An adaptive polarization-QAM modulation scheme for improving the power amplifier energy efficiency in OFDM systems

To improve the energy efficiency of power amplifier in OFDM systems, an adaptive polarization-QAM modulation scheme is proposed considering the data rate requirement variation at the transmitter. Since QAM and polarization modulation have different energy efficiency performance in the linear and nonlinear region of power amplifier respectively, thus the optimal energy efficiency can be obtained by combining the two modulation schemes together and adjusting their modulation order adaptively to fulfill the varying data rate requirement. The power series model of power amplifier is used to analyze the effects of both the in-band distortions and the out-of-band emissions on OFDM signals. Based on above, the proposed scheme can be formulated as an optimization problem regarding the output back off value as well as the modulation order of polarization modulation and QAM. Simulations under the same symbol error rate threshold and data rate requirement show that, the energy efficiency of the proposed scheme is nearly twice as that of the traditional QAM scheme in OFDM systems.

[1]  Abdolali Abdipour,et al.  Analysis of performance degradation due to non-linearity and phase noise in orthogonal frequency division multiplexing systems , 2010, IET Commun..

[2]  S.P. Stapleton,et al.  Digital predistortion linearizes wireless power amplifiers , 2005, IEEE Microwave Magazine.

[3]  Andreas Pascht,et al.  Power efficient transceivers to enable energy-efficient mobile radio systems , 2010 .

[4]  C. Tellambura,et al.  An Overview of Peak-to-Average Power Ratio Reduction Techniques for OFDM Systems , 2006, 2006 IEEE International Symposium on Signal Processing and Information Technology.

[5]  Davide Dardari,et al.  A theoretical characterization of nonlinear distortion effects in OFDM systems , 2000, IEEE Trans. Commun..

[6]  Sergio Benedetto,et al.  Multilevel polarization shift keying: optimum receiver structure and performance evaluation , 1994, IEEE Trans. Commun..

[7]  Chunyan Feng,et al.  An energy efficient Polarization Modulation scheme for nonlinear Power Amplifier , 2012, 2012 IEEE Globecom Workshops.

[8]  Dong Wei,et al.  An optimal pre-compensation based joint polarization-amplitude-phase modulation scheme for the power amplifier energy efficiency improvement , 2013, 2013 IEEE International Conference on Communications (ICC).

[9]  Dong Wei,et al.  A Polarization-Amplitude-Phase Modulation scheme for the Power Amplifier energy efficiency enhancement , 2012, The 15th International Symposium on Wireless Personal Multimedia Communications.

[10]  Dong Wei,et al.  Virtual Polarization Detection: A Vector Signal Sensing Method for Cognitive Radios , 2010, 2010 IEEE 71st Vehicular Technology Conference.

[11]  Weihua Zhuang,et al.  A Survey on Green Mobile Networking: From The Perspectives of Network Operators and Mobile Users , 2015, IEEE Communications Surveys & Tutorials.

[12]  Liesbet Van der Perre,et al.  Challenges and enabling technologies for energy aware mobile radio networks , 2010, IEEE Communications Magazine.

[13]  Tao Jiang,et al.  Effect of PAPR Reduction on Spectrum and Energy Efficiencies in OFDM Systems With Class-A HPA Over AWGN Channel , 2013, IEEE Transactions on Broadcasting.

[14]  Philip K. T. Mok,et al.  A Two-Phase Switching Hybrid Supply Modulator for RF Power Amplifiers With 9% Efficiency Improvement , 2010, IEEE Journal of Solid-State Circuits.