Thanks everyone. The Meinberg is nice and maybe available from Ebay by Alex's link. But its 35.42 much as the Odetics down converter. I am looking to create a 75.42 Mhz IF. Mini-circuits makes just the right parts. But had several IF bandwidths available. So will go with the 2 or so MHz filter as suggested.
I have the typical GPS better quality high gain antenna 1/2" Heliax feed to a low noise gain block that makes up for the loss of a 8 X splitter. I may add a 1575 filter ahead of the 10 db amplifier and then hit the mixer. I think I have a filter. I actually question that I need the filter or 10 db amp. May build without it to see what happens. Can easily add it. The LO will be a mini-circuits dsn-2036 followed by a 10 db amp to drive the mixer another mini-circuit DBM. The IF drives a bpf-a76+ and then will follow that with 30 db of gain at 75 MHz. At least thats my thinking. Regards Paul WB8TSL On Tue, Dec 1, 2015 at 1:36 AM, Magnus Danielson <[email protected] > wrote: > Hi, > > This is a side-track to Pauls original question, but maybe a nice little > point to make now that Peter touched on the subject. > > To elaborate a little on C/A and multipath surpression. > The multipath surpression of the receiver depends on code rate, bandwidth > and correlator spacing. P-code is able to surpress more, and the C/A code > errors look about the same as the P-code, but scaled accordingly. > Increasing the bandwidth helps to reduce the C/A errors, but taking the > next step of using narrow correlators further reduces the error. This is > shown already in the classical Spiliker book, but further readings from > Novatel could be nice. > > Increasing the bandwidth and narrowing the early and late correlator taps > both have the effect of reducing the time over which energy goes into the > E-L difference, and hence reducing the impact of multipath into the > solution. > > Cheers, > Magnus > > > On 12/01/2015 06:00 AM, Peter Monta wrote: > >> >>> What should the IF pass band bandwidth be? >>> >>> >> For GPS C/A with wide correlator, about 2 MHz; if you want Galileo BOC and >> (eventually) GPS L1C, or legacy C/A with narrow correlator, about 8 MHz; >> for GPS P code about 20 MHz. Books on GNSS software receivers will detail >> the many tradeoffs available---if you're starting out with a >> proof-of-concept lab receiver, go for 8 MHz. >> >> Cheers, >> Peter >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
