Article ID: 000092819 Content Type: Errata Last Reviewed: 11/03/2022

Why does the O-RAN Intel® FPGA IP give incorrect values when the Mu-law compression is turned on?

Environment

  • Intel® Quartus® Prime Pro Edition
  • BUILT IN - ARTICLE INTRO SECOND COMPONENT
    Description

    Due to a problem in the O-RAN Intel® FPGA IP version 1.8.0 and earlier, you may see the O-RAN Intel FPGA IP gives incorrect values when the Mu-law compression is turned on.

    When the compressed IqWidth and the original PRB value combination match as per below, the O-RAN Intel FPGA IP may generate an incorrect value of compressed PRB.

    IqWidth 8: Original PRB Value 0xFFC0
    IqWidth 9: Original PRB Value 0xFFE0
    IqWidth 10: Original PRB Value 0xFFF0
    IqWidth 11: Original PRB Value 0xFFF8
    IqWidth 12: Original PRB Value 0xFFFC
    IqWidth 13: Original PRB Value 0xFFFE
    IqWidth 14: Original PRB Value 0xFFFF

    For example, the original PRB value "0xFFF8" is compressed to 11 bits with comp Shift value '0' and the compressed PRB value is incorrectly generated as 0 (0x0). The correct compressed PRB value should be -1 (0x7FF).

    The Fronthaul Compression Intel® FPGA IP has the same problem.

    Resolution

    This problem is scheduled to be fixed in the O-RAN Intel® FPGA IP Version 1.8.1 and the Fronthaul Compression Intel FPGA IP 1.0.4.

    Related Products

    This article applies to 6 products

    Intel Agilex® 7 FPGAs and SoC FPGAs
    Intel® Arria® 10 FPGAs and SoC FPGAs
    Intel® Stratix® 10 DX FPGA
    Intel® Stratix® 10 GX FPGA
    Intel® Stratix® 10 MX FPGA
    Intel® Stratix® 10 SX SoC FPGA