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  • 1.
    Alayon Glasunov, Andrés
    et al.
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Prasad, S.
    Händel, Peter
    KTH, School of Electrical Engineering (EES), Signal Processing. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Experimental characterization of the propagation channel along a very large virtual array in a reverberation chamber2014In: Progress in Electromagnetics Research B, ISSN 1937-6472, no 59, 205-217 p.Article in journal (Refereed)
    Abstract [en]

    We show that the combined use of radio frequency absorbers and directive antennas can produce significant changes of the radio propagation channel properties along the positions of a virtual array inside a reverberation chamber. A multidimensional characterization of the channel was performed at 40 antenna positions with spacing of 0:233λ at 1 GHz. The average power, the Ricean K-factor, the coherence bandwidth, the r.m.s. delay spread, the mean delay, the beamforming power angle spectrum and array antenna correlation have been studied for different arrangements in the reverberation chamber. The analysis shows that the joint average over time and frequency channel behavior is, as expected, rather homogeneous along the very large array. However, individual realizations of the channel present a pronounced selective behavior in space, time and frequency with parameters varying along the positions of the virtual array suggesting that a heterogeneous behavior of the radio channels can be emulated in reverberation chambers. An important application of the presented study comprises testing of antenna array designs and algorithms in multipath environments. Further development may lead to Over The Air testing of Multiple Input Multiple Output antenna systems of various sizes, i.e., from small to very large arrays.

  • 2.
    Alayon Glazunov, Andres
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    A Monte Carlo study on the diversity measure of a spherical volume2012In: Proceedings of 6th European Conference on Antennas and Propagation, EuCAP 2012, 2012, 21-24 p.Conference paper (Refereed)
    Abstract [en]

    In this paper we investigate the diversity measure ψ(R h) of MIMO (Multiple-Input Multiple-Output) channels based on the eigenvalues of the full-correlation matrix of the channel matrix R h. We apply this definition to antennas and channels based on the antenna scattering matrix and the spherical vector wave (svw) expansion of the electromagnetic fields. We derive bounds for this diversity measure in an isotropic propagation channel. We further analyze the diversity measure of a spherical volume occupied by decoupled λ/2-dipole antennas by means of Monte Carlo simulations assuming different polarizations, e.g., vertically or horizontally polarizations, 2 orthogonal polarizations and 3 orthogonal polarizations.

  • 3.
    Alayon Glazunov, Andres
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    A survey of the application of the spherical vector wave mode expansion approach to antenna-channel interaction modeling2014In: Radio Science, ISSN 0048-6604, E-ISSN 1944-799X, Vol. 49, no 8, 663-679 p.Article in journal (Refereed)
    Abstract [en]

    This paper provides an overview of recent advances in the modeling, analysis, and measurements of interactions between antennas and the propagation channel in multiple antenna systems based on the spherical vector wave mode expansion of the electromagnetic field and the antenna scattering matrix. It demonstrates the importance and usefulness of this approach to gain further insights into a variety of topics such as physics-based propagation channel modeling, mean effective gain, channel correlation, propagation channel measurements, antenna measurements and testing, the number of degrees of freedom of the radio propagation channel, channel throughput, and diversity systems. The paper puts particular emphasis on the unified approach to antenna-channel analysis at the same time as the antenna and the channel influence are separated. Finally, the paper provides the first bibliography on the application of the spherical vector wave mode expansion of the electromagnetic field to antenna-channel interactions.

  • 4.
    Alayon Glazunov, Andres
    Ericsson research.
    Considerations regarding the number of RAKE fingers required in CDMA RAKE receivers1998Conference paper (Other academic)
  • 5.
    Alayon Glazunov, Andres
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Expansion of the Kronecker and Keyhole Channels Into Spherical Vector Wave Modes2011In: IEEE Antennas and Wireless Propagation Letters, ISSN 1536-1225, E-ISSN 1548-5757, Vol. 10, 1112-1115 p.Article in journal (Refereed)
    Abstract [en]

    In this letter, we provide additional results on the expansion of wireless channels into spherical vector wave multipole modes. We specialize our results to multiple-input-multiple-output (MIMO) channels with Kronecker-product structure of the correlation matrix: 1) the Kronecker channel, and 2) the Keyhole channel. We show that the Kronecker or Keyhole structure of the multimode channel matrix implies the corresponding structure in the MIMO channel matrix. Moreover, we show that the separability of the joint probability distribution functions of the angle of arrival (AoA) and the angle of departure (AoD), i.e., the independence between the AoAs and the AoDs for co- and cross-polarized components results in a Kronecker-product structure of the full-correlation matrix of the multimode matrix for both the Kronecker and the Keyhole channels.

