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Stefan Lindenmeier - One of the best experts on this subject based on the ideXlab platform.

  • Automotive Antenna Diversity system for satellite radio with high phase accuracy in low SNR-scenarios
    International Journal of Microwave and Wireless Technologies, 2018
    Co-Authors: S. Senega, A. Nassar, Stefan Lindenmeier
    Abstract:

    AbstractFor a fast scan-phase satellite radio Antenna Diversity system a noise correction method is presented for a significant improvement of audio availability at low signal-to-noise ratio (SNR) conditions. An error analysis of the level and phase detection within the Diversity system in the presence of noise leads to a correction method based on a priori knowledge of the system's noise floor. This method is described and applied in a hardware example of a satellite digital audio radio services Antenna Diversity circuit for fast fading conditions. Test drives, which have been performed in real fading scenarios, are described and results are analyzed statistically. Simulations of the scan-phase Antenna Diversity system show higher signal amplitudes and availabilities. Measurement results of dislocated Antennas as well as of a Diversity Antenna set on a single mounting position are presented. A comparison of a Diversity system with noise correction, the same system without noise correction, and a single Antenna system with each other is performed. Using this new method in fast multipath fading driving scenarios underneath dense foliage with a low SNR of the Antenna signals, a reduction in audio mute time by one order of magnitude compared with single Antenna systems is achieved with the Diversity system.

  • New Compact Antenna Diversity with a Fully Integrated Microwave Circuit for Automotive Satellite Radio Reception
    2018 13th European Microwave Integrated Circuits Conference (EuMIC), 2018
    Co-Authors: S. Senega, A. Nassar, Robert Weigel, Jvrgen Rober, Christian Heuert, Stefan Lindenmeier
    Abstract:

    A compact Antenna Diversity system with a new integrated circuit is presented for automotive reception of satellite digital audio radio services (SDARS) at 2.3 GHz. For a scan-phase Antenna Diversity with switching and phase alignment of up to three Antenna paths, the integrated circuit includes RF switches, phase-alignment and signal combining as well as the frequency conversion for level detection. This is the first integrated circuit for SDARS scan-phase Antenna Diversity, which includes all the Diversity functions except for level detection and digital signal processing. With the integrated circuit with a package size of only 9 mm by 9 mm a compact hardware demonstrator is realized. The Diversity circuit is independent of the radio and offers the same interface to the radio as a conventional single Antenna. In laboratory measurements characteristic values of the RF signal paths like gain and variable phase shift are determined. In addition, the new compact Diversity circuit is also evaluated in a real fading scenario on a single side mirror of the test vehicle showing a significant reduction of audio mutes by the Diversity system compared to single Antenna reception.

  • Characterization of a new integrated scan-phase Antenna Diversity circuit for automotive satellite radio reception
    2016 46th European Microwave Conference (EuMC), 2016
    Co-Authors: S. Senega, Juergen Roeber, A. Nassar, Robert Weigel, Christian Heuer, Stefan Lindenmeier
    Abstract:

    An integrated Antenna Diversity system is described which enables a high increase of reception performance for satellite digital audio radio services (SDARS). A detailed analysis is given for the gain and noise figure requirements specifically regarding the implementation in an integrated circuit. On base of this analysis a hardware demonstrator of the scan-phase Antenna Diversity system is realized in which the phase aligned rf combining and signal selection is implemented completely in a compact IC with a package size of only 8 mm by 8 mm. For evaluation the integrated scan-phase Antenna Diversity system is fed by different Antenna signals of real test drives in the US. The Diversity system proves its functionality in reducing the overall time of audio mutes by almost one order in magnitude compared to standard single Antennas.

