KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Settings

Author: search.filters.author.Akkaraekthalin, P.

Search Results

Now showing 1 - 3 of 3
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    A handheld moisture content sensor using coupled-dipole antennas
    (2010-07-01)
    Mearnchu, J.
    ;
    Limpiti, T.
    ;
    Torrungrueng, D.
    ;
    Akkaraekthalin, P.
    ;
    Krairiksh, M.
    This paper presents an analysis and design of a handheld moisture content sensor. A dielectric property determination technique was used to measure the magnitudes of the reflection and the coupling coefficients of coupled-dipole antennas. These coefficients were plotted and their intersection determined to obtain the values of ε' <inf>r</inf> and ε" <inf>r</inf> (ε' <inf>r</inf> and ε" <inf>r</inf>, respectively, are the real and imaginary parts of the relative complex permittivity of the dielectric of interest). Moisture content measurements for paddy at various moisture content levels are shown. Comparison of measurements made by this technique with those made by conventional transmission measurement technique yielded a compensation scheme for error reduction. This sensor is useful for controlling the quality of paddy dried in a continuous microwave drying system process.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    A rhombic patch monopole antenna with modified minkowski fractal geometry for umts, wlan, and mobile wimax application
    (2009-01-01)
    Mahatthanajatuphat, C.
    ;
    Saleekaw, S.
    ;
    Akkaraekthalin, P.
    ;
    Krairiksh, M.
    This paper presents a rhombic patch monopole antenna applied with a technique of fractal geometry. The antenna has multiband operation in which the generator model, which is an initial model to create a fractal rhombic patch monopole, is inserted at each center side of a rhombic patch monopole antenna. Especially, a modified ground plane has been employed to improve input impedance bandwidth and high frequency radiation performance. The proposed antenna is designed and implemented to effectively support personal communication system (PCS 1.85-1.99 GHz), universal mobile telecommunication system (UMTS 1.92-2.17GHz), wireless local area network (WLAN), which usually operate in the 2.4GHz (2.4-2.484GHz) and 5.2/5.8GHz (5.15-5.35 GHz/5.725-5.825 GHz) bands, mobile worldwide interoperability for microwave access (Mobile WiMAX), and WiMAX, which operate in the 2.3/2.5 GHz (2.305-2.360 GHz/2.5-2.69 GHz) and 5.5 GHz (5.25-5.85 GHz) bands. The radiation patterns of the proposed antennas are similar to an omnidirectional radiation pattern. The properties of the antenna such as return losses, radiation patterns and gain are determined via numerical simulation and measurement.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    A bidirectional multiband antenna with modified fractal slot fed by CPW
    (2009-01-01)
    Mahatthanajatuphat, C.
    ;
    Akkaraekthalin, P.
    ;
    Saleekaw, S.
    ;
    Krairiksh, M.
    This paper presents a multiband slot antenna with modifying fractal geometry fed by coplanar waveguide (CPW) transmission line. The presented antenna has been designed by modifying an inner fractal patch of the antenna to operate at multiple resonant frequencies, which effectively supports the digital communication system (DCS 1.71-1.88 GHz), worldwide interoperability for microwave access (WiMAX 3.30-3.80 GHz), IMT advanced system or forth generation mobile communication system (3.40-4.2GHz), and wireless local area network (WLAN 5.15-5.35GHz). Manifestly, it has been found that the radiation patterns of the presented antenna are still similarly to the bidirectional radiation pattern at all operating frequencies. The properties of the antennas, for instance, return losses, radiation patterns and gain are determined via numerical simulation and measurement.