  • 6. Alayon Glazunov, Andres
    ITU-R, WP-3K/36, 3M/117, Average building attenuation for indoor to satellite interferencepropagation at 5 GHz1999Report (Other academic)
  • 7.
    Alayon Glazunov, Andres
    Ericsson Research.
    ITU-R, WP-3K/69, 3M/153, Building attenuation loss measurements at the 5GHz in an officebuilding area2000Report (Other academic)
  • 8.
    Alayon Glazunov, Andres
    TeliaSonera.
    Joint impact of the mean effective gain and base station smart antennas on WCDMA-FDD systems performance2004Conference paper (Refereed)
  • 9.
    Alayon Glazunov, Andres
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Maximum joint transmit-receive MRC gain with antennas exciting spherical vector wave modes up to order l2012In: Electronics Letters, ISSN 0013-5194, E-ISSN 1350-911X, Vol. 48, no 24, 1520-1521 p.Article in journal (Refereed)
    Abstract [en]

    Derived is the maximum joint transmit and receive maximum ratio combining (MRC) diversity gain in arbitrary MIMO (multiple-input multiple-output) wireless propagation channels and the corresponding transmit and receive antenna coefficients. Also provided are numerical examples addressing two generic MIMO channel models based on the Kronecker correlation model with Laplacian angle-of-arrival (AoA) and angle-of-departure (AoD) distributions. In the analysis, spherical vector wave multipole modes of order l are considered, including both TE and TM modes.

  • 10.
    Alayon Glazunov, Andres
    Telia Research.
    Mean effective gain of user equipment antennas in double directional channels2004In: Proc. 15th IEEE Int. Symp. Personal, Indoor and Mobile Radio Communications PIMRC 2004, 2004, Vol. 1, 432-436 p.Conference paper (Refereed)
    Abstract [en]

     This paper presents a revised definition of the Mean Effective Gain (MEG) of terminal antennas. It now includes the gain pattern of both the transmitting (BS) and receiving (MS) antennas, the path gain matrix as well as the joint angular power distributions of the two orthogonal polarizations at both ends. A closed form equation is provided followed by the analysis of some special cases and their practical implications.

  • 11.
    Alayon Glazunov, Andres
    Telia Sonera.
    Measurements of Radio Performances of UMTS Terminals in Speech Mode, (R4-040612), 3GPPTSG-RAN Working Group 4 (Radio) meeting #33, Yokohama, 15 - 19 Nov 20042004Report (Other academic)
  • 12.
    Alayon Glazunov, Andres
    Lund University.
    On the Antenna-Channel Interactions: A Spherical Vector Wave Expansion Approach2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The main focus of this thesis is the analysis of the interactions between antennas and channels where electromagnetic fields play a central role. Our goal has been to devise a general framework to enable a clear separation of the properties of the propagation channel from the influence of the antennas at the same time as it provides a common ground for a joint characterization of their properties. For this we have taken help of two tools: 1) a solution to Maxwell’s equations, i.e., a spherical vector wave (svw) multi-modal expansion of the electromagnetic field and 2) the scattering matrix representation of an antenna that provides a full description of all its properties as a transmitting, receiving or scattering device. These tools offer a natural characterization of the polarizational, directional, and spatial properties of multiple-input multiple-output (MIMO) antenna systems. In this thesis we first show that under some assumptions the propagation channel and the antenna are equivalent. The equivalence is in the sense that the impact of the channel cross-polarization ratio (XPR) and the antenna effective cross-polarization discrimination (XPD) on the mean effective gain (MEG) of an antenna are symmetrical. We also find bounds on the MEG in a wireless channel. Then we provide closed form expressions for the covariance of the field multi-modes as a function of the Power Angle Spectrum (PAS) and the channel XPR. A new interpretation of the MEG of antennas in terms of field multi-modes is also provided where the maximum MEG is obtained by conjugate mode matching between the antennas and the channel. We also show the (intuitive) result that the optimum decorrelation of the antenna signals is obtained by the excitation of orthogonal spherical vector wave modes. The cross-correlation coefficient between signals at two antenna branches (ports) in the presence of spatially selective interference and additive white gaussian noise is also investigated showing that spatial interference can also be readily modeled in terms of the svw mode expansion. We further devise a correlation model for co- and cross-polarized field components and introduce the concept of mode-to-mode channel mapping, the M-matrix, between the receive and transmit antenna modes. The M-matrix maps the modes excited by the transmitting antenna to the modes exciting the receive antennas and vice versa. The covariance statistics of this M-matrix are expressed as a function of the double-directional power-angular spectrum (PAS) of co- and cross-polarized components of the electromagnetic field. We finally derive physical limitations on the interactions of antennas exciting TM or TE modes (but not both) and wireless propagation channels. Rather than maximizing antenna gain in a single direction we obtain physical limitations on the antenna gain pattern, which is directly translated to more condensed parameters, i.e. the instantaneous effective gain Gi and the mean effective gain Ge if instantaneous realizations or correlation statistics of the expansion coefficients of the electromagnetic field are known, respectively. The obtained limitations are on the maximum of Gi/Q and Ge/Q, which establish a trade-off between link gain and the antenna quality factor Q.

