123zxc123
Newbie level 2
I`m now designing a modulator,according to teh protocol,after the root - raised - cosine filter,I、Q will be modulated by a sinewave with a frequency 3200Hz.
Blow is the requirements of the protocol:
"The energy density at 800Hz and 5600Hz shall be attenuated 3dB +/- 2dB down form the maximum energy density in the frequency band 800Hz
to 5600Hz."
But in my design, symbol rate is 3200Bps,roll-off factor,r is 0.5,then I can`t understand that ,based on bandwidth formula (1+r)/2T,(T is symbol period),at the frequency of 2400Hz attenuated too much that can`t stasify the specfication of protocol.Who can tell how to solve this problem,thank you.\]
Blow is the requirements of the protocol:
"The energy density at 800Hz and 5600Hz shall be attenuated 3dB +/- 2dB down form the maximum energy density in the frequency band 800Hz
to 5600Hz."
But in my design, symbol rate is 3200Bps,roll-off factor,r is 0.5,then I can`t understand that ,based on bandwidth formula (1+r)/2T,(T is symbol period),at the frequency of 2400Hz attenuated too much that can`t stasify the specfication of protocol.Who can tell how to solve this problem,thank you.\]
