Journal of Navigation and Port Research (한국항해항만학회지)

Korean Institute of Navigation and Port Research (한국항해항만학회)
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Design of IMT-2000 Feedforward Digital Adaptive Linear Power Amplifier

IMT-2000 전방궤환 디지털 적응 선형전력증폭기 설계

  • Kim, Kab-Ki (Mokpo National Maritime University, Faculty of Marine Electronic. and Communication Eng.) ;
  • Park, Gyei-Kark (Mokpo National Maritime University Faculty of Maritime Transportation System)
  • 김갑기 (목포해양대학교 해양전자통신공학부) ;
  • 박계각 (목포해양대학교 해상운송시스템학부)
  • Published : 2002.08.01
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Abstract

Currently digital communication system adapt various digital modulation schemes. All these communication systems are required to cause the minimum interference to adjacent channels, they must therefore employ the linear power amplifiers. In respect to linear power amplifiers, there are many linearization techniques. Feedforward power amplifier represent very wide bandwidth and high linearization capability. In the feedforward systems overall efficiency is reduced due to the loss of delay line. In this paper, delay filter instead of transmission delay line adapted to get more high efficiency. Experimental results showed that ACLR has improved 17.04dB which is added 2.54dB by using the delay filter.

현재의 디지털 통신시스템은 매우 다양한 디지털 변조방식을 채택하고 있다. 이러한 통신시스템에서는 인접채널에 대한 간섭을 최대한 줄이기 위해서 필연적으로 선형 전력증폭기를 요한다. 선형 전력증폭기는 매우 다양한데 그 중에서 전방궤환 전력증폭기는 구조상 광대역이면서 선형화 정도가 매우 우수하다. 전방궤환 전력중폭기에 사용되는 지연선로의 손실로 인하여 전체효율이 감소한다. 본 논문에서는 이러한 지연선로를 손실이 매우 작은 지연필터를 사용함으로써 효율과 선형성을 동시에 개선하였다. 측정된 결과 ACLR이 약 17.43dB 개선되었으며 이것은 지연필터를 사용함으로써 2.54dB 더 개선되었음을 나타낸다.

Keywords

References

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