  • 13.
    Alayon Glazunov, Andres
    Ericsson research.
    On the distribution of relevant radio channel figures in different propagationenvironments for performance evaluation of WCDMA systems2001Conference paper (Refereed)
  • 14.
    Alayon Glazunov, Andres
    Telia Research.
    On the User Equipment Antenna Performance2004In: In Proceedings of Joint COST273 & COST284 Workshop, 2004Conference paper (Refereed)
  • 15.
    Alayon Glazunov, Andres
    Telia Research.
    Performance analysis of impulse radio based on ultra wideband channelmodel for indoor communications2002Conference paper (Refereed)
  • 16.
    Alayon Glazunov, Andres
    Telia Research.
    Theoretical analysis of mean effective gain of mobile terminal antennasin Ricean channels2002Conference paper (Refereed)
  • 17.
    Alayon Glazunov, Andres
    Telia Sonera.
    UE antenna efficiency- a comparison of different figures of merit, (R4-030994), TSG-RANWorkingGroup 4 (Radio) meeting #29, San Diego, US, 17th-21st Nov 20032003Report (Other academic)
  • 18.
    Alayon Glazunov, Andres
    TeliaSonera.
    UE antenna efficiency impact on UMTS system/coverage capacity, (R4-030546), 3GPP, TSGRANWorking Group 4 (Radio) meeting #27, Paris, France 19th-23rd May 20032003Report (Other academic)
  • 19.
    Alayon Glazunov, Andres
    et al.
    Ericsson Research.
    Asplund, Henrik
    Ericsson Research.
    Berg, Jan-Erik
    Ericsson Research.
    Statistical analysis of measured shorttermimpulse response functions of 1.88 GHz radio channels in Stockholm with correspondingchannel model1999Conference paper (Refereed)
  • 20.
    Alayon Glazunov, Andres
    et al.
    Ericsson Research.
    Berg, Jan-Erik
    Ericsson Research.
    Building shielding loss modeling2000Conference paper (Refereed)
  • 21.
    Alayon Glazunov, Andres
    et al.
    KTH, School of Electrical Engineering (EES). Lund University, Sweden.
    Gustafsson, Mats
    Molisch, Andreas F.
    On the Physical Limitations of the Interaction of a Spherical Aperture and a Random Field2011In: IEEE Transactions on Antennas and Propagation, ISSN 0018-926X, E-ISSN 1558-2221, Vol. 59, no 1, 119-128 p., 5618544Article in journal (Refereed)
    Abstract [en]

    This paper derives physical limitations on the interactions of antennas exciting TM or TE modes (but not both) and wireless propagation channels. The derivation is based on the spherical vector wave expansion of the electromagnetic field outside a sphere circumscribing the antennas. The result is an extension of the seminal work of Chu on the classical limitations on maximum antenna gain and radiation Q. Rather than maximizing antenna gain in a single direction we obtain physical limitations on the antenna gain pattern, which is directly translated to more condensed parameters, i.e., the instantaneous effective gain G(i) and the mean effective gain G(e) if instantaneous realizations or correlation statistics of the expansion coefficients of the electromagnetic field are known, spectively. The obtained limitations are on the maximum of G(i)/Q and G(e)/Q, which establish a trade-off between link gain and Q.

  • 22.
    Alayon Glazunov, Andres
    et al.
    Lund University.
    Gustafsson, Mats
    Lund University.
    Molisch, Andreas F.
    Lund University.
    Tufvesson, Fredrik
    Lund University.
    Physical modelling of multiple-input multiple-output antennas and channels by means of the spherical vector wave expansion2010In: IET Microwaves, Antennas & Propagation, ISSN 1751-8725, Vol. 4, no 6, 778-791 p.Article in journal (Refereed)
    Abstract [en]

     The authors propose a new physically motivated model that allows the study of the interaction between the antennas and the propagation channel for multiple-input multiple-output (MIMO) systems. The key tools employed in the model are the expansion coefficients of the electromagnetic field in spherical vector waves and the scattering matrix representation of the properties of the antenna. The authors derive the expansion of the MIMO channel matrix, H, in spherical vector wave modes of the electromagnetic field of the antennas as well as the propagation channel. The authors also introduce the channel scattering dyadic, C, with a corresponding correlation model for co-polarised and cross-polarised elements and introduce the concept of mode-to-mode channel mapping, the M-matrix, between the receive and transmit antenna modes. The M-matrix maps the modes excited by the transmitting antenna to the modes exciting the receive antennas and vice versa. The covariance statistics of this M-matrix are expressed as a function of the double-directional power-angular spectrum (PAS) of co-polarised and cross-polarised components of the electromagnetic field. Their approach aims at gaining insights into the physics governing the interaction between antennas and channels and it is useful for studying the performance of different antenna designs in a specified propagation channel as well as for modelling the propagation channel. It can furthermore be used to quantify the optimal properties of antennas in a given propagation channel. The authors illustrate the developed methodology by analysing the interaction of a 2 x 2 system of slant polarised half-wavelength dipole antennas with some basic propagation channel models.

