Pub Date : 1998-10-05DOI: 10.1109/ICUPC.1998.733022
O. E. Kelly, F. Babich
This paper presents initial results on the application of Markov control process (MCP) theory to optimization of cost functions related to wireless communication channels subject to fading. Markov control process theory and Markov models of the fading channel are combined to solve the problem of designing a variable packet length protocol for the fading channel. The protocol selects the current packet length as a function of the recent fading history of the channel. This work makes use of previous empirical and analytical results in the construction of Markov descriptions of fast fading.
{"title":"Protocol optimization using discrete channel statistics","authors":"O. E. Kelly, F. Babich","doi":"10.1109/ICUPC.1998.733022","DOIUrl":"https://doi.org/10.1109/ICUPC.1998.733022","url":null,"abstract":"This paper presents initial results on the application of Markov control process (MCP) theory to optimization of cost functions related to wireless communication channels subject to fading. Markov control process theory and Markov models of the fading channel are combined to solve the problem of designing a variable packet length protocol for the fading channel. The protocol selects the current packet length as a function of the recent fading history of the channel. This work makes use of previous empirical and analytical results in the construction of Markov descriptions of fast fading.","PeriodicalId":341069,"journal":{"name":"ICUPC '98. IEEE 1998 International Conference on Universal Personal Communications. Conference Proceedings (Cat. No.98TH8384)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129441252","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 : 1998-10-05DOI: 10.1109/ICUPC.1998.733673
G. Colavolpe, R. Raheli
New noncoherent sequence detection algorithms for combined demodulation and decoding of coded amplitude/phase modulations transmitted over additive white Gaussian noise (AWGN) channels are presented. Optimal noncoherent sequence detection requires a tree search and a complexity exponentially increasing with the duration of the transmission. In order to realize simple suboptimal receivers based on the Viterbi algorithm (VA), approximate schemes are proposed, characterized by a performance which approaches that of coherent detection. In the proposed schemes the tradeoff between complexity and performance is simply controlled by a parameter referred to as implicit phase memory and the number of trellis states. These schemes represent a significant improvement over previous results.
{"title":"Noncoherent sequence detection of coded linear modulations","authors":"G. Colavolpe, R. Raheli","doi":"10.1109/ICUPC.1998.733673","DOIUrl":"https://doi.org/10.1109/ICUPC.1998.733673","url":null,"abstract":"New noncoherent sequence detection algorithms for combined demodulation and decoding of coded amplitude/phase modulations transmitted over additive white Gaussian noise (AWGN) channels are presented. Optimal noncoherent sequence detection requires a tree search and a complexity exponentially increasing with the duration of the transmission. In order to realize simple suboptimal receivers based on the Viterbi algorithm (VA), approximate schemes are proposed, characterized by a performance which approaches that of coherent detection. In the proposed schemes the tradeoff between complexity and performance is simply controlled by a parameter referred to as implicit phase memory and the number of trellis states. These schemes represent a significant improvement over previous results.","PeriodicalId":341069,"journal":{"name":"ICUPC '98. IEEE 1998 International Conference on Universal Personal Communications. Conference Proceedings (Cat. No.98TH8384)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114859789","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 : 1998-10-05DOI: 10.1109/ICUPC.1998.732804
E. Metaxakis, A. Tzimas, G. Kalivas
Portable communication systems with multiservice capabilities are in ever increasing demand. This together with the rapid advances in electronic technology and integration strongly favours the development of small size low power wireless terminals. An attractive technique to achieve compactness and low cost is to employ tele-IF transceiver architecture. We present an all-digital low complexity baseband receiver for a DECT radio system employing the direct conversion approach. The receiver is based on a newly developed symbol rate differential detector. We also investigate the performance of feed-forward algorithms for automatic frequency correction, symbol timing estimation and slot synchronization.
