Internal shorted planar monopole antenna embedded with a resonant spiral slot for penta‐band mobile phone application

Abstract

Comparing the results in Table 1 it can be seen that satisfactory results are obtained by the CMM presented in this paper.When the outer conductors are the same size and characteristic impedances are both 50 ⍀, the comparison of cutoff frequency between novel and conventional TEM cell are presented in Table 2. Here, L equals 10 cm and I equals 2 cm.When L ϭ 10 cm, H ϭ 6 cm, I ϭ 2 cm, ϭ 60°, and the input power is 1 W, the electric field distribution of TEM mode in the novel TEM cell is shown in Figure 6. According to the definition of uniform field in IEC 61000-4-20, the uniform area in Figure 6 is 4.55 cm ϫ2.9 cm. In the conventional TEM cell which has the same cutoff frequency and length-width ratio, the uniform area is 5.10 cm ϫ 2.46 cm, smaller than that of the novel one. CONCLUSIONIn order to study the kinetics of microwave chemistry, new devices with a higher cutoff frequency and a larger area of uniform electromagnetic field are needed. In this paper, we propose a novel TEM cell to satisfy these conditions and used an analytical method based on a three-step conformal mapping to calculate the characteristic impedance of the TEM cell. Two methods were used to validate the analytical solution. First, the FEM numerical method was used to calculate the characteristic impedance. The comparison between the analytical and numerical calculation showed the analytic solution gave very precise results. Then, when the configuration of the TEM cell degenerated to a conventional TEM cell, the calculation of characteristic impedance agreed very well with the results previously published in the literatures. Further work, such as the calculation of the field distribution in a test tube and the design of taper connected with the coaxial line will be shown in the future. Analysis of asymmetric TEM cell and its optimum design of electric field distribution, IEE Proc 136 (1989), 191-194. 5. E. Costamagna and A. Fanni, Asymmetric TEM cell impedance calculation, IEE Proc 137 (1990), 318-320. 6. S.K. Das and B.N. Das, Analysis of the effects of septum thickness on impedance and fields of TEM mode inside an asymmetric TEM cell, IEE Proc-H 140 (1993), 347-353. ABSTRACT: An internal shorted planar monopole antenna embedded with a resonant spiral slot for GSM850/900/DCS/PCS/UMTS operation in the mobile phone is presented. The planar monopole is printed on an FR4 substrate of small size 10 ϫ 45 mm 2 , and a spiral slot of length 108 mm is embedded therein. The planar monopole is then placed above and perpendicular to the top edge, with a small distance of 7 mm, of the system ground plane of the mobile phone to operate as an internal antenna. A coupled feed printed on the top no-ground portion of the system circuit board is used to excite both the planar monopole and the spiral slot to generate two wide bands covering GSM850/900 and DCS/ PCS/UMTS operation, respectively. The antenna is also suitable to integrate with the associated electronic components, such as the speaker, to achieve a compact integration of the antenna inside the ...

Very‐small‐size printed loop antenna for GSM/DCS/PCS/UMTS operation in the mobile phone

“…portion. With the small lateral length, which is only about half of the width of general mobile phones, the loop antenna can be placed at around one of the corners of the top no-ground portion, leaving a large unoccupied region at the top of the circuit board to accommodate the possible elements like the speaker [14,15], the embedded digital camera [16], etc. This feature is obtained owing to the very small size of the printed loop antenna studied here, which is an advantage over the conventional internal mobile phone antennas which usually occupy the whole top portion of the mobile phone.…”

Small‐size coupled‐fed printed PIFA for internal eight‐band LTE/GSM/UMTS mobile phone antenna

“…The shaded region can be used to accommodate the nearby electronic components such as the loudspeaker [13][14][15] to allow compact integration of the proposed antenna inside the mobile phone; the results will be discussed in Figure 8 in Section 3.…”

Capacitively FED hybrid monopole/slot chip antenna for 2.5/3.5/5.5 GHz WiMAX operation in the mobile phone

“…However, in both designs, the two hybrid elements are separated and are not combined into one single element to achieve a compact antenna size. In [12], the hybrid antenna is achieved by embedding a 0.5-wavelength slot element [19,20] inside a monopole patch element, and GSM850/900/1800/1900/UMTS pentaband WWAN (wireless wide area network) operation [21] is obtained. We further apply this integration technique [12] in this study for two hybrid elements to achieve a compact hybrid antenna design on a small chip base (a thin FR4 substrate of small size used here) as a surface-mount element [22,23] for WiMAX operation in the mobile phone.…”