On 02/23/2010 10:22 PM, John B. Stephensen wrote: > These modes use interleaving and randomize data values by > exclusive-ORing with a pseudorandom binary sequence. The methods are > used in most commerial products and the FCC and NSA know how to monitor > the signals.
However, this does result in carrier placement also being somewhat randomized. Maybe not in exactly the same way as true spread spectrum, since the carrier position is still somewhat dependent on the data content. On the other hand, from the ROS documentation it appears that the carrier location in ROS is also still dependent on data content (as well as a pseudo-random sequence). Carrier location it ROS is, as far as I can tell (Jose will know for sure), dependent on both the data being transmitted and the pseudo-random sequence being used. > The FCCs problem is that the military uses FHSS and DSSS to hide the > existance and content of their transmissions thus preventing the > monitoring that the FCC is required to do of amateur signals. That could be a problem with ROS, as long as the protocol specification is unknown. However, once the protocol has been finalized and the specification made public, monitoring ROS communications will be easy. -- All rights reversed.
