This paper proposes new switch architectures for hierarchical optical path cross-connect (HOXC) systems. The architectures allow incremental expansion of system scale in terms of the number of input/output fiber ports, wavebands, and optical paths per waveband. These features assure the cost-effective introduction of HOXCs even at the outset when traffic volume is not so large. Furthermore the ...

This paper presents an efficient indirect fractional frequency synthesizer architecture based on the time delay digital tanlock loop. The indirect type frequency synthesis systems incorporate a low complexity high performance adaptation mechanism that enables them to remain in a locked state following the division process. The performance of the proposed fractional-N synthesizer under various i...

We derive an expression for the input complex impedance of a Sallen-Key second-order low-pass filter of twofold gain as a function of the natural frequency ωo and the quality factor . Q From this expression, it is shown that the filter behaves like a Frequency Dependent Negative Resistance (FDNR) element for low frequencies and as a single resistor at high frequencies. Furthermore, the minimum ...

TO THE EDITOR: There is much interest in the synchronization of neural discharge and its potential role in information coding within the nervous system. To assess oscillatory input to the muscle by means of corticospinal (EEG–EMG) coherence and intermuscular (EMG–EMG) coherence, it is common practice to rectify electromyographic (EMG) signals, although the rationale for rectification remains in...

Many hormones are released in pulsatile patterns. This pattern can be modified, for instance by changing pulse frequency, to encode relevant physiological information. Often other properties of the pulse pattern will also change with frequency. How do signaling pathways of cells targeted by these hormones respond to different input patterns? In this study, we examine how a given dose of hormone...

The purpose of this study was to quantify the influence of intrinsic properties, active dendritic conductances, and background excitation and inhibition on measures of discharge correlation in the time and frequency domains with known levels and patterns of common synaptic input. The study involved a computer simulation of a population of neurons with a range of input resistances (0.54-3.7 MOme...

In this paper, we have exploited the first-order sliding mode control method to track the ECG data of the human heart by three different nonlinear control laws. In order to lessen the intrinsic chattering of the classic sliding mode control system, smooth function approximations of the control input, by means of the hyperbolic tangent and the saturation function, were used. The fast Fourier tra...

The communication performance between reader and transponder in radio frequency identification (RFID) in the ultra high frequency (UHF) range strongly depends on the matching between transponder chip and transponder antenna. To assure power optimization in the forward link the input impedance of the antenna must be the complex conjugate of the chip’s input impedance. In this contribution a meas...

This paper introduces a variable step-size adaptive algorithm for blind source separation. From frequency characteristics of mixed input signals, we need to adjust the convergence speed regularly in each frequency bin. This algorithm varies a step-size according to the magnitude of input at each frequency bin. This guarantee of the regular convergence in each frequency bin would become more eff...