• State TI Thinks Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 2 answers
  • Subscribers 31 subscribers
  • Views 763 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

AWR1642: IIP2 and its impact

Adam Yao94020
Genius 10910 points
Part Number: AWR1642

Hi champion,
  I see in AWR1642 datasheet, the in-band IIP2 is 20dBm, and the out-band IIP2 is 35dBm. Could you help to explain what is the meaning of in-band IIP2 and out-band IIP2? And what is the impact of IIP2 to system?

Thanks,
Adam

  • 0
    TI__Guru*** 148804 points
    Hi,

    We need to check with the characterization team

    thank you
    Cesar
  • 0
    TI__Mastermind 30545 points
    Hello Adam,

    The IIP2 is basically the point where the power of the second order IM distortion intercepts the with the power of the fundamental frequency due to nonlinearity, i.e. the 0dBc point of the second order IM distortion products.

    An in-band IIP2 is within the IF band and out-band IIP2 is outside of the IF band (in the case of the datasheet this is 10kHz). The in-band second order distortion is seen by the entire RX system including the ADC since it is withing the IF band, where as the out-band is only seen by the LNA and the mixer. So, with out-band IIP2 it is the distortion products that end up within the IF band and are seen by the ADC that we need to worry about. These tones in the frequency spectrum can show up as undesirable objects in the FFT.

    Regards,

    Adrian
  • 0 in reply to aozer
    Prodigy 80 points
    Hello, can you give a calculation example

    for instance, there are 2 IF frequency(means 2 objects), one is 1MHZ -45dBm, another is 1.2MHZ -49dBm. then what frequency is the IM noise? and what is the power level?
  • 0 in reply to Fucai Yan15
    TI__Mastermind 30545 points
    Hello Fucai,

    The slope of the IM2 is going to be twice that of the input power. So, since the intercept point is at 20dBm for in band, we can expect the IM2 decrease twice as fast as the input from this value meaning that for an input power of -45dBm the IM2 would be equal to 2*(-45-20) = -130dBm. You can do the same for -49dBm.

    Regards,

    Adrian