  • 23.
    Alayon Glazunov, Andres
    et al.
    Lund University.
    Gustafsson, Mats
    Lund University.
    Molisch, Andreas F.
    Lund University.
    Tufvesson, Fredrik
    Lund University.
    Kristensson, Gerhard
    Lund University.
    Spherical Vector Wave Expansion of Gaussian Electromagnetic Fields for Antenna-Channel Interaction Analysis2009In: IEEE Transactions on Antennas and Propagation, ISSN 0018-926X, E-ISSN 0096-1973, Vol. 57, no 7, 2055-2067 p.Article in journal (Refereed)
    Abstract [en]

    In this paper, we introduce an approach to analyze the interaction between antennas and the propagation channel. We study both the antennas and the propagation channel by means of the spherical vector wave mode expansion of the electromagnetic field. Then we use the expansion coefficients to study some properties of general antennas in thosefields by means of the antenna scattering matrix. The focus is on the spatio-polar characterization of antennas, channels and their interactions. We provide closed form expressions for the covariance of the field multimodes as function of the power angle spectrum (PAS) and the channel cross-polarization ratio (XPR). A new interpretation of the mean effective gains (MEG) of antennas is also provided. The maximum MEG is obtained by conjugate mode matching between the antennas and the channel; we also prove the (intuitive) results that the optimum decorrelation of the antenna signals is obtained by the excitation of orthogonal spherical vector modes.

  • 24.
    Alayon Glazunov, Andres
    et al.
    Ericsson Research.
    Hamberg, Lennart
    Ericsson research.
    Medbo, Jonas
    Building shielding loss measurementsand modeling at the 5GHz band in office building areas2000Conference paper (Refereed)
  • 25.
    Alayon Glazunov, Andres
    et al.
    Telia Research.
    Karlsson, Peter
    Telia Research.
    Ljung, Rickard
    Telia research.
    Cost analysis of smart antenna systems deployment2005In: Proc. VTC 2005-Spring Vehicular Technology Conf. 2005 IEEE 61st, 2005, Vol. 1, 329-333 p.Conference paper (Refereed)
    Abstract [en]

    3G networks and services are being launched all over the world The basic investments on equipment have already been done according to preliminary traffic forecasts. However, if the mobile data traffic acquires "internet- like" proportions, network capacity shortage will become a reality in densely populated areas, such as city centers and business parks. In that case smart antennas may be the solution. Based on this assumption the financial aspects of the deployment of smart antenna systems in the 3G UMTS networks have been evaluated. We have evaluated the potential CAPEX and OPEX savings provided by such a system compared to more conventional antenna systems. Despite their indicative nature, our calculations show that cost savings of the order of 10% to 25% are feasible if the cost increase of the smart antenna equipment is of the order of 100% to 50% of the conventional antennas equipment costs, respectively.

  • 26.
    Alayon Glazunov, Andres
    et al.
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Kolmonen, Veli-Matti
    Aalto University, Finland.
    Laitinen, Tommi
    Aalto University, Finland.
    MIMO Over-the-Air Testing2012In: LTE-Advanced and Next Generation Wireless Networks: Channel Modelling and Propagation, Chichester, U.K.: John Wiley & Sons, 2012, 411-441 p.Chapter in book (Refereed)
  • 27.
    Alayon Glazunov, Andres
    et al.
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Lai, Zhihua
    Ranplan Wireless Network Design Ltd., United Kingdom.
    Zhang, Jie
    University of Sheffield, United Kingdom.
    Outdoor-Indoor Channel2012In: LTE-Advanced and Next Generation Wireless Networks: Channel Modelling and Propagation, Chichester, U.K.: John Wiley & Sons, 2012, 123-151 p.Chapter in book (Refereed)
  • 28.
    Alayon Glazunov, Andres
    et al.
    Lund University.
    Molisch, Andreas F.
    Lund University.
    Tufvesson, Fredrik
    Lund University.
    Fading characterization in a semi-anechoic chamber with artificial scatterers for Mean Effective Gain measurements of wireless handheld terminals2008In: 2008 IEEE Radio and Wireless Symposium, RWS, 2008, 611-614 p.Conference paper (Refereed)
    Abstract [en]

    This paper presents the methodology and corresponding analysis of the scattered field measurements in a semi-anechoic ferrite-lined chamber. The focus is on recreating a Rayleigh fading environment with realistic cross-polarization ratio (XPR) with the purpose of measuring the Mean Effective Gain (MEG) of mobile handheld terminal operating in the 900 MHz GSM band. The emulated XPR was similar in each of the studied scenarios and approximately equal to 12 dB. The Rayleigh fading hypothesis for the statistics of the envelope of the measured signals could not be rejected in most cases at the 95 % level with the Kolmogorov goodness-of-fit test.

  • 29.
    Alayon Glazunov, Andres
    et al.
    Lund University.
    Molisch, Andreas F.
    Lund University.
    Tufvesson, Fredrik Tufvesson
    Lund University.
    Mean effective gain of antennas in a wireless channel2009In: IET Microwaves, Antennas & Propagation, ISSN 1751-8725, Vol. 3, no 2, 214-227 p.Article in journal (Refereed)
    Abstract [en]

    The mean effective gain (MEG) is one of the most important parameters for the characterisation of antennas in wireless channels. An analysis of some fundamental properties of the MEG is provided and corresponding physical interpretations are given. Three points are analysed in detail: (i) closed-form expressions for MEG in a mixed environment with both stochastic and deterministic components are provided, showing that the MEG can be written as a sum of gains for the deterministic and stochastic components, (ii) it is shown that under some assumptions, the propagation channel and the antenna are equivalent in the sense that the impact of the channel cross-polarisation ratio (XPR) and the antenna effective cross-polar discrimination on the MEG are symmetrical, (iii) based on the fact that MEG depends on random variables, such as the XPR and antenna rotations because of user's movements, the average, the minimum and maximum MEG of antennas are defined, respectively. Finally, the maximum effective gain of antennas is derived and shown that it is bounded by 4 pi eta(rad), where eta(rad) is the radiation efficiency of the antenna.

