Moin, On Mon, 3 Dec 2018 18:11:30 -0800 "Tom Van Baak" <[email protected]> wrote:
> At long last, a complete WWVB 60 kHz BPSK dev board is available: > > https://universal-solder.ca/product/everset-es100-cob-wwvb-60khz-bpsk-receiver-kit-with-2-antennas/ > > Note it includes the antenna(s). Also has links to documentation. As this is becoming a topic again, and the EverSet people still claim that the BPSK modulation of WWVB makes it more resilient to jamming and easier to receive, I would like to restate what I've written some years ago [1,2]: BPSK by itself does not improve timing. At most it improves reception by having a constant power envelope. But in case of WWVB, where the AM modulation is still kept, this is not the case. The phase changes do not help reception at all. In order to help reception, one needs to send a _known_ bit string in order for a corrolator in the receiver to pick the signal out of the noise. The only known bits in the BPSK signal are the first 12 bits of each minute. Compare this to DCF77 which encodes 512 bits every _second_. Ie while DCF77 gets something like 10-20dB easier to pick out of noise, but when using BPSK, WWVB gets... uhmm.. zero improvement. All the BPSK modulation of WWVB does is 1) Make the signal unusable for any carrier phase tracking receiver 2) Add a second type of bit stream onto the signal for additional information to be encoded 3) Generate a revenue stream for companies who sell new WWVB receivers. For more information, read [2] Attila Kinali [1] https://www.febo.com/pipermail/time-nuts/2013-July/060456.html [2] https://www.febo.com/pipermail/time-nuts/2013-July/060471.html -- <JaberWorky> The bad part of Zurich is where the degenerates throw DARK chocolate at you. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
