In this paper, we propose a fractional differential equation (FDE)-based approach for the estimation of instantaneous frequencies windowed signals as part signal reconstruction. This is based on modeling bandpass filter results around peaks equations and linking differ-integrator parameters, thereby determining long-range dependence estimated frequencies. We investigated performance proposed wi...

Improved radio frequency interference suppression method based on short time Fourier transform applied to synthetic aperture radar is proposed in this paper. The radio frequency interference, including narrow-band interference and wide-band interference, are analyzed in time frequency domain. The interference is identified at instantaneous frequency spectrum by a novel threshold criterion in ti...

Digital-to-analogue and analogue-to-digital in a digital array radar limits the transmission reception of instantaneous broadband signals (IBSs), which makes it technical bottleneck for to obtain an high-resolution range profile (HRRP). A frequency-agile orthogonal frequency division multiplexing (OFDM) waveform with high repetition pulse train is proposed, uses multiple narrowband OFDM realise...

The evolution along the tank of unidirectional nonlinear wave groups with narrow spectrum is studied both experimentally and numerically. Measurements of the instantaneous surface elevation within the tank are carried out using digital processing of video-recorded sequences of images of the contact line movement at the tank side wall. The accuracy of the video-derived results is verified by mea...

We report on the design and construction of a wideband spectrometer of 500 MHz instantaneous bandwidth that includes automatic radio frequency interference (RFI) detection. The implementation is based on hardware developed at the Center for Astronomical Signal Processing and Electronics Research (CASPER). The unique aspect of the spectrometer is that it accumulates both power and power-squared,...

The instantaneous optical frequency of an external-cavity quantum cascade laser (QCL) is characterized by comparison to a near-infrared frequency comb. Fluctuations in the instantaneous optical frequency are analyzed to determine the frequency-noise power spectral density for the external-cavity QCL both during fixed-wavelength and swept-wavelength operation. The noise performance of a near-inf...

We present the procedure for designing a high speed and low power all-optical analog to digital converter (AO-ADC), by integrating InGaAsP semiconductor optical amplifier (SOA) with InP based photonic crystal (PhC) drop filters. The self-phase modulation in the SOA can shift the frequency of the Gaussian input pulse. The two output PhC based drop filters are designed to appropriately code the f...