天線工程期中報告論文研討 : Yu-Chun Lu ,Yei-Shen Wu , Chi-Tsung

Chiu,and Yi-Cheng Lin “A Novel Compact Design of USB Dongle Antenna for Bluetooth Applications”, RSW2009

報告人 : 碩研通訊一甲 MA133101 郭士賓

Southern Taiwan UniversitySouthern Taiwan University Department of Electronic Engineering

ABSTRACT

　 This paper presents a compact design of printed wire inverted-F antenna with parasitic ground extrusion on a low cost FR4 PCB substrate. An antenna area of 6.5mm × 12mm is achieved in a USB dongle module with total area of 12mm × 20mm, operated at 2.4 GHz.The experimental results from the fabricated prototypes are also included.

　 In general, a small antenna suffers a narrow bandwidth performance.In this study, we successfully enhance the antenna bandwidth by using two resonances coupling between the feeding strip and the grounded parasitic element.

2RSW2009 Yu-Chun Lu ,Yei-Shen Wu , Chi-Tsung Chiu,and Yi-Cheng Lin

ANTENNA DESIGN

　 In the optimized design, the resultant antenna area of 6.5mm x 12mm and total dongle size of 20mm x 12 mm is achieved for 2.4 GHz operation.

　 The proposed antenna is implemented on a FR-4 substrate of dielectric constant εr = 4.4 and thickness h = 0.6mm with the microstrip width Wf=1.1mm for a 50-ohm input impedance.

3RSW2009 Yu-Chun Lu ,Yei-Shen Wu , Chi-Tsung Chiu,and Yi-Cheng Lin

GEOMETRY OF PROPOSED ANTENNA

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　 The dimensions and parameters of the antenna are listed as follow: L=20mm, W=12mm, Lg=13.5mm, S=3mm, G1=U1=6.5mm, U2=5.75mm, U3=4.9mm, U4=4.5mm, U5=4mm, G2=6.9mm, G3=4.9mm, G4=5.25mm, and G5=3.75mm.

RSW2009 Yu-Chun Lu ,Yei-Shen Wu , Chi-Tsung Chiu,and Yi-Cheng Lin

SIMULATION AND MEASUREMENTSReturn Loss

5RSW2009 Yu-Chun Lu ,Yei-Shen Wu , Chi-Tsung Chiu,and Yi-Cheng Lin

　 The miniaturized USB dongles can be seen that the simulated results have about 200MHz bandwidth while the measurement results have a frequency shift to higher frequency band with a merely seen second resonance located at 2.6GHz.

6RSW2009 Yu-Chun Lu ,Yei-Shen Wu , Chi-Tsung Chiu,and Yi-Cheng Lin

SIMULATION AND MEASUREMENTSRadiation Patterns

　 In Fig. (a) and (b) the antenna gain is measured to be about -3 dBi in both planes at 2.45GHz.

E-plane

7RSW2009 Yu-Chun Lu ,Yei-Shen Wu , Chi-Tsung Chiu,and Yi-Cheng Lin

　 The measured patterns of the antenna agree with the simulated ones in shape but not in the gain level. This is mainly due to the frequency up-shift of the lower band.

H-plane

SIMULATION AND MEASUREMENTSRadiation Patterns

RSW2009 Yu-Chun Lu ,Yei-Shen Wu , Chi-Tsung Chiu,and Yi-Cheng Lin

SIMULATION AND MEASUREMENTSCurrent Distributions

　 Surface current density distribution is clearly shown that the lower frequency resonance is controlled by the grounded parasitic strip, while the upper frequency resonance is controlled by the WIFA at the signal line layer.

2.38GHz 2.51GHz

9RSW2009 Yu-Chun Lu ,Yei-Shen Wu , Chi-Tsung Chiu,and Yi-Cheng Lin

SIMULATION AND MEASUREMENTSEffects of shorting position S

　 The simulated return loss as a function of frequencies with various value of S. It can be observed that the impedance matching level and resonant frequency varies with different values of S.

　 A wideband miniaturized antenna for USB dongle application has been proposed. The antenna is successfully designed, implemented, and measured.

　 By introducing another metal strip extending from the ground plane a second resonance could be generated to achieve a dual band antenna.

　 The resultant antenna area is reduced to an area of 6.5mm x 12mm and total dongle size of 20mm x 12 mm for 2.4 GHz operation with BlueTooth applications.

10RSW2009 Yu-Chun Lu ,Yei-Shen Wu , Chi-Tsung Chiu,and Yi-Cheng Lin

CONCLUSIONS

REFERENCES

W.-C. Su and K.-L. Wong; “Internal PIFAs for UMTS/WLAN/WiMAX multi-network operation for a USB dongle”, Microwave Opt. Tech. Lett, Vol. 48, No. 11, pp. 2249-2253, 2006

M. Ali and G. J. Hayes, “Small printed integrated inverted-F antenna for Bluetooth application”, Microwave Opt Tech. Lett, Vol. 33, No. 5, pp. 347-349, 2002

C.-H Wu., K.-L. Wong, Y.-C. Lin, S.-W. Su, “Internal shorted monopole antenna for the watch-type wireless communication device for Bluetooth operation”, Microwave Opt Tech. Lett, Vol. 49, No. 4, pp. 942-946, 2007

B. S. Yildirim, “Low-Profile and Planar Antenna Suitable for WLAN/Bluetooth and UWB Applications”, IEEE Antennas Wireless Propagat. Lett, Vol. 5, pp. 438-441, 2006

H. Mosallaei and K. Sarabandi, “Antenna miniaturization and bandwidth enhancement using a reactive impedance surface substrate,” IEEE Trans. Antennas Propag., Vol. 52, No. 9, pp. 2403-2414, 2004

H. A. Wheeler, “Fundamental limitations of small antennas”, Proceedings of the IRE, Vol. 35, No. 12, pp. 1479-1484, 1947.

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心得

　　　對於本文看似簡單的幾何圖形，卻有著那麼多的考量與參數才能完成天線，對於天線的運作流程還是保持著許多疑問，因為沒做過所以不知道也不清楚，只好依文獻的述說來完成此次的報告。　　　　

　　　而本次的報告製作過程中，因許多名詞沒接觸過所以造成了一些困難，而在這些困難中也了解到每個研究者要有能力發表一篇論文需要花費的時間與精力，另外因語言上的困難怕因翻譯成中文有失原意 , 所以大部分以截錄與編修的方式進行排版，在日後我會在繼續努力加強語言能力，儘可能在期末報告用我所知道的與自己對論文的了解，來詮釋另一份報告的製作。