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question about pulse shaping filter in hart c8psk

I think there are inconsistencys in the C8PSK Physical Layer Specification. The pulse shaping filter is a raised cosine shaping with 0.5 roll-off factor. The speed of the transmition is 3.2kbps, so the 3db bandwidth of the channel is 1600Hz. The energy density couldn't satisfy the specification. The energy density at 800Hz and 5600Hz requested in the specification shall be attenuated 5db or 1db down (3db ± 2db) from the maximum energy density in the frequency band 800Hz to 5600Hz. Although the pulse filter couldn't limit the the energy density completely, the bandwidth of the channel must be less than the bandwidth of the filter. There is another inconsistance that the range of operational channel bandwidth is defined as 2.5KHz or greater. supposing that the range of operational channel bandwidth is 2.5KHz, and the modulated signal bandwidth is 800Hz to 5600Hz, so most of the signal is decreased. so I think the definitions of the pulse shaping filter's roll-off factor and the operational bandwith maybe not correct.
It's my question.
could you give me some answer.

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