The rectenna device: From theory to practice (a review)

Abstract

The Rectenna (RECTifying antENNA), which was first demonstrated by William C. Brown in 1964 as a receiver for microwave power transmission, is now increasingly researched as a means of harvesting solar radiation. Tapping into the growing photovoltaic market, the attraction of the rectenna concept is the potential for devices that, in theory, are not limited in efficiency by the Shockley-Queisser limit. In this review, the history and operation of this 40-year old device concept is explored in the context of power transmission and the ever increasing interest in its potential applications at THz frequencies, through the infra-red and visible spectra. Recent modelling approaches that have predicted controversially high efficiency values at these frequencies are critically examined. It is proposed that to unlock any of the promised potential in the solar rectenna concept, there is a need for each constituent part to be improved beyond the current best performance, with the existing nanometer scale antennas, the rectification and the impedance matching solutions all falling short of the necessary efficiencies at THz frequencies. Advances in the fabrication, characterisation and understanding of the antenna and the rectifier are reviewed, and common solar rectenna design approaches are summarised. Finally, the socio-economic impact of success in this field is discussed and future work is proposed.

THz Rectennas and Their Design Rules

“…Furthermore, more than 35% efficiency has been reported in the experiment of Chiou and Chen [18] in 2010 at the 94-GHz band for a dual-band design thanks to using filtering and matching techniques for a pair of Schottky diodes at the circuit termination points. The interested reader may refer to [19] (Figure 7) for a detailed representation of the recent work in this field.…”

“…In a similar style to other models, A n,j and B n,j are the incoming and outgoing wave components in slice j; k n,j is the wave vector component and can be found by the knowledge of the potential v and particle energy E. Working out some math and replacing the j with the incident and outgoing indices in the following equation, the transmission probability T for slice j can be obtained from (19). Based on the knowledge of transmission probability, we can find the expected current value.…”

“…In order to quantitatively characterize the diodes as efficient rectifiers, Donchev et al [19] reinforced what has been set by [50,85,86] as the criteria that a diode should satisfy to be considered a rectifier. The rectifier figures of merit are asymmetry f asym (V), nonlinearity f NL (V) and responsivity f RES (V).…”

Numerical conversion efficiency of thermally isolated Seebeck nanoantennas

“…[1][2][3] Nanoantennas are metallic nanostructures that resonate to the free-propagating electromagnetic waves by inducing a high frequency AC resonant current along their volume. 4,5 This resonant current is subsequently exploited either to sense or recover the electromagnetic energy.…”

Systematic study of metal-insulator-metal diodes with a native oxide

“…[14][15][16][17] Asymmetry in the I-V curves of MIM devices should theoretically only exist when dissimilar metal electrodes are used. 5 This is due to the creation of different barrier heights at each metal-insulator junction as a result of the difference in metal workfunctions. Therefore, electron tunneling probability at any applied voltage is greater in the direction where the effective tunneling distance is shorter, giving rise to asymmetry in their electrical characteristics 5,13 (Figure 1).…”