  • 30.
    Alayon Glazunov, Andres
    et al.
    Telia Research.
    Pasalic, Ermin
    Comparison of MEG and TRPG of practical antennas2004In: Proc. 15th IEEE Int. Symp. Personal, Indoor and Mobile Radio Communications PIMRC 2004, 2004, Vol. 1, 627-631 p.Conference paper (Refereed)
    Abstract [en]

    In this paper two figures of merit of UE antenna performance are compared, the Mean Effective Gain (MEG) and the Total Radiated Power Gain (TRPG). The ratio between these magnitudes has been evaluated first theoretically and later from measurements of four different handsets in the GSM, AMPS bands. In the evaluation different power angular distribution models were assumed. It is also shown that in practice an estimate of MEGcould be obtained from the TRPG.

  • 31.
    Alayon Glazunov, Andres
    et al.
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Prasad, Sathyaveer
    KTH, School of Electrical Engineering (EES), Signal Processing.
    Händel, Peter
    KTH, School of Electrical Engineering (EES), Signal Processing. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Bolin, Thomas
    Prytz, Kjell
    Impact of Scattering Within a Multipath Simulator Antenna Array on the Ricean Fading Distribution Parameters in OTA Testing2014In: IEEE Transactions on Antennas and Propagation, ISSN 0018-926X, E-ISSN 0096-1973, Vol. 62, no 6, 3257-3269 p.Article in journal (Refereed)
    Abstract [en]

    In this paper, we investigate the unwanted scattering that exists within the multipath simulator (MPS) array antennas employed in over the air (OTA) testing of mobile terminals. The impact of scattering is evaluated in terms of the measurement uncertainty of the average received power and the Ricean K-factor. The maximum ratio combining diversity is investigated for a generic device under test comprising two half-wavelength dipole antennas. We provide closed-form expressions for the uncertainties of the average received power and the Ricean K-factor for a uniform circular array of MPS antennas and a 2-D uniformly distributed angle-of-arrival spectrum. We also derive the maximum number of MPS antennas and the minimum ring radius of the MPS system as a function of the separation between the most distant antenna elements if the device under test employs a uniform linear array. As a result, we provide design guidelines for MPS array in terms of the number antennas, the radius of the MPS array and the wavelength of the carrier frequency.

  • 32.
    Alayon Glazunov, Andres
    et al.
    Lund University.
    Tufvesson, Fredrik
    Lund University.
    Gustafsson, Mats
    Lund University.
    Molisch, Andreas F.
    Lund University.
    Kristensson, Gerhard
    Lund University.
    Branch cross-correlation in presence of spatially selective interference expressed in terms of the spherical vector wave expansion of the electromagnetic field2008Conference paper (Refereed)
    Abstract [en]

    In this paper we present an analysis of the cross-correlation coe±cient between signals at two antennabranches (ports) in the presence of spatially selective interference and additive white gaussian noise. Morespeci¯cally, we look at a §45± slanted polarization diversity arrangement, which is rotated around the axisperpendicular to the plane containing the antennas. Results are provided as a function of the rotation angle.The analysis is based on the spherical vector wave multi-pole expansion of both the ¯eld impinging on theantennas and the antenna radiation properties.

  • 33.
    Alayon Glazunov, Andres
    et al.
    Lund University.
    Tufvesson, Fredrik
    Lund University.
    Gustafsson, Mats
    Lund University.
    Molisch, Andreas F.
    Lund University.
    Kristensson, Gerhard
    Lund University.
    On the mean effective gain expressed in terms of the spherical vector wave expansion of the electromagnetic field2008Conference paper (Refereed)
    Abstract [en]

    The mode expansion o®ers a general framework for the analysis of the interaction between antennas andpropagation channels. In this paper, the Mean E®ective Gain (MEG) of an antenna is expressed in termsof the spherical vector wave expansion of the electromagnetic ¯eld. An explicit expression of the MEG isprovided as a function of the normalized average power of modes excited in the propagation channel andthe correlation between the channel modes due to the polarization and spatial selectivity of plane wavesimpinging at the antenna.

  • 34.
    Alayon Glazunov, Andres
    et al.
    Lund University.
    Tufvesson, Fredrik
    Lund University.
    Molisch, Andreas F.
    Lund University.
    A note on the Mean Effective Radiated Power and the Mean Effective Receiver Sensitivity of mobile handheld terminals2008In: 2008 IEEE International Symposium on Antennas and Propagation and USNC/URSI National Radio Science Meeting, 2008, 1-4 p.Conference paper (Refereed)
    Abstract [en]

     In this paper we introduce the Mean Effective Radiated Power (MERP) and the Mean Effective Radiated Sensitivity (MERS) as alternative figures of merit of the uplink and downlink communication performance of wireless handheld terminals. We show how they are related to the Mean Effective Gain (MEG), the total radiated power (TRP) and total receiver sensitivity (TRS).