  • Antenna module with integrated scan-phase Antenna Diversity system for SDARS
    2012 6th European Conference on Antennas and Propagation (EUCAP), 2012
    Co-Authors: S. Senega, Stefan Lindenmeier
    Abstract:

    A scan-phase multi-Antenna Diversity system is able to significantly improve reception performance of satellite digital audio radio systems (SDARS) in severe multipath propagation scenarios. The low hardware cost of such a system can only be achieved if a single level measurement circuitry is used for all Antenna signals. In this paper the influences of switching between the Antenna signals for level detection and the signal processing in the Diversity system are studied for two different Antenna Diversity systems. A modification of the Diversity hardware that avoids those influences is investigated. Measurements were performed to compare the modified and unmodified system in terms of audio availability. Test drives underneath dense foliage were conducted with a scan-phase Antenna Diversity system in combination with a Diversity Antenna set mounted on the dashboard of a car. This mounting position is of wide interest for example for convertibles, where the car roof is not available for the mounting of SDARS Antennas. Measurement results show that the scan-phase Antenna Diversity system performs very well in such a disadvantageous Antenna position. The Diversity combination on the dashboard can compete with a roof-mounted patch Antenna in the reception of geostationary satellite signals even with a closed roof.

  • Comparison of automotive FM Antenna Diversity concepts with a compound reception test system
    2012 6th European Conference on Antennas and Propagation (EUCAP), 2012
    Co-Authors: S. Treinies, J. Hopf, Stefan Lindenmeier
    Abstract:

    In the automotive industry, reliable and reproducible test methods are required for the evaluation of car Antennas and Antenna Diversity systems. This is accomplished by a new compound advanced system analysis method which enables analysis of complete reception systems. In this new test method real recorded or alternatively simulated RF Antenna signals are fed into the reception system and a compound automatic signal analysis is performed on base of its audio behavior. In this paper test results are shown by example of FM reception systems equipped with different Antenna Diversity concepts in comparison with each other. The results are confirmed by a set of additional subjective blind listening tests for different audio contents. Aspects are analyzed which influence the impression of reception quality.

S. Senega - One of the best experts on this subject based on the ideXlab platform.

  • Automotive Antenna Diversity system for satellite radio with high phase accuracy in low SNR-scenarios
    International Journal of Microwave and Wireless Technologies, 2018
    Co-Authors: S. Senega, A. Nassar, Stefan Lindenmeier
    Abstract:

    AbstractFor a fast scan-phase satellite radio Antenna Diversity system a noise correction method is presented for a significant improvement of audio availability at low signal-to-noise ratio (SNR) conditions. An error analysis of the level and phase detection within the Diversity system in the presence of noise leads to a correction method based on a priori knowledge of the system's noise floor. This method is described and applied in a hardware example of a satellite digital audio radio services Antenna Diversity circuit for fast fading conditions. Test drives, which have been performed in real fading scenarios, are described and results are analyzed statistically. Simulations of the scan-phase Antenna Diversity system show higher signal amplitudes and availabilities. Measurement results of dislocated Antennas as well as of a Diversity Antenna set on a single mounting position are presented. A comparison of a Diversity system with noise correction, the same system without noise correction, and a single Antenna system with each other is performed. Using this new method in fast multipath fading driving scenarios underneath dense foliage with a low SNR of the Antenna signals, a reduction in audio mute time by one order of magnitude compared with single Antenna systems is achieved with the Diversity system.

  • New Compact Antenna Diversity with a Fully Integrated Microwave Circuit for Automotive Satellite Radio Reception
    2018 13th European Microwave Integrated Circuits Conference (EuMIC), 2018
    Co-Authors: S. Senega, A. Nassar, Robert Weigel, Jvrgen Rober, Christian Heuert, Stefan Lindenmeier
    Abstract:

    A compact Antenna Diversity system with a new integrated circuit is presented for automotive reception of satellite digital audio radio services (SDARS) at 2.3 GHz. For a scan-phase Antenna Diversity with switching and phase alignment of up to three Antenna paths, the integrated circuit includes RF switches, phase-alignment and signal combining as well as the frequency conversion for level detection. This is the first integrated circuit for SDARS scan-phase Antenna Diversity, which includes all the Diversity functions except for level detection and digital signal processing. With the integrated circuit with a package size of only 9 mm by 9 mm a compact hardware demonstrator is realized. The Diversity circuit is independent of the radio and offers the same interface to the radio as a conventional single Antenna. In laboratory measurements characteristic values of the RF signal paths like gain and variable phase shift are determined. In addition, the new compact Diversity circuit is also evaluated in a real fading scenario on a single side mirror of the test vehicle showing a significant reduction of audio mutes by the Diversity system compared to single Antenna reception.

