By Topic

Antennas, 2007. INICA '07. 2nd International ITG Conference on

Date 28-30 March 2007

Filter Results

Displaying Results 1 - 25 of 63
  • [Front cover]

    Page(s): C1
    Save to Project icon | PDF file iconPDF (62 KB)  
    Freely Available from IEEE
  • [Title page]

    Page(s): C2
    Save to Project icon | PDF file iconPDF (62 KB)  
    Freely Available from IEEE
  • Copyright page

    Page(s): ii
    Save to Project icon | PDF file iconPDF (57 KB)  
    Freely Available from IEEE
  • Technical program

    Page(s): iii - viii
    Save to Project icon | PDF file iconPDF (223 KB)  
    Freely Available from IEEE
  • The European Network of Excellence ACE: A model for integration of antenna research activities in Europe

    Page(s): 1 - 3
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (166 KB) |  | HTML iconHTML  

    In this communication, the European (FP6) Network of Excellence ACE (Antenna Center of Excellence) is presented. The main achievements are discussed both at the level of Joint Research & Delta Research Activities, centered on specific research topics (vertical activities ) and at the level of horizontal activities, which are intended to structure and to integrate European research and to provide efficient training, education, dissemination and transfer of results. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Promises of MIMO Systems from a Signal Processing Perspective

    Page(s): 4
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (57 KB) |  | HTML iconHTML  

    Summary form only given. Since the seminal papers from G. J. Foschini et al and E. Telatar more than ten years have been passed by where the potentials of multiple antennas at both ends of a wireless communication link have attracted many researches and engineers. Firstly, started with a huge academic interest MIMO systems have now become also a major topic in the standardization bodies of the next future communication systems and are considered to be a key technology. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Synthesized Antenna Arrays for Future Mobile Networks

    Page(s): 5 - 9
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (648 KB) |  | HTML iconHTML  

    A pattern shaping synthesis method along with a new sidelobe shaping scheme are used to design antenna arrays capable of delivering a much better radiation performance in terms of homogenous coverage and reduced interference with respect to commercial antennas. For verification, radiation within an urban scenario for the region inside and outside the cell has been studied with the aid of a 3D ray-tracing simulator. Results show a 15% radiation reduction outside the cell for the synthesized antenna with respect to commercial antennas under equal coverage conditions. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Temporal Structure of the 60 GHz Wireless Channel

    Page(s): 10 - 14
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (681 KB) |  | HTML iconHTML  

    In this paper, we present the results of a measurement campaign regarding the short range 60 GHz wireless channel. The measurements were performed inside an airplane cabin by the use of a component-based setup covering 1 GHz of bandwidth. We provide the values of fundamental measures like the delay spread of the channel and take a closer look at the structure of the impulse response from a physically-motivated point of view. Using the example of the measured in-cabin channel, we demonstrate an extended versatile evaluation technique to determine the main multipath components (MMPCs) of the channel. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Fast Edge-Diffraction-Based Radio Wave Propagation Model for Graphics Hardware

    Page(s): 15 - 19
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (793 KB) |  | HTML iconHTML  

    Fast radio wave propagation predictions are of tremendous interest, e.g., for planning and optimisation of cellular radio networks. We propose the use of ordinary graphics cards and specialized algorithms to achieve extremely fast predictions. We present a ray-optical approach for wave diffraction at building edges into street canyons, exploiting the programming model of graphics cards. More than twenty predictions per second are achieved in a 7 km2 urban area with a mean squared error of less than 7 dB when compared with measurements. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Different Array Configurations and Realistic Antenna Characteristics in the Downlink of WCDMA-Based Cellular Systems

    Page(s): 20 - 24
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (290 KB) |  | HTML iconHTML  