  • 35.
    Alayon Glazunov, Andres
    et al.
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Zhang, Jie
    University of Bedfordshire.
    Clustering impact on the statistics of the multipole expansion coefficients of a wireless channel2011In: Progress in Electromagnetics Research Symposium, 2011, 603-607 p.Conference paper (Refereed)
    Abstract [en]

    It has been widely known that experimental results show that multipath components seem to arrive at the receiver in concentrated groups. These groups of multipath components, or clusters, are usually a result of scattering from large physical structures. Their impact on the capacity of Multiple-Input Multiple-Output (MIMO) systems has been widely studied. However, their impact on the spherical vector waves (svw) expansion of the propagation channel has not yet been addressed in the literature. As we have recently shown, a svw expansion provides a compact and straightforward representation of both antennas and channels. This can potentially facilitate designing antennas tailored to take advantage of the spatial and polarimetric characteristics of the propagation environment, which is essential to the deployment of efficient wireless networks. In this paper, we therefore study the impact of clustering on the first and second order statistics of the multimode expansion coefficients. We adopt the simulation approach to exemplify our results and provide numerical examples.

  • 36.
    Alayon Glazunov, Andres
    et al.
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Zhang, Jie
    The University of Sheffield.
    On Some Optimal MIMO Antenna Coefficients in Multipath Channels2011In: Progress in Electromagnetics Research B, ISSN 1937-6472, Vol. 35, 87-109 p.Article in journal (Refereed)
    Abstract [en]

    This paper derives some optimum transmit and receive antenna coefficients in wireless multipath channels based on the spherical vector wave multimode expansion of the multiple-input multiple-output (MIMO) channel matrix. The derived antenna coefficients satisfy the following specific optimization criteria: (i) maximum MIMO mean effective link gain (link MEG) based on the multimode channel realizations or (ii) maximum MIMO link MEG based on the multimode correlation matrix or (iii) correlation minimization by diagonalization of the MIMO full-correlation matrix. It is shown that the proposed approach leads to matrix equations belonging to the nearest Kronecker product (NKP) problem family, which in general have no trivial solution. However, we show that exact solutions are provided to the posed NKP problems under the assumption of the Kronecker model for the MIMO full-correlation matrix. The results are illustrated by numerical examples. The proposed approach is a complement to existing antenna pattern analysis methods.

  • 37.
    Alayon Glazunov, Andres
    et al.
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Zhang, Jie
    Lund University.
    Some Examples of Uncorrelated Antenna Radiation Patterns for MIMO Applications2011In: Progress in Electromagnetics Research Symposium, 2011, 598-602 p.Conference paper (Refereed)
    Abstract [en]

    In this paper, we provide some examples of an approach resulting in uncorrelatedantenna radiation patterns at both ends of a MIMO (Multiple-Input Multiple-Output) wireless link in a given propagation channel. The patterns of antennas exciting dipole or dipole and quadrupole TE and TM modes are analyzed for two generic MIMO channel models based on the Kronecker correlation model with Laplacian angle-of-arrival (AoA) and angle-of-departure (AoD) distributions. The presented results are of a fundamental nature and essential to achieve the promise of MIMO systems.

  • 38.
    Asplund, Henrik
    et al.
    Ericsson Research.
    Alayon Glazunov, Andres
    Ericsson Research.
    Berg, Jan-Erik
    Ericsson Research.
    An investigation of measured and simulated wideband channels with applications to 1.25 MHz and 5 MHz CDMA systems1998Conference paper (Refereed)
  • 39.
    Asplund, Henrik
    et al.
    Ericsson Research.
    Alayon Glazunov, Andres
    Ericsson Research.
    Molisch, Andreas F.
    Nachrichtentechnik und Höchfrequenztechnik (INTHF) of the TU Wien.
    Pedersen, Klaus I.
    Aalborg University.
    Steinbauer, Martin
    Nachrichtentechnik und Höchfrequenztechnik (INTHF) of the TU Wien.
    The COST 259 Directional Channel Model-Part II: Macrocells2006In: IEEE Transactions on Wireless Communications, ISSN 1536-1276, E-ISSN 1558-2248, Vol. 5, no 12, 3434-3450 p.Article in journal (Refereed)
    Abstract [en]

    This paper describes the attributes of the COST 259 directional channel model that are applicable for use in the design and implementation of macrocellular mobile and portable radio systems and associated technology. Special care has been taken to model all propagation mechanisms that are currently understood to contribute to the characteristics of practical macrocellular channels and confirm that large scale, small scale, anddirectional characteristics of implemented models are realistic through their comparison with available measured data. The model that is described makes full use of previously published work, as well as incorporating some new results. It is considered that its implementation should contribute to a tool that can be used for simulations and comparison of different aspects of a large variety of wireless communication systems, including those that exploit the spatial aspects of radio channels, as, for example, throughthe use of adaptive antenna systems. 