{"title":"A low complexity baseband receiver for direct conversion DECT-based portable communication systems","authors":"E. Metaxakis, A. Tzimas, G. Kalivas","doi":"10.1109/ICUPC.1998.732804","DOIUrl":"https://doi.org/10.1109/ICUPC.1998.732804","url":null,"abstract":"Portable communication systems with multiservice capabilities are in ever increasing demand. This together with the rapid advances in electronic technology and integration strongly favours the development of small size low power wireless terminals. An attractive technique to achieve compactness and low cost is to employ tele-IF transceiver architecture. We present an all-digital low complexity baseband receiver for a DECT radio system employing the direct conversion approach. The receiver is based on a newly developed symbol rate differential detector. We also investigate the performance of feed-forward algorithms for automatic frequency correction, symbol timing estimation and slot synchronization.","PeriodicalId":341069,"journal":{"name":"ICUPC '98. IEEE 1998 International Conference on Universal Personal Communications. Conference Proceedings (Cat. No.98TH8384)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124522596","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 : 1998-10-05DOI: 10.1109/ICUPC.1998.732798
R. Atkinson, J. Dunlop
The migration of UMTS carrier frequencies to the 2 GHz band has stimulated interest in radio coverage in urban environments. This paper examines the problem of poor signal quality close to buildings. It uses simulation based on approximate propagation models in a "generic" urban environment to estimate the relationship between size of coverage black spots and distance from the serving base station. Consideration is also given to the possibility of using channels allocated to in-building picocells as a means of mitigating against coverage black spots.
{"title":"Potential for mobile coverage improvement in urban environments","authors":"R. Atkinson, J. Dunlop","doi":"10.1109/ICUPC.1998.732798","DOIUrl":"https://doi.org/10.1109/ICUPC.1998.732798","url":null,"abstract":"The migration of UMTS carrier frequencies to the 2 GHz band has stimulated interest in radio coverage in urban environments. This paper examines the problem of poor signal quality close to buildings. It uses simulation based on approximate propagation models in a \"generic\" urban environment to estimate the relationship between size of coverage black spots and distance from the serving base station. Consideration is also given to the possibility of using channels allocated to in-building picocells as a means of mitigating against coverage black spots.","PeriodicalId":341069,"journal":{"name":"ICUPC '98. IEEE 1998 International Conference on Universal Personal Communications. Conference Proceedings (Cat. No.98TH8384)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132413118","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 : 1998-10-05DOI: 10.1109/ICUPC.1998.733059
F. Peyrard, T. Val, J. Mercier
Specification, validation and simulation are the three stages before any implementation of a protocol. A specification method of protocols for hybrid WLANs was defined, and the associated tools allowed the generating of network simulator input files. The LLC and MAC layers of these WLANs were increased according to the Opnet simulator characteristics. These new layers have allowed us to simulate ad-hoc WLAN with and without relay of frames. The comparative analysis of the results confirmed the increase in performance of the communications with relays, without overloading the network by the relayed frames. These simulations also allowed us to refine the protocols of each layer and show up any omissions and design errors. In fact, this proposed mechanism of localization and network knowledge would still increase the performances of this type of WLAN.
{"title":"Simulations of ad-hoc WLAN with or without relay","authors":"F. Peyrard, T. Val, J. Mercier","doi":"10.1109/ICUPC.1998.733059","DOIUrl":"https://doi.org/10.1109/ICUPC.1998.733059","url":null,"abstract":"Specification, validation and simulation are the three stages before any implementation of a protocol. A specification method of protocols for hybrid WLANs was defined, and the associated tools allowed the generating of network simulator input files. The LLC and MAC layers of these WLANs were increased according to the Opnet simulator characteristics. These new layers have allowed us to simulate ad-hoc WLAN with and without relay of frames. The comparative analysis of the results confirmed the increase in performance of the communications with relays, without overloading the network by the relayed frames. These simulations also allowed us to refine the protocols of each layer and show up any omissions and design errors. In fact, this proposed mechanism of localization and network knowledge would still increase the performances of this type of WLAN.","PeriodicalId":341069,"journal":{"name":"ICUPC '98. IEEE 1998 International Conference on Universal Personal Communications. Conference Proceedings (Cat. No.98TH8384)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130179869","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 : 1998-10-05DOI: 10.1109/ICUPC.1998.733040
Yuping Zhao
Adaptive modulation with varying data rate is an attractive scheme to increase the transmission data rate for mobile radio communications. The radio link adaptation (LA) algorithm is an important issue for such a system; however a theoretical analysis of LA algorithms has not previously been carried out. This paper presents a performance analysis of the LA algorithms for slow fading mobile radio channels. The LA algorithms based on the received signal level are studied; the expression of the radio link outage probability and transmission data rate are derived. The simulations were performed in the GSM communication environment, which gave identical results to the theoretical analysis. The results can be used to determine suitable LA algorithms for adaptive modulation under different conditions.
