Automatic Modulation Classification is a procedure performed at the receiver based on the received signal before demodulation when the modulation format is not known to the receiver. : Automatic Modulation Classification is also believed to play an important role in the implementation of Software Defined Radio (SDR) of the 4thGeneration (4G) communication system. The ability to automatically se...

Wavelength reuse in a bidirectional radio-over-fiber link is proposed and demonstrated based on the cross-gain modulation (XGM) and the cross-polarization modulation in a semiconductor optical amplifier (SOA). With a polarization beam splitter placed at the remote antenna unit, the polarization-modulated signal generated at the SOA is converted into noninverted and inverted intensity-modulated ...

A generalized rate equation model is used to simulate the interrelated amplitude and frequency modulation properties of Electrooptically Modulated Vertical Compound Cavity Surface Emitting Semiconductor Lasers in both large and small signal modulation regimes. It is shown that the photon lifetime in the modulator subcavity provides the ultimate limit for the 3 dB modulation cutoff frequency. It...

—The method of block orthogonal amplitude modulation (QAM) is presented and the demodulation recognition method is studied in this paper. Based on ordinary orthogonal modulation, the basic feature vector is extracted from the received signal cluster sample to estimate the signal parameters of data block for achievement of data block demodulation by using matrix transformation which can reach t...

A continuous phase modulation (CPM) implementation alternative of a recently standardized class of Feher-patented quadrature phase-shift keying (FQPSK-B) modulation is proposed. It is based on the fact that FQPSK-B signal has quasi-constant amplitude and continuous phase characteristics, allowing CPM interpretation. Based on this, we derive the modulation index, premodulation filter and alterna...

This paper proposes an efficient modulation in high-speed inter-chip data communication with inductive-coupling wireless connection for 3D-stacked system in package (SiP). In this modulation, signal is generated only in one polarity of the digital signal transmission. Compared with BPM and NRZ modulation, it has a 50% power reduction and better crosstalk immunity.

Modulation identification is one of the most challenging steps for blind receivers. If frequency offset is present in the system, this process becomes even more difficult. The proposed method is based on the estimation of the modulation types for quadrature amplitude modulation (QAM) even before correcting the frequency offset. The modulation order is estimated using the probability density inf...

Digital modulation signal instantaneous characteristics are susceptible to noise interference, and instantaneous frequency extraction is easy to be folded and distorted. In this paper, a novel digital signal modulation mode identification algorithm under low SNR is proposed. In the algorithm, empirical mode decomposition (EMD) has been employed to extract signal instantaneous characteristics fi...

The paper summarizes the FMT modulation prototype filter design and its efficient implementation on DSP. The optimum design of algorithms for digital signal processors with VLIW architecture is described. Using this new approach it was, for example, possible to optimize compilation from the C language into the assembler of TMS320C6414 digital signal processor for implementation of FMT modulatio...