Pub Date : 1998-09-02DOI: 10.1109/ISSSTA.1998.726196
C. Boulanger, L. Ouvry
This paper presents new binary spreading sequences, obtained by tabu search. These sequences exhibit odd correlation properties concerning the minimax criterion better than those of the classical sequence families, such as the well known Kasami and Gold sequences. In particular, the design process takes into account both odd and even correlation properties which means that global performance is compromised. These new sequences also have same mean-square correlation performance as classical ones.
{"title":"Tabu search: an efficient tool for designing DS-CDMA spreading sequences","authors":"C. Boulanger, L. Ouvry","doi":"10.1109/ISSSTA.1998.726196","DOIUrl":"https://doi.org/10.1109/ISSSTA.1998.726196","url":null,"abstract":"This paper presents new binary spreading sequences, obtained by tabu search. These sequences exhibit odd correlation properties concerning the minimax criterion better than those of the classical sequence families, such as the well known Kasami and Gold sequences. In particular, the design process takes into account both odd and even correlation properties which means that global performance is compromised. These new sequences also have same mean-square correlation performance as classical ones.","PeriodicalId":116377,"journal":{"name":"1988 IEEE 5th International Symposium on Spread Spectrum Techniques and Applications - Proceedings. Spread Technology to Africa (Cat. No.98TH8333)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121260296","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 : 1998-09-02DOI: 10.1109/ISSSTA.1998.723837
J. Kivinen, P. Vainikainen
This paper describes wideband propagation measurements in corridors with 5.3 GHz carrier frequency. Measurements have been performed using a wideband radio channel sounder with 54 MHz 3 dB bandwidth. Over 20000 complex impulse responses have been recorded and analysed with delay resolution of 20 ns and dynamic range of 20 dB. Measurements have been performed with omnidirectional and directive antennas with both vertical and horizontal polarizations. Although directive antennas inherently reduce the average RMS delay spread values, it was found that the largest instantaneous RMS delay spread values were detected using directive antennas. Considerable differences in propagation characteristics of the vertical and horizontal polarization were measured in NLOS conditions. These differences were interpreted to result from the different reflection coefficients of the building structures for the two polarisations. Large scale pathless modeling was done by applying analogy to oversized waveguide structures.
{"title":"Wideband propagation measurements in corridors at 5.3 GHz","authors":"J. Kivinen, P. Vainikainen","doi":"10.1109/ISSSTA.1998.723837","DOIUrl":"https://doi.org/10.1109/ISSSTA.1998.723837","url":null,"abstract":"This paper describes wideband propagation measurements in corridors with 5.3 GHz carrier frequency. Measurements have been performed using a wideband radio channel sounder with 54 MHz 3 dB bandwidth. Over 20000 complex impulse responses have been recorded and analysed with delay resolution of 20 ns and dynamic range of 20 dB. Measurements have been performed with omnidirectional and directive antennas with both vertical and horizontal polarizations. Although directive antennas inherently reduce the average RMS delay spread values, it was found that the largest instantaneous RMS delay spread values were detected using directive antennas. Considerable differences in propagation characteristics of the vertical and horizontal polarization were measured in NLOS conditions. These differences were interpreted to result from the different reflection coefficients of the building structures for the two polarisations. Large scale pathless modeling was done by applying analogy to oversized waveguide structures.","PeriodicalId":116377,"journal":{"name":"1988 IEEE 5th International Symposium on Spread Spectrum Techniques and Applications - Proceedings. Spread Technology to Africa (Cat. No.98TH8333)","volume":"261 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115996604","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 : 1998-09-02DOI: 10.1109/ISSSTA.1998.726199
T. Waldeck, M. Busser, K. Dostert
Using low voltage energy distribution grids as high-speed communication networks opens up the possibility to utilities to establish widespread local area networks for telecommunication services such as telephony and Internet access without the necessity of additional cabling. Since communication systems, suitable for high-speed transmission over electrical power lines, are not available yet, considerable efforts are currently being spent on designing such systems. Due to the special properties of power distribution grids as communication channels, profound investigations of the channel properties must have been done before a successful development of reliable and efficient systems is possible. At the University of Karlsruhe extensive measurements of typical channel properties are currently under way. Some of the results are presented in this work, giving a first impression of the most important channel properties. However, the main goal of this paper is to investigate and describe suitable strategies for advanced multiple access systems.