    The capacity of a WCDMA-based cellular system like a UMTS-FDD network can be highly improved by utilizing the smart antenna concept. The amount of interference power in the entire network can be reduced by employing antenna arrays at the base station side and performing beamforming. The number of antenna elements as well as the characteristics of the single antenna element have a strong influence on the amount of achievable capacity improvement Therefore, close-to-reality investigations on the network capacity must incorporate realistic antenna element characteristics. In this contribution, a UMTS-FDD network equipped with smart antennas at the base stations is analysed on system level to gain insight on the effect of different realistic antenna and array characteristics on the network capacity. For investigations on system level, the limitation of available resources of the cellular network has to be included into the analysis. For this purpose, different types of antenna elements like dipoles and commercially available real-world base station antennas for UMTS are compared for different array topologies in scenarios with and without code limitation. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Satellite Antenna Measurements

    Page(s): 25 - 32
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1167 KB) |  | HTML iconHTML  

    Compact Ranges represent a standard in fast and real-time antenna, RCS and payload measurements. For (communication) satellite antenna testing, besides near-field test facilities, the compensated compact range (CCR) of EADS Astrium was identified as preferred and highly accurate test facility by worldwide leading satellite manufacturers. Within this paper, the CCR of EADS Astrium GmbH will be described firstly before discussing different test applications and its requirements. Due to the fact that the available frequency spectrum and satellite orbits are both getting more and more crowded, the demands on satellite antennas using efficiently these resources are increasing. This implies more complex antenna structures with very stringent requirements on the antenna and payload tests. Finally, typical tests for antenna pattern and gain as well payload parameter measurements will be described. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Dual-Polarised Dielectric Near-Field Probe

    Page(s): 33 - 35
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (836 KB) |  | HTML iconHTML  

    This paper presents a novel dielectric near-field probe as an alternative for the conventional open-ended waveguide probes. The latter tend to be bulky in the mobile communication frequency bands (GSM 900 and GSM 1800). Furthermore they show significant interaction with the AUT as compared to the proposed dielectric probe. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • High Resolution Equivalent Source Current Calculation for Planar Antennas

    Page(s): 36 - 40
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (380 KB) |  | HTML iconHTML  

    A method is presented to calculate discrete equivalent source current distribution functions from measured electric near field distribution functions. The calculated distribution functions possess a high spatial resolution of about a tenth of the radiated wavelength and therefore permit insight into the functional details of the investigated DUT antennas. Several characteristic parameter can be obtained from the evaluation of the calculated distribution functions. Some examples are presented for linear microstrip antenna arrays. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analysis and Measurement of Reflector Antennas in the MM-Wave Frequency Range

    Page(s): 41 - 44
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (611 KB) |  | HTML iconHTML  

    For the ADMIRALS study of ESA/ESTEC, performed in 2000 - 2002 and subsequent mm-wave studies in 2003 - 2005, a Representative Test Object (RTO) was designed and built to validate the antenna measurement performance with a high gain reflector antenna at 203, 322 and 503 GHz. The RTO mainly contains out of an offset reflector antenna with 1.5 in reflector diameter and is related to future remote sensing antennas as FIRST, MASTER or HERSCHEL/PLANCK. For assessment of measurement results, the RTO was theoretically analyzed with the simulation tool GRASP. For improvement of the simulation model, primary feed and surface contour data of the reflector - measured at the feed as well as reflector manufacturer - were taken into account within the simulations. Within further simulations, reflector deformation effects due to the mounting configuration regarding the reflector backing structure of the RTO reflector could be identified with additional surface measurements of the RTO reflector. Additional optical measurements were performed with a highly accurate laser tracker system and measurement technology. The accuracy of these measurements could be identified with 10 .. 20 mum. This work was finished in 2005 and the results are described in this paper. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Antenna Diversity for Improving the BER in Mobile Digital Radio Reception Especially in Areas with Dense Foliage

    Page(s): 45 - 48
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (623 KB) |  | HTML iconHTML  

