Surveillance Processing Algorithms for the DABS Mode of BCAS have been implemented in software for the non-real time processing of air-to-air link data. The data to be processed may be either AMF recorded air-to-air data, or data derived from simulated flight encounters. Examples of simulation trials for a specific collision encounter are presented with illustrate the impact of increased ATCRBS fruit levels upon the performance of the surveillance processor. This document also provides detailed definitions of the surveillance processing algorithms.