List of subject articles Electromagnetic, Antenna and Propagation


    • Open Access Article

      1 - A 2-bit Full Comparator Design with Minimum Quantum Cost Function in Quantum-Dot Cellular Automata
      Davoud Bahrepour Negin Maroufi
      In recent years, reduction of the complementary metal-oxide-semiconductor (CMOS) circuit feature size has caused significant challenges, such as current loss and leakage, and high power consumption. Therefore, further reduction of the size of CMOS technology is not feas Full Text
      In recent years, reduction of the complementary metal-oxide-semiconductor (CMOS) circuit feature size has caused significant challenges, such as current loss and leakage, and high power consumption. Therefore, further reduction of the size of CMOS technology is not feasible. Quantum-dot cellular automata (QCA) is an emerging technology at the nanoscale, which can utilize for designing computers and very-large-scale integration (VLSI) circuits in the near future. QCA technology makes it possible to design low-power, high-performance, and area-efficient logical circuits. A comparator function is a digital logical function, which compares whether a bit is greater than, smaller than or equal to the other bit or not (half comparator). Full comparator has a third input, which shows the result of the previous step. Half and full comparators play an essential role in CPU architecture. In this paper, a full comparator circuit based on the QCA and a new quantum cost function is proposed. Besides a 2-bit comparator is presented based on the introduced full comparator. Using the new quantum cost function the proposed full comparator design is compared with the previously presented designs in terms of area, delay, and complexity. Comparisons show that the proposed design has less area and delay and therefore, it is more suitable for utilizing in CPU design. Manuscript Document
    • Open Access Article

      2 - Standard Deviation Characterization of a Small Size Reverberation Chamber by Using Full-wave Simulation and E-Field Probe
      ehsan poodineh Farhad Ghorbani Reza Asadi Hadi Aliakbarian
      Reverberation Chamber (RC) is a new type of measurement equipment used in electromagnetic compatibility and antenna tests and capable to produce an almost uniform electric filed inside a Working Volume (WV). In this paper, the field uniformity of an actual small size RC Full Text
      Reverberation Chamber (RC) is a new type of measurement equipment used in electromagnetic compatibility and antenna tests and capable to produce an almost uniform electric filed inside a Working Volume (WV). In this paper, the field uniformity of an actual small size RC is studied. At first, the mode density of the chamber which should be larger than unity is investigated. In the next step, the Standard Deviation (SD) of a small size RC, as a field uniformity criterion is investigated in an existing RC. A highly detailed three-dimensional model of chamber including its stirrers, antenna, WV, and its door create to verify the field uniformity of a RTS60 reverberation chamber. The removal of reverberation chamber’s stirrers shows that they have a direct effect on the uniformity of field. As the stirrer moves during the test, the effect of three different position of stirrer on the field uniformity is investigated. The transmission antenna, as an important component of these rooms, is simulated and investigated separately. The reflection coefficient of that antenna fit the working frequency band of the chamber. In a real scenario, the SD of the chamber is measured by using an electric field probe. A comparison between the simulation and measurement also is done in order to confirm the uniformity of the electric fields. Manuscript Document