why some devices using two GPS devices on the same board?

Discussion in 'Wireless & RF Design' started by Mans A, Aug 13, 2019.

  1. Mans A

    Thread Starter New Member

    Aug 13, 2019
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  2. jpanhalt

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    Jan 18, 2008
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    Welcome to AAC.

    Maybe it is to improve accuracy.

    Source: https://www.forbes.com/2002/02/15/0215tentech.html#4b897eec7010
     
  3. Wolframore

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    Jan 21, 2019
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    Dual gps modules work on two different bands and the two signals are compared for error correction. Current accuracy is down to about 16 ft but using dual band you can get to centimeters and long term measurements in the millimeter level.

     
    Last edited: Aug 14, 2019 at 12:58 AM
  4. Mans A

    Thread Starter New Member

    Aug 13, 2019
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    @jpanhalt How it can increase accuracy? As you can see from the image, both GPS chips are the same, so they can not capture different things.

    @Wolframore : As far as I know the old version of UBlox chips can only wok on one frequency. So this board can not implement two-band frequency GPS

    Any other idea?
     
  5. jpanhalt

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    The fact that they look the same doesn't mean they operate at the same frequency nor that the data processing algorithms are the same. Microprocessors/microcontrollers are very versatile.
     
  6. Wolframore

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    Jan 21, 2019
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    The datasheet for that ublox receiver says it's L1 but all satellites transmit L1 and L2. There are more frequencies being added for ionoshperic correction. There would be almost no benefit except redundancy otherwise if it isn't receiving L2.
     
  7. Mans A

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    Aug 13, 2019
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    Do you have any idea, what type of signal processing they may use to improve accuracy?

    Apparently, the GPS chips only work on L1 and not any other frequency.
     
  8. jpanhalt

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    Jan 18, 2008
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    Please provide a citation to support that fact. Simply put, if "GPS chips" can only receive L1, then why is L2 (and L5) even transmitted?
     
  9. Mans A

    Thread Starter New Member

    Aug 13, 2019
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    I mean the GPS chip used on that board which is a ublox M6 (https://www.u-blox.com/sites/defaul...ts/NEO-6_ProductSummary_(GPS.G6-HW-09003).pdf) only receive L1.

    So why they used two L1 GPS receiver to add accuracy? and how they are able to achieve this?
     
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