{"title":"Telecommunication applications over the low voltage power distribution grid","authors":"T. Waldeck, M. Busser, K. Dostert","doi":"10.1109/ISSSTA.1998.726199","DOIUrl":"https://doi.org/10.1109/ISSSTA.1998.726199","url":null,"abstract":"Using low voltage energy distribution grids as high-speed communication networks opens up the possibility to utilities to establish widespread local area networks for telecommunication services such as telephony and Internet access without the necessity of additional cabling. Since communication systems, suitable for high-speed transmission over electrical power lines, are not available yet, considerable efforts are currently being spent on designing such systems. Due to the special properties of power distribution grids as communication channels, profound investigations of the channel properties must have been done before a successful development of reliable and efficient systems is possible. At the University of Karlsruhe extensive measurements of typical channel properties are currently under way. Some of the results are presented in this work, giving a first impression of the most important channel properties. However, the main goal of this paper is to investigate and describe suitable strategies for advanced multiple access systems.","PeriodicalId":116377,"journal":{"name":"1988 IEEE 5th International Symposium on Spread Spectrum Techniques and Applications - Proceedings. Spread Technology to Africa (Cat. No.98TH8333)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129622904","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 : 1998-09-02DOI: 10.1109/ISSSTA.1998.722531
V. Behar, C. Kabakchiev
It is shown that the Hough transform with binary integration of the data in parameter space may be used for improvement of target detection in the presence of strong pulse jamming (PJ). The algorithm proposed may be used for effective detection of small airborne targets whose trajectories are straight radial lines. The expressions for detection probability evaluation are derived for a target model according to the Swerling case II. The expressions obtained are applied to the typical surveillance radar. The results show that the algorithm proposed allows one sufficiently to reduce the losses in the signal-to noise ratio (SNR) in comparison to the CA CFAR detector with non-coherent integration when the PJ intensity is very strong. It is shown that the algorithm proposed is very effective even if the probability of PJ appearance is very high.
{"title":"Hough detector with adaptive non-coherent integration for target detection in pulse jamming","authors":"V. Behar, C. Kabakchiev","doi":"10.1109/ISSSTA.1998.722531","DOIUrl":"https://doi.org/10.1109/ISSSTA.1998.722531","url":null,"abstract":"It is shown that the Hough transform with binary integration of the data in parameter space may be used for improvement of target detection in the presence of strong pulse jamming (PJ). The algorithm proposed may be used for effective detection of small airborne targets whose trajectories are straight radial lines. The expressions for detection probability evaluation are derived for a target model according to the Swerling case II. The expressions obtained are applied to the typical surveillance radar. The results show that the algorithm proposed allows one sufficiently to reduce the losses in the signal-to noise ratio (SNR) in comparison to the CA CFAR detector with non-coherent integration when the PJ intensity is very strong. It is shown that the algorithm proposed is very effective even if the probability of PJ appearance is very high.","PeriodicalId":116377,"journal":{"name":"1988 IEEE 5th International Symposium on Spread Spectrum Techniques and Applications - Proceedings. Spread Technology to Africa (Cat. No.98TH8333)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124563633","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 : 1998-09-02DOI: 10.1109/ISSSTA.1998.723836
T. Imoto, N. Suehiro
Power control or interference cancellation requires a heavy cost for the uplink in mobile CDMA systems. Suehiro (1993, 1994) proposed a 4-phase signal design for approximately synchronized CDMA systems without co-channel interference. In the proposed 4-phase signal design, each user is assigned a carrier frequency, some 4-phase sequence of finite length with pseudo-periodic property and comb-shaped spectrum, and a matched filter for the central large part of the assigned sequence. When the assigned sequence of the comb-shaped spectrum is modulated by the carrier the obtained signal has a comb-shaped spread spectrum. The carriers are assigned to each user so that any two of the users have an orthogonal comb-spectrum to each other. Because each user has a filter which is matched to the central part of the assigned sequence, no user receives co-channel interference near the main detection pulse under the condition of approximate synchronization. The Doppler effect and the multipath properties are simulated. When the carrier frequencies are about 2000 MHz, the signals works almost without co-channel interference under the Doppler shift at 1000 km/h. This result of simulation shows the usefulness of the 4-phase signal design without co-channel interference for an approximately synchronized uplink in cellular CDMA systems.
