Overview on the Phase Conjugation Techniques of the Retrodirective Array

Abstract

This paper presents an overview on the phase conjugation techniques of the retrodirective antenna array. The concepts, advantages, and disadvantages of phase conjugation techniques are introduced. The self-phasing characteristic and technical difficulties of the array are presented as well as their structures and applications. Further researches in this area are presented finally.

Directional-modulation-enabled physical-layer wireless security

“…In order to achieve retrodirective retransmit functionality, a phase conjugator (PC) is required [35]. Next we discuss how a classical RDA is altered to form a synthesis-free DM transmitter.…”

Secure Wireless Key Establishment Using Retrodirective Array

“…An RDA has the capability to re-transmit a signal back along the spatial direction(s), along which the array was illuminated by the incoming signals without the need for a-priori knowledge of their points of origin [19]. The core element of an RDA that enables the tracking functionality is the phase conjugator unit [22]. Among many forms of phase conjugator units, active analogue types are attractive due to their low power consumption, real-time response, and frequency reconfiguration flexibility [23], [24].…”

Analog/Digital Hybrid Delay-Locked-Loop for K/Ka Band Satellite Retrodirective Arrays

“…Passive solutions normally refer to 'Van Atta' type structures [10], which retrodirect wavefronts using symmetrical delay lines positioned between array radiating elements. While active solutions usually involve phase conjugating circuits [11]. In this category 'Pon'-type phase conjugator (PC) structures [12] have been extensively investigated.…”