System and method for digitally correcting a non-linear element

Abstract

System and methods for a digital linearization of a non-linear element. Preferred embodiments provide digital predistortion methods and circuitry that addresses long or 'memory' effects and separately shorter duration effects, these two predistortion functions are operated together in an adaptive fashion with a non-linear element to provide a highly linear system. A long predistortion block comprises a plurality of configurable parallel coupled memory blocks, each further comprising a programmable nonlinearity, variable delays, digital filters, and signal combiners. These parallel blocks are selectively configured to provide a parallel filter, a Hammerstein filter and a compound Volterra filter. The parallel coupled memory blocks include programmable parameters that enable real time adaptation of the predistortion; the delay elements also include variable delays. The combined system of the predistortion circuitry and a non-linear element has a linear input-output signal response. Methods for initializing, parameterizing and adapting the system are disclosed.