@Paul: Wow! Better hope our clocks are stable. By the way, I now note that the relationship between the chip values for 8 and 9 is not unique: every single row in the table is the row above it shifted right by 2.
The Lecturer appears to have limited this lecture to a 6 year old version (year 2006) of the IEEE 802.15.4 standard. The year 2011 version (IEEE 802.15.4 - 2011) has many more modulation types and frequency bands defined in the standard. And since the year 2011 release, several more have been defined in the 802.15.4f and 802.15.4g standards.
@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?
@Paul: slide 15 shows 15 chip values c0 to c14 for each input bit but the text above the table says that a "16 bit chip" is in use. Is there a missing or assumed bit to make the 16th bit in the chip value?
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A slew of announcements about new materials and design concepts for transportation have come out of several trade shows focusing on plastics, aircraft interiors, heavy trucks, and automotive engineering. A few more announcements have come independent of any trade shows, maybe just because it's spring.
Samsung's Galaxy line of smartphones used to fare quite well in the repairability department, but last year's flagship S5 model took a tumble, scoring a meh-inducing 5/10. Will the newly redesigned S6 lead us back into star-studded territory, or will we sink further into the depths of a repairability black hole?
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