  • Characterization of a new integrated scan-phase Antenna Diversity circuit for automotive satellite radio reception
    2016 46th European Microwave Conference (EuMC), 2016
    Co-Authors: S. Senega, Juergen Roeber, A. Nassar, Robert Weigel, Christian Heuer, Stefan Lindenmeier
    Abstract:

    An integrated Antenna Diversity system is described which enables a high increase of reception performance for satellite digital audio radio services (SDARS). A detailed analysis is given for the gain and noise figure requirements specifically regarding the implementation in an integrated circuit. On base of this analysis a hardware demonstrator of the scan-phase Antenna Diversity system is realized in which the phase aligned rf combining and signal selection is implemented completely in a compact IC with a package size of only 8 mm by 8 mm. For evaluation the integrated scan-phase Antenna Diversity system is fed by different Antenna signals of real test drives in the US. The Diversity system proves its functionality in reducing the overall time of audio mutes by almost one order in magnitude compared to standard single Antennas.

  • Antenna module with integrated scan-phase Antenna Diversity system for SDARS
    2012 6th European Conference on Antennas and Propagation (EUCAP), 2012
    Co-Authors: S. Senega, Stefan Lindenmeier
    Abstract:

    A scan-phase multi-Antenna Diversity system is able to significantly improve reception performance of satellite digital audio radio systems (SDARS) in severe multipath propagation scenarios. The low hardware cost of such a system can only be achieved if a single level measurement circuitry is used for all Antenna signals. In this paper the influences of switching between the Antenna signals for level detection and the signal processing in the Diversity system are studied for two different Antenna Diversity systems. A modification of the Diversity hardware that avoids those influences is investigated. Measurements were performed to compare the modified and unmodified system in terms of audio availability. Test drives underneath dense foliage were conducted with a scan-phase Antenna Diversity system in combination with a Diversity Antenna set mounted on the dashboard of a car. This mounting position is of wide interest for example for convertibles, where the car roof is not available for the mounting of SDARS Antennas. Measurement results show that the scan-phase Antenna Diversity system performs very well in such a disadvantageous Antenna position. The Diversity combination on the dashboard can compete with a roof-mounted patch Antenna in the reception of geostationary satellite signals even with a closed roof.

  • A fast switching Antenna Diversity system for improved mobile reception of digital radio signals of a geostationary satellite
    2011
    Co-Authors: S. Senega, Stefan Lindenmeier
    Abstract:

    In severe multipath propagation scenarios - as for example underneath dense foliage or between buildings - the mobile reception of satellite digital audio radio services (SDARS) can be severely impaired. Antenna Diversity is able to increase reception in such scenarios and to increase the link margin of satellite signal transmission. In this contribution a scan-phase Antenna Diversity system is shown which can be realised with low hardware effort, using only one RF cable between the Antenna module and the radio. For radio services where the receivers are already fixed, the Antenna Diversity system is arranged in a way, that the Diversity function is performed completely inside the Antenna module. For radio services where the radio can be modified, parts of the Diversity function can be integrated into the digital signal processing unit of the radio. The two versions of scan-phase Diversity are discussed and investigated for the test case of signals which are transmitted from a geostationary satellite. Also a comparison between two different phase shifter resolutions is done in real scenario test drives. Measurement results show that a significant improvement of reception quality is achieved reducing audio mutes by a factor of 20.

Fumiyuki Adachi - One of the best experts on this subject based on the ideXlab platform.

