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Mr. E
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Re: Dec 4 - DAY 2: 802.15.4 Radio Link Modulation
Mr. E   12/4/2012 2:41:54 PM
NO RATINGS
@Paul: concerning the unique decoding of chips: I expected to see limited repeated sequences of 0s or 1s so that synchronization could be more easily maintained. In some modulation schemes bit stuffing is used to do this. However, I also expected to see unique overall sequencing of groups of 0s and 1s in the chip values for each of the data symbols. This is apparently not the case. For example, at 915MHz on slide 14, the chip values for data symbol 9 are identical to those for data symbol 8, but two bit times later (9's chip values lag those of 8 by 2 bit times). So 8 starts 01101 and 9 starts 0001101. I would think this would cause problems maintaining sync. Are there other symbols that resync the bit values that make up the chips?



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