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    What's axial ratio and polarization ratio rhcp is acceptable

    What's axial ratio and polarization ratio rhcp is acceptable?

    I'm working on a truncated corner patch at 2.4 GHz

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    What's axial ratio and polarization ratio rhcp is acceptable

    usually AR should be about 1dB for high performance systems and/or narrowband. In other cases an AR of 3dB might be acceptable (e.g. for very wide band operation and/or cheap systems where fidelity is not as important). using truncated patch you should be able to get AR near 0dB at the center frequency and varies very fast around it.


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    What's axial ratio and polarization ratio rhcp is acceptable

    Thank you for your help

    You answer me the firt question
    also I need to know the polarization ratio for
    predominantly RHCP |ER/EL| I saw that in
    https://www.edaboard.com/ftopic116274.html
    but i mn't really convinced

    regards



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    What's axial ratio and polarization ratio rhcp is acceptable

    you may consider the polarization ratio as the cross-polar component in linearly polarized antennas. The smaller they are the better. I didn't see anyone who mentions this one unless he is sending two channels on the same polarization and he cares a lot for the isolation between them.



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    What's axial ratio and polarization ratio rhcp is acceptable

    Right adel_48
    I've got good axial ratio, but the reflection coeficient s11 is bad, and central frecuency is 2.45.
    the axial ratio is 1.04 and the s11 in 2.4 GHz is -8.5 dB , Is the reflection coeficient s11 acceptable, isn´t it?

    Added after 1 minutes:

    I'm new this is my first design



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    What's axial ratio and polarization ratio rhcp is acceptable

    hi,

    the reflection being acceptable or not is really a matter of design. Usually for narrowband systems that are not size limited (such as your design). the S11 should be well below -10dB (~-15 : -20). Since you cannot guarantee getting the same results in the measurement.

    However, -10dB corresponds to 90% of the incident power is radiated, -8dB => 85% radiated, -3dB => 50% radiated. Thus, for me, as long as I can ensure that the high reflection won't affect the previous stages (e.g. drive the power amplifier out of its stability region) and I am not designing a low power system, I would accept -8dB and maybe even much worse. I will consider it a poor design but it can be used.

    best regards,
    Adel


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