This article describes a method for estimating the subjective quality of wideband (7-kHz) speech solely from physical characteristics of terminals and networks. It enables efficient quality design and management of wideband speech communication services. The validity of this model was shown through experiments. Quality Assessment of Wideband Speech Communication Services Letters † NTT Service I...

As wireless communication applications require more and more bandwidth, the demand for wideband antennas increases as well. For instance, the ultra wideband radio (UWB) utilizes the frequency band of 3.1-10.6 GHz .In this paper we introduce a new multilayer microstrip antenna for ultra wideband applications. In order to achieve suitable bandwidth, the antenna size is fine for mobile application...

During the last two decades, Maximum Likelihood estimation (ML) has been used to determine Direction Of Arrival (DOA) and signals propagated by the sources, using narrowband array signals. The algorithm fails in the case of wideband signals. As an attempt by the present study to overcome the problem, the array outputs are transformed into narrowband frequency bins, using short time Fourier tran...

The application of MIMO communication systems in real environments will invariably require systems to operate over wideband channels. Although suitable techniques for processing wideband MIMO channels have been reported, their evaluation has mainly been based on simulation using modelled channels. In this paper we investigate some of the properties of wideband MIMO channels and compare the char...

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...

M OBILE communications services are penetrating our society at an explosive rate. The major services that the second-generation mobile systems provide are limited to basic services (e.g., voice and low-bit rate data). We have entered the 21st century, when demands for a variety of wideband services (e.g., high-speed Internet access and the video/high-quality images transmission) will continue t...

This paper is focused on a wireless energy harvesting system using a rectifying antenna (rectenna). The proposed device consists of a wideband cross-dipole antenna, a microwave low-pass filter and a doubling rectifying circuit using Shottcky diodes as rectifying elements. Previously, a few of wideband rectennas have been investigated at 1.7 to 2.5 GHz. The originality of this paper is on the ne...

For high data rate ultra wideband communication system, performance study of mutual interference such as suppression of interference signal by performing pulse shaping from UWB to other narrowband system using wavelet technique and reduction of interference from other narrowband system to UWB system in conjunction with Transmitted-Reference (TR-UWB) signaling scheme with adaptive receivers is a...

There have recently been research efforts that leverage compressive sampling to enable wideband spectrum sensing recovery at sub-Nyquist rates. These efforts consider homogenous wideband spectrum, where all bands are assumed to have similar PU traffic characteristics. In practice, however, wideband spectrum is not homogeneous, in that different bands could present different occupancy patterns. ...