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1

Integrated filtering antenna with high selectivity band rejection for UWB applications

Alhegazi A., Zakaria Z., Shairi N., Salleh A., Ahmed S.

Przegląd Elektrotechniczny

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2016

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R. 92, nr 9

224--228

EN

In this paper, a new design composed of an UWB monopole antenna integrated with bandstop filter (BSF) has been proposed. The bandstop filter is constructed by using a defected microstrip structure (DMS). The proposed design covers frequency bandwidth from 3 GHz to 14 GHz (129.5%), with single band rejection from 5.1 GHz to 5.8 GHz (12.8%). The new integration of filter and antenna shows a high level of rejection, wide impedance bandwidth, realized peak gain of 5.23 dB and stable omnidirectional azimuth pattern. Therefore, the proposed design is suitable to be used in reducing the possible interference problem for the UWB applications.

PL

W artykule opisano projekt anteny UWB ze zintegrowanym filtrem. Filtr został wykonany z wykorzystaniem struktury mikropaska . Antena umożliwia wykrywanie sygnałów w paśmie 3 – 14 GHz z możliwością usuwania pasma 5.1 – 5.8 GHz. Umożliwia to rozwiazywanie problemu interferencji fal.

2

Polarity-reversed ultra-wideband monocycle pulse generation with dual-channel multicasting in a photonic crystal fiber

Gong J, Hui Z

Optica Applicata

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2015

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Vol. 45, nr 1

25--39

EN

This paper proposes and demonstrates a novel scheme of a two-channel-output ultra-wideband monocycle pulse generator consisting of a 100 m dispersion-flattened highly nonlinear photonic crystal fiber and two optical bandpass filters. Based on the cross-phase modulation effect in a dispersion-flattened highly nonlinear photonic crystal fiber, two polarity-reversed ultra-wideband monocycle pulses simultaneously output from two different channels are successfully achieved by appropriately locating the probe wavelength at the left linear slope and the right linear slope of the two optical bandpass filters transmission spectra, respectively. The full width at half-maximum and a fractional bandwidth of 24 ps and 260% for a positive pulse, 24 ps and 251% for a negative pulse are obtained. Moreover, the influences of input signal powers, the polarization misalignment between the data light and the continuous wave probe light, and probe wavelength variation on the double output ultra-wideband signals quality are also investigated. The results show that the system has some tolerance to both the input signal power fluctuation and the slight polarization mismatch and even can efficiently operate with a widely tunable wavelength range. This makes it very attractive for engineering applications in future multiuser ultra-wideband-over-fiber communication systems.

3

Converged ultra-wideband and multi-level wired signal downstream transport over single wavelength in wavelength-division multiplexing passive optical network

Ma H, Wang F., Wang W., Zhang X, Yu Q.

Optica Applicata

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2015

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Vol. 45, nr 4

433--445

EN

Simultaneous providing services of ultra-wideband and wired signal over single wavelength can greatly decrease the complexity and reduce the costs of a wavelength-division multiplexing passive optical network. However, ultra-wideband signal occupies the spectrum range from 3.1 to 10.6 GHz, and a narrow idle frequency band (from 0 to 3.1 GHz) could be employed to transport wired signal with a limited rate. In this paper, we proposed a scheme to simultaneously provide ultra-wideband and wired services, in which the information rate of the wired signal is enhanced by employing a multi-level amplitude switch keying signal in the idle frequency band formed by ultra-wideband signal. In comparison with other advanced modulation formats used for wavelength-division multiplexing passive optical networks such as orthogonal frequency division multiplexing, multi-level amplitude switch keying signal can be easily received by using intensity modulation direct detection, which will greatly reduce the cost of end-users. Especially, if a multi-band ultra-wideband signal is substituted for the direct-sequence ultra-wideband signal, the available spectrum range to transport wired signal will be easily extended to 5 GHz as multi-band ultra-wideband signal has a narrower spectrum width and flexible center frequency, so 4-amplitude switch keying signal with a rate of 5 Gbaud will achieve an information rate of 10 Gbit/s.

4

Optical generation of ultra-wideband signals with a reconfigurable spectral notch-band

Xiang P., Chen Y., Chen D., Zhao J.

Optica Applicata

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2014

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Vol. 44, nr 3

411--419

EN

A novel method for optical generation of ultra-wideband signals with a reconfigurable spectral notch-band is proposed. In the proposed system, ultra-wideband signals are generated in the optical domain and an optical tunable delay line is deployed to introduce a notch-band to the spectral profile of the generated ultra-wideband signals, which can effectively avoid the signal interference between ultra-wideband signals and pre-planned narrowband wireless signals used in wireless local area networks (WLAN). A theoretical model describing the proposed system is derived; the optical generation and fiber transmission of ultra-wideband signals with a reconfigurable notch-band are demonstrated via computer simulations.

5

Poprawa warunków międzysystemowej kompatybilności elektromagnetycznej radia impulsowego

Sadowski J., Katulski R.J.

Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne

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2008

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T. 15

31-36

PL

Referat zawiera opis jednej z możliwych technik modyfikacji widma sygnału ultraszerokopasmowego radia impulsowego na przykładzie standardu IEEE 802.15.4a, opartą o zmianę struktury sekwencji generowanych impulsów o bardzo krótkim czasie trwania. Technika ta może zmniejszyć ryzyko wzajemnych zakłóceń pomiędzy nowymi urządzeniami ultraszerokopasmowymi a istniejącymi urządzeniami radiokomunikacji wąskopasmowej.

EN

This article presents one of possible techniques of IEEE 802.15.4a ultra-wideband signal spectrum control, based on changes in sequences of transmitted pulses with very short duration time. This technique can reduce probability of mutual interferences between new ultra-wideband and existing narrowband devices, which may be helpful in further studies on allowing UWB transmission in wider range of spectrum in the European Union.