Sistemas retrodirectivos para la comunicación inalámbrica full-dúplex con alta eficiencia espectral

Abstract

In this paper, highly efficient and linear wireless transmitting architectures are extended to retrodirective arrays (RDAs) for assuring full-duplex communications using spectrally efficient digital modulation formats. Dynamic biasing a single FET resistive mixer topology, or pumping two of them with properly outphased local oscillator excitations, the amplitude and phase components of the signal to be retransmitted may be recombined over an arriving interrogation with a different modulation format. Two 4x1 RDAs have been implemented, designed over dual-gate FET (DGFET) or Enhancement-mode PHEMT (EPHEMT) devices. Thanks to the incorporation of digital pre-distortion, the linear retro-transmission of a CDMA 2000 wireless signal is demonstrated.