{"title":"Doppler and multipath properties of quadriphase signal design without co-channel interference nor detection sidelobe for uplink in approximately synchronized cellular CDMA systems","authors":"T. Imoto, N. Suehiro","doi":"10.1109/ISSSTA.1998.723836","DOIUrl":"https://doi.org/10.1109/ISSSTA.1998.723836","url":null,"abstract":"Power control or interference cancellation requires a heavy cost for the uplink in mobile CDMA systems. Suehiro (1993, 1994) proposed a 4-phase signal design for approximately synchronized CDMA systems without co-channel interference. In the proposed 4-phase signal design, each user is assigned a carrier frequency, some 4-phase sequence of finite length with pseudo-periodic property and comb-shaped spectrum, and a matched filter for the central large part of the assigned sequence. When the assigned sequence of the comb-shaped spectrum is modulated by the carrier the obtained signal has a comb-shaped spread spectrum. The carriers are assigned to each user so that any two of the users have an orthogonal comb-spectrum to each other. Because each user has a filter which is matched to the central part of the assigned sequence, no user receives co-channel interference near the main detection pulse under the condition of approximate synchronization. The Doppler effect and the multipath properties are simulated. When the carrier frequencies are about 2000 MHz, the signals works almost without co-channel interference under the Doppler shift at 1000 km/h. This result of simulation shows the usefulness of the 4-phase signal design without co-channel interference for an approximately synchronized uplink in cellular CDMA systems.","PeriodicalId":116377,"journal":{"name":"1988 IEEE 5th International Symposium on Spread Spectrum Techniques and Applications - Proceedings. Spread Technology to Africa (Cat. No.98TH8333)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129096228","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 : 1998-09-02DOI: 10.1109/ISSSTA.1998.726206
P. Grant, S. M. Spangenberg, I. Scott, S. Mclaughlin, G. Povey, D. Cruickshank
This paper describes a non-coherent technique which employs a fast Fourier transform (FFT) for the fast acquisition of direct sequence spread spectrum signals in the presence of large Doppler shifts. The application of an FFT to code acquisition results in decreased acquisition time and can improve the probability of detection. The technique discussed in this paper uses a set of partial correlators and a zero-padded FFT to reduce the search region for code acquisition whilst maintaining good frequency resolution for Doppler offset. This approach will prove most pertinent in future re-configurable terminals.
{"title":"Doppler estimation for fast acquisition in spread spectrum communication systems","authors":"P. Grant, S. M. Spangenberg, I. Scott, S. Mclaughlin, G. Povey, D. Cruickshank","doi":"10.1109/ISSSTA.1998.726206","DOIUrl":"https://doi.org/10.1109/ISSSTA.1998.726206","url":null,"abstract":"This paper describes a non-coherent technique which employs a fast Fourier transform (FFT) for the fast acquisition of direct sequence spread spectrum signals in the presence of large Doppler shifts. The application of an FFT to code acquisition results in decreased acquisition time and can improve the probability of detection. The technique discussed in this paper uses a set of partial correlators and a zero-padded FFT to reduce the search region for code acquisition whilst maintaining good frequency resolution for Doppler offset. This approach will prove most pertinent in future re-configurable terminals.","PeriodicalId":116377,"journal":{"name":"1988 IEEE 5th International Symposium on Spread Spectrum Techniques and Applications - Proceedings. Spread Technology to Africa (Cat. No.98TH8333)","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123978085","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 : 1998-09-02DOI: 10.1109/ISSSTA.1998.723865
B. Steiner, R. Valentin
The problem of MIMO (multiple input multiple output) uplink channel estimation in MC/JD-CDMA (multi-carrier joint detection code division multiple access) systems is dealt with. Two different estimation approaches are proposed. The first approach is capable of directly estimating the desired samples of the so-called combined impulse response while the second approach relies on the well-known concept of estimating the samples on an unknown channel impulse response. In the course of the paper, the two approaches are discussed indicating both their advantages and drawbacks. Finally, simulation results are presented to facilitate a comparison of two approaches using a realistic channel model.
{"title":"A comparison of uplink channel estimation techniques for MC/JD-CDMA transmission systems","authors":"B. Steiner, R. Valentin","doi":"10.1109/ISSSTA.1998.723865","DOIUrl":"https://doi.org/10.1109/ISSSTA.1998.723865","url":null,"abstract":"The problem of MIMO (multiple input multiple output) uplink channel estimation in MC/JD-CDMA (multi-carrier joint detection code division multiple access) systems is dealt with. Two different estimation approaches are proposed. The first approach is capable of directly estimating the desired samples of the so-called combined impulse response while the second approach relies on the well-known concept of estimating the samples on an unknown channel impulse response. In the course of the paper, the two approaches are discussed indicating both their advantages and drawbacks. Finally, simulation results are presented to facilitate a comparison of two approaches using a realistic channel model.","PeriodicalId":116377,"journal":{"name":"1988 IEEE 5th International Symposium on Spread Spectrum Techniques and Applications - Proceedings. Spread Technology to Africa (Cat. No.98TH8333)","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114635299","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 : 1998-09-02DOI: 10.1109/ISSSTA.1998.722530
A. Petrovic, A. Zejak, B. Zrnic, I. Simic
A new approach is proposed to envelope constrained filter (ECF) design. The new approach utilizes the minimax algorithms, originally developed for sidelobe suppression in radar applications. The new approach has been compared to the conventional approach, which utilizes the tools of nonlinear programming. The comparative analysis shows that the new approach promises a better performance in the nonfeasible solution scenario.
