High Isolation Compact Four-Port MIMO Antenna Loaded with CSRR for Multiband Applications

In this paper, a compact 4×4 multiple-input-multiple-output (MIMO) patch antenna has been presented for triple band operation. Out of the 4 antennas, two are tuned to cover DCS (Digital Cellular System) downlink and two are tuned to cover DCS uplink frequency separately along with two common operating frequency centered around 2.45 GHz and 875 MHz. Four complementary split-ring resonators (CSRRs) have been etched in the ground plane exactly below the four patch antennas for attaining compactness from 0.36λ02 to 0.13λ02. In addition to this, by optimizing CSRRs outer radius, one lower common band operation of around 875 MHz (0.031λ02) has been obtained. Two, square split-ring resonators (SRRs) are placed between patch antennas to increase isolation by almost 7 dB around DCS band. The proposed MIMO antenna has been fabricated on an FR4 substrate (60×60×0.8) mm3 with dielectric constant, εr=4.3 having an antenna area of 0.13λ02. The Proposed MIMO antenna has two common operating bands, 850–900 MHz, 2410–2466 MHz and one individual band from 1725–1770 MHz for one group of two antennas of dimensions 17×22 mm2 and another individual band from 1800–1845 MHz for another group of two antennas of dimensions 17×23 mm2, where reflection coefficient is less than −10 dB with a minimum isolation of 17 dB. Diversity performance of the proposed MIMO antenna has been verified experimentally on all three bands. However, there is a slight deviation in the DCS operating band due to two different groups of antennas.

‘Part of my Heritage’: Ladies’ Pipe Bands, Associational Culture and ‘Homeland’ Identities in the Scottish Diaspora

Throughout the imperial and non-imperial destinations to which Scots gravitated, they expressed their ethnic identities in various ways. To date, scholars have generally focused on either one particular aspect of Scottish expressions of identity, such as ethnic societies, or provided fleeting mentions of individual elements, such as pipe bands, without sustained analysis. Since most Scottish migrants did not join a Scottish association, it was their personal sense of Scottishness, which overshadowed their ethnic affiliations. This chapter will build on current scholarship by surveying Scottish ethnic identities through two new approaches: public group expressions of Scottishness as revealed by ladies’ pipe bands and their various connections to other forms of Scottish associational culture; and in the personal expressions of individual band members and their audience members across the diaspora. Further, this chapter sheds light on a glaring gap in scholarship regarding ethnic identities: the sense of identity held by multi-generational descent groups, as well as the extent to which these were articulated and reinvented.

ACOUSTIC BAND GAP FORMATION IN METAMATERIALS

We present several new classes of metamaterials and/or locally resonant sonic crystal that are comprised of complex resonators. The proposed systems consist of multiple resonating inclusion that correspond to different excitation frequencies. This causes the formation of multiple overlapped resonance band gaps. We demonstrate theoretically and experimentally that the individual band gaps achieved, span a far greater range (≈ 2kHz) than previously reported cases. The position and width of the band gap is independent of the crystal's lattice constant and forms in the low frequency regime significantly below the conventional Bragg band gap. The broad envelope of individual resonance band gaps is attractive for sound proofing applications and furthermore the devices can be tailored to attenuate lower or higher frequency ranges, i.e., from seismic to ultrasonic.

A ROBUST WATERMARKING SCHEME USING SELECTIVE CURVELET COEFFICIENTS

In this paper, a selective curvelet coefficient digital watermarking algorithm is proposed. Traditionally, curvelet watermarks are embedded into all sample frequency bands. However, the study of individual band behavior and the use of single band for watermarking have not been reported. The selective band will provide an addition security feature against any physical tampering. This paper aims to give an intensive study on the robustness of watermarking using selective curvelet coefficients from a single band and to find out the best band for embedding watermark. Wrapping of specially selected Fourier samples is employed to implement Fast Discrete Curvelet Transforms (FDCT) to transform the digital image to the curvelet domain.

Putting spanners in the works: the politics of the 99 Posse

This article examines the politics of the Neapolitan rap band 99 Posse. Growing up in a city characterised by high unemployment and crime, individual band members independently gravitated towards far left politics, and emerged in late 1991 as the house band of the ‘Officina99’, an autonomist squat in the east of the city which gave the group its name. This article examines their political commitment through their songs, covering subjects from youth unemployment to the exploitation of casual workers. Another theme is how, over a decade, their initial denunciation of ‘communism’ mutated into sympathy. It is argued that the reason for their huge success – apart from their rather controversial decision to sign up with a major multinational such as BMG – lies in their ability to make these themes relevant to disaffected young people.

Identification Atlases of Molecular Spectra

In astrophysics, as in all research fields in which molecular spectra play important roles, there has been a continuing need for compendia of information on individual band systems. Firstly there is a requirement by observers and experimenters for aids to definitive identification of observed spectral features. Secondly there are needs by observers, by those who make diagnostic interpretations of spectral profiles, and also by theorists, for definitive critical compilations of appropriate molecular data with reference to the relevant literature. The continued popularity of various editions to Pearse and Gaydon’s Identification of Molecular Spectra (1) and to Huber and Herzberg’s Constants of Diatomic Molecules (2) are clear evidence of this.