A novel current-mode active-only single-input and four-output (SIFO) universal filter using four plus-type second-generation current-controlled conveyors (CCCIIs), one operational transconductance amplifier (OTA) and two operational amplifiers (OAs) is presented. The circuit is fully programmable and implements simultaneously lowpass (LP), bandpass (BP), highpass (HP) and Notch (BS) functions w...

Effective demodulation of amplitude and phase is a requirement in wide array applications. Recent efforts have increased the performance, particular, Lyapunov demodulator allows bandwidths up to carrier frequency signal. However, being inherently restricted first-order filtering input signal, it highly sensitive components outside its passband region. This makes unsuitable for certain applicati...

As discussed in Chapter 1, in an outphasing power amplifier system, the AM of a bandpass waveform is transformed into PM of two signals prior to power amplification, and finally recovered by recombining the two amplified signals. As shown in Figure 1.16, with this approach, two highly efficient nonlinear power amplifiers can be used without distorting the original signal. This is the main advan...

Currently, a number of wireless access systems have been available to users. Especially, several new systems can be used on not only 800-6000MHz band that is suitable for cellular communications and broadband wireless access systems but also the lower frequency band such as VHF and UHF bands. This means that most frequency bands adequate for mobile communication systems are fully occupied after...

Abstract Group velocity superluminal phenomenon, also known as negative group delay or refers to a of envelope signal at the output end medium before input, in time axis, is leave appears entering medium, but this does not violate causality. Based on waveguide theory delay, paper uses transfer function, amplitude response and phase shift electronic circuit control velocity, introduces three fir...

We report on the formation of various intensity pattern types in detuned Fourier domain mode-locked (FDML) lasers and identify corresponding operating conditions. Such patterns are a result complex laser dynamics serve as an ideal tool for study underlying physical processes well model verification. By numerical simulation we deduce that is related to spectral position instantaneous lineshape w...

Abstract A 1.7 ?m gain-switched thulium-doped all-fiber laser with a master oscillator power amplifier (MOPA) configuration, utilizing bandpass fiber filter and 1550 nm erbium/ytterbium-codoped MOPA, is demonstrated. The influences of pump pulse parameters (repetition rate duration) cavity structures (ring linear) on the performances were experimentally investigated. To best our knowledge, quen...