Tommaso A. Cappello, Prathamesh H. Pednekar, C. Florian, Z. Popovic, T. Barton
{"title":"Supply Modulation of a Broadband Load Modulated Balanced Amplifier","authors":"Tommaso A. Cappello, Prathamesh H. Pednekar, C. Florian, Z. Popovic, T. Barton","doi":"10.1109/MWSYM.2018.8439462","DOIUrl":null,"url":null,"abstract":"This work presents multi-level supply modulation of a load modulated balanced amplifier (LMBA). The RF-input LMBA employs dynamic active matching for efficient operation over an octave bandwidth. Supply modulation is a natural candidate to further enhance the back-off efficiency of this broadband amplifier due to its independence on RF carrier frequency. In the ET-LMBA prototype demonstrated here, an efficient hybrid multi-level converter (power DAC) produces supply levels from 10 to 30 V to modulate the drain of the balanced amplifier. Digital predistortion is used to linearize the ET-LMBA behavior at discrete steps and over frequency. This system is demonstrated at 2.1, 2.7 and 3.5 GHz with a 20-MHz, 10-dB PAPR signal showing composite efficiency improvement between 9 and 12 percentage points when supply modulation is employed, while maintaining linearity.","PeriodicalId":6675,"journal":{"name":"2018 IEEE/MTT-S International Microwave Symposium - IMS","volume":"1 1","pages":"304-307"},"PeriodicalIF":0.0000,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"15","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"2018 IEEE/MTT-S International Microwave Symposium - IMS","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/MWSYM.2018.8439462","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 15
Abstract
This work presents multi-level supply modulation of a load modulated balanced amplifier (LMBA). The RF-input LMBA employs dynamic active matching for efficient operation over an octave bandwidth. Supply modulation is a natural candidate to further enhance the back-off efficiency of this broadband amplifier due to its independence on RF carrier frequency. In the ET-LMBA prototype demonstrated here, an efficient hybrid multi-level converter (power DAC) produces supply levels from 10 to 30 V to modulate the drain of the balanced amplifier. Digital predistortion is used to linearize the ET-LMBA behavior at discrete steps and over frequency. This system is demonstrated at 2.1, 2.7 and 3.5 GHz with a 20-MHz, 10-dB PAPR signal showing composite efficiency improvement between 9 and 12 percentage points when supply modulation is employed, while maintaining linearity.