- Trípolis, Arcadia, Greece
The paper presents results for the likely capacity improvement when an adaptive multibeam antenna is used in conjunction with air interface parameters akin to the DCS1800 system. The analysis investigates the possible capacity enhancement... more
The paper presents results for the likely capacity improvement when an adaptive multibeam antenna is used in conjunction with air interface parameters akin to the DCS1800 system. The analysis investigates the possible capacity enhancement whilst taking into account parameters such as power control, number of available handover channels, radiation pattern, radio channel characteristics and different frequency reuse patterns. The results
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Scope of this paper is to analyse four subcarrier allocation algorithms for multicellular OFDMA networks, namely coordinated, sequential, random and an innovative technique of cell splitting, that uses both random and coordinated... more
Scope of this paper is to analyse four subcarrier allocation algorithms for multicellular OFDMA networks, namely coordinated, sequential, random and an innovative technique of cell splitting, that uses both random and coordinated subcarrier allocation. Common characteristic of these subcarrier allocation algorithms is that they do not require knowledge of channel state information (CSI) at the transmitter, a fact that leads to more efficient use of available bandwidth, lower algorithmic complexity and faster decision making. The algorithms are studied for an OFDMA multicellular network. Simulation results show that a multicellular OFDMA network is able to provide real broadband wireless access, with offered bit rate to reach 20 Mbps per cell, even without CSI knowledge.
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Adaptive antennas are among the favourite techniques to help the current systems evolve towards third generation mobile communication systems. However, among the major concerns for adaptive antenna systems are the calibration process and... more
Adaptive antennas are among the favourite techniques to help the current systems evolve towards third generation mobile communication systems. However, among the major concerns for adaptive antenna systems are the calibration process and the non-linearity effects of the RF-IF chains upon the performance of the beamforming network. This article investigates these issues based on experimental results produced with the adaptive
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This paper considers the performance of a DS-CDMA system which employs adaptive antenna technology at the basestation site. By utilising the capability of ray-tracing to provide the complex channel impulse response, a new ray-based... more
This paper considers the performance of a DS-CDMA system which employs adaptive antenna technology at the basestation site. By utilising the capability of ray-tracing to provide the complex channel impulse response, a new ray-based simulation methodology for an adaptive antenna in a DS-CDMA system is presented. Results for a typical microcellular environment highlight the behaviour of the adaptive antenna. Finally,
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... George V. Tsoulos, Mark A. Beach, Simon C. Swales ... one user, and the error signal is defmed as the difference between the array output and the desired signal e(k) y(k)- roCk). ... [12] Array Signal Processing: Concepts and... more
... George V. Tsoulos, Mark A. Beach, Simon C. Swales ... one user, and the error signal is defmed as the difference between the array output and the desired signal e(k) y(k)- roCk). ... [12] Array Signal Processing: Concepts and Techniques, DHJohnson and DEDudgeon, Prentice ...
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... This paper will present an overview of the proposed mixed cell architecture employing adaptive antenna technology at the Umbrella cell ... 1.C.Symington & E.Green. ... JPMc-G.Norton, "Rake decorrelation BS an... more
... This paper will present an overview of the proposed mixed cell architecture employing adaptive antenna technology at the Umbrella cell ... 1.C.Symington & E.Green. ... JPMc-G.Norton, "Rake decorrelation BS an alternative to rapid powex control in DS-CDMA mobile radio", IEEE ...
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This paper considers the performance of a DS-CDMA system which employs adaptive antenna technology at the base station site of a microcell. By utilising the capability of ray-tracing to provide the complex channel impulse response, a new... more
This paper considers the performance of a DS-CDMA system which employs adaptive antenna technology at the base station site of a microcell. By utilising the capability of ray-tracing to provide the complex channel impulse response, a new ray-based simulation methodology for an adaptive antenna in a DS-CDMA system is presented. Results for a typical microcellular environment highlight the behaviour of the adaptive antenna. Finally, with the help of a Monte-Carlo type DS-CDMA capacity analysis, the potential performance enhancement and the sensitivity of the system upon the misspointing of the main beam, are evaluated
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... algorithms for voice loaded system [47] method (FM) shows slightly worse performance than the ... The analysis also showed that although the fixed beam approaches can give acceptable ... environments, the antenna array gain can be... more
... algorithms for voice loaded system [47] method (FM) shows slightly worse performance than the ... The analysis also showed that although the fixed beam approaches can give acceptable ... environments, the antenna array gain can be exchanged for signal quality enhancement, ie ...
