Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-22T13:03:35.411Z Has data issue: false hasContentIssue false

4-Channel, time-domain measurement system using track and hold amplifier for the characterization and linearization of high-power amplifiers

Published online by Cambridge University Press:  17 November 2011

Sajjad Ahmed*
Affiliation:
University of Limoges, XLIM, UMR n 6172, 123, Av. A. Thomas, 87060 Limoges cedex, France.
Mohammad Saad El Dine
Affiliation:
University of Limoges, XLIM, UMR n 6172, 123, Av. A. Thomas, 87060 Limoges cedex, France.
Guillaume Neveux
Affiliation:
University of Limoges, XLIM, UMR n 6172, 123, Av. A. Thomas, 87060 Limoges cedex, France.
Tibault Reveyrand
Affiliation:
University of Limoges, XLIM, UMR n 6172, 123, Av. A. Thomas, 87060 Limoges cedex, France.
Denis Barataud
Affiliation:
University of Limoges, XLIM, UMR n 6172, 123, Av. A. Thomas, 87060 Limoges cedex, France.
Jean-Michel Nebus
Affiliation:
University of Limoges, XLIM, UMR n 6172, 123, Av. A. Thomas, 87060 Limoges cedex, France.
*
Corresponding author: Sajjad Ahmed Email: [email protected]

Abstract

We propose in this paper a 4-channel time-domain test bench for the characterization and linearity enhancement of microwave power amplifiers (PAs). The proposed time-domain measurement system utilizes four track and hold amplifiers (THAs) for direct subsampling of radiofrequency (RF) signals. The use of wideband THAs to replace samplers or mixers enables reducing analog IF circuit complexity. It permits direct digitization of RF signals like CW, two-tone and pulsed modulated signals, bringing more flexibility in the receiver's performance by enhancing the dynamic range and bandwidth. This test bench is capable of completely extracting the phase, amplitude, and transfer characteristics of non-linear devices excited with CW or modulated RF signals. In this work, two-tone transfer characteristics of a 50 W GaN HEMT Nitronex PA were extracted and processed for applying digital pre-distortion linearization to enhance linearity performance. Time-domain envelope and carrier waveforms (voltage and current) along with third-order inter-modulation distortion (IMD) products with and without digital pre-distortion scheme are also presented.

Type
Research Papers
Copyright
Copyright © Cambridge University Press and the European Microwave Association 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1]Tasker, P.J.: Practical waveform engineering, in IEEE Microw. Mag., December 2009, 6576.CrossRefGoogle Scholar
[2]Faraj, J.; Callet, G.; De Groote, F.; Verspecht, J.; Quere, R.; Teyssier, J.P.: Burst of pulses for time domain large signal measurements, ARFTG Int. Microwave Symp., Boston, USA, 2009, 14.Google Scholar
[3]Ahmed, S., Saad-el-Dine, M.; Neveux, G.; Reveyrand, T.; Barataud, D.; Nebus, J.: Time-domain measurement system using track and hold amplifier applied to pulsed RF characterization of high power GaN devices, in IEEE Int. Microwave Symp., Baltimore, 2011, 14.Google Scholar
[4]Williams, D.J.; Leckey, J.; Tasker, P.J.: Envelope domain analysis of measured time-domain voltage and current waveforms provide for improved understanding of factors effecting Linearity, in 2003 IEEE Int. Microwave Symp., 2003, 14111414.CrossRefGoogle Scholar
[5]Clark, C.J.; Chrisikos, G.; Muha, M.S.; Moulthrop, A.A.; Silva, C.P.: Time-domain envelope measurement technique with application to wideband power amplifier modeling. IEEE Trans. Microw. Theory Tech., 46 (12) (1998), 25312540.CrossRefGoogle Scholar
[6]El Yaagoubi, M. et al. : Time-domain calibrated measurements of wideband multisines using a large-signal network analyzer. IEEE Trans. Microw. Theory Tech., 56 (5) (Part 1) (2008), 11801192.CrossRefGoogle Scholar
[7]Van Moer, W.; Rolain, Y.: An improved broadband conversion scheme for the large-signal network analyzer. IEEE Trans. Instrum. Meas., 58 (2) (2009), 483487.CrossRefGoogle Scholar
[8]El Yaagoubi, M.; Neveux, G.; Barataud, D.; Nebus, J.M.; Verspecht, J.: Accurate phase measurements of broadband multitone signals using a specific configuration of a large signal network analyzer, in Microwave Symp. Digest, 2006 IEEE MTT-S International, June 2006, 14481451.CrossRefGoogle Scholar
[9]Abouchahine, M. et al. : Broadband time-domain measurement system applied to the characteristics of cross modulation in nonlinear microwave devices. IEEE Trans. Microw. Theory Tech., 58 (4) (2010), 10381045.CrossRefGoogle Scholar
[10]Gand, X.U.; Jiren, Y.: Comparison of charge sampling and voltage sampling, in 43rd IEEE Midwest Symp. Circuits and System, Lansing, MI, November 8, 2000, 1, 440443.Google Scholar
[11]Yamanaka, S.; Sano, K.; Murata, K.: A 20-Gs/s track and hold amplifier in InP HBT technology. IEEE Trans. Microw. Theory Tech., 58 (9) (2010), 23342339.CrossRefGoogle Scholar
[12]Verspecht, J.: Calibration of a measurement system for high frequency non-linear devices. Doctoral Dissertation. Vrije universiteit, Brussel, November 1995.Google Scholar
[13]Saad El Dine, M. et al. : A Measurement set-up and methodology combining dynamic biasing and baseband predistortion for high efficiency and linear amplifier design, in Int. Microwave Symp., Boston, USA, 2010, 14.Google Scholar
[14]Weiß, M.: Measuring the dynamic characteristic of high- frequency amplifiers with real signals, in European Wireless 2000, Dresden, September 2000, 6771.Google Scholar
[15]Nitronex NPTB00050 Datasheet, NDS-007 Rev. 2, May 2009, available at http://www.nitronex.comGoogle Scholar
[16]Teikari, L.: Digital predistortion linearization methods for RF power amplifiers. Doctoral Dissertation. Helsinki University of Technology, September 26, 2008.Google Scholar
[17]Morris, K.A.; McGeehan, J.P.: Gain and phase matching requirements of cubic pre-distortion systems. Electron. Lett, 36 (21) (2000), 18221824.CrossRefGoogle Scholar
[18]Giesbers, D.; Mann, S.; Eccleston, K.: Adaptive digital pre-distortion linearization for RF power amplifier, in 13th Electronics New Zealand Conf. (ENZCON2006), November 13–14, 2006, 244248.Google Scholar