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  1. #1
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    Infineon's BGT24MTR11 "IF 1/f corner frequency" is limiting FSK modulation frequency?

    In this document: https://www.infineon.com/dgdl/Infine...39df108e75025b
    on the page 13 there is a parameter called "IF 1/f corner frequency" = 10 kHz (max 20kHz)
    Does it mean that FSK switching modulation would be limited by this value?

    In my old X-band design mixer output was directly fed to opamp circuit through RC low-pass filter witch much higher frequency, up to 100kHz. After "fast" amplifier there was sample and hold circuity which produced two waveforms. Making RC low pass cutoff too low certainly will distort received FSK waveform.

    Now looking at BGT24's typical corner frequency of 10kHz and feel it may be too low?
    For maximum of 20kHz switching frequency may be around 20kHz to maybe 30kHz giving maximum sampling rate of 10 to 15kHz?

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    Re: Infineon's BGT24MTR11 "IF 1/f corner frequency" is limiting FSK modulation freque

    1/f corner frequency is a specification of expectable IF amplifier noise spectrum. Consider degraded signal-to-noise ratio if the IF is considerably below the corner. There should be no problem in a typical FSK application.


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  3. #3
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    Re: Infineon's BGT24MTR11 "IF 1/f corner frequency" is limiting FSK modulation freque

    Oh, it is not cutoff frequency of IF amplifier, I made a wrong statement.
    Now it looks very promising, there no such limit for BGT24 at all. Although there may be some limits at higher IFs, maybe few hundreds of kHz, or even MHz



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    Re: Infineon's BGT24MTR11 "IF 1/f corner frequency" is limiting FSK modulation freque

    The datasheet states IF frequency range 0 - 10 MHZ. DC capability is essential for homodyne receiver topology.


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  5. #5
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    Re: Infineon's BGT24MTR11 "IF 1/f corner frequency" is limiting FSK modulation freque

    somehow did not see that for more than a year, my attention was not enough



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