{"title":"Quality assessment for pre-detection diversity switching","authors":"A. Brandao, L. Lopes, D. McLernon","doi":"10.1109/PIMRC.1995.480934","DOIUrl":"https://doi.org/10.1109/PIMRC.1995.480934","url":null,"abstract":"In cellular mobile systems the on-line assessment of a radio link performance is normally associated with measurements of the received signal power, and is taken before signal demodulation. It determines the thresholds for handover policies, transmitting power control, diversity switching schemes, and other operations. However, a large received signal power does not necessarily mean \"good quality\" when it comes to considering radio links corrupted by cochannel interference, multipath propagation and background noise. In such cases, a better parameter that can be used to assess the signal quality is the signal-to-interference-plus-noise power ratio (SINR). Although this quality factor parameter is well-known in the literature, little has been written about how to measure it in a practical context. This article presents a method for the SINR estimation applied to a system using the Digital European Cordless Telecommunications (DECT) specification, but it can also be used by any other system employing constant modulus signals.","PeriodicalId":433500,"journal":{"name":"Proceedings of 6th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125276456","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}
{"title":"A Bayesian receiver for asynchronous code division multiple access communications","authors":"B. Mulgrew, E. S. Warner, P. Grant","doi":"10.1109/PIMRC.1995.477091","DOIUrl":"https://doi.org/10.1109/PIMRC.1995.477091","url":null,"abstract":"","PeriodicalId":433500,"journal":{"name":"Proceedings of 6th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"124 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116380140","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}
{"title":"Adaptive co-channel interference suppression in mobile communications satellite systems","authors":"Shiwei Gao, K. Wong","doi":"10.1109/PIMRC.1995.476409","DOIUrl":"https://doi.org/10.1109/PIMRC.1995.476409","url":null,"abstract":"A new adaptive approach is proposed for co-channel interference cancellation in the uplink of the future mobile communications satellite systems employing multiple co-channel beams. The approach requires no reference signals and is applicable to both phased array and multiple beam antennas. A modular cascade structure is also developed for its implementations. Its performance is demonstrated by computer simulations.","PeriodicalId":433500,"journal":{"name":"Proceedings of 6th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116574322","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}
{"title":"Equal BER with successive interference cancellation DS-CDMA systems on AWGN and Ricean channels","authors":"G. Mazzini","doi":"10.1109/PIMRC.1995.480965","DOIUrl":"https://doi.org/10.1109/PIMRC.1995.480965","url":null,"abstract":"An interference cancellation scheme, based on successive cancellation with decided information bit feedback, is presented, and the performance analyzed in order to obtain the same bit error probability (BER) for each user, when channel estimation and power control are considered to be ideal. The analysis is carried out to obtain the same, optimal, performance on each channel. Furthermore, a possible approximation is introduced to develop an easy power list algorithm and is validated with numerical results. Some considerations both on receiver and transmitted total power gain with respect to the classical integration-and-dump receiver structure are reported.","PeriodicalId":433500,"journal":{"name":"Proceedings of 6th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116582727","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}
J. Hämäläinen, H. Jokinen, Z. Honkasalo, R. Fehlmann
{"title":"Multi-slot packet radio air interface to TDMA systems-variable rate reservation access (VRRA)","authors":"J. Hämäläinen, H. Jokinen, Z. Honkasalo, R. Fehlmann","doi":"10.1109/PIMRC.1995.476914","DOIUrl":"https://doi.org/10.1109/PIMRC.1995.476914","url":null,"abstract":"This paper presents a new variable rate reservation access (VRRA) media access control (MAC) for packet radio systems. The VRRA algorithm is designed for TDMA based cellular networks, especially GSM. It utilizes alternatively one or multiple time slots per TDMA frame, depending on the requirements of the network operator and the user. The paper describes the VRRA MAC algorithm with simulation results. The simulation results are given for the GSM system operating in both single slot and multi-slot mode.","PeriodicalId":433500,"journal":{"name":"Proceedings of 6th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114180065","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}
{"title":"Equalization of indoor fading channels with differentially coherent demodulation","authors":"A. Masoomzadeh-Fard, S. Pasupathy","doi":"10.1109/PIMRC.1995.476268","DOIUrl":"https://doi.org/10.1109/PIMRC.1995.476268","url":null,"abstract":"We employ a fractionally spaced decision feedback equalizer for indoor fading channels and give the relevant analytical and simulated performance results in terms of Doppler frequency. An upper limit is determined for the channel variations which can be tracked by the equalizer. Also, the effect of error propagation on the performance is evaluated. Finally, a nonlinear decision-based equalizer compatible with differentially coherent PSK is proposed. This equalization scheme is appropriate whenever conventional equalizers are not able to track channel phase variations. Our simulation results indicate that, for channels with spectral nulls, equalization will be achieved successfully with the proposed scheme, whereas linear equalizers, either with coherent or non-coherent detection, fail.","PeriodicalId":433500,"journal":{"name":"Proceedings of 6th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114468684","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}
