## Main Article Content

## Abstract

Efficient power amplifiers are essential in portable battery-operated systems such as mobile phones. Also, the power amplifier (PA) is the most power-consuming building block in the transmitter of a portable system. This paper investigates how the efficiency of the power amplifier (which is beneficial for multiple applications in communcation sector) can be improved by increasing the efficiency of switching mode class E power amplifiers for frequencies of 900 MHz and 1800 MHz. The paper tackles modeling, design improvements and verification through simulation for higher efficiencies. This is the continuation of previous work by the authors. These nonlinear power amplifiers can only amplify constant-envelope RF signals without introducing significant distortion. Mobile systems such as Advanced Mobile Phone System (AMPS) and Global System for Mobile communications (GSM) use modulation schemes which generate constant amplitude RF outputs in order to use efficient but nonlinear power amplifiers. Improvements in designs are suggested and higher efficiencies are achieved, to the tune of 67.1% (for 900 MHz) and 67.0% (1800 MHz).

## Keywords

## Article Details

*How to Cite*

*The Journal of Engineering Research [TJER]*,

*8*(1), 74–82. https://doi.org/10.24200/tjer.vol8iss1pp74-82

* * References

- Berglund, B., Johansson, J. and Lejon, T., 2006, "High Efficiency Power Amplifiers," Ericsson Review No. 3, pp. 92-96.
- Dhawyani, M., Mahrooqi, Q., Rahbi, F., Kalbani, A., Touati, F. and Nadir, Z., 2008, "Improvement in the Efficiency of Class-E Power Amplifier for RF," IEEE 5th Int. Multi Conference on Systems, Signals and Devices, (SSD'08), pp. 491-495, Jordan.
- Larcher, L., Brama, R., Ganzerli, M., Iannacci, J., Margesin, B., Bedani, M. and Gnudi, A., 2009, "A MEMS Reconfigurable Quad-Band Class E power amplifier for GSM Standard," IEEE 22nd Int. Conference on Micro Electro Mechanical Systems, (MEMS'09), pp. 864-867, Australia.
- Lee, T., 2004, "The Design of CMOS Radio- Frequency Integrated Circuits," ISBN 13- 9780521835398, Cambridge University Press, UK.
- Nadir, Z. and Touati, F., 2009, "Design of High Efficiency Switching Mode Power Amplifier for RF and Microwave," IEEE 16th Int. conference on Telecommunications (ICT'09), pp. 329-333, Morocco.
- Razafi, B., 1998, "RF Microelectronics," ISBN:0-13- 887571-5, Prentice Hall, USA.
- Sokal, N. and Sokal, A., 1975, "Class E-A New Class of High Efficiency Tuned Single-Ended Switching Power Amplifiers," IEEE J. Soild-State Circuits, Vol. 10(3), pp. 168-176.
- Su, D. and McFarland, W., 1998, "An IC for Linearizing RF Power Amplifiers Using Envelope Elimination and Restoration," IEEE J. of Solid State Circuits, Vol 33(12), pp. 2252-2258.
- Yoo, C. and Huang, Q., 2001, "A Common Gate Switched 0.9W Class E Power Amplifier with 41% PAE in 0.25- m CMOS," IEEE J. of Solid State Circuits, Vol. 36(5), pp. 823-830.

#### References

Berglund, B., Johansson, J. and Lejon, T., 2006, "High Efficiency Power Amplifiers," Ericsson Review No. 3, pp. 92-96.

Dhawyani, M., Mahrooqi, Q., Rahbi, F., Kalbani, A., Touati, F. and Nadir, Z., 2008, "Improvement in the Efficiency of Class-E Power Amplifier for RF," IEEE 5th Int. Multi Conference on Systems, Signals and Devices, (SSD'08), pp. 491-495, Jordan.

Larcher, L., Brama, R., Ganzerli, M., Iannacci, J., Margesin, B., Bedani, M. and Gnudi, A., 2009, "A MEMS Reconfigurable Quad-Band Class E power amplifier for GSM Standard," IEEE 22nd Int. Conference on Micro Electro Mechanical Systems, (MEMS'09), pp. 864-867, Australia.

Lee, T., 2004, "The Design of CMOS Radio- Frequency Integrated Circuits," ISBN 13- 9780521835398, Cambridge University Press, UK.

Nadir, Z. and Touati, F., 2009, "Design of High Efficiency Switching Mode Power Amplifier for RF and Microwave," IEEE 16th Int. conference on Telecommunications (ICT'09), pp. 329-333, Morocco.

Razafi, B., 1998, "RF Microelectronics," ISBN:0-13- 887571-5, Prentice Hall, USA.

Sokal, N. and Sokal, A., 1975, "Class E-A New Class of High Efficiency Tuned Single-Ended Switching Power Amplifiers," IEEE J. Soild-State Circuits, Vol. 10(3), pp. 168-176.

Su, D. and McFarland, W., 1998, "An IC for Linearizing RF Power Amplifiers Using Envelope Elimination and Restoration," IEEE J. of Solid State Circuits, Vol 33(12), pp. 2252-2258.

Yoo, C. and Huang, Q., 2001, "A Common Gate Switched 0.9W Class E Power Amplifier with 41% PAE in 0.25- m CMOS," IEEE J. of Solid State Circuits, Vol. 36(5), pp. 823-830.