Design and Development of Ultra-Thin Monopole Antenna for WLAN and WiMAX Operations in the Next-Generation Laptop Computer

Purpose This paper aims to present a triple-band monopole antenna design of 0.2-mm thickness with an overall dimension of 21 × 8 mm2 for wireless local area network (WLAN)/worldwide interoperability for microwave access (WiMAX) multiple input and multiple output (MIMO) applications in the laptop computer. Design/methodology/approach It comprises three monopole radiating elements, namely, strip AD (inverted C), strip EG (inverted J) and strip FI (inverted U) along with two rectangular open-end tuning stubs, namely, “m” and “n” of size 1.5 × 0.9 mm2 and 1.8 × 0.9 mm2, respectively. The proposed structure is compact, cost-effective and easy to integrate inside the laptop computers. Findings This structure excites three WLAN (2.4/5.2/5.8 GHz) and three WiMAX (2.3/3.3/5.5 GHz) bands. The proposed antenna array elucidates that it has measured −10dB impedance bandwidth of 11.86 per cent (2.22-2.50) GHz in a lower band (f_l), 6.83 per cent (3.25-3.48) GHz in medium band (f_m) and 16.84 per cent (5.00-5.92) GHz in upper band (f_u). The measured gain and radiation efficiency are above 3.64dBi and 75 per cent, respectively, and isolation better than −20dB. The envelope correlation coefficient (ECC) is less than 0.004. The simulated and measured results are in good concurrence, which confirms the applicability of the proposed antenna array for MIMO applications in the laptop computer. Originality/value The proposed antenna is designed without using vias, reactive elements and matching circuits for excitation of WLAN/WiMAX bands in the laptop computers. The design also does not require any additional ground for mounting the antenna. Further, the antenna array, formed by using the same antenna design, does not need additional isolating elements and is designed in such a way that the system ground itself acts as an isolating element. The proposed antenna has a low profile and is ultra-thin, cost-effective and easy to manufacture and can be easily embedded inside the next-generation laptop computers.

Download Full-text

Safe and Sound: Designing the Vocal Smoke Detector

Ergonomics in Design The Quarterly of Human Factors Applications ◽

10.1518/106480408x333127 ◽

2008 ◽

Vol 16 (3) ◽

pp. 26-28

Author(s):

Rob Tannen ◽

Mathieu Turpault

Keyword(s):

Human Factors ◽

Development Process ◽

Smoke Detector ◽

Next Generation ◽

Design And Development ◽

Household Product ◽

Smoke Detectors ◽

Effective Design ◽

Human Factors Research

The design of the vocal smoke detector incorporated psychoacoustic research to more effectively waken children. It also provided an opportunity to examine and improve the usability of an often-overlooked but critical household product. Human factors research into existing smoke detectors identified ergonomic and interaction opportunities in installation and use, which were addressed by an effective design and development process. The result of this effort was not just an appealing and usable product but a next-generation smoke detector that enhances safety by design.

Download Full-text