... While great effort in current (second) generation wireless communication systems has been directed towards the development of modulation, coding and protocols ...
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Spatial filtering for mobile communications has attracted a lot of attention over the last decade and is currently considered a very promising technique that will help future cellular networks achieve their ambitious goals. One way to... more
Spatial filtering for mobile communications has attracted a lot of attention over the last decade and is currently considered a very promising technique that will help future cellular networks achieve their ambitious goals. One way to accomplish this is via array signal processing with algorithms which estimate the direction-of-arrival (DOA) of the received waves from the mobile users. This paper
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Page 1. PART III ARRAYS AND SYNTHESIS METHODS 529 Page 2. CHAPTER 11 Arrays and Smart Antennas GEORGE V. TSOULOS and CHRISTOS G. CHRISTODOULOU 11.1 INTRODUCTION Over the last decade the ...
... Channel Data 175 Quentin H. Spencer, Jon W. Wallace, Christian B. Peel, Thomas Svantesson, A. Lee Swindlehurst, Harry Lee, and Ajay Gumalla 8 Multiuser MIMO for UTRA FDD 207 Jyri Hcimdlciinen, Risto Wichman, Markku Kuusela, Esa... more
... Channel Data 175 Quentin H. Spencer, Jon W. Wallace, Christian B. Peel, Thomas Svantesson, A. Lee Swindlehurst, Harry Lee, and Ajay Gumalla 8 Multiuser MIMO for UTRA FDD 207 Jyri Hcimdlciinen, Risto Wichman, Markku Kuusela, Esa Tiirola, and Kari Pajukoski 9 ...
ABSTRACT Optimum basestation positioning in the framework of LTE wireless networks is not an easy task since there are several factors that need to be taken into account. The ever increasing demand for geographically inhomogeneous... more
ABSTRACT Optimum basestation positioning in the framework of LTE wireless networks is not an easy task since there are several factors that need to be taken into account. The ever increasing demand for geographically inhomogeneous capacity, which has become the limiting factor in the network planning process, as well as the presence of relay nodes and ixed cell scenarios, must all now be considered along with the system’s constraints and capabilities. In this paper, the optimization problem for an LTE system is described and results are produced with a proposed partially combinatorial optimization algorithm. The optimization analysis is based on coverage, capacity and cost criteria. Example results are provided for a typical case study that give useful planning insights for LTE systems.
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... IEEE Ttrans. On Commun., Vol. 48, No. 3, March 2000, pp. 502-512 [3] Arogyaswami Paulraj, Rohit Nabar and Dhanan-jay Gore, Introduction to Space-Time Wireless Communications,Cambridge University Press, 2003 [4 ...
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This paper considers the performance of a DS-CDMA system employing adaptive antenna technology at the base station site for both an umbrella and a micro-cell in a hierarchical cell structure. The possible advantages and problems from such... more
This paper considers the performance of a DS-CDMA system employing adaptive antenna technology at the base station site for both an umbrella and a micro-cell in a hierarchical cell structure. The possible advantages and problems from such deployment are discussed. By exploiting the capabilities of ray tracing to provide the complex channel impulse response, a new adaptive antenna simulation model
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ABSTRACT
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The issue of UMTS WCDMA radio network planning with smart antennas is presented in this paper. First the complexity of 3G network planning is discussed in the context of 2G and smart antennas. Then the impact that smart antennas can have... more
The issue of UMTS WCDMA radio network planning with smart antennas is presented in this paper. First the complexity of 3G network planning is discussed in the context of 2G and smart antennas. Then the impact that smart antennas can have on key WCDMA network parameters, such as capacity and coverage probability is demonstrated with the help of a radio
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... systems, at a fraction of the complexity and expense [3]. The switched beam system requires only a beam-forming network, an RF switch and ... [4] Laiho J., Wacker A., Novosad T., Radio Network planning and Optimisation for UMTS ...... more
... systems, at a fraction of the complexity and expense [3]. The switched beam system requires only a beam-forming network, an RF switch and ... [4] Laiho J., Wacker A., Novosad T., Radio Network planning and Optimisation for UMTS ... [5] Holma H., Toskala A., WCDMA for UMTS ...