How to work DPD on AD9375 with DPD parameters set by user

I have a question about how to set parameters and work DPD on AD9375 with parameters set .

I confirmed that DPD works on AD9375 with DPD default parameters.

but there is still room for improvement in terms of Adjacent Channel Leakage Radio (ACLR).

So, I tried to change DPD default parameters to custom DPD paramerters by using API function (MYKONOS_configDpd()) and evaluated ACLR. Conseqently, ACLR was unchaned, compared to ACLR with default DPD parameters. 

I'd like to know how to work DPD on AD9375 with custom DPD parameters.

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    •  Analog Employees 
    on Jul 17, 2019 6:59 AM in reply to yinaba
    static mykonosDpdConfig_t dpdConfig = 

        5,              /* 1/2^(damping + 8) fraction of power `forgotten' per sample (default: `1/8192' = 5, valid 0 to 15), 0 = infinite damping*/ 
        1,              /* number of weights to use for int8_cpx weights weights member of this structure (default = 1)*/ 
        2,              /* DPD model version: one of four different generalized polynomial models: 0 = same as R0 silicon, 1-3 are new and the best one depends on the PA (default: 2)*/ 
        1,              /* 1 = Update saved model whenever peak Tx digital RMS is within 1dB of historical peak Tx RMS*/ 
        20,             /* Determines how much weight the loaded prior model has on DPD modeling (Valid 0 - 32, default 20)*/ 
        0,              /* Default off = 0, 1=enables automatic outlier removal during DPD modeling */ 
        512,            /* Number of samples to capture (default: 512, valid 64-32768)*/ 
        4096,//4096,    /* threshold for sample in AM-AM plot outside of 1:1 line to be thrown out. (default: 50% = 8192/2, valid 8192 to 1)*/ 
        0,              /* 16th of an ORx sample (16=1sample), (default 0, valid -64 to 64)*/ 
        255,            /* Default 255 (-30dBFs=(20Log10(value/8192)), (valid range  1 to 8191)*/ 
        {{64,0},{0,0},{0,0}}/* DPD model error weighting (real/imag valid from -128 to 127)*/ 

    The above shows that you are configuring default values for DPD config.

    You can try tuning the full range for the custom parameters and verify whether that it impacts the ACLR.