acm - an acm publication

2006 - April

  • A comparison the performances of linear and planar array of the four patchs antennas by the software matlab
    A linear array is a simple configuration and commonly used, however it is essential to investigate its performances.There are four basic factors that influence on performances of an array patches antennas: spacing between patches, number of patches in the array, amplitude distribution, and excitation phase, all these parameters will be varied to find the optimal configuration.This paper is consecrated to the variation of the excitation phase, and the other factors are fixed, what is going to permit us to scanning the radiation pattern of a linear array of four rectangular patches microstrip antennas in the E-plane and in the H-plane, without resorting to a mechanical displacement of this array [1]. The effect on the direction of the main beam of those arrays (linear and planar) will be studied. We are going to compare our theory used and programmed in MATLAB by one simulations executed in the PCAAD (Personal Computer Aided Antennas Design) software [2].However, we are going to explore the radiation pattern by the variation of the excitation phase of patches of a square array for four rectangular microstrip patches antennas array, as we takes the same elements of the previous linear array[3], [4], and we are going to put them under shape of a planar square array.
  • Electronic scanning in space of the planar array of four patch antennas
    The rectangular patch antenna is set to play a significant role in the development of the next-generation wireless communication systems. The purpose of this report is to provide the design of the rectangular patch antenna system by studying the performance of patch antenna array, and to achieve the electronic scanning in space of the radiation patterns by a four rectangular patch antennas plan array. The designed patch antenna square array will have an array of four elements and its performance will be evaluated in terms of radiation patterns.Results given by the MATLAB and PCAAD (Personal Computer Aided Antenna Design) software will be tabulated and antenna radiation patterns will be plotted for discussion before wrapping up with a conclusion and suggestion on future developments.
  • Corporate renewal engines
    The great, long-living companies are able to adapt to tectonic market shifts and historical changes while crossing different technological epochs. Several books have captured historical and anecdotal evidence about such extraordinary businesses, while we have a few crisp and simple business models of these great companies.