пятница, 3 сентября 2010 г.

OFDM, COFDM: CIS-59, Known as the "Ferrite", perhaps an experimental(inner) brand.

CIS-59, Known as "Ferrite", perhaps an experimental(inner) brand.
Ch-59, Br-40 Hz, Sh-50 Hz, QAM-64, k = 1/4 = 0.25




Author: SergUA6
Band Width ~3000 Hz
Low Range ~330 Hz
Baud Rate 40 Hz
n-Ary (PSK/MPSK) QAM-64
Count of Carriers 59
Step between carriers 50 Hz
ACF ~175 ms
RX mode SSB

Sonograms

pic.1 Generall view

Diagrams
pic.2 Phase constellation in the channel

pic.3 Synchronization symbols (every 7th symbol)

Pictures
pic.4 ACF

CIS-59 "Ferrite" - The name "Ferrite" quite possibly is not wide known. We can suppose it is an internal trade mark of the manufacturer. The manufacturer is unknown (at least to me), but it is known that it is domestic (Russian) development . The record has an exellent quality, all parameters are easily defined in SA.

I would like to mark some features of this signal, these are:
  1. special symbols the synchronization/adaptations (every seventh symbol).
  2. the form of constellation QAM-64 is characteristic more likely for NATO signals, than for signals CIS.

The maximum technical speed = 59 (quantity channels) *40 (clock frequency of manipulation) *6 (quantity of bits in one position QAM-64) minus synchronization symbols, that makes 14160 - (14160/7) ~ approximately 12137 bps.

The signal is generated by A model.

The detailed information about models/types of OFDM is in article/update version SA update to version 6.1.2.7 & OCG update to version 1.0.2.7