a download protocol in liaison with the MExE (mobile execution environment) activities of the ETSI forum. Software download overheads are an important issue in realizing viable software radios. Download requests can be initiated by the user terminal, which is termed as a PULL operation or the base station (or the download server) can initiate the download process which is termed as a PUSH operation. We assert that PUSH is an important mode of software download and explore a download architecture that involves PUSH.","PeriodicalId":260472,"journal":{"name":"2000 IEEE International Conference on Personal Wireless Communications. Conference Proceedings (Cat. No.00TH8488)","volume":"124 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124558931","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 : 2000-12-17DOI: 10.1109/ICPWC.2000.905772
S. Medidi, E.A. Ashcroft
Route augmentation based connection rerouting techniques for handoff provide a level of speed and simplicity that can potentially reduce handoff latency and signaling costs, but can become terribly inefficient if the connection route begins to loop itself. We address this issue in this paper by introducing a framework for efficient handoff in which the route information of the call is integrated in the decision process of connection rerouting. A key feature in our approach is that during the handoff the switch covering the mobile host determines the type of handoff that needs to be initiated based on the existing route information of the call that is being handed off and the location of the mobile host. In current handoff techniques in the literature, the switches are not capable of making such choices. This algorithm is aimed at improving the efficiency of the route in the route augmentation technique by avoiding loops.
{"title":"Handoff in mobile wireless ATM networks: an integrated approach","authors":"S. Medidi, E.A. Ashcroft","doi":"10.1109/ICPWC.2000.905772","DOIUrl":"https://doi.org/10.1109/ICPWC.2000.905772","url":null,"abstract":"Route augmentation based connection rerouting techniques for handoff provide a level of speed and simplicity that can potentially reduce handoff latency and signaling costs, but can become terribly inefficient if the connection route begins to loop itself. We address this issue in this paper by introducing a framework for efficient handoff in which the route information of the call is integrated in the decision process of connection rerouting. A key feature in our approach is that during the handoff the switch covering the mobile host determines the type of handoff that needs to be initiated based on the existing route information of the call that is being handed off and the location of the mobile host. In current handoff techniques in the literature, the switches are not capable of making such choices. This algorithm is aimed at improving the efficiency of the route in the route augmentation technique by avoiding loops.","PeriodicalId":260472,"journal":{"name":"2000 IEEE International Conference on Personal Wireless Communications. Conference Proceedings (Cat. No.00TH8488)","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127653934","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 : 2000-12-17DOI: 10.1109/ICPWC.2000.905913
Jay P. Singh, S. Adlakha, Subrat Kar, S. Prasad
With the ever increasing demand for easy portability and mobility of devices supporting diverse mobile multimedia applications, the need for the adaptation of a broadband infrastructure to a wireless scenario has arisen. Mobile multimedia networks like the wireless ATM are faced with challenges relating to wireless channel access. In this paper, we propose and simulate policies vis-a-vis medium access in wireless ATM networks. We also discuss the modelling of traffic generators, the evaluation of delay and buffer length bounds and the implementation of a WATM MAC simulator.
{"title":"Proposal, simulation and performance appraisal of an optimal medium access protocol for wireless ATM networks","authors":"Jay P. Singh, S. Adlakha, Subrat Kar, S. Prasad","doi":"10.1109/ICPWC.2000.905913","DOIUrl":"https://doi.org/10.1109/ICPWC.2000.905913","url":null,"abstract":"With the ever increasing demand for easy portability and mobility of devices supporting diverse mobile multimedia applications, the need for the adaptation of a broadband infrastructure to a wireless scenario has arisen. Mobile multimedia networks like the wireless ATM are faced with challenges relating to wireless channel access. In this paper, we propose and simulate policies vis-a-vis medium access in wireless ATM networks. We also discuss the modelling of traffic generators, the evaluation of delay and buffer length bounds and the implementation of a WATM MAC simulator.","PeriodicalId":260472,"journal":{"name":"2000 IEEE International Conference on Personal Wireless Communications. Conference Proceedings (Cat. No.00TH8488)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127929904","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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