A novel dual-fed, self-diplexing PIFA and RF front-end (PIN-DF/sup 2/-PIFA)

A compact multiband PIFA (planar inverted-F antenna) occupying a very small volume of less than 0.8 cm 3 in the mobile phone for GSM/DCS/PCS/UMTS operation is presented. The PIFA uses a single resonant path only, which is close to about one-eighth wavelength at 900 MHz. A coupling feed, different from the conventional direct feed, is proposed to excite the PIFA. In this case, the large input impedance at 900 and 1900 MHz can be greatly decreased, making it promising to excite two operating bands at about 900 and 1900 MHz to cover the desired multiband operation. Good radiation characteristics for frequencies over the operating bands are also obtained. The occupied volume of the proposed multiband PIFA is about the smallest among the reported internal multiband mobile phone antennas. ABSTRACT: UWB cross semi-elliptic monopole antenna with a dual-band rejected characteristic is presented and experimentally studied. The proposed cross bevel-rectangular monopole antenna is embedded with four small h-shaped slots; it produces a design of dualband rejected characteristics and maintains omnidirection radiation. This technique is suitable for creating multiwideband antenna or ultrawideband (UWB) antenna with dual-rejected band. And the proposed antenna with good omnidirection characteristic is also maintained. Details of the results for the proposed antenna are presented and discussed in this study.

Section: Introductionmentioning

confidence: 79%

“…Recently, the monopole antenna has been renewal of interest about to create ultra-wideband (UWB) antenna, it is because of which has very wide impedance bandwidth, omnidirectional radiation pattern, and simple structure [1][2][3][4]. However, the planar monopole antenna has non-omnidirectional radiation pattern at higher frequency.…”

Section: Introductionmentioning

confidence: 99%

Compact multiband PIFA with a coupling feed for internal mobile phone antenna

Wong

Huang

2008

“…The use of an external matching circuitry has also been applied [6][7][8][9]. This technique is promising to enhance the bandwidth at either the 900 or 1800 MHz band or both the 900 and 1800 MHz bands.…”

Section: Introductionmentioning

confidence: 99%

Bandwidth‐enhanced internal PIFA with a coupling feed for quad‐band operation in the mobile phone

Huang

2008

with a lengthened or shortened␦, the rejection slope at the upper frequency can be enhanced. A 4th order 10% FBW Chebyshev filter was designed at 5 GHz with additional rejection of 23 dB at 6 GHz. Since the overall filter resonator length remains unchanged, the improvement in performance does not compromise on circuit size. BANDWIDTH-ENHANCED INTERNAL PIFA WITH A COUPLING FEED FOR QUAD-BAND OPERATION IN THE MOBILE PHONE

GSM850/900/1800/1900/UMTS coupled‐fed planar λ/8‐PIFA for internal mobile phone antenna

Chang¹

2009

higher harmonic suppressions with less number of periodic structures compared to the conventional DGS filter. EXPERIMENT AND RESULTSTo validate the proposed low pass filter, it was simulated and fabricated in the Taconic TLC with a relative permittivity e r ϭ 3.2 and a thickness h ϭ 0.787 mm. Figure 8(a) shows the photograph of the proposed low pass filter with compact size of 25 Ј 40 mm 2 . The measured results have shown a good agreement with the theoretical results. The experiment results demonstrate that the fabricated LPF has a 3 dB cut off frequency at 4.5 GHz and there is a shift of cutoff frequency of about 50 MHz. The insertion loss is low dB at the passband when measured and its stopband is well suppressed below 32-dB from 5.2 to 10 GHz. CONCLUSIONSIn this article, a novel compact microstrip low pass filter using elliptic DGS cells is presented. The novel H shape open stub increases the equivalent parallel capacitance to improve the outband suppression. An equivalent circuit model was given to depict the novel DGS filter. The proposed structure with main dimension parameters was analyzed as a design guide to fabricate the filter. The measurement results have shown good agreement with the theoretical results. The cutoff frequency response is sharp and insertion loss is low with stopband from 5.17 to 10 GHz, which was suppressed more than 32 dB. 2. F. Zhang and C. F. Li, Power divider with microstrip electromagnetic bandgap element for miniaturisation and harmonic rejection, Electron Lett 44 (2008), 422-424.