Talbot Andrew wrote:
[snip]
There seems to be no appreciation on this newsgroup of the real value of
coherent detection - that is, having phase information available when
the signal is decoded and coherently locking to the signal carrier and
bit timing. Simple theory, as I covered in a previous email, shows
mathematically the considerable theoretical advantage of coherent
detection over non coherent, there is no dispute about this.
[snip]
Andy,
from a theoretical point of view you are damn right. But I am
not so sure that LF/HF propagation can preserve phase coherence and
with it the decoding gain achieved with coherent detection, unless you are
willing to use some extra bandwidth to transmit phase information.
But, then, I am not a propagation expert, so my comments stop here.
73,
Alberto I2PHD
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