{"title":"Minimax algorithm application in ECF and ECUI design","authors":"A. Petrovic, A. Zejak, B. Zrnic, I. Simic","doi":"10.1109/ISSSTA.1998.722530","DOIUrl":"https://doi.org/10.1109/ISSSTA.1998.722530","url":null,"abstract":"A new approach is proposed to envelope constrained filter (ECF) design. The new approach utilizes the minimax algorithms, originally developed for sidelobe suppression in radar applications. The new approach has been compared to the conventional approach, which utilizes the tools of nonlinear programming. The comparative analysis shows that the new approach promises a better performance in the nonfeasible solution scenario.","PeriodicalId":116377,"journal":{"name":"1988 IEEE 5th International Symposium on Spread Spectrum Techniques and Applications - Proceedings. Spread Technology to Africa (Cat. No.98TH8333)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114846014","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 : 1998-09-02DOI: 10.1109/ISSSTA.1998.723854
M. Eric, S. Parkvall, M. Dukic, M. Obradovic
A subspace based MUSIC type algorithm for joint direction of arrival (DOA), time-delay and frequency-shift estimation in asynchronous DS CDMA systems, which is based on spatio-temporal processing of signals received by an antenna array of generally non-uniform volume geometry is proposed. The proposed algorithm is near-far resistant, requires no preamble, and can be applied when orthogonality conditions is not perfectly satisfied. The algorithm can be used for both single user and multi-user estimation.
{"title":"An algorithm for joint direction of arrival, time-delay and frequency-shift estimation in asynchronous DS-CDMA systems","authors":"M. Eric, S. Parkvall, M. Dukic, M. Obradovic","doi":"10.1109/ISSSTA.1998.723854","DOIUrl":"https://doi.org/10.1109/ISSSTA.1998.723854","url":null,"abstract":"A subspace based MUSIC type algorithm for joint direction of arrival (DOA), time-delay and frequency-shift estimation in asynchronous DS CDMA systems, which is based on spatio-temporal processing of signals received by an antenna array of generally non-uniform volume geometry is proposed. The proposed algorithm is near-far resistant, requires no preamble, and can be applied when orthogonality conditions is not perfectly satisfied. The algorithm can be used for both single user and multi-user estimation.","PeriodicalId":116377,"journal":{"name":"1988 IEEE 5th International Symposium on Spread Spectrum Techniques and Applications - Proceedings. Spread Technology to Africa (Cat. No.98TH8333)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124100704","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 : 1998-09-02DOI: 10.1109/ISSSTA.1998.722510
H. Shalaby
A chip-level detector for optical overlapping pulse-position modulation code-division multiple-access (OPPM-CDMA) communication systems is proposed. The bit error rate of the proposed system is derived and compared to some traditional receivers under the constraints of fixed data rate and laser pulsewidth. These traditional receivers include OOK-, PPM-, and OPPM-CDMA correlators. The throughput limitations of all these receivers are also presented and compared. Our results reveal that a significant improvement in the performance is gained when using the proposed scheme. A throughput limitation of about 7.5 times greater than that of OOK-CDMA correlator is reported on the average.
{"title":"Chip-level receivers in optical overlapping PPM-CDMA","authors":"H. Shalaby","doi":"10.1109/ISSSTA.1998.722510","DOIUrl":"https://doi.org/10.1109/ISSSTA.1998.722510","url":null,"abstract":"A chip-level detector for optical overlapping pulse-position modulation code-division multiple-access (OPPM-CDMA) communication systems is proposed. The bit error rate of the proposed system is derived and compared to some traditional receivers under the constraints of fixed data rate and laser pulsewidth. These traditional receivers include OOK-, PPM-, and OPPM-CDMA correlators. The throughput limitations of all these receivers are also presented and compared. Our results reveal that a significant improvement in the performance is gained when using the proposed scheme. A throughput limitation of about 7.5 times greater than that of OOK-CDMA correlator is reported on the average.","PeriodicalId":116377,"journal":{"name":"1988 IEEE 5th International Symposium on Spread Spectrum Techniques and Applications - Proceedings. Spread Technology to Africa (Cat. No.98TH8333)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128046031","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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