воскресенье, 20 сентября 2009 г.

OFDM Signal: MSM-1250

Thales "SkyFax", RC5000 series - Javelin
Author: SergUA6 6.0
Band Width ~2400-2500 Hrz
Low Range ~600 Hrz
Baud Rate 125 Hrz in the channel
Count of Carriers 10 channels FSK-2 with frequency spacing 125 Hz
Step between carriers 250 Hrz between centers of the channelers
RX mode SSB

The example of this signal is here.


pic.1 General look

pic.2 Speed of manipulation

pic.3 Detalization

MSM-1250 - the signal is 100% generated with usage of OFDM technologies, and it do not getting under MFSK In Reallyty, there is no problems to form not only similar signals, but also any multistrip(multi-band) signals with usage IFFT, as becomes in practice in 99.99 % percent of cases.

Certainly, any of prefixes are not used here, because there is no necessity in it, since there are no problems
with synchronisation , owing to the selected sort of manipulation and synchronism of transactions on all channels.

Besides, the spectrum is used with not maximum density, as there are "holes" with width ~ 125hrz between
channels "holes" in width of 125 hertz, because of the selected sort of manipulation. Technical speed of the
whole stream is 125*10 = 1250 bps, as it is reflected in The name of the signal.