California Institute of Technology Assigned Patent

California Institute of Technology, Pasadena, CA, has been assigned a patent (9,983,808) developed by Li, Yue, College Station, TX, En Gad, Eyal, Pasadena, CA, Jiang, Anxiao, College Station, TX, and Bruck, Jehoshua, Pasadena, CA, for a “NAND flash reliability with rank modulation.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “The reliability of NAND flash memory decreases rapidly as density increases, preventing the wide adoptions of flash-based storage systems. A novel data representation scheme named rank modulation, (RM) is discussed for improving NAND flash reliability. RM encodes data using the relative orders of memory cell voltages, which is inherently resilient to asymmetric errors. For studying the effectiveness of RM in flash, RM is adapted to make it simple to implement with existing flash memories. The implementation is evaluated under different types of noise of 20 nm flash memory. Results show that RM offers significantly lower cell error rates compared to the current data representation in flash at typical P/E cycles. RM is applied to flash-based archival storage and shows that RM brings up to six times longer data retention time for 16 nm flash memory.”

The patent application was filed on December 10, 2015 (14/965,869).