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

Abstract

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.

Compact triple‐band PIFA with high bandwidth and gain for multiple mobile services

“…The obtained patterns are similar, ensuring the described characteristics of each antenna and within the acceptable standard [2]. Again, the obtained antenna gain is acceptable for practical applications [22]. The obtained radiation patterns in Figure 9(a,b,e,c), showed similar radiation patterns in both low and high frequency bands [23].…”

“…The obtained patterns are similar, ensuring the described characteristics of each antenna and within the acceptable standard . Again, the obtained antenna gain is acceptable for practical applications .…”

Small‐size internal eight‐band LTE/WWAN mobile phone antenna with internal distributed LC matching circuit

“…Recently, it has been demonstrated that by using a coupling feed, the type of planar inverted‐F antenna (PIFA) with no back ground plane for WWAN operation can have dual‐resonance excitation in the antenna's lower band at about 900 MHz [ 1–6] or excite its 1/8‐wavelength resonant mode as the antenna's lowest resonant mode [7–9]. The former leads to a wide lower band to cover the GSM850/900 operation (824–960 MHz) for the PIFA without increasing its occupied volume, while the latter results in a compact size for the PIFA to operate at about 900 MHz.…”

A frequency reconfigurable planar inverted‐F antenna for WWAN mobile handset applications

“…PIFA structures for covering the penta‐band must increase height of the antenna . In , a hybrid feed (slot coupled feed and capacitively coupled feed) antenna used three metallic layers that consist of two PIFAs and an open slot antenna, which increases the complexity.…”

“…In , a hybrid feed (slot coupled feed and capacitively coupled feed) antenna used three metallic layers that consist of two PIFAs and an open slot antenna, which increases the complexity. In , a wide operating band covering the frequency range of 824–960 MHz for the GSM850/900 operation was achieved by incorporating a coupled‐fed structure and an inductive shorting strip. Nevertheless, coupled‐fed PIFAs have a height of 5.8 mm or more.…”