Linearization of an Outphasing Amplifier for Wide-band Multi-carrier Signals

A novel method using self-organizing maps to determine the optimum ranges to partition the vector switched Volterra series is presented. Analyzing characteristics of the input signal it is possible to separate different regions of operation. Partitioning of the correction algorithm provides the ability to target regions of different non-linear behavior with separate coefficients. This work is validated with experimentally measured results and shows an adjacent channel power ratio (ACPR) of -49/-50 dBc achieved for a four carrier Wideband Code-Division Multiple Access (WCDMA) signal using a 19 watt digital outphasing amplifier from NXP.

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