in this paper, a novel directional super wide band micro strip antenna based on a simple and new geometry has been proposed. the antenna exhibits the widest bandwidth ever reported to the authors’ knowledge from 50 ghz to 200 ghz. its radiation pattern is approximately steady in the frequency ranges of 50 ghz to 200 ghz. the antenna consists of a club-like radiating patch, a combination of thre...

Driven by the market success of high-quality Voice over IP technology, the introduction of wideband telephony with an acoustic bandwidth of at least 7 kHz is meanwhile also foreseen for “traditional” digital voice communication services such as ISDN, DECT, or UMTS. While wideband speech addresses the basic requirement of intelligibility (even for meaningless syllables), the perceived “naturalne...

In audio communication systems, the perceptual audio quality of the reproduced audio signals such as the naturalness of the sound is limited by the available audio bandwidth. In this paper, a wideband to super-wideband audio bandwidth extension method is proposed using an ensemble of recurrent neural networks. The feature space of wideband audio is firstly divided into different regions through...

In this paper, a simple DFT-domain pitch-scaling technique is used to extend the audio bandwidth of wideband speech (50Hz – 7 kHz) to the super-wideband range (50Hz – 12 kHz). Therefore, the higher frequencies of the wideband signal (6 – 7 kHz) are pitch-scaled with a scaling factor of four and the resulting, scaled signal is inserted into the 8 – 12 kHz band. A subjective listening test has be...

Super wideband (SWB) communication calls more and more attention as can be seen by the standardization activities of SWB extensions for well-established wideband codecs, e.g. G.722 or G.711.1. This paper presents a technical solution for extending the G.722 codec and compares the new technology to other standardized SWB codecs. Hereby, a closer look is given on the concept of extending technolo...

In this paper, the performance of extended super orthogonal space time trellis coded orthogonal frequency division multiplexing system is investigated in frequency selective wideband wireless channels. New 16, 32 and 64 states full rate extended super orthogonal space time trellis codes for quadrature phase shift keying is proposed using the generator matrix notation and their frame error rate ...

The intrusive speech quality model standardized by the ITU–T shows some limits in its quality predictions, especially in a wideband transmission context. They are mainly caused by strong differences in perceived quality when speech is transmitted over different telephone networks. Instrumental methods should provide reliable estimations of the integral speech quality over the entire perceptual ...

The paper proposes a high gain, metamaterial based super wideband (SWB) antenna. SWB antenna has two inverted U slots which are responsible for notches at 3.5 GHz and 5.5 frequencies. A flower-shaped slot is etched from the radiator to obtain characteristics. dimensions of 30×35 ×1.5 mm3 with FR4 substrate. frequency bandwidth 3.1 - 15 S11 < -10dB. unit cell designed simulated permittivity perm...

It is well known that the speaker discriminative information is not equally distributed over the spectral domain. However, it is still not clear whether that distribution is altered when the speech is transmitted through telecommunication channels, which introduce different kinds of degradations. In this paper we address the analysis of different frequency sub-bands when the speech is distorted...