  • VTC Fall - A Novel Analog Signal Transmission Using Joint Space-Time Transmit Diversity and Receive Antenna Diversity
    2014 IEEE 80th Vehicular Technology Conference (VTC2014-Fall), 2014
    Co-Authors: Shinya Kumagai, Fumiyuki Adachi
    Abstract:

    ‡ Abstract—Recently, we proposed a novel analog signal transmission technique called analog single-carrier transmission with frequency-domain equalization (analog SC-FDE) and showed that analog SC-FDE achieves better normalized mean square error (NMSE) performance than conventional analog signal transmission. In order to achieve further performance improvement, transmit/receive Antenna Diversity technique is effective. In digital wireless communications, joint space-time transmit Diversity (STTD) and receive Antenna Diversity is well known as a promising Antenna Diversity technique which achieves a high Diversity order (equal to the product of the number of transmit Antennas and the number of receive Antennas) with a simple signal processing. In this paper, analog SC-FDE using joint STTD and receive Antenna Diversity is proposed. A theoretical analysis of the NMSE performance is derived to evaluate the transmission performance of the proposed scheme and is confirmed by computer simulation. We show that joint STTD and receive Antenna Diversity can significantly improve the NMSE performance of our proposed analog SC- FDE.

  • SINGLE-CARRIER TRANSMISSION USING QRM-MLD WITH Antenna Diversity
    2009
    Co-Authors: Tetsuya Yamamoto Kazuki Takeda, Fumiyuki Adachi
    Abstract:

    The frequency-domain received single-carrier (SC) signal can be expressed using the matrix representation similar to the multiple-input multiple-output (MIMO) multiplexing. The signal detection schemes developed for MIMO multiplexing can be applied to the SC transmissions. In this paper, we apply maximum likelihood detection employing QR decomposition and M-algorithm (QRM-MLD) to the SC signal detection with Antenna Diversity reception. We show that by using Antenna Diversity reception, the number of surviving symbol candidates can be reduced. We evaluate, by the computer simulation, the bit error rate (BER) performance achievable by QRM-MLD and compare it with that achievable by the Vertical-Bell Laboratories Layered spacetime architecture (V-BLAST) detection.

  • joint frequency domain equalization and Antenna Diversity combining for orthogonal multicode ds cdma signal transmissions in a frequency selective fading channel
    IEICE Transactions on Communications, 2004
    Co-Authors: T Itagaki, Fumiyuki Adachi
    Abstract:

    Orthogonal multicode direct sequence code division multiple access (DS-CDMA) has the flexibility in offering various data rate services. However, in a frequency-selective fading channel, the bit error rate (BER) performance is severely degraded since the othogonality among spreading codes is partially lost. In this paper, we apply frequency-domain equalization and Antenna Diversity combining, used in multi-carrier CDMA (MC-CDMA), to orthogonal multicode DS-CDMA in order to restore the code othogonality while achieving frequency and Antenna Diversity effect. It is found by computer simulations that the joint use of frequency-domain equalization and Antenna Diversity combining can significantly improve the BER performance of orthogonal multicode DS-CDMA in a frequencyselective fading channel. key words: frequency-domain equalization, Antenna Diversity, multicode DS-CDMA, frequency-selective fading

  • joint Antenna Diversity and frequency domain equalization for multi rate mc cdma
    IEICE Transactions on Communications, 2003
    Co-Authors: Fumiyuki Adachi
    Abstract:

    SUMMARY For the reception of MC-CDMA signals in a frequency-selective fading channel, frequency-domain equalization is necessary before despreading. In this paper, joint Antenna Diversity combining and one-tap frequency-domain equalization is considered (simply referred to as the joint Antenna Diversity & equalization, in this paper). A receiver structure for joint Antenna Diversity & equalization is presented and the unified weights based on minimum mean square error (MMSE) criterion are found in the presence of multi-users with different spreading factors and transmit powers. For comparison, Antenna Diversity combining after despreading using MMSE combining (MMSEC) is also considered. The achievable bit error rate (BER) performances with joint Antenna Diversity & equalization and with Antenna Diversity after MMSEC despreading in a frequencyselective Rayleigh fading channel are evaluated by computer simulations and compared.

