Wireless data services have attracted increasing attention in the last few years. Boosted by the massive use of popular Internet-based services such as email, WWW etc., wireless wideband networks capable of supporting mobile multimedia services are being planned. An important requirement has been postulated for these wideband services they cannot be substantially more expensive than the voice s...

This paper presents an overview of different types of wideband direction of Arrival (DOA) estimation methods. Direction-finding algorithms have straight forward applications in Sonar and Radar, and are also useful in advanced satellite and cellular communication systems for adaptive beamforming of smart antennas. Coherent Signal Subspace Processing (CSSM), one of the earliest wideband DOA estim...

Wideband technologies in the unlicensed spectrum can satisfy the ever-increasing demands for wireless bandwidth created by emerging rich media applications. The key challenge for such systems, however, is to allow narrowband technologies that share these bands (say, 802.11 a/b/g/n, Zigbee) to achieve their normal performance, without compromising the throughput or range of the wideband network....

Wideband wireless access based on direct sequence code diviABSTRACT sion multiple access aimed at third-generation mobile communications systems is reviewed. W-CDMA is designed to flexibly offer wideband services which cannot be provided by present cellular systems, wi th various data rates as high as 2 Mb/s. The important concept of W-CDMA is the introduction of intercell asynchronous operation

Ultra-wideband (UWB) uses narrow band pulses of nano-seconds to provide high data rate communications .These narrow pulses spread the energy across a wide frequency band that is why it is called ultra-wideband. In this paper, we will discuss the UWB pulse modulation and multiple access modulation schemes using Pulse Position Modulation technique .The simulations are done in MATLAB software.

In this Letter, we demonstrate experimentally that a patchwork of four metal-insulator-metal patches leads to an unpolarized wideband omnidirectional infrared absorption. Our structure absorbs 70% of the incident light on a 2.5 μm bandwidth at 8.5 μm. It paves the way to the design of wideband efficient plasmonic absorbers in the infrared spectrum.

We consider the effect of mobility on a wideband direct sequence spread spectrum (DSSS) communication system, and study a scale-lag Rake receiver capable of leveraging the diversity that results from mobility. A wideband signal has a large bandwidthto-center frequency ratio, such that the typical narrowband Doppler spread assumptions do not apply to mobile channels. Instead, we assume a more ge...