Power Aware Post-Manufacture Tuning of MIMO Receiver Systems

This paper presents a methodology for post-manufacture tuning of MIMO (Multiple-Input-Multiple-Output) wireless systems aimed at increasing device manufacturing yield under large process variations. The goal is to achieve specified system-level EVM (Error Vector Magnitude) targets for MIMO receiver systems by tuning the individual MIMO receiver subsystems whose combined gain, noise and nonlinearity parameters determine the overall system-level EVM metric. While there has been prior work on tuning of SISO systems, the current work is novel due to the fact that the performances of individual receiver subsystems can combine in different ways to result in the same system-level EVM value. As the systems are tuned to meet the system level end-to-end metric it is ensured that all devices that are tuned for EVM consume the least amount of power possible. Tuning infrastructure for MIMO receivers and underlying tuning algorithms are developed in this work. A 1×2 MIMO system for a 2.4 GHz OFDM WLAN is used to demonstrate the core ideas of this research. This work demonstrates a 23% increase in yield of the device with an average power increase of 9.18% for the system under consideration.