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What's the linear range of the power amplifiers on Sora board? RRS feed

  • Question

  • Hi, I wanna to check the linear range of the power amplifiers on Soar board, is there any way to get this range? Furthermore, if I set rxpa as 0x3000 and rxgain as 0x3E00, will the power amplifiers work in their linear range? Thanks.
    Tuesday, March 6, 2012 5:12 AM

Answers

  • According to our experience in XCVR2450 or V3 radio, the RX PA (dut rxpa) and RX VGA (dut rxgain) are almost always working in their linear rang. The TX PA could be out of its linear range when the gain setting (dut txgain) is too high. To guarantee the radio channel performance, it's not suggested to use txgain higher than 0x1300.

    -Jiansong

    Saturday, March 10, 2012 4:00 PM

All replies

  • According to our experience in XCVR2450 or V3 radio, the RX PA (dut rxpa) and RX VGA (dut rxgain) are almost always working in their linear rang. The TX PA could be out of its linear range when the gain setting (dut txgain) is too high. To guarantee the radio channel performance, it's not suggested to use txgain higher than 0x1300.

    -Jiansong

    Saturday, March 10, 2012 4:00 PM
  • In our Sora, the rxpa, rxgain and txgain parameters may work well some time, but may not work the next time. I'm confused and don't know why. Could you give me an advice?

    Monday, March 12, 2012 8:42 AM
  • hello, jiansong,

    your reply has a problem. The proper txgain shouldn't been set higher than 0x1e00.

    Wednesday, March 14, 2012 3:29 AM
  • @ychm,

    To set rxgain to 0x3e00 is way too high. Note that the rxgain controls the VGA in XCVR2450, which is not low noise. So the setting will raise the noise floor too high.

    - Kun

    Thursday, March 22, 2012 8:54 AM
  • Hi Albert,

    Thank you for your reply. Txgain of 0x1e00 could degrade performce in some extreme case, e.g. 64QAM. According to my experience, txgain value no more than 0x1300 is safe.

    -Jiansong

    Monday, March 26, 2012 11:06 AM