EVM: Error vector magnitude vector magnitude error

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EVM: Error vector magnitude vector magnitude error [Copy link]

EVM: Error vector magnitude
vector error

EVM is one of the most important indicators in the field of digital communication. It is affected by the following 7 aspects.
1. IQ branch gain imbalance. Assume the gain difference is, in dB
. 2. The local oscillator phase shift in the quadrature modulator is inaccurate, and the error is radians.
3. Carrier leakage, expressed in dBc. It is numerically equal to the ratio of the average signal power to the leaked carrier power.
4.
The influence of local oscillator phase noise. Use a random process (t) to represent the local oscillator phase noise
. 5. The amplitude-frequency characteristic of the channel filter is not ideal. Generally, the intermediate frequency sound table has a greater impact.
6. The phase-frequency characteristic of the channel filter is not ideal. Generally, the intermediate frequency sound table has a greater impact
. 7. The nonlinear distortion of the channel is generally more serious in the nonlinearity of the power amplifier.
The total EVM is the square root of the sum of the squares of the above seven items. It is a general independent error processing method.