{"title":"Theoretical study of link adaptation algorithms for adaptive modulation in wireless mobile communication systems","authors":"Yuping Zhao","doi":"10.1109/ICUPC.1998.733040","DOIUrl":"https://doi.org/10.1109/ICUPC.1998.733040","url":null,"abstract":"Adaptive modulation with varying data rate is an attractive scheme to increase the transmission data rate for mobile radio communications. The radio link adaptation (LA) algorithm is an important issue for such a system; however a theoretical analysis of LA algorithms has not previously been carried out. This paper presents a performance analysis of the LA algorithms for slow fading mobile radio channels. The LA algorithms based on the received signal level are studied; the expression of the radio link outage probability and transmission data rate are derived. The simulations were performed in the GSM communication environment, which gave identical results to the theoretical analysis. The results can be used to determine suitable LA algorithms for adaptive modulation under different conditions.","PeriodicalId":341069,"journal":{"name":"ICUPC '98. IEEE 1998 International Conference on Universal Personal Communications. Conference Proceedings (Cat. No.98TH8384)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130948800","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 : 1998-10-05DOI: 10.1109/ICUPC.1998.733702
J. Karlsson, S. Mazur
The link level performance gain of using multiple antennas in CDMA mobile stations is theoretically investigated and the corresponding capacity gain is evaluated by means of system level simulations. Depending on the channel model, the maximum ratio combiner improves the performance by 4-6 dB when the number of antennas is increased from one to two, and by another 3-5 dB when the number of antennas is increased from two to four. The resulting capacity gain is close to a direct translation of the link level gain. The optimum combiner is capable of completely suppressing a number of interfering rays equal to the number of antennas minus one. In contrast to the uplink, the downlink can greatly benefit from the suppression of a few interfering rays, leading to an additional substantial gain in downlink capacity.
{"title":"Interference suppression in CDMA mobile stations using multiple antennas","authors":"J. Karlsson, S. Mazur","doi":"10.1109/ICUPC.1998.733702","DOIUrl":"https://doi.org/10.1109/ICUPC.1998.733702","url":null,"abstract":"The link level performance gain of using multiple antennas in CDMA mobile stations is theoretically investigated and the corresponding capacity gain is evaluated by means of system level simulations. Depending on the channel model, the maximum ratio combiner improves the performance by 4-6 dB when the number of antennas is increased from one to two, and by another 3-5 dB when the number of antennas is increased from two to four. The resulting capacity gain is close to a direct translation of the link level gain. The optimum combiner is capable of completely suppressing a number of interfering rays equal to the number of antennas minus one. In contrast to the uplink, the downlink can greatly benefit from the suppression of a few interfering rays, leading to an additional substantial gain in downlink capacity.","PeriodicalId":341069,"journal":{"name":"ICUPC '98. IEEE 1998 International Conference on Universal Personal Communications. Conference Proceedings (Cat. No.98TH8384)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133609173","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 : 1998-10-05DOI: 10.1109/ICUPC.1998.733017
Z. Rong, S. Gray
Beamforming and adaptive array processing are now being considered for 3/sup rd/ generation cellular communication systems. On the downlink, beamforming techniques and spatial division multiple access (SDMA) can reduce the adverse effects high data rate mobiles have upon the system capacity in a code division multiple access (CDMA) communications system. For 3/sup rd/ Generation systems, one approach is to assign SDMA channels to low mobility/high data rate mobile stations and provide a low data rate service via a sectorized antenna. The use of SDMA for high rate mobiles requires the base station to accurately estimate the direction of multipaths between the base station and SDMA mobile stations. This paper presents a simple, but intuitive model for analyzing the beamforming loss due to inaccuracies in estimating the direction of arrival of multipaths from SDMA mobiles and the loss due to periodic update of beam patterns to SDMA mobiles.
