| Abstrakt: |
This study aimed to improve the power efficiency and complexity of an RF beamforming system transmitter operating indoors using a biasing control technique for each group. The group-by-group biasing technique applies both dynamic and group biasing techniques simultaneously. Using the dynamic biasing technique, an appropriate bias was applied to the output of the RF power amplifier for each channel to power the power amplifier in the low-power section. The efficiency was improved, and the system complexity that occurred when applying the dynamic biasing technique was reduced using the group biasing technique. The proposed technique was theoretically verified through mathematical modeling using the output characteristics of a single power amplifier. In addition, for actual measurement, a digital beamforming system with a 4×4 antenna structure was built, and a biasing control technique for each group was applied to the measurement. The measurement conditions were divided into three types according to the deviation of the output power of the group, and the measurement results showed total power efficiency improvements of 14.0 %p, 14.1 %p, and 10.5 %p, proving the validity of the technique. [ABSTRACT FROM AUTHOR] |
