On the Design of Modular Reflecting EM Skins for Enhanced Urban Wireless Coverage

Generalized Analysis and Unified Design of EM Skins

“…k 0 ω √ ε 0 µ 0 being the free-space wavenumber. Therefore, field distribution F o ref (r) (o ∈ {e, h}) may be computed by substituting (1)-( 2) in ( 5) and ( 6), and numerically integrating the arising {A o (r); o ∈ {e, h}} expressions to be then used in (7). However, such an approach is here avoided since it is numerically cumbersome and it is difficult to derive simple guidelines for the EMS synthesis.…”

“…Successively, subject to the condition r ≥ 10 λ (13) and using ( 12) in (7), it can be proved (see "Appendix A.1") that…”

“…On the other hand, it must be noted that (20) does not hold true in the reactive near field region [15]. While this latter scenario does not generally arise in wireless communications, the prediction of the corresponding field distribution, F e ref (r), can be numerically performed by using (7) along with the discretized versions of ( 5) and ( 6), but without benefiting of simple algebraic closed-form expressions as in the other regimes (20).…”

“…It is worth pointing out that the use of EMSs (i.e., both static and reconfigurable non-amplifying structures) has been proposed to improve the wireless coverage and the quality-of-service (QoS), while minimizing the energy requirements and the needs, in terms of network architecture and protocols, for their integration within the wireless infrastructure [4]- [7]. On the other hand, passive reflecting structures can only redirect the wireless energy they collect [4] [5], thus EMSs with electrically-large apertures are necessary in many applicative scenarios [10] [12]- [14] to gather/deliver a sufficient amount of power.…”

Multi-Scale Single-Bit RP-EMS Synthesis for Advanced Propagation Manipulation Through System-by-Design

“…Several research studies on the foundation, the modeling, the simulation, the design, and the test of EMSs are currently under development with a strong interdisciplinary effort combining chemistry, physics, metamaterial science, electromagnetic (EM) engineering, telecommunications, and signal processing expertises [1], [2], [3], [7], [8]. As a matter of fact, starting from their early conceptualization as thin metasurfaces are able to manipulate the wave propagation beyond Snell's laws [11], EMSs are considered as one of the key enabling factors of the revolutionary smart EM environment (SEME) paradigm in wireless communications [4], [5], [6], [12], [13]. This is motivated by the possibility that they enable to control the EM reflected power in user-defined directions/regions, hence potentially improving the coverage/quality of the resulting wireless network (see Fig.…”