{"title":"Beamforming loss due to tracking error in downlink SDMA","authors":"Z. Rong, S. Gray","doi":"10.1109/ICUPC.1998.733017","DOIUrl":"https://doi.org/10.1109/ICUPC.1998.733017","url":null,"abstract":"Beamforming and adaptive array processing are now being considered for 3/sup rd/ generation cellular communication systems. On the downlink, beamforming techniques and spatial division multiple access (SDMA) can reduce the adverse effects high data rate mobiles have upon the system capacity in a code division multiple access (CDMA) communications system. For 3/sup rd/ Generation systems, one approach is to assign SDMA channels to low mobility/high data rate mobile stations and provide a low data rate service via a sectorized antenna. The use of SDMA for high rate mobiles requires the base station to accurately estimate the direction of multipaths between the base station and SDMA mobile stations. This paper presents a simple, but intuitive model for analyzing the beamforming loss due to inaccuracies in estimating the direction of arrival of multipaths from SDMA mobiles and the loss due to periodic update of beam patterns to SDMA mobiles.","PeriodicalId":341069,"journal":{"name":"ICUPC '98. IEEE 1998 International Conference on Universal Personal Communications. Conference Proceedings (Cat. No.98TH8384)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133300955","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 : 1998-10-05DOI: 10.1109/ICUPC.1998.732809
M. Sawada, N. Tani, M. Miki, Y. Maruyama
This paper first describes the advanced mobile multimedia services required in the third-generation system. Next, we present essential network techniques for the mobile multimedia services.
{"title":"Advanced mobile multimedia services and applied network techniques","authors":"M. Sawada, N. Tani, M. Miki, Y. Maruyama","doi":"10.1109/ICUPC.1998.732809","DOIUrl":"https://doi.org/10.1109/ICUPC.1998.732809","url":null,"abstract":"This paper first describes the advanced mobile multimedia services required in the third-generation system. Next, we present essential network techniques for the mobile multimedia services.","PeriodicalId":341069,"journal":{"name":"ICUPC '98. IEEE 1998 International Conference on Universal Personal Communications. Conference Proceedings (Cat. No.98TH8384)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133122170","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 : 1998-10-05DOI: 10.1109/ICUPC.1998.733034
Guido Riva, M. Frullone, C. Passerini, G. Falciasecca
Network planning of modern personal communications systems has been accomplished so far on a manual basis by means of heuristic solutions, but this process is quite time consuming and errors are frequent. Recently, a number of automatic procedures for optimally locating base stations have been developed. In the present paper we try to highlight the influence of the adopted multiple access scheme on the optimal base site locations, and therefore we analyse if and where the deployment of the base stations is eventually influenced. This aspect could be quite interesting in order to compare two existing systems and their flexibility in network optimization; but perhaps it is even more challenging to evaluate how a migration from one system to the other (e.g. from GSM to CDMA) can exploit the present base mesh and thus which difficulties the of the new system has to cope with.
{"title":"Impact of the multiple access scheme on optimal site positioning","authors":"Guido Riva, M. Frullone, C. Passerini, G. Falciasecca","doi":"10.1109/ICUPC.1998.733034","DOIUrl":"https://doi.org/10.1109/ICUPC.1998.733034","url":null,"abstract":"Network planning of modern personal communications systems has been accomplished so far on a manual basis by means of heuristic solutions, but this process is quite time consuming and errors are frequent. Recently, a number of automatic procedures for optimally locating base stations have been developed. In the present paper we try to highlight the influence of the adopted multiple access scheme on the optimal base site locations, and therefore we analyse if and where the deployment of the base stations is eventually influenced. This aspect could be quite interesting in order to compare two existing systems and their flexibility in network optimization; but perhaps it is even more challenging to evaluate how a migration from one system to the other (e.g. from GSM to CDMA) can exploit the present base mesh and thus which difficulties the of the new system has to cope with.","PeriodicalId":341069,"journal":{"name":"ICUPC '98. IEEE 1998 International Conference on Universal Personal Communications. Conference Proceedings (Cat. No.98TH8384)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133772476","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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