The requirement for an object to be surrounded by empty space when imaged by coherent X-ray diffraction was once thought to be a fundamental limitation. A variant of coherent diffractive imaging ...

Abstract: It has been predicted theoretically that for some environments, the capacity of wireless multiple-input multiple-output systems can become very low even for uncorrelated signals; this effect ...

Abstract: Multiple antennas aided wireless communications under dense urban environments often suffer from keyhole effect, which leads to rank deficiency. Secrecy performance of artificial noise (AN) ...