    An antenna diversity for satellite digital audio radio systems (SDARS) was implemented as a first hardware demonstrator and tested. Proof is shown that for critical reception scenarios for example underneath dense foliage or in multipath situations between high buildings the antenna diversity yields a significant reduction of the bit error rate (BER). Full diversity function is achieved with no additional effort in mounting and required space for the antennas. Only one antenna line is used and one tuner as in conventional single arm receiving systems is employed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A 3-Port Antenna for MIMO applications

    Page(s): 49 - 52
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1592 KB) |  | HTML iconHTML  

    As well known, the capacity of a radio frequency channel can be enlarged by multiple input multiple output (MIMO) antenna system. By using identical antennas with the same orientation, a certain antenna distance must be respected for achieving the full MIMO gain. On mobile terminals, usually only a limited surface area for antennas is available. Therefore multiport antennas with small dimensions are requested, which offer sufficient decoupling between the ports. The present paper describes a 3-port antenna, operating at 5.6 GHz, which can be used e.g. for MIMO-WLAN applications. The design is outlined and simulated and measured results are given. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Interference Suppression Technique for Diversity Selection Combining in an Indoor Environment

    Page(s): 53 - 57
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (695 KB) |  | HTML iconHTML  

    In this paper a new diversity selection combining scheme called SSB (simplified switched beam) is given, as well as its test-bed implementation. SSB has apparent advantage in terms of size, power and complexity since it only requires one RF front-end and very few additional components. Furthermore, an interference suppression technique is designed, which can effectively mitigate the disturbance on correct diversity selection caused by interference. The intensive measurements made in an indoor environment show that this test-bed can closely approach the theoretical prediction on SNR gain and AF (amount of fading) made in [4] and [9] previously. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • MIMO antenna system based on orthogonality of the characteristic modes of a mobile device

    Page(s): 58 - 62
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (249 KB) |  | HTML iconHTML  

    A novel concept is introduced to realize a multiple antenna system on a small mobile device by coupling to its characteristic modes. According to the theory, the current density on the chassis of a mobile device is the superposition of characteristic mode current densities which have unique resonance frequencies. There are some interesting frequency ranges where more than a single mode is near resonance, i.e. may be appreciably excited and contributes to the overall radiation. For a selective excitation of the characteristic modes near to their resonant frequencies, an arrangement of 4 capacitive couplers and a feed network can be introduced. This type of excitation circumvents crosstalk between the input ports and ensures mutually orthogonal radiation patterns. The main problem to be solved is the simultaneous matching of all modes. The easiest approach is the method of a balanced mismatch (minimization of the maximum mode reflection coefficient). Advanced methods combine this idea with a systematic modification of the parameters of the characteristic modes. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Decoupling and Matching Network for Miniaturised 3-Port Antenna Arrays Based on 180° Couplers

    Page(s): 63 - 66
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (478 KB) |  | HTML iconHTML  

    In ordinary antenna arrays the spacing between radiators is usually chosen lambda/2. In order to use antenna arrays in small mobile platforms, the overall dimensions and hence the radiator separation must be reduced, which aggravates the problem of mutual coupling between radiators. Results are highly distorted beam patterns and greatly reduced radiation efficiency. We propose a simple method to design a decoupling and matching network for a three element antenna array with a radiator separation of lambda/4, which excites the orthogonal eigenmodes of radiation of the antenna array. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Antennas for UWB-Systems

    Page(s): 67 - 71
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (3680 KB) |  | HTML iconHTML  

    The number of antennas is nearly unlimited because almost any piece of metallization or dielectric can radiate an electromagnetic wave. The problem to solve is that this radiation is properly what is required. Basic principles for ultra-wide-band (UWB) radiation are presented and discussed in this paper. The discussion is based on definitions for the characterization of UWB antennas. Basic principles for UWB radiation are discussed. For each of these principles an example UWB antenna is presented. The final outcome is that there are also a number of UWB antennas, but not each one is suited for any application. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Directive Ultra-Wideband Dipole Antenna with Dielectric Rod and Reflector