  • 40.
    Dahlen, Anders
    et al.
    TeliaSonera.
    Alayon Glazunov, Andres
    TeliaSonera.
    Admission control at UMTS spectrum sharing2005Conference paper (Refereed)
  • 41.
    de la Roche, Guillaume
    et al.
    Mindspeed Technologies, France.
    Alayon Glazunov, AndresKTH, School of Electrical Engineering (EES), Electromagnetic Engineering.Allen, BenUniversity of Bedfordshire, United Kingdom.
    LTE-Advanced and Next Generation Wireless Networks: Channel Modelling and Propagation2012Collection (editor) (Refereed)
    Abstract [en]

    LTE- A and Next Generation Wireless Networks: Channel Modeling and Performance describes recent advances in propagation and channel modeling necessary for simulating next generation wireless systems. Due to the radio spectrum scarcity, two fundamental changes are anticipated compared to the current status. Firstly, the strict reservation of a specific band for a unique standard could evolve toward a priority policy allowing the co-existence of secondary users in a band allocated to a primary system. Secondly, a huge increase of the number of cells is expected by combining outdoor base stations with smaller cells such as pico/femto cells and relays. This evolution is accompanied with the emergence of cognitive radio that becomes a reality in terminals together with the development of self-organization capabilities and distributed cooperative behaviors. The book is divided into three parts: Part I addresses the fundamentals (e.g. technologies, channel modeling principles etc.). Part II addresses propagation and modeling discussing topics such as indoor propagation, outdoor propagation, etc. Part III explores system performance and applications (e.g. MIMO Over-the-air testing, electromagnetic safety, etc).

  • 42. Degauque, Pierre
    et al.
    Alayon Glazunov, Andres
    TeliaSonera.
    Sibille, Alain Sybille
    Pamp, Jörg
    Antennas and diversity: from narrowband to ultra-wide band.2006In: Mobile Broadband Multimedia Networks: Techniques, Models and Tools for 4G / [ed] Correia, L., Academic Press, 2006, 218-276 p.Chapter in book (Other academic)
    Abstract [en]

    This chapter provides new insights on antennas, including diversity schemes and UWB applications. It is important to remember that antenna performances are strongly dependent on the electromagnetic properties of the medium in its immediate vicinity. This is a critical point for handset antennas, for example, since the user's hand and body strongly affect the radiation efficiency. Taken together, the total radiated power in the transmission mode and the total radiated sensitivity in the receiving mode provide a general idea of the handset terminal's behaviour in its environment. However, as outlined in Section 5.2, in order to characterise antenna efficiency precisely, it is first necessary to introduce and define such figures of merit as the mean effective gain and the mean effective radiated power, taking the multipath structure of the communication channel into account. For this, measurement techniques must be reproducible. Two of these techniques have been studied in depth. In the first, which is based on the use of a reverberation chamber, multiple reflections on the walls reproduce ideal Rayleigh channels; in the second, the transmitting antenna is placed in an anechoic chamber, allowing the modification of the antenna radiation pattern, due to a phantom that simulates the user's body, to be clearly demonstrated. One of the main factors influencing the measurement results is, of course, the electrical properties of the phantom material. However, both the position of the phantom hand, or in other words, the way a handset is held, and the position of the antenna handset relative to the head are also quite critical. These issues of measurement repeatability and accuracy were widely discussed during the COST 273 Action, with a focus on updating the standardised measurement techniques.

  • 43. Fang, C.
    et al.
    Allen, B.
    Liu, E.
    Karadimas, P.
    Zhang, J.
    Alayon Glazunov, Andres
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Tufvesson, F.
    Indoor-indoor and indoor-outdoor propagation trial results at 2.6 GHz2012In: Antennas and Propagation Conference (LAPC), 2012 Loughborough, IEEE , 2012, 6403064- p.Conference paper (Refereed)
    Abstract [en]

    This paper presents delay spread, coherence bandwidth, and angle-of-arrival statistics derived from an extensive MIMO channel measurement campaign carried out at a central frequency of 2.6GHz. The measurement scenarios include indoor-indoor, indoor-outdoor and indoor-outdoor-indoor. The results are useful for analytical and performance studies of post-3G wireless communication systems such as femtocell design and deployment.

  • 44.
    Gao, Xiang
    et al.
    University of Bedfordshire.
    Alayon Glazunov, Andres
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Weng, Jialai
    University of Bedfordshire.
    Fang, Cheng
    University of Bedfordshire.
    Zhang, Jie
    University of Bedfordshire.
    Tufvesson, Fredrik
    Lund University.
    Channel measurement and characterization of interference between residential femto-cell systems2011In: Proceedings of the 5th European Conference on Antennas and Propagation, EUCAP 2011, 2011, 3769-3773 p.Conference paper (Refereed)
    Abstract [en]

    Interference between femto-cell systems is a critical factor for the deployment of such systems in, e.g., residential areas. In this paper we report on a residential channel measurement campaign focusing on the channel properties for femto-cell systems. We characterize basic channel properties such as delay spread and interference levels between different furnished residential houses. In addition we also study the spatial separation between channels from different houses to investigate whether directional properties can be used to mitigate interference in such scenarios.

