The effects of phase noise in COFDM
The reception of a COFDM signal is analyzed in this article taking the particular case that phase noise has been added to the signal. The distinguished errors found are : common phase error and inter-carrier interference. using a pair of weighting functions, the effects of this distortions is removed from the signal.
How is phase noise introduced
Phase noise is the random perturbation of the phase of the steady sinusoidal waveform and practically all oscillators are affected by