In this article, a uniplanar printed PIFA (planar inverted‐F antenna) with a coupling feed for application as an internal laptop computer antenna for penta‐band WWAN (wireless wide area network) operation is presented. The proposed PIFA has a compact structure and can be easily printed on one side of a small 0.8‐mm thick FR4 substrate of size 11 × 59 mm2, making it very promising to be embedded inside the casing of the laptop computer, especially for the thin‐profile laptop computer. With the coplanar coupling feed, the large inductive input reactance of the PIFA at around 900 MHz is compensated, and dual‐resonance excitation for the antenna's lower band at about 900 MHz is obtained, which allows it to easily cover GSM850/900 operation. A wide operating band is also achieved for the antenna's upper band at about 1900 MHz, and a bandwidth of larger than 500 MHz is obtained to cover GSM1800/1900/UMTS operation. That is, the proposed PIFA covers all the five operating bands of GSM850/900/1800/1900/UMTS for WWAN operation. Details of the proposed PIFA are presented. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 549–554, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24084

A coupled‐fed PIFA (printed inverted‐F antenna) printed on a small‐size FR4 substrate promising for 2.4/5.2/5.8 GHz WLAN (wireless local area network) operation in the laptop computer is presented. When mounted at the top edge of the system ground plane or supporting metal frame of the laptop display, the PIFA shows a height of 9 mm and a small width of 7 mm only. With a narrow width, it is promising for more internal antennas to be mounted along the top edge of the supporting metal frame of the laptop display. The PIFA also shows a uniplanar structure, allowing it easy to fabricate, and is fed using a T‐shaped coupling strip, which leads to successful excitation of two wide operating bands to cover WLAN operation in the 2.4 GHz band and 5.2/5.8 GHz band. Details of the proposed PIFA are studied, and experimental and simulation results are presented. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1023–1028, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24206