RE: ADRv9025 _EVM

Hi,

i am tested ADRV9029 at Band-1 and Band-2, at Band-1 Frequency EVM is degraded.

Radio Scripts_Vyapi_V2_002 Radio Scripts_Vyapi_V2_002
Frequency=2140MHz(Band-1) Frequency=875MHz(Band-5)
Input Section ACPR(dBc)@carrier center to measured BW Edge CCDF(dB)   Input Section ACPR(dBc)@carrier center to measured BW Edge CCDF(dB)
Applied Attenuation (dB) at Vyapi_V2_002 output Channel Power(dBm) vyapi_V2_002 EVM(dB) Lower side(dBc) (BW=10MHz) Upper Side(dBc) (BW=10MHz)   Applied Attenuation (dB) at Vyapi_V2_002 output Channel Power(dBm) vyapi_V2_002 EVM(dB) Lower side(dBc) (BW=10MHz) Upper Side(dBc) (BW=10MHz)
-15 -14.44 -39.28 -53.4 -53.3 10.98   -10 -4.71 -41.7 -54 -54.3 10.98
-14 -13.45 -39.15 -54.3 -54.5 10.94   -1 4.18 -41.63 -61.1 -61.1 10.91
-13 -12.45 -39.66 -55.1 -55.2 10.97   0 5.27 -41.62 -60.2 -61.3 10.94
-12 -11.46 -39.8 -55.8 -55.9 10.94            
-11 -10.51 -39.5 -56.5 -56.8 10.97            
-10 -9.57 -38.38 -57.5 -57.6 10.92  
-1 -0.64 -38.86 -62.2 -63 10.96
0 0.292 -39.3 -61.4 -63.4 10.97
  • +1
    •  Analog Employees 
    on Apr 21, 2021 8:50 AM

    Factors that can impact EVM are power supply and reference clock phase noise.

    Instead of applying attenuation , can you reduce the input DBFS of the signal from FPGA. Scale it in FPGA and check for EVM and ACLR.

    Since the EVM degradation seen is small., make sure you measure same at Transceiver output.

    The ACLR difference seen with attenuation change can be because of Analyzer settings. Try reducing the attenuator inside SA when you apply higher attenuation,