Useful Characteristics for Controlling the Cancellation Performance and Center Frequency of a Linearization Loop

ETRI Journal

关键词: delay mismatch;    phase imbalance;    amplitude imbalance;    Linearization;   

Others  :  1185449
DOI  :  10.4218/etrij.06.0204.0048

【 摘 要 】

The cancellation performance of a linearization loop is limited by the degree of an amplitude imbalance and a phase imbalance. A delay mismatch causes a phase variation as a function of frequency. Therefore, the cancellation performance and linearization bandwidth are limited by a delay mismatch. The expression for the effects of an amplitude imbalance, a phase imbalance, and a delay mismatch on the characteristics of a linearization loop is derived and analyzed. The simulation results are compared with the results obtained by means of using a commercial simulation tool and the exact agreement is reported. The derived equation could be used in designing a linearization loop and predicting the cancellation performance of the linearization loop usefully. Some useful characteristics, known from the simulation results obtained by using the derived equation, of a linearization loop for designing and implementing feedforward amplifiers are described in detail.

   

【 参考文献 】

• [1]Frederick H. Raab, Peter Asbeck, Steve Cripps, Peter B. Kenington, Zoya B. Popovic, Nick Pothecary, John F. Sevic, and Nathan O. Sokal, "Power Amplifiers and Transmitters for and Microwave," IEEE Trans. Microwave Theory Tech., vol. 50, no. 3, Mar. 2002,
• [2]James K. Cavers, "Adaptation Behavior of a Feedforward Amplifier Linearizer," IEEE Trans. Vehicular Tech., vol. 44, no. 1, Feb. 1995, pp. 31-40.
• [3]Peter B. Kenington, High-linearity RF Amplifier Design, Artech House, 2000.