hello felix,
>>please remember to always reply to the list.
i'm sorry, i'm new at this. i have checked my configuration and i hope it works the next time.
to mix up the baseband signal to 12khz or higher to short wave (3-30mhz) should be the same procedure. i have tested it by using a multiply block and a signal source block as the carrier frequency.
but there is an other question: if i configured my system as described, can i be sure that the bandwidth of each sub carrier has the bandwidth and symbol duration as shown by the equations?
used_bw = occupied_carriers * df
df = used_bw / occupied_carriers = 10khz / 228
df = 43.86hz --> tsym = 22.8ms
it's very confusing why i have to adjust my used bw by changing the sampling rate. when i follow the equations and the standard i choose one mode (RM A, SO 3). that means i have to use 228 carriers
and have a symbol duration with 24ms which leads to 41.66hz carrier spacing. so the used bw is 228 * 41.66hz = 9.5khz (approx. 10khz). this bw should be fix and should not change by the sampling rate.
sorry for the maybe silly questions but i want to keep on that stuff.
@Marcus
you mean if there were pilots for a channel estimation in the transmitted signal?
alphonso