A multiband wavelength-division-demultiplexing (WDDM) structure, which incorporates cascaded substrate-mode holograms, is presented. The method can be used to design a WDDM device that consists of two or more layers of fundamental units (i.e., substrate-mode holograms). The fundamental unit is based on a diffracted grating and a substrate that include angular dispersion, wavelength bandwidth, a...

The thermal conductivity kappa of the layered s-wave superconductor NbSe2 was measured down to T(c)/100 throughout the vortex state. With increasing field, we identify two regimes: one with localized states at fields very near H(c1) and one with highly delocalized quasiparticle excitations at higher fields. The two associated length scales are naturally explained as multiband superconductivity,...

This paper presents a multiband CPW-fed slot antenna with L-slot bowtie tuning stub. The proposed antenna has been designed for PCS 1900, UMTS, WLAN 802.11 a/b/g and bluetooth applications, with a cost-effective FR4 substrate. The proposed antenna still radiate as omni-directional in azimuth plane and sufficient bandwidth for all above mentions. The proposed antenna works as dual-wideband, band...

This paper explores the issues in coexistence between Broadband Fixed Wireless Access, also know as WiMax or 802.16e, and Ultrawideband (UWB), specifically the multiband OFDM form of UWB as promoted by the WiMedia trade group. A multiband OFDM receiver can operate as a channelized radiometer to detect emissions from WiMax systems, either in the uplink or downlink channel. By using well known de...

Multiband spectrum access presents the next generation of cognitive radio networks (CRNs), where multiple bands are sensed and accessed to enhance the network’s throughput, improve spectrum’s maintenance, and reduce handoff frequency and data transmission interruptions due to the activities of the primary users. In this paper, we discuss the challenges and limitations of the major multiband spe...

A Planar antenna with Microstrip feed Sierpinski carpet fractal geometry for multiband applications is presented. The multiband behavior is analyzed through two fractal iterations. Self similarity property of fractal technology is applied in the antenna design to reduce the physical size, increase bandwidth and gain. The proposed antenna covers multi bands such as 1.8/5.59/5.78/6.4/6.63/7.84 GH...

We consider the problem of fusing an arbitrary number of multiband, i.e., panchromatic, multispectral, or hyperspectral, images belonging to the same scene. We use the well-known forward observation and linear mixture models with Gaussian perturbations to formulate the maximum-likelihood estimator of the endmember abundance matrix of the fused image. We calculate the Fisher information matrix f...