Cracking the complexity of fixed-point refinement in complex wireless systems

Fixed-point arithmetic leads to efficient implementations. However, the optimization process required to size each of the implementation signals can be prohibitively complex. In this paper, we introduce a new divide-and-conquer method that is able to approach the quality of global methods in significantly less time. Firstly, our method sorts the signals in multiple groups considering the propagation path of the signals to the global application metric (i.e., bit-error rate). Then, the fixed-point configurations of the groups are resolved with fast local simulations. Finally, the global fixed-point configuration is composed by the group configurations using slow global simulations. The method is applied to the fixed-point refinement of an advanced wireless algorithm achieving close to 9 times speedup with respect to a reference statistical method without affecting the quality of the result.