Publications (8)0 Total impact
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Book: MIMO: Wireless Communications
01/2008; Citeseer. -
Conference Proceeding: Evaluation of diversity gain and system capacity increase in a multiple HAP system
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ABSTRACT: High altitude platform (HAP) system offers establishment of communication links with predominantly line-of-sight (LOS) conditions due to high elevation angles. However, in mobile scenario, the transmitted signal is still subject to blocking due to obstacles between HAP and the user, which increases the probability of link outage. In the light of this, multiple HAP constellations with overlapped coverage areas can be exploited for platform diversity to improve the system reliability and availability or for the increase of the system capacity through the use of highly directional user antennas. In this paper we evaluate a potential diversity gain and capacity increase for a mobile scenario based on a simulation taking into account a digital relief model (DRM) of Slovenia and two main railway tracks, providing results in terms of the timeshare of different visibility events and the CINR valuesSatellite and Space Communications, 2006 International Workshop on; 10/2006 -
Conference Proceeding: Powerline communication switch
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ABSTRACT: An alternative to cabling of a home or local area was traditionally wireless communication. Because of its drawbacks in security and reliability, in some circumstances, networking can be implemented over existing power distribution lines. The powerline communication technology has matured in the last few years in terms of communication speed and reliability in such an extent that it has become a method of choice in many applications. In this paper an implementation and performance of a low cost powerline communication switch is given.Electronics in Marine, 2004. Proceedings Elmar 2004. 46th International Symposium; 07/2004 -
Conference Proceeding: A recursive link adaptation algorithm for MIMO systems
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ABSTRACT: An algorithm to adjust the coding modulation (CM) scheme in a multiple-input multiple-output (MIMO) wireless communication system is proposed and analyzed. The CM scheme selected for each transmitter is determined by a recursive procedure at the receiver, taking into account estimated signal to noise ratio and the properties of available CM schemes. The performance of the algorithm was tested using pseudo-inverse (PINV) detection algorithm supporting constant BER criteria.Electrotechnical Conference, 2004. MELECON 2004. Proceedings of the 12th IEEE Mediterranean; 06/2004 -
Conference Proceeding: V-BLAST algorithm performance in non-linear channel
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ABSTRACT: High power amplifier impact on the signal power spectrum spreading into neighbouring frequency bands and degradation of the BER system performance due to nonlinear high power amplifier distortions are analysed for 4-QAM and 16-QAM signals in MIMO communication systems, using the V-BLAST algorithm for signal detection. The high power amplifier model is based on measured AM/AM and AM/PM characteristics of a 28GHz solid state power amplifier. The signal power emission in neighbouring frequency bands mostly depends on the peak to average power ratio of the transmitted signal, and it is higher for 16-QAM than for 4-QAM signal. The degradation in BER performance is larger for higher modulation level and higher number of transmit antennas.EUROCON 2003. Computer as a Tool. The IEEE Region 8; 10/2003 -
Conference Proceeding: Dynamic channel mapping strategies in adaptive MIMO systems
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ABSTRACT: A channel mapping strategies and their impact on bit error rate (BER) and on system capacity for multiple-input multiple-output MIMO systems in a quasistatic flat fading channel is analysed. MIMO orthogonal subchannels are split into reliable subchannels, where the target BER can be guaranteed, and unreliable subchannels, where the requirements of target BER cannot be met. The modulation level of M-QAM signal transmitted in a reliable subchannel is dynamically adapted to channel state information. The information is transmitted only in reliable subchannels in the elementary channel mapping strategy, while in advanced channel mapping strategies, one, two or more subchannels are combined to increase the system capacity. The average channel capacity achieved by an elementary mapping strategy does not differ significantly from that for advanced ones for high SNR (signal to noise ratio), while at low and medium SNR only the advanced channel mapping strategies guarantee the target BER in the communication link.Personal, Indoor and Mobile Radio Communications, 2003. PIMRC 2003. 14th IEEE Proceedings on; 10/2003 -
Conference Proceeding: Adaptive data mapping of wavelet compressed images in MIMO systems
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ABSTRACT: The adaptive data mapping of wavelet compressed images in multiple input multiple output (MIMO) wireless communication systems is proposed and analyzed. Image compression methods based on wavelet transform allow image decomposition in blocks, representing signal frequency bands at different resolutions. Blocks representing low frequencies are very important for visual image quality, while the highest frequency blocks, even lost, have almost no impact on image quality. MIMO systems offer parallel subchannels with different quality. Mapping more important data to higher quality subchannels improves the image quality. The results obtained by analog devices wavelet algorithm, implemented in a single chip ADV601, used in the MIMO system with four transmit and four receive antennas, show that the adaptive data mapping approach improves the peak signal to noise ratio (PSNR) up to 8 dB in comparison to standard data mapping.Video/Image Processing and Multimedia Communications, 2003. 4th EURASIP Conference focused on; 08/2003 -
Conference Proceeding: Single-board wavelet video compression/decompression unit
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ABSTRACT: The system described is based on the wavelet video compression/decompression method, implemented on a single board and tailored for real-time work. Different bit-rates are supported in the full-duplex mode and in the range from 8-50 Mbit/s. The specific solution of the internal DMA transfer between the compressor/decompressor and the transmission FIFO buffers is described. Some considerations on the constant bit-rate implementation are given. An example for a live video transmission on an SDH loop is shown.Video/Image Processing and Multimedia Communications 4th EURASIP-IEEE Region 8 International Symposium on VIPromCom; 02/2002
Top co-authors
Institutions
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2003
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Jožef Stefan Institute
- Komunikacijski sistemi
Ljubljana, Ljubljana, Slovenia
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