Steering Focusing Waves in a Reverberation Chamber With Generalized Time Reversal

Abstract

Generalized time reversal was introduced in a previous paper from a theoretical point of view. In this paper experiments are conducted to demonstrate its application to a reverberation chamber, as a method for generating coherent wavefronts in a medium displaying random propagation. Wavefronts thus generated were sampled over a planar surface, confirming that they propagate as if in a free-space environment. The accuracy with which they match their free-space counterpart is not affected by changing their features, e.g., direction of arrival and focus. These results prove that a single excitation antenna can generate complex wavefronts when coupled to diffusive wave propagation.

Time reversal plasmas as a versatile space-time patterning deposition method

“…The interest of using a non-intrusive probe is the fact that moving the probe in the cavity does not change the behavior of the waves, so that when it is removed during the second step, sending a time-reserved impulse response by the antenna leads to a focusing at the desired location. This method of scanning the cavity in a non-intrusive manner has been proved to successfully work for microwave TR experiments using electro-optical probes (in a cavity of 6 × 3.5 × 2.5 m 3 ) [13].…”

Physical layer security performance analysis of the time reversal transmission system

“…The TR technique was originally designed for acoustics and ultrasound applications [6,7]. In the last decade, the applications of the TR technique in other fields have been researched, such as wireless communications [8,9], highresolution imaging [10], indoor positioning [11], spatial filed shaping [12] etc. Thanks to the spatial-temporal focusing effect of the TR technique, the signal energy at the target receiver can be improved.…”

“…As can be seen from (10) and (12), the expressions of the ISI powers of Bob and Eve are very complicated. To get ISI powers, the sum of multiple products of two random variables should be obtained and the squares of the sums are accumulated.…”