Wireless LAN technology for engine control and PHM

RLW, Inc. contracted with GE Aircraft Engines on behalf of NASA to conduct a tradeoff study comparing available and evolving wireless local area network (WLAN) technologies for applicability to gas turbine engine control functions. A variety of WLAN technologies were surveyed and compared for their performance relative to a number of critical to quality (CtQ) factors defined by the customer. Each of the CtQs were assigned a weighting factor and technologies were assigned a figure of merit (FoM) against each of the CtQs. A spreadsheet model was constructed to allow rapid conduct of sensitivity studies to assess the effects of CtQ weighting and technology FoM on a rank-order comparison of the technologies. The study initially focused on both physical/medium access control (MAC) technologies and on application-level protocol technologies that could use a variety of physical/MAC technologies. The study was finally limited to assess only physical/MAC technologies including: IEEE 802.11a, IEEE 802.11b, HomeRF2, Bluetooth, and HiperLAN/2. This paper describes the CtQ factors considered, each of the WLAN technologies, the spreadsheet model developed to conduct tradeoff studies, and the rank-order selection of the candidate technologies, identifying several viable options for consideration for engine applications.