1. An apparatus comprising: an input-to-index (I2I) module that maps a complex input into a real signal; a real data tap delay line that is coupled to the I2I module, wherein the real data tap line includes N delay elements; a complex data tap delay line that is configured to receive the complex input, wherein the complex data tap delay line includes M delay elements; a set of K non-linear function modules, each non-linear function module from the set has at least one real input, at least one complex input, and at least one complex output; and a configurable connectivity crossbar multiplexer that couples K of the N real tap delay line elements to real inputs of the set non-linear functions and that couples K of the M complex tap delay line elements to complex inputs of the set non-linear function modules.