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How to config DPD on AD9375?

Thread Summary

The user is experiencing issues with DPD performance on a custom board using AD9375 with a GaN PA, where the system with DPD enabled runs slower and has higher error rates compared to without DPD. The DPD and CLGC configurations appear correct, but the CLGC error status indicates it is disabled due to `allowTx1AttenUpdates` and `allowTx2AttenUpdates` being set incorrectly. The user is advised to ensure these parameters are enabled and to measure EVM and Tx output power to diagnose the issue further.
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Hi,

I use default DPDconfig to configure DPD on my custom board:

static mykonosDpdConfig_t dpdConfig =
{
    10,              /* 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,           /* 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)*/
};

My system have multi mode BPSK, QPSK, QUAM16,QUAM64 with bandwidth 5MHz, 10MHz, 20Mhz. 

I have feedback Tx2 signal into ORX2 with power -24dbm and configure dpd follow ug992. But i don't see any different between have setup DPD and no have DPD.

Here is status that I read using MYKONOS_getDpdStatus:

 dpdStatus.dpdErrorStatus = 0,

dpdStatus.dpdExtPathDelay = 0x73B ,

dpdStatus.dpdIterCount = 0,

dpdStatus.dpdMaxAdaptation = 0,

dpdStatus.dpdModelErrorPercent = 1000,

dpdStatus.dpdTrackCount = 0

Can you suggest for me how to solve? Thanks. This is my output from tx:

Edit Notes

dpdStatus.dpdErrorStatus = 0, dpdStatus.dpdExtPathDelay = 0x73B , dpdStatus.dpdIterCount = 0, dpdStatus.dpdMaxAdaptation = 0, dpdStatus.dpdModelErrorPercent = 1000, dpdStatus.dpdTrackCount = 0
[edited by: sonminh at 2:00 AM (GMT 0) on 24 Apr 2020]

Thread Notes