A novel, very low profile, dual band inverted ‘E’ monopole antenna for wireless applications in the laptop computer

Abstract

A novel, very low profile and ultra-thin inverted 'E' shaped monopole antenna for WLAN/WiMAX applications in the laptop computer is presented. The thickness of the antenna is only 0.2 mm and is designed using only a pure copper strip of size 20 × 6 mm 2. The innovation of the design is miniaturized size and wider impedance bandwidth in dual band operation using two monopole radiating strips namely RS (inverted J) and PQ (inverted Z) along with open ended vertical tuning stub of size 4.5 × 1 mm 2. The measured impedance bandwidth spanned as 11.24% (2.35-2.63) GHz in a lower band (F l) and 18.78% (4.92-5.94) GHz in the upper band (F u) for VSWR < 2 and covers 2.4/5.2/5.8 GHz WLAN and 5.5 GHz WiMAX bands. The presented antenna has proved excellent radiation performance, including nearly omnidirectional patterns, a stable gain of around 4 dBi and an excellent efficiency of around 90% in F l and F u bands. This confirms the applicability for WLAN/WiMAX applications in the prominent ultra-thin laptop computers.

Multiband , miniaturized, maze shaped antenna with an air‐gap for wireless applications

“…From Table 5, it can be observed that the proposed antenna has the following features: Unlike to all existing state of arts, 1‐24 the proposed antenna is simple in design, compact and has dimensions of only 6 × 4 mm 2 , thus it can reduce the space required for mounting the antenna inside an actual laptop computers. Unlike those reported in References 16, 18, 19, the proposed antenna can operate within the desired bands of interest without using any additional lumped elements (inductors, capacitors etc. ), 3‐D structures and added holes or vias. Compared with References 1–5, 8, 9, 16, 18–20 the proposed antenna is suitable for different sizes of laptops and other portable devices. Unlike References 8, 9, 18, and the proposed antenna has exhibited broader fractional impedance bandwidths of 6.5% and 16% across the two operating bands. Compared with those in References 1, 4, 5, 11, 14, 21, 23, and the gain of the proposed antenna is above 3 dBi across all the operating bands. The proposed antenna can cover both the fundamental 2.4 and 5 GHz bands, unlike References 1–3, 7, 12. The proposed antenna does not require additional ground plane for affixing the antenna to system ground, unlike Reference 11 Unlike References 4, 5, 13, and the proposed antenna does not use expensive substrate. …”

“…This poses a good challenge to antenna designers in terms of design, fabrication, and reliability with respect to size, mounting, and cost. From the available open‐literature, extensive research work has been carried out on antenna miniaturization in terms of novel structures and antenna performances 1‐24 …”

“…However, the aforementioned antennas have used expensive Roger RT‐Duroid and Taconic TLY‐5‐0620 substrates, respectively, which may substantially increase the manufacturing cost. Thus, the method of designing antennas without using any lossy substrate while achieving good radiation performances have been studied 6‐8 . Here, the monopole antennas in References 6, 7 are designed using only a 0.035 mm thick copper strip, and 7 operates across the entire WLAN 5GHz band.…”

“…Thus, the method of designing antennas without using any lossy substrate while achieving good radiation performances have been studied 6‐8 . Here, the monopole antennas in References 6, 7 are designed using only a 0.035 mm thick copper strip, and 7 operates across the entire WLAN 5GHz band. As for the work reported in Reference 8, the antenna is made from a flat 0.3 mm thick copper‐nickel zinc alloy plate (size 18.7 × 32.5 mm 2 ), and it was bent into a compact structure of dimension 32.5 × 7 × 3.7 mm 3 , to excite both the WLAN 2.4 and 5 GHz bands.…”

Development of “ H‐Shaped ” monopole antenna for IEEE 802.11a and HIPERLAN 2 applications in the laptop computer

“…Gain and radiation efficiency of proposed antenna are calculated as follows:The gain is calculated using Friss formula as given below 33 : where, G 2 (dB) and G 1 (dB) are gain of the proposed and reference antenna, respectively, r is the distance between reference and proposed antenna, and p 2 and p 1 are the received and transmitted power of the proposed and reference antenna, respectively.…”