  • 45.
    Glazunov, Andrés Alayón
    et al.
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Bäckström, Mats
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering. Saab Aeronautics, Sweden.
    Oakes, Benjamin Donald
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Probability Distribution Function of the Electric Field Strength From a CW IEMI Source2014In: IEEE transactions on electromagnetic compatibility (Print), ISSN 0018-9375, Vol. 56, no 6, 1550-1558 p.Article in journal (Refereed)
    Abstract [en]

    A statistical method for predicting the vulnerability of a target, i.e., critical equipment, located inside a building subject to a radiated Intentional Electromagnetic Interference (IEMI) source outside a building, has been devised. Combining probability density functions of small-and large-scale fluctuations of the electric field strength results in a Suzuki distributed electric field strength impinging at the equipment. Specifying the susceptibility level or the critical electric field strength of the target, the vulnerability of a target is evaluated as a function of the distance between source and target, taking into account losses from in and outside the building. Vulnerability isocontours defined as lines of constant probability of exceeding the susceptibility level are presented for a generic, continuous wave power source in a scenario emulating a dense urban microcell propagation environment. A comparison of the vulnerabilities predicted based on the Suzuki and the Log-normal distributions are also been provided for the same scenario. The proposed method provides estimates of critical distances of radiated IEMI attacks and may have use when deciding on the perimeter defense of a facility.

  • 46.
    Medbo, Jonas
    et al.
    Ericsson Research.
    Berg, Jan-Erik
    Ericsson Research.
    Alayon Glazunov, Andres
    Ericsson Research.
    Combined direction-delay channel characteristicsat 5 GHz in typical office environment2001Conference paper (Refereed)
  • 47.
    Oakes, Benjamin Donald
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Mattsson, Lars-Göran
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Näsman, Per
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Glazunov, Andrés Alayón
    A Systems-Based Risk Assessment Framework for Intentional Electromagnetic Interference (IEMI) on CriticalInfrastructuresArticle in journal (Refereed)
  • 48.
    Zhang, Shuai
    et al.
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Alayón Glazunov, Andrés
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Ying, Zhinong
    He, Sailing
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Reduction of the envelope correlation coefficient with improved total efficiency for mobile LTE MIMO antenna arrays: Mutual scattering mode2013In: IEEE Transactions on Antennas and Propagation, ISSN 0018-926X, E-ISSN 0096-1973, Vol. 61, no 6, 3280-3291 p.Article in journal (Refereed)
    Abstract [en]

    A mutual scattering mode is introduced in this paper. Utilizing this mode, the correlation of a lossy long-term evolution (LTE) multiple-input and multiple-output (MIMO) antenna array can be reduced efficiently, even down to zero, by increasing the Q factors of the MIMO antenna elements. In practice, the Q factors can be straight forwardly tuned through different input impedance matching. The zero correlation occurs at a Q factor higher than that resulting from the conjugate input impedance matching. On one hand, if the inter-element distance is larger than a certain distance (what we denominate as the Critical Distance), the total efficiency can also be improved in addition to reducing the correlation. On the other hand, when the inter-element distance is less than the critical distance, a reference MIMO antenna with high correlation and high total efficiency is obtained. This antenna can well be proposed for over-the-air (OTA) measurement applications. The introduced scattering mode is investigated for dual monopoles on a large lossy ground plane and for various mobile terminal MIMO antenna designs. A wideband MIMO antenna, with multiple resonances, covering the band 746-870 MHz is proposed with the envelope correlation coefficient and total efficiency less than 0.5 and higher than 50% (-3 dB), respectively. Measurements and simulations agree well for all the fabricated prototypes. The envelope correlations and the multiplexing efficiencies of the prototypes are also investigated in propagation channels with Gaussian distributed angle of arrivals.

  • 49.
    Zhang, Xu
    et al.
    University of Bedfordshire.
    Zhou, DiBin
    University of Bedfordshire.
    Xiao, Zhu
    University of Bedfordshire.
    Liu, Enjie
    University of Bedfordshire.
    Zhang, Jie
    University of Bedfordshire.
    Alayon Glazunov, Andres
    University of Bedfordshire.
    Dynamic Group PCI Assignment Scheme2011In: The Seventh International Conference on Wireless and Mobile Communications (ICWMC 2011), 2011, 101-106 p.Conference paper (Refereed)
    Abstract [en]

    The Physical Cell Identity (PCI) is used to identify femtocell in LTE femtocell as the physical layer identity. Due to the fact that a) the PCIs are normally allocated without planning; and b) the limitation of the number of PCI, the cross-tier PCI confusion problem has arisen. The current solution in 3GPP Release 9 is to use Cell Global Identity (CGI) associated with PCI to solve this problem of confusion. However, using CGI has many serious drawbacks. Especially CGI might cause the inbound-handover is failure. In order to mitigate the CGI problem, this research proposes a dynamic PCI assignment scheme of DG-PCI in the macrocell and femtocell environment. The proposed scheme is tested by using system-level simulation. The simulations showed that the approach offers an optimal PCI distribution between macrocell and femtocell. The test showed that the CGI problem can be solved, and hence increase the successful rate of inbound-handover.

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