Changes between Version 19 and Version 20 of WARPLab/Examples/OFDM


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Timestamp:
Nov 2, 2015, 4:06:02 PM (8 years ago)
Author:
chunter
Comment:

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  • WARPLab/Examples/OFDM

    v19 v20  
    1051053. The "EVM and SNR" plot shows that EVM is small and has little dependence on OFDM symbol index or subcarrier index. Furthermore, the red line shows the effective SNR of the reception (calculated from the EVM values themselves).
    106106
    107 === CFO Recovery: Disable, Phase Error Recovery: Enabled, SFO Recovery: Enabled ===
     107=== CFO Recovery: Disabled, Phase Error Recovery: Enabled, SFO Recovery: Enabled ===
    108108
    109109||  [[Image(Cn_PEy_Sy_phaseError.png,width=400)]][[BR]]1. Phase Error Estimates and SFO Recovery Matrix  ||  [[Image(Cn_PEy_Sy_constellations.png,width=400)]] [[BR]]2. Rx Constellation  ||  [[Image(Cn_PEy_Sy_evm.png,width=400)]] [[BR]]3. Error Vector Magnitude (EVM)[[BR]] and effective SNR  ||
    … …  
    111111By disabling time-domain CFO correction, we have increased the burden on the phase error recovery system. In effect, the residual CFO to be corrected is now considerably larger. This can be observed in the "Phase Error Estimates" plot in the first figure above. The number of 2π wraps is considerably larger than the previous scenario where time-domain CFO correction was enabled. Ultimately, however, phase error recovery can only go so far. By the time the system is applying phase corrections in the frequency domain, ICI has already occurred. This can be observed in the "EVM and SNR" plots where the effective SNR is a couple of dB worse than the previous case.
    112112
    113 === CFO Recovery: Disable, Phase Error Recovery: Enabled, SFO Recovery: Enabled ===
     113=== CFO Recovery: Disabled, Phase Error Recovery: Enabled, SFO Recovery: Enabled ===
    114114
    115115||  [[Image(Cn_PEn_Sy_phaseError.png,width=400)]][[BR]]1. Phase Error Estimates and SFO Recovery Matrix  ||  [[Image(Cn_PEn_Sy_constellations.png,width=400)]] [[BR]]2. Rx Constellation  ||  [[Image(Cn_PEn_Sy_evm.png,width=400)]] [[BR]]3. Error Vector Magnitude (EVM)[[BR]] and effective SNR  ||
    116116
     117=== CFO Recovery: Enabled, Phase Error Recovery: Enabled, SFO Recovery: Disabled ===
    117118
     119||  [[Image(Cy_PEy_Sn_phaseError.png,width=400)]][[BR]]1. Phase Error Estimates and SFO Recovery Matrix  ||  [[Image(Cy_PEy_Sn_constellations.png,width=400)]] [[BR]]2. Rx Constellation  ||  [[Image(Cy_PEy_Sn_evm.png,width=400)]] [[BR]]3. Error Vector Magnitude (EVM)[[BR]] and effective SNR  ||
    118120
    119121== Limitations ==