Millimeter-wave signal generation device based on difference frequency generation in a LiTaO3 rectangular waveguide
We have proposed a new DFG-based signal generation device in a LiTaO3 rectangular waveguide. 15 GHz signal was successfully generated from the fabricated device. In this paper, its application for higher-frequency signal generation is discussed.
Travelling-wave electro-optic modulators with arbitrary frequency response utilising non-periodic polarisation reversal
A new design to realise travelling-wave electro-optic modulators, which utilise a non-periodically polarisation-reversed structure to produce an arbitrary frequency response, is proposed. A flat and broadband electro-optic modulator compensated for both velocity mismatch and degradation by microwave loss is presented.
A preliminary account of a new tyrannosauroid theropod from the Wessex Formation (Early Cretaceous) of southern England
Abstract A new genus and species of coelurosaurian theropod dinosaur from the Wessex Formation (Early Cretaceous, Barremian) of the Isle of Wight, England, is described and named. Distinctive characters of the premaxilla, its dentition, maxilla and nasals allow it to be diagnosed. The teeth in the premaxilla are D-shaped in cross-section and the nasals are fused. The hands are elongate and slender and the hindlimbs are gracile. Lack of element fusion elsewhere in the skeleton suggests that it is a subadult. Numerous character states are shared with tyrannosaurids but the new taxon appears to be excluded from the group that comprises aublysodontine and tyrannosaurine tyrannosaurids. We conclude that the taxon is a basal tyrannosauroid and as such it is one of the earliest and (with the exception of some teeth and an isolated ilium from Portugal) the first from Europe. Implications for tyrannosauroid biogeography and evolution are discussed. The animal was part of an unusual taphonomic assemblage in which some elements were partially articulated while others were scattered or broken.