Multiple scrambled layers for audio watermarking

A system to map a distribution scheme for encoding an audio signal with a watermark, the system comprising:

• a processor to execute computer readable instructions to:
• divide the watermark into a plurality of watermark symbols;
• map the watermark symbols to a plurality of frequency bins according to a first distribution scheme to create a plurality of watermark layers including a first watermark layer having a first combination of the frequency bins and a second watermark layer having a second combination of the frequency bins, the first combination of the frequency bins and the second combination of the frequency bins to partially overlap, subsets of adjacent ones of the plurality of frequency bins grouped into a corresponding plurality of frequency clumps;
• determine a sequence for shifting watermark symbols between the frequency clumps to cause different combinations of watermark symbols that include one watermark symbol from each watermark layer to share up to a first number of frequency bins, the first number of frequency bins to be less than a number of watermark symbols in respective ones of the different combinations;
• and
• generate a second distribution scheme to map the watermark symbols in accordance with the sequence;
• and
• a transceiver to communicate the second distribution scheme to a device.