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The behaviour of gas discharges can be modelled by equivalent circuits built on the basis of a theoretical description of the plasma. This paper introduces a method to develop a nonlinear equivalent circuit directly by means of the balance equations of the column plasma and by the help of the knowledge obtained from the design of the linear equivalent circuit. The linear network theory was used for the derivation. The circuit found in this way is similar to a derived linear equivalent circuit of the column plasma with two inertial factors (delayed effects) for a neon gas discharge described in previous papers.

ÜbersichtDie Matrixbeschreibung diskreter Multiraten-Systeme (MRS) läßt sich für die Berechnung hybrider MRS einsetzen, wenn zeitkontinuierliche Funktionen mit Hilfe der modifizierten z-Transformation diskretisiert werden. Auf der Grundlage dieser Überlegungen wird das Übertragungsverhalten determinierter und stochastischer Signale beim Übergang zwischen zeitdiskret und kontinuierlich arbeitenden Systemen untersucht. AbstractThe matrix description of discrete multirate-systems (MRS) can be applied for the computation of hybrid MRS if time continuous functions are made discrete with the aid of the modified z-transformation. Based on these considerations the transfer behaviour of deterministic and stochastic signals between discretely and continuously working systems is investigated.Für die Dokumentation Hybride Multiraten-Systeme / Matrixbeschreibung / determinierte und stochastische Signale / Übergang zwischen kontinuierlichen und zeitdiskreten Systemen Frequenz 52(1998) 1-2

Identifikation in Multirate-Systemen mittels mehrkanaliger schneller Transversalfilter 201 ConclusionA large-signal numerical model for a four level laser system has been described which is suitable for analysis of a Pr 3+ -doped fluoride fibre amplifier. This model takes into account the radial field distribution of the LP 01 mode in step-index single-mode fibre, realistic stimulated emission and signal excited state absorption cross-sections and the wavelength dependent fibre loss due to the signal ground state absorption. Small-signal and large-signal properties of a PDFFA have been investigated using this model. It has been found that the best performance is obtained when the cutoff wavelength of the LP^ mode is 750 nm, independent of fibre numerical aperture, input pump and signal power. Numerical aperture should be chosen as high as possible. Codirectional, counterdirectional and bidirectional pumping have been investigated and found to give equal amplification due to the lack of pump ES A. The effect of Pr 3+ confinement on smallsignal PDFFA operation has been studied. A 2 dB gain improvement has been predicted when the radius of the Pr 3+ -doped region is 65% of the fibre core.This work has been supported by the Alexander-von-Humboldt-Stiftung, References: [1] Zemon, S.; Pedersen, B; Umbert, G.; Miriscalco, W.J.; Hau, R T.; Folweiler, R.C.; Thomson, .; Andrews, L.J.: Exciled-state-ahsorpfion cross sections ud amplifier modeling in the 1300-nm region for Nd-doped glasses. IEEE Photon. TechuoL Lett. voL 4 (1992) pp. 244-247. [2] Ohishi, V.; Kanamori, T.; Nishi, T.; Takahashi, S.: A high gain, high onlpot saturation power Pr 3+ -doped fluoride fiber amphTier at IJ.ro. IEEE Photo» TechnoL Lett. ToL 3 (1991) pp. 715-717. [3] Ohishi, Y.; Kanamori, T.; Kitagawa, T.; Takahashi, S.; Saitzer, E.; SigeL G.H.: Pr s+ -doped fluoride fiber ampUOer operating at IJl urn. In Proc. of Conference on Optical Fiber Commmkation OFC *91, Washington DC 1991, paper PD2. [4] Miyajuna, Y.: Sngawa, T.; Fukusaku, Y.: 38J db amplification at 1 Jl urn and possibility of 0.98»m pumping in Pr 3 *-doped fluoride fibre. Electron. Lett. ToL 27 (1991) pp. 1706-1707. [5] Ohishi, Y.; Kanamori, T.; Temmyo, J.; Wada, M.; Yamada, M.; Shimizu, M; Yoduno, K.; Hanafnsa. H.; Horiguchi, M; Takahashi, S.: Laser diode pumped Pr>*-doped and Pr"-Yb"-codoped fluoride fibre amplifiers operating at 13nm. [6] Lobbett, R.; Wy.tt, R.; Eanfley, P.; Whitky. T.; Smyth, T. J.; Siebest«, D.; Carter, S.F.; Davey, S.T.; Millar, CA.; Brierlev, M.G.: System characterisation of high gain and high saturated output power Pr 3 *-doped fluororirconale fibre amplifier at U nm. Es wird ein schnelles Verfahren zur Identifikation in Multirate-Systemen vorgestellt Dieses basiert auf einer angepaßten Identifikationsanprdnung und einer mehrkanaligcn Version des FTF-Algorithmus und setzt eine geeignete Signalbeschreibung des Modellsystems voraus. Es werden Ergebnisse aus einer experimentellen Anwendung zur Echokompensation in Teilnehmeranschlußschaltungen dargestellt.Abstract: A fas...