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Jim Frame

Well-Known Member
Are there any downsides to doing this? Is there a performance hit with 4-constellation firmware versus 2-constellation?
 

Shawn Billings

Shawn Billings
5PLS
I don't know of any testing that has been done with single frequency Galileo and Beidou. I can only guess at the performance improvement.
 

Steve Hankins

Active Member
5PLS
Maybe an example exactly where "in the bottom part of the window" to enter the command?
Thoughts? Maybe I am missing something with the GREIS command?
 

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Jim Frame

Well-Known Member
I note that the GREIS manual doesn't show 1571 as an option for the l1center value. Here's what it says about L1 center frequencies when using this command:

1575 – This is default. BeiDou B1 reception is impossible. Best GPS/GALILEO/ SBAS/QZSS L1/E1 performance. Best multipath reduction in mpnew mode.

1573 – BeiDou B1 reception is possible, but it's data quality is poor. Good GPS/GALILEO/SBAS/QZSS L1/E1 performance. Good GPS/GALILEO/SBAS/QZSS multipath reduction in mpnew mode. Recommended for lowprecision BeiDou B1 applications and/or for collecting BeiDou navigation data.

1563 – BeiDou B1 reception is good, it's data quality is good. Good BeiDou multipath reduction using "mpnew" setting. Poor GPS/GALILEO/SBAS/QZSS L1/E1
performance. Recommended for high-precision BeiDou B1 applications.

It sounds to me that even if 1571 will work, you might sacrifice some performance with other constellations. I'm wondering if it's worth it.
 
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Steve Hankins

Active Member
5PLS
I note that the GREIS manual doesn't show 1571 isn't shown as an option for the l1center value. Here's what it says about L1 center frequencies when using this command:

1575 – This is default. BeiDou B1 reception is impossible. Best GPS/GALILEO/ SBAS/QZSS L1/E1 performance. Best multipath reduction in mpnew mode.

1573 – BeiDou B1 reception is possible, but it's data quality is poor. Good GPS/GALILEO/SBAS/QZSS L1/E1 performance. Good GPS/GALILEO/SBAS/QZSS multipath reduction in mpnew mode. Recommended for lowprecision BeiDou B1 applications and/or for collecting BeiDou navigation data.

1563 – BeiDou B1 reception is good, it's data quality is good. Good BeiDou multipath reduction using "mpnew" setting. Poor GPS/GALILEO/SBAS/QZSS L1/E1
performance. Recommended for high-precision BeiDou B1 applications.

It sounds to me that even if 1571 will work, you might sacrifice some performance with other constellations. I'm wondering if it's worth it.
Thank you for the reply and information. I guess the weekend was not the best time to experiment with this, as i am out of my comfort level. With the information you have provided, I also wonder if it's worth it. I will wait for some input from Matt or Shawn before proceeding. Thank you again for the help!
 

M Kulish

New Member
Steve, I think if you drop the leading % on the command input it should be accepted.
so paste set,/par/l1center/frq,1571 instead of %set,/par/l1center/frq,1571

MK
 

Jim Frame

Well-Known Member
As I read the manual, the % sign is the statement identifier, which forces the receiver to generate a response. It's optional.
 

Matt Johnson

Well-Known Member
5PLS
Steve, I think if you drop the leading % on the command input it should be accepted.
so paste set,/par/l1center/frq,1571 instead of %set,/par/l1center/frq,1571

MK

Yes, it should be either

%print,/par/l1center/curfrq%

or

print,/par/l1center/curfrq


9895
 

Steve Hankins

Active Member
5PLS
The print command can be used to check what the center frequency setting.
Matt:
I am unable to replicate your provided NetView screen? At Parameters/Positioning I enter %set,/par/|1center/frq,1571% and then click the green apply check symbol, it saves, then enter %print,/par/|1center/curfrq% and it returns %print,/par/|1center/curfrq% ok, but does not show the 1571? If I reboot I get the same scenario. I see the additional constellations of GAL and BDS remain checked after the reboot, but it appears I may not have changed the center frq. What am I missing?
 

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