Quality and intelligibility of narrowband telephone speech can be improved by artificial bandwidth expansion (ABE), which expands the speech bandwidth using only information available in the narrowband speech signal. This paper describes an ABE method that generates a high-band expansion using spectral folding and then modifies the magnitude spectrum of the expansion band with spline curves. Th...

For many applications, wideband signals are exploited for localization. A wideband signal is any signal whose energy is distributed over a bandwidth that is large in comparison to the signal’s center frequency. For example, ultrawideband (UWB) noise radars use wideband offering low probability of detection (LPD), while achieving good target detection and high resolution [1]. In the acoustic veh...

The global positioning system (GPS) provides accurate positioning and timing information useful in many applications. An adaptive lattice predictor for the anti-jamming purpose will be proposed. The adaptive filter is applied here to accurately predict the narrowband waveform based on an effective and computationally efficient stochastic-gradient algorithm. Simulation results show that our prop...

In this letter, a phase-sensitive, swept-source optical coherence tomography (SS-OCT) system is implemented for the optical measurement of nanostructures. A new approach is proposed to reduce the phase errors, resulting from trigger jitter of the swept source and the asynchronization between the A-scan trigger and OCT signal at the data acquisition end, with a narrowband fiber Bragg grating to ...

Multiphase flow imaging is a very challenging and critical topic in industrial process tomography. In this article, simulation and experimental results of reconstructing the permittivity profile of multiphase material from data collected in electrical capacitance tomography (ECT) are presented. A multiphase narrowband level set algorithm is developed to reconstruct the interfaces between three-...

Compressed sensing (CS) schemes are proposed for monostatic as well as synthetic aperture radar (SAR) imaging with chirped signals and Ultra-Narrowband (UNB) continuous waveforms. In particular, a simple, perturbation method is developed to reduce the gridding error for off-grid targets. A coherence bound is obtained for the resulting measurement matrix. A greedy pursuit algorithm, Support-Cons...

Absmucr-Direct sequence code division multiple access commun-kations is a promising approach to cellular mobile communications , whkh operates in an environment characterized by mul-tipath Rician fading. In this paper, the CDMA network is assumed to share common spectrum with a narrowband microwave user. Because of the presence of the narrowband waveform, an interference suppression filter at e...

Wireless telephone speech is usually limited to the 300 − 3400Hz band, which reduces its quality. There is thus a growing demand for wideband speech systems that transmit from 50Hz to 8000 Hz. This paper presents an algorithm to generate wideband speech from narrowband speech using as low as 500 bits/s of side information. The 50 − 300Hz band is predicted from the narrowband signal. A sourceexc...

This work is an exploration of the impact of interferers on an ultrawideband (UWB) transmitterreceiver link. Both narrowband and wideband (specifically, UWB) interference is considered. Two physical layer models are built and simulated. The performance metric is the link’s bit error rate (BER). For both the narrowband and UWB interferer models, the dependence of the BER on the power of the inte...

Fourier transform infrared (FT-IR) imaging spectrometers are almost universally used to record microspectroscopic imaging data in the mid-infrared (mid-IR) spectral region. While the commercial standard, interferometry necessitates collection of large spectral regions, requires a large data handling overhead for microscopic imaging and is slow. Here we demonstrate an approach for mid-IR spectro...