{"title":"On the deorthogonalization of ODS-CDMA 4-PSK in frequency-nonselective shadowed Rician fading","authors":"P. Pawlowski","doi":"10.1109/PIMRC.1995.480904","DOIUrl":"https://doi.org/10.1109/PIMRC.1995.480904","url":null,"abstract":"Using a conventional demodulator, a sufficient condition to maintain orthogonal direct sequence-code-division multiple access (ODS-CDMA) codeword orthogonality is constant relative channel amplitude over the codeword duration. Fading produces a fluctuating amplitude that deorthogonalizes the codewords, resulting in an additional noise similar to the multiaccess interference (MAI) found in asynchronous DS-CDMA. For ODS-CDMA 4-PSK in a frequency-nonselective, shadowed Rician fading channel, we derive and evaluate: (i) an exact expression for the uncoded bit error probability, and (ii) an upper bound for the convolutionally-coded bit error probability. We find that the degradation to BER depends on both the fading parameters and the ODS-CDMA channel loading.","PeriodicalId":433500,"journal":{"name":"Proceedings of 6th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121888269","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}
{"title":"Performance of DPSK commutation signalling with RAKE receivers in multipath channels","authors":"P. Krishnamurthy, H. Leib","doi":"10.1109/PIMRC.1995.480910","DOIUrl":"https://doi.org/10.1109/PIMRC.1995.480910","url":null,"abstract":"The authors consider an anti-multipath modulation scheme called commutation signalling. The anti-multipath capabilities are studied by the use of computer simulations. In particular, multipath Rayleigh fading channels and multipath non-fading channels are considered with the assumption of a knowledge of the multipath delays at the receiver. The effects of correlation noise as the number of paths increases and the advantages or disadvantages of using the weaker multipath components in decision making are presented.","PeriodicalId":433500,"journal":{"name":"Proceedings of 6th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"174 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129491127","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}
{"title":"Analysis and simulation of a CDMA PCS indoor system with distributed antennae","authors":"Jim Yang","doi":"10.1109/PIMRC.1995.477322","DOIUrl":"https://doi.org/10.1109/PIMRC.1995.477322","url":null,"abstract":"-Distributed antennae play an important role in PCS CDMA indoor system based on wideband cellular standard EIA/TIA/IS-95. The trade-off between captured energy and self interference is crucial for distributed antenna system design. This paper examines the relationships between diversity gain and the number of distributed antenna elements with various numbers of diversity receiver branches. The diversity gain factor is derived based on a wideband tapped delay line multipath fading model. Frame-Error-Rate (FER) improvement is demonstrated by using a simulation system based on TIA/EIA/IS-95. A three branch modified maximalratio receiver with a search engine can provide nearly the same diversity gain as that of a four branch maximal-ratio receiver for a four element distributed antenna system. Simulations show that the three branch modified diversity receiver provides less than 1% FER when the number of users per cell in a multiple omni-cell environment is less than 10, and the number of distributed antenna elements is between two and five. FER is more sensitive to the number of antenna elements, when more users are served in the system. FER could also be improved by reducing the resolution of the diversity receiver branches to one half of the chip interval.","PeriodicalId":433500,"journal":{"name":"Proceedings of 6th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128338268","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}
{"title":"Modeling of wideband mobile radio channels based on propagation measurements","authors":"W. Mohr","doi":"10.1109/PIMRC.1995.480899","DOIUrl":"https://doi.org/10.1109/PIMRC.1995.480899","url":null,"abstract":"Synthetic models of the wideband mobile radio channel are required for mobile radio system design and optimization based on simulations. Additionally wideband models are implemented into hardware channel simulations which approximate the physical radio channel for experimental investigations. These models mainly correspond to a transversal filter structure. They are described by a small set of parameters like tap delays statistics of the tap amplitudes and their corresponding Doppler spectra. Additionally long-term fading and distance dependence can be implemented. For the derivation of such models from a set of wideband measured complex impulse responses a mathematical heuristical approach is presented to determine these model parameters for a given number of taps with constant delays. Every tap is described by its complex time-varying amplitude including its statistic and Doppler spectrum. Additionally long-term fading due to shadowing and distance dependence are taken into account. The procedure yields a reasonable model for a given wideband measured radio channel to approximate the statistical properties of the physical channel.","PeriodicalId":433500,"journal":{"name":"Proceedings of 6th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124545705","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}