    Page(s): 72 - 75
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1689 KB) |  | HTML iconHTML  

    A directive ultra-wideband (UWB) antenna exhibiting a gain of more than 7 dBi in the whole FCC UWB frequency band is presented. The excitation of the so called dipole mode on the rod is achieved by a biconical dipole. Placing this configuration in some distance to a reflector results in a flat gain curve. Besides an input reflection of better than -10 dB from 3 up to 20 GHz, this novel antenna has an excellent transient behavior over a wide azimuth angle, whereas the dimensions can be kept very compact. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Double-fed Wideband Printed Monopole Antenna

    Page(s): 76 - 80
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (456 KB) |  | HTML iconHTML  

    A double-fed printed monopole antenna having a wideband characteristic is presented. The monopole is rectangular in shape and is fed by a 50 ohms two-branch microstrip line. The antenna is designed and prototyped on a FR4 substrate. Both the simulated and measured results for impedance bandwidth are presented together with measured radiation patterns. The impedance bandwidth of the antenna is 2.2 GHz to 7.5 GHz covering all WLAN bands and frequencies in between. The antenna possesses approximately.omni-directional radiation properties throughout this bandwidth. It is easily fabricated using low-cost printed circuit technology. In addition this antenna is mechanically stable and readily Integratable with various mobile and portable devices. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • UWB Antenna Transfer Property Characterization by FDTD Simulations

    Page(s): 81 - 85
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (486 KB) |  | HTML iconHTML  

    In this paper the characteristics of different small planar omni-directional type antennas are studied in order to determine their suitability for ultra-wideband operation. The antennas are characterized in terms of their transfer properties in both the time and frequency domain. The antenna characteristics in the principal radiation planes are visually presented as colour scaled plots versus time or frequency - making it easy to make comparisons between different antenna types. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optimizing Multiband Antennas Using Simulated Annealing

    Page(s): 86 - 90
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (359 KB) |  | HTML iconHTML  

    The increasing demand for wireless communication services makes it necessary to use several frequency bands with a single device such as a mobile phone or a laptop computer. Consequently, antenna functionalities must be available in the various frequency bands and the ideal case is to have a single multiband antenna, which works at the desired frequencies. The design of multiband antennas is a challenging problem and in this work, simulated annealing is used as a powerful optimization method, which controls the design flow of such antennas. In order to evaluate the antenna characteristics of the various antenna realizations within the design process, a powerful integral equation technique accelerated by the multilevel fast multipole method is used. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Antenna Modeling with the Hybrid Finite Element - Boundary Integral - Multilevel Fast Multipole - Uniform Geometrical Theory of Diffraction Method

    Page(s): 91 - 95
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1272 KB) |  | HTML iconHTML  

    In many antenna applications, the environment of the radiating system has a significant effect on the overall radiation of the antenna and should be taken into account in the simulations. The involved objects are often electrically very large, so that numerical techniques combining ray optical asymptotic methods are preferred to handle such configurations. In this contribution, simulation results of electromagnetic radiation problems including environment effects are presented, using the recently developed hybrid method, which combines the Uniform Geometrical Theory of Diffraction (UTD) with the Finite Element Boundary Integral (FEBI) technique and with the Multilevel Fast Multipole Method (MLFMM). Electrically large and simple flat objects in the neighborhood of antennas are treated with UTD, providing full electromagnetic coupling with composite metallic/dielectric arbitrarily shaped FEB! objects. Thereby, double diffracted high-frequency fields on pairs of straight metallic non-coplanar and skewed edges are taken into account using the hard and soft scalar diffraction coefficients of UTD. Also, near-field computations in the postprocessing stage are efficiently accelerated by MLFMM, where ray optical contributions due to the presence of electrically large objects are taken into account according to the hybridization of MLFMM with UTD. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.