Design of UHF Class-E Inverters and Synchronous Rectifiers for Efficient Transmission Topologies

In this paper, the design of efficient transmitting architectures is addressed. Taking advantage of the modeling and characterization of novel active devices as GaN HEMT and E-pHEMT, several topologies have been approached. An outphasing transmitter at 770 MHz have been implemented from two class-E RFPA designed over package GaN HEMTs. In addition, for multiband applications, a dual band outphasing transmitter (able of operating either at 770 MHz or 960 MHz) has been also realized. A Chireix reactive combiner allows positioning the drain impedance loci to produce high efficiency and good dynamic range profiles, for both designs. Average drain efficiency figure over 61% has been measured for a 8.4 dB PAPR WCDMA signal, in the dual-band implementation. Besides, in the first approach, an efficient value of 57.5% was estimated when reproducing a LTE with a PAPR of 9.6 dB. On the other hand, wireless powering applications have been into account in the design of self-biased and self-synchronous class-E rectifier, based on an E-pHEMT. Two implementations at 900 MHz and 2.45 GHz, with efficient values of 76% and 64% at power levels of -4 dBm and -1 dBm, respectively, and peak figures of 88% and 77%, have been measured.