Acta Metallurgica Sinica(English letters) ›› 2009, Vol. 16 ›› Issue (6): 43-48.doi: 10.1016/S1005-8885(08)60287-3

• Wireless • 上一篇    下一篇

EVM simulation and analysis in digital transmitter

谭晓衡,李腾蛟   

  1. College of Communication Engineering, Chongqing University, Chongqing 400044, China
  • 收稿日期:2009-03-12 修回日期:1900-01-01 出版日期:2009-12-30
  • 通讯作者: 谭晓衡

EVM simulation and analysis in digital transmitter

TAN Xiao-heng , LI Teng-jiao   

  1. College of Communication Engineering, Chongqing University, Chongqing 400044, China
  • Received:2009-03-12 Revised:1900-01-01 Online:2009-12-30
  • Contact: TAN Xiao-heng

摘要:

The error vector magnitude (EVM) is extensively applied as a metric for digital transmitter signal quality compliance in modern communication systems. This article is focused on the effects of local oscillator (LO) phase noise and nonlinear distortion of power amplifier on EVM. This article contributes to below aspects. First, the relationships between EVM and two effects, LO phase noise and nonlinear distortion of power amplifier, are derived and expressed. Second, to simplify the expression, the third-order intermodulation distortion (IMD3) is used to calculate the EVM. Then, an expression for the EVM is derived based on the digital transmitter model that considers local oscillator phase noise and nonlinear distortion of power amplifier. Finally, the math formula of bit error rate (BER) versus EVM is given which can be easier and more useful to predict BER, according to analysis of the relationship between EVM and signal to noise rate (SNR), inspired by the works of Rishad, Md. Shahriar and AHM, 2006. Simulations are carried out to display the performance of EVM based on these relationships.

关键词:

;power;amplifiers,;EVM,;phase;noise,;nonlinear;distortion,;IMD3

Abstract:

The error vector magnitude (EVM) is extensively applied as a metric for digital transmitter signal quality compliance in modern communication systems. This article is focused on the effects of local oscillator (LO) phase noise and nonlinear distortion of power amplifier on EVM. This article contributes to below aspects. First, the relationships between EVM and two effects, LO phase noise and nonlinear distortion of power amplifier, are derived and expressed. Second, to simplify the expression, the third-order intermodulation distortion (IMD3) is used to calculate the EVM. Then, an expression for the EVM is derived based on the digital transmitter model that considers local oscillator phase noise and nonlinear distortion of power amplifier. Finally, the math formula of bit error rate (BER) versus EVM is given which can be easier and more useful to predict BER, according to analysis of the relationship between EVM and signal to noise rate (SNR), inspired by the works of Rishad, Md. Shahriar and AHM, 2006. Simulations are carried out to display the performance of EVM based on these relationships.

Key words:

power amplifiers;EVM;phase noise;nonlinear distortion;IMD3