Past studies have shown evidence of important speakerspecific content in the higher frequencies of the spectrum, which are filtered out by narrowband channels. Besides, wideband transmissions, which are gaining ground over narrowband communications, offer an extended range of frequencies which account not only for better speech quality and intelligibility, but also for an improved speaker recog...

This paper presents a bi-modal coding paradigm to compress narrowband audio signals at 8 kbit/s. In the general mode, the Enhanced Narrowband Audio Coder (ENPAC) exploits the characteristics of the human hearing system to adaptively code the perceptually important spectral components of the input audio. The other mode is employed to handle audio inputs with a strong harmonic structure. In that ...

This paper presents the analysis of Ricean K-factor for wideband high-speed railway channels at 2.35 GHz, based on radio channel measurements under viaduct and U-shape cutting scenarios. We characterize the K-factor from the perspective of narrowband, wideband and delay, according to the measured channel responses. The time-frequency varying narrowband K-factors in two scenarios are analyzed an...

When wideband and narrowband interferences in a GPS system are stationary, a large number of data samples may be obtained to get a good estimate of the interference. However, the jamming environment may be one in which the narrowband jammers have the ability to change frequencies dynamically or the rapid dynamics of the aircraft during maneuvering causes arrival angles of wideband jammers to ch...

Topical pimecrolimus and narrowband ultraviolet B (UVB) are both known to be effective in treating atopic dermatitis. We compared the clinical efficacy of monotherapy with either twice daily topical 1% pimecrolimus cream or twice weekly narrowband UVB, and combination therapy in 26 children and adolescents with moderate to severe atopic dermatitis in a half-side manner for 6 weeks. Twenty-four ...

Telephone speech is typically bandlimited to 4 kHz, resulting in a ‘muffled’ quality. Coding speech with bandwidth greater than 4 kHz reduces this distortion, but requires a higher bit rate to avoid other types of distortion. An alternative to coding wider bandwidth speech is to exploit correlation between the 0-4 kHz and 4-8 kHz speech bands to resynthesize wideband speech from narrowband spee...

In this paper, we introduce narrowband uplink transmission scheme to adapt orthogonal frequency division multiple access scheme to satellite environments. Maximizing the commonalities with the terrestrial system is one the most important factors for cost-effective service delivery, which will finally bring successful deployment of the system. For this purpose, we adopt an orthogonal frequency d...

Techniques for artificial bandwith extension (ABWE) [1] aim to extend the limited audio bandwidth of current narrowband telephone systems (0.3 – 3.4 kHz) towards the wideband frequency range (0.05 – 7 kHz). In several studies, a consistent quality advantage of the enhanced signals over narrowband speech is reported, e.g., [2]. In this contribution we evaluate an ABWE algorithm under realistic c...

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...