# Altering the Galileo/Beidou Constellation Parameters without applying Custom Signal **URL:** \ **Category:** Skydel Discussion\ **Created:** [June 26, 2022, 6:05pm UTC](https://learn.safran-navigation-timing.com/t/altering-the-galileo-beidou-constellation-parameters-without-applying-custom-signal/707 "2022-06-26T18:05:44Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![mohdyaser](https://yyz2.discourse-cdn.com/flex030/user_avatar/learn.safran-navigation-timing.com/mohdyaser/32/422_2.png) [@mohdyaser](https://learn.safran-navigation-timing.com/u/mohdyaser)\ **Post date:** [June 26, 2022, 6:05pm UTC](https://learn.safran-navigation-timing.com/t/altering-the-galileo-beidou-constellation-parameters-without-applying-custom-signal/707/1 "2022-06-26T18:05:44Z")
So will the the Galileo/Beidou Constellation works normally if I make the altitude a LEO one, without applying custom signal? My receiver is not working. Theoretically, it should work, If it does, how? mine is not working. If not, why? ---
**Author:** ![Grace](https://avatars.discourse-cdn.com/v4/letter/g/f17d59/32.png) [@Grace](https://learn.safran-navigation-timing.com/u/Grace)\ **Post date:** [June 28, 2022, 9:53pm UTC](https://learn.safran-navigation-timing.com/t/altering-the-galileo-beidou-constellation-parameters-without-applying-custom-signal/707/2 "2022-06-28T21:53:42Z")
Hi @mohdyaser, Sorry for the delay. We believe the error you are experiencing is probably due to your GPS receiver settings. We did a quick test in our team with Galileo and Beidou satellites in LEO orbit as described in the application note without custom signals. We then used a Ublox F9 and U-center V20.10 to track the satellites. We are able to see the Galileo and Beidou signals as shown in the images below: ![Skydel Constellation tab](https://canada1.discourse-cdn.com/flex030/uploads/orolia/original/1X/7b1c133d4ff11600b48d4c90bb8cf9bbea038ef9.png) _Fig 1: Skydel constellation Tab view_ ![u-center 20.10 - Messages - UBX - NAV (Navigation) - SAT (Satellite Info](https://canada1.discourse-cdn.com/flex030/uploads/orolia/original/1X/2ee7ea841f33135a08f919a03ed116c306ee5a21.png) _Fig 2: Ublox UBX NAV SAT message_ ![UBX - RXM (Receiver Manager) - Satellites CN0](https://canada1.discourse-cdn.com/flex030/uploads/orolia/original/1X/c1dd2f22781e185cf201a06ef5a2f1eff960508e.png) _Fig 3: Ublox Satellite-level tracking_ Please, let us know what type of receiver you are using so that we can help you troubleshoot this issue. Regards ---
**Author:** ![mohdyaser](https://yyz2.discourse-cdn.com/flex030/user_avatar/learn.safran-navigation-timing.com/mohdyaser/32/422_2.png) [@mohdyaser](https://learn.safran-navigation-timing.com/u/mohdyaser)\ **Post date:** [June 29, 2022, 4:11am UTC](https://learn.safran-navigation-timing.com/t/altering-the-galileo-beidou-constellation-parameters-without-applying-custom-signal/707/3 "2022-06-29T04:11:07Z")
Hello @Grace No worries. My setup was using 4 galileo satellites as LEO as stated in the LEO constellation guide with the same exact parameters. And a ublox EVK-M8T and an updated U Center (don’t remember the exact version) ---
**Author:** ![Grace](https://avatars.discourse-cdn.com/v4/letter/g/f17d59/32.png) [@Grace](https://learn.safran-navigation-timing.com/u/Grace)\ **Post date:** [June 29, 2022, 8:06pm UTC](https://learn.safran-navigation-timing.com/t/altering-the-galileo-beidou-constellation-parameters-without-applying-custom-signal/707/4 "2022-06-29T20:06:19Z")
> My setup was using 4 galileo satellites as LEO as stated in the LEO constellation guide with the same exact parameters. And a ublox EVK-M8T and an updated U Center (don’t remember the exact version) Hey @mohdyaser, we did some testing with a Ublox M8T model and it seems that there are limitations with this model for low orbit GNSS satellites. The best we can advise you is to use another type of receiver to continue your test. Regards ---
**Author:** ![mohdyaser](https://yyz2.discourse-cdn.com/flex030/user_avatar/learn.safran-navigation-timing.com/mohdyaser/32/422_2.png) [@mohdyaser](https://learn.safran-navigation-timing.com/u/mohdyaser)\ **Post date:** [June 30, 2022, 5:47am UTC](https://learn.safran-navigation-timing.com/t/altering-the-galileo-beidou-constellation-parameters-without-applying-custom-signal/707/5 "2022-06-30T05:47:57Z")
I see. Which model do you suggest we get? Since generation 9 worked with you, generation 10 should work too right? ---
**Author:** ![Grace](https://avatars.discourse-cdn.com/v4/letter/g/f17d59/32.png) [@Grace](https://learn.safran-navigation-timing.com/u/Grace)\ **Post date:** [July 5, 2022, 2:47pm UTC](https://learn.safran-navigation-timing.com/t/altering-the-galileo-beidou-constellation-parameters-without-applying-custom-signal/707/6 "2022-07-05T14:47:55Z")
Hi @Mohamed, Indeed, Skydel always computes the right Doppler and Pseudorange values, whatever the orbit of the satellites. But some receivers may not be able to handle high dynamic range dopplers, as is the case for LEO satellites. It is possible that this model can work, but we advise you to check the specifications for the doppler and Pseudorange ranges. Regards