This paper establishes an upper bound on the capacity of line-of-sight multiantenna channels over all possible antenna arrangements and shows that uniform linear arrays (ULAs) with SNR-dependent rotation transmitter and/or receiver can closely approach such capacity-and in fact achieve it at low high SNR, asymptotically numbers antennas. Then, as alternative to mechanically rotating ULAs, we pr...

While most strong-gravitational-lensing systems may be roughly modelled by a single massive object between the source and observer, in details all structures near light path contribute to observed images. These additional contributions, known as line-of-sight effects, are non-negligible practice. This article proposes new theoretical framework model together with very promising applications at ...

The observability of radome aberration estimation with line-of-sight (LOS) angle-only measurement is studied in this paper. When missile seeker can only measure LOS angle of target, target state variables are required to be estimated with this measurement for accurate missile guidance. Since LOS angle measurement contains error, caused by radome attached at missile nose and called radome aberra...

The projected kinematical properties of unequal-mass merger remnants of disk galaxies are analysed and shown to agree well with observations of disky, fast rotating elliptical galaxies. This supports the major merger hypothesis of early-type galaxy formation. However, in contrast to previous claims, the merger remnants are very anisotropic with values of the anisotropy parameter that are simila...

In order to facilitate the deployment of wireless systems in medical environments, channel measurements at 2.4GHz band have been performed in a hospital bedroom. Based on measurements in different line-of-sight (LOS) and non-line-of-sight (NLOS) scenarios, we determine the large-scale path loss and different small-scale fading parameters. Applying the channel models in our MATLAB simulation env...

This paper presents an overview of the Line-of-Sight (LOS) guidance law, which is a widely used method for generating heading reference trajectories, for path-following applications of marine vehicles. Due to the fact that these reference trajectories depend also on the form of the path, five path evaluation criteria are discussed. The guidance problem is presented in a constructive manner. Fir...

We have selected quasars with X-ray colors suggestive of a low energy cutoff, from the ROSAT PSPC pointed archive. We examine the radio and optical properties of these 13 quasars. Five out of the seven quasars with good optical spectra show associated optical absorption lines, with two having high ∆v candidate systems. Two other cut-off quasars show reddening associated with the quasar. We conc...

Aims. Our purpose is to place firm observational constraints on the three most widely used theoretical models for the spatial configuration of the large-scale interstellar magnetic field in the Galactic disk, namely, the ring, the axisymmetric and the bisymmetric field models. Methods. We use the rotation measures (RMs) of low-latitude Galactic pulsars and combine them with their dispersion mea...

Measurements of the velocities of galaxies thought to be associated with the giant radio galaxy NGC 6251 confirm the presence of a poor cluster with a systemic redshift of z = 0.0244 ± 0.0004 and a line-of-sight velocity dispersion of σ z = 283 (+109, −52) km s −1. This suggests a cluster atmosphere temperature of T = 0.7 (+0.6, −0.2) keV, which is not enough to confine the radio jet by gas pre...

In this paper, two-dimensional percolation lattices are applied to describe wireless propagation environment, and stochastic rays are employed to model the trajectories of radio waves. We first derive the probability that a stochastic ray undergoes certain number of collisions at a specific spatial location. Three classes of stochastic rays with different constraint conditions are considered: s...