[time-nuts] WWVB Response

[Chuck Harris]

The more likely problem is the "designer" of the new
modulation has written patents that sew up every way
they can think of to demodulate the signal.  If they
did a good job with the patent, you won't be able to
design a receiver that demodulate the signal without
patent infringement.

-Chuck Harris

Peter Monta wrote:
> Hi John,
>
> Thank you for clarifying the openness of the transmission format.
> Could I ask whether there is any scenario under which aspects of the
> signal transmission design might be patented?  If companies or
> individuals wish to patent aspects of receiver design, that's fine,
> but I'd be uncomfortable with a patent-encumbered transmission format.
>
>> ... It is an unfortunate consequence of improving the reception
>> capability of our broadcast that this segment of our loyal user base are so
>> adversely affected.  The decision to proceed was not taken lightly, but in
>> the end it was decided that the improvement in reception capability
>> (especially along the JJY interference prone East Coast) outweighed the loss
>> of use of existing PLL devices.
>
> I suppose it's a matter of balancing the value of the PLL receivers
> and the loss of BPSK signal power to the residual carrier.  If the
> power loss is small, though, say 0.5 dB or below, then given the large
> process gains of the advanced receivers, it might be worth
> considering.  I don't imagine that the mere presence of residual
> carrier has any effect on the advanced receivers (since it is similar
> to interference from MSF and JJY, as you say), but please correct me
> if I'm wrong.
>
> Cheers,
> Peter