THE GOAL OF THIS PROPOSAL IS TO DEVELOP TECHNOLOGY THAT CAN DIRECTLY DETERMINE THE IMPACT OF SYSTEM DESIGN ON THE SCIENCE DELIVERABLES: MEASUREMENTS OF THE HI POWER SPECTRUM AND IN TURN CONSTRAINTS ON COSMOLOGICAL AND ASTROPHYSICAL PARAMETERS. THIS TECHNOLOGY WILL CONSIST OF A SOFTWARE SUITE FOR END-TO-END SIMULATION OF THE ENTIRE INSTRUMENT AND PIPELINE: ENCOMPASSING ASPECTS FROM ANTENNA DESIGN TO SOURCES OF SYSTEMATIC ERRORS LIKE MUTUAL COUPLING OF ELEMENTS AND CROSS-TALK THROUGH TO THE ANALYSIS TOOLS USED. MY RESEARCH GROUP HAS EXPERIENCE AT THE FOREFRONT OF ALL THESE ASPECTS OF HI COSMOLOGY EXPERIMENTS; THE WORK TO BE PROPOSED HERE FOCUSES ON UNIFYING OUR MOST ADVANCED UNDERSTANDING OF THESE ISSUES INTO ONE FRAMEWORK.