March 2004

Communications Research LaboratorySlide1Submission

doc.:IEEE802.15-04-0114-00-003a

Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANS)Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANS)

Submission Title: [Wideband Antenna with Dual Frequency for UWB System]Date Submitted: [March 2004]Source: [Yuko Rikuta, Ryuji Kohno] Company [Communications Research Laboratory (CRL)] Connector’s Address [3-4, Hikarino-oka, Yokusuka, 239-0847, Japan] Voice: [+81-46-847-5086], FAX: [+81-46-847-5431] E-mail: [rikuta@crl.go.jp, kohno@crl.go.jp] Re: [IEEE P802.15 Alternative PHY Call for Proposals, IEEE P802.15-02/327r7]Abstract: [This presentation is Introduction to the Wideband Antenna with Dual Frequency for UWB system. This novel monopole antenna consists of two connected planar elements.]Purpose: [Wideband Antenna with Dual Frequency for 802.15.TG3a]Notice: [This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.]Release: [The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15.]

March 2004

Communications Research LaboratorySlide2Submission

doc.:IEEE802.15-04-0114-00-003a

Wideband AntennaWideband Antennawith Dual Frequency for UWB Systemwith Dual Frequency for UWB System

Yuko Rikuta Ryuji KohnoYuko Rikuta Ryuji KohnoCommunications Research Laboratory, JapanCommunications Research Laboratory, Japan

Background Planar monopole antenna Geometry of analysis antenna model Antenna characteristics Conclusion

March 2004

Communications Research LaboratorySlide3Submission

doc.:IEEE802.15-04-0114-00-003a

Background (1)Background (1)

UWB Antennas (3D)-Double Ridged Guided Horn Antenna-Log periodic Antenna-Monocone-like Antenna etc.

UWB Antennas (2D)-Fractal Antenna-Vivaldi Antenna-Planar Dipole Antenna etc.

DRGHA

These antennas are covering 3.1~10.6GHz for UWB System.

March 2004

Communications Research LaboratorySlide4Submission

doc.:IEEE802.15-04-0114-00-003a

Background (2)Background (2)Ultra Wideband Antenna for UWB System

Ultra Wideband system covers the frequency bands

of 3.1~10.6GHz.

Need to suppress the interference where other systems exists

Wideband antenna and dual frequency

Single-band Multi-band

N divisionP

ower

　S

pect

rum

31 2 4 5 6 7 8 9 10 11 f [GHz]

5 GHz W-LAN

Dual- or Triple-band

UWB antenna can be applied to any band segmentations, such as single-, dual- and multi-bands.

March 2004

Communications Research LaboratorySlide5Submission

doc.:IEEE802.15-04-0114-00-003a

Background (3)Background (3)

To operate two frequencies by using two antennas makes the size of antenna installation larger.

Reducing the size is necessary.

Antennas with dual frequency

-radiation element + parasitic element

-two-layered top loaded monopole antenna

etc.

These antennas are suitable for two narrowband applications.

These antennas are suitable for two narrowband applications.

March 2004

Communications Research LaboratorySlide6Submission

doc.:IEEE802.15-04-0114-00-003a

Background (4)Background (4)Requirement for Ultra-wideband antenna

• Small size• Easy for fabrication• Return Loss characteristics : RL<-10dB• VSWR characteristics : VSWR<3• Radiation pattern : omni directional pattern• Gain characteristics : Gain>2dBi

• Antenna with dual frequency• Broadband characteristics

＋＋ Divides UWB frequency band

into 2 sub-bands

March 2004

Communications Research LaboratorySlide7Submission

doc.:IEEE802.15-04-0114-00-003a

12

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0

2 4 6 8 10

Ret

urn

Los

s [d

B]

Frequency [GHz]

monopolew=4w=8w=12w=16w=20

Planar Monopole AntennaPlanar Monopole Antenna

W

H=20mm

g

Bandwidths of each resonant frequency are changed by the antenna width.

y

z

x

March 2004

Communications Research LaboratorySlide8Submission

doc.:IEEE802.15-04-0114-00-003a

<xy plane> <zx plane>

( H=20mm, W=12mm )3.04~6.54GHz

Omni-directional pattern in horizontal plane can be obtained.

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Ret

urn

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s [d

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Frequency [GHz]

w=12

VSWR=2

Radiation pattern of planar monopoleRadiation pattern of planar monopole

March 2004

Communications Research LaboratorySlide9Submission

doc.:IEEE802.15-04-0114-00-003a

Monopole Antenna with Dual FrequencyMonopole Antenna with Dual Frequency

Cell size: x,y=1mm z=0.5mm

FDTD parameter

Iteration steps : 5000

ABC : PML 8 layer

Input： Gaussian Pulse

Upper : Rectangle element

(connected with lower)

Lower : Rectangle element

(Planar monopole antenna)

Feed

W

Hu

Hl

z

g

March 2004

Communications Research LaboratorySlide10Submission

doc.:IEEE802.15-04-0114-00-003a

Planar monopole and novel planar monopolePlanar monopole and novel planar monopole

Resonant frequency is divided to two resonant frequencies by adding slit to planar monopole.

Resonant frequency is divided to two resonant frequencies by adding slit to planar monopole.

novel planar

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Frequency [GHz]

planar

WHu

Hl

z

g

W

H

g

(a) Novel Planar Monopole (b) Planar Monopole

March 2004

Communications Research LaboratorySlide11Submission

doc.:IEEE802.15-04-0114-00-003a

Current distribution per antenna structureCurrent distribution per antenna structure

<planar monopole>

novel planar monopole

novel planar

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Frequency [GHz]

planarmonopole

<lower frequency> <higher frequency>

dB

dB dB

<monopole>

dB

March 2004

Communications Research LaboratorySlide12Submission

doc.:IEEE802.15-04-0114-00-003a

Return Loss characteristics of example antennaReturn Loss characteristics of example antenna

Wide bandwidth with dual frequency can be achieved.Return Loss level is almost 0dB at around 5~6GHz.

W

Hu

Hl

z

g

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Frequency [GHz]

March 2004

Communications Research LaboratorySlide13Submission

doc.:IEEE802.15-04-0114-00-003a

Radiation Pattern (xy) of example antennaRadiation Pattern (xy) of example antenna

•omni-directional pattern•Gain = 2.2-5.2dBi

y

z

x

March 2004

Communications Research LaboratorySlide14Submission

doc.:IEEE802.15-04-0114-00-003a

Radiation Pattern (yz) of example antennaRadiation Pattern (yz) of example antenna

y

z

x

omni-directional pattern in horizontal plane

March 2004

Communications Research LaboratorySlide15Submission

doc.:IEEE802.15-04-0114-00-003a

Radiation Pattern (zx) of example antennaRadiation Pattern (zx) of example antenna

y

z

x

omni-directional pattern in horizontal plane

March 2004

Communications Research LaboratorySlide16Submission

doc.:IEEE802.15-04-0114-00-003a

• Proposed antenna has dual frequency with wide bandwidth.

Planar monopole antenna with dual frequency

upper : rectangle element

lower : planar rectangular monopole antenna

ConclusionConclusion

• The return loss level at the eliminated frequency between

both resonances is almost 0 dB.

•Radiation pattern is omni-directional in horizontal plane.