In this paper the use of a crossed-dipole array is proposed in joint space-time channel estimation for asynchronous multipath DS-CDMA systems. The polarisation diversity offered by such an array, unlike linearly polarised arrays, is shown to provide a better and more consistent estimation which is less sensitive to the signal polarisation. By utilising the polarisation information inherent in t...

We introduce an alternative method for the retrieval of polarisation in the ultraviolet by the satellite spectrometer SCIAMACHY. Unlike the operational polarisation retrieval algorithm, this method does not use the Polarisation Measurement Devices (PMDs) onboard SCIAMACHY, but only requires the reflectance signal. This makes the algorithm more robust and less sensitive to calibration errors cau...

Many animals have sensitivity to the e-vector of linearly polarised light, which may assist in visually mediated behaviours such as navigation, signalling and foraging. However, it is still controversial as to whether birds possess polarisation sensitivity. Several studies have found that altering the polarisation patterns of the broad visual field surrounding birds alters their intended migrat...

Diffuse neutron scattering measurements incorporating polarisation analysis have been made on a single domain single crystal of MnCu 90 at. % Mn at 5 K. The atoms are strongly clustered and the long range part of the magnetic defect is transverse to the antiferromagnetic direction. The face centred tetragonal form of manganese which can be stabilised at room temperature by the addition of small...

In neutron scattering by C2CI6 the incoherent contribution to the quasielastic linewidth gives information on the reorientational motion of the molecules by scattering on individual atoms. The coherent scattering contains in contrast also interference effects. With polarisation analysis it is possible to distinguish between coherent and spin incoherent scattering. If it is possible to modulate ...

background: several landmine detection methods, based on nuclear techniques, have been suggested during the recent years. neutron energy moderation, neutron-induced gamma emission, neutron and gamma attenuation, and fast neutron backscattering are nuclear-based methods used for landmine detection. the aim of this study is to use backscattered neutron for landmine detection. materials and method...

Polarisation has proven to be an effective method in the analysis of light reflection in computer vision. It plays an important role in separating reflectance components using cross polarisation settings. Some polarisation based methods have also been presented in the literature for surface orientation estimation, where the incident light is unpolarised. This thesis aims at exploiting the polar...

A telescope of three silicon detectors has been installed close to the internal target position of the ANKE spectrometer, which is situated inside the ultra-high vacuum of the COSY-Jülich light-ion storage ring. The detection and identification of slow protons and deuterons emerging from a deuterium cluster-jet target thus becomes feasible. A good measurement of the energy and angle of such a s...

In a series of paper, it has been shown that the distribution of polarisation position angles for visible light from quasars is not random in extremely large regions of the sky. As explained in a recent article, the measurement of vanishing circular polarisation for such quasars is an important problem for a mechanism involving the mixing with axionlike particles in external magnetic fields. In...

The small degree of circular polarisation observed in some synchrotron sources has a frequency dependence that is not consistent with simple predictions based on the intrinsic circular polarisation of synchrotron emission. The suggestion is explored that the circular polarisation arises as a propagation effect within the source. The physical basis of this alternative mechanism is the fact that ...