transfer matrix method (tmm) has been applied to analyze characteristics of semiconductor laser optical amplifiers. the input signal is sinusoidal modulating wave and we do not assume the modulating bias signal as well. we have shown that the distoration arises from gain modulation at low modulation frequencies, but in microwave modulation frequencies, the gain takes an average value and the re...

In this paper, we applied Continuous Phase Frequency Shift Keying (CPFSK) to Trellis Coded Quantization/Modulation (TCQ/TCM) and thus we called Trellis Coded Quantization/ Continuous Phase Modulation (TCQ/TCCPM) for this new system. In this new scheme we use continuous phase frequency shift keying signal set instead of phase shift keying signal set. As an example, an eight state TCQ/TCCPM syste...

orexin, mainly produced by orexin-expressing neurons in the lateral hypothalamus (lh), plays an important role in pain modulation. moreover, it is shown that the nucleus accumbens (nac) is one of the important areas involved in this modulation. orexin-1 (ox1) and orexin-2 (ox2) receptors are densely distributed in the nac. the study investigated the involvement of ox1 receptors in the nac on an...

This paper deals with mechanical fault diagnosis in three-phase induction machines from stator current measurements. According to machine models, mechanical faults lead to amplitude and/or phase modulations of the measured stator current with possibly time varying carrier frequency. The modulation diagnosis requires a univocal definition of the instantaneous phase and amplitude. This is perform...

Adaptive digital modulation in the optical domain is performed using an integrated optical modulator with a high symbol rate of 10 Gbaud. The optical digital-to-analogue conversion technique that employs an optical IQ modulator and a dual-polarization quadrature-phase-shift-keying (DP-QPSK) modulator is applicable to binary PSK, QPSK, and 16-ary quadrature amplitude modulation. Analogue modulat...

Various binary and non-binary modulation techniques, in conjunction with appropriate detection techniques, are compared in terms of their spectral efficiencies and signal-to-noise ratio requirements, assuming amplified spontaneous emission is the dominant noise source. These include (a) pulse-amplitude modulation with direct detection, (b) differential phase-shift keying with interferometric de...

Rapid voltage-controlled phase modulation of cw terahertz (THz) radiation is demonstrated. By transmitting an infrared beam through a lithium niobate phase modulator the phase of the THz radiation, which is generated by the photomixing of two infrared beams, can be directly modulated through a 2pi phase shift. The 100 kHz modulation rate that is demonstrated with this technique is approximately...

An approach to implementing optical single sideband (OSSB) polarization modulation, which is a combination of two orthogonally polarized OSSB modulations with complementary phase differences between the optical carrier and the sideband, is demonstrated based on two cascaded polarization modulators (PolMs). The two PolMs are driven by two RF signals that are 90° out of phase. By properly adjusti...

A novel ultracompact electro-optic phase modulator based on a single 9 μm-diameter III-V microdisk resonator heterogeneously integrated on and coupled to a nanophotonic waveguide is presented. Modulation is enabled by effective index modification through carrier injection. Proof-of-concept implementation involving binary phase shift keying modulation format is assembled. A power imbalance of ∼0...