  • Joint effect of transmit power control and Antenna Diversity on spectrum efficiency of a cellular system
    IEICE Transactions on Communications, 2002
    Co-Authors: Fumiyuki Adachi, Akihito Katoh, Deepshikha Garg
    Abstract:

    SUMMARY This paper addresses a classic question about whether transmit power control (TPC) can increase the spectrum efficiency of a TDMA system and an FDMA cellular system as in the case of a DS-CDMA cellular system. Two types of TPC schemes are considered; one is slow TPC that regulates the distance dependent path loss and shadowing loss, while the other is fast TPC that regulates multipath fading as well as path loss and shadowing loss. In addition to TPC, Antenna Diversity reception is considered. The allowable interference rise factor χ, which is defined as the interference plus background noise-to-background noise power ratio, is introduced. The simple expressions for the signal-to-interference plus background noise power ratio (SINR) at the Diversity combiner output using maximal-ratio combining (MRC) are derived to obtain the reuse distance by computer simulations. The impact of joint use of TPC and Antenna Diversity reception on the spectrum efficiency is discussed. It is found that the joint use of fast TPC and Antenna Diversity is advantageous and larger spectrum efficiency can be achieved than with no TPC. On the other hand, the use of slow TPC is found advantageous only for small values of standard deviation of shadowing loss; however, the improvement in the spectrum efficiency is quite small.

Branimir R. Vojcic - One of the best experts on this subject based on the ideXlab platform.

  • TRANSMIT-RECEIVE Antenna Diversity AND TURBO MULTIUSER DETECTION Invited Paper
    2001
    Co-Authors: J. Damnjanovic, Branimir R. Vojcic
    Abstract:

    Antenna Diversity and turbo multiuser detection are two promising techniques for combating channel impairments and multipleaccess interference. In this paper, we propose a novel scheme for a turbo coded system with both transmit and receive Antenna Diversity that employs iterative multiuser detection and decoding. Multiuser detection is embedded into single-user turbo decoding. After each turbo decoding iteration, the extrinsic information of the interfering users is passed to the multiuser detector, and after each multiuser iteration, updated a posteriori probabilities are passed to the singleuser turbo decoders as the soft input metrics. The proposed scheme achieves excellent performance, about 1:8 [dB] away from multiuser capacity for multiple Antennas. It is shown that depending on the channel char

  • Transmit-receive Antenna Diversity and turbo multiuser detection
    2001 MILCOM Proceedings Communications for Network-Centric Operations: Creating the Information Force (Cat. No.01CH37277), 1
    Co-Authors: J. Damnjanovic, Branimir R. Vojcic
    Abstract:

    Antenna Diversity and turbo multiuser detection are two promising techniques for combating channel impairments and multiple-access interference. In this paper, we propose a novel scheme for a turbo coded system with both transmit and receive Antenna Diversity that employs iterative multiuser detection and decoding. Multiuser detection is embedded into single-user turbo decoding. After each turbo decoding iteration, the extrinsic information of the interfering users is passed to the multiuser detector, and after each multiuser iteration, updated a posteriori probabilities are passed to the single-user turbo decoders as the soft input metrics. The proposed scheme achieves excellent performance, about 1.8 [dB] away from multiuser capacity for multiple Antennas. It is shown that depending on the channel characteristics, for a fixed spectral efficiency, that is for a fixed number of virtual users K/sub v/=KT/sub x/, there exists a trade-off between the number of active users K and the number of transmit Antennas T/sub x/.

Mark D. Rice - One of the best experts on this subject based on the ideXlab platform.

  • Indoor measurement of handset dual-Antenna Diversity performance
    Vehicular Technology Conference 1997 IEEE 47th, 1997
    Co-Authors: Marie Lefevre, M.a. Jensen, Mark D. Rice
    Abstract:

    In indoor wireless communications systems, the multipath channel has a significant impact on system design and performance. Antenna Diversity is one approach to overcoming the detrimental fading caused by this multipath phenomenon. This paper presents measured performance of three dual-Antenna Diversity configurations on prototype transceiver handsets in an indoor environment. The statistics of the received signal are evaluated, and the envelope correlation coefficients for the signals received by the Antennas are computed. Results from simulations performed using accurate representations of the Antenna patterns coupled with an indoor propagation channel are compared to the measured data. Both the simulations and measurements show the highly decorrelated nature of the received signals, implying that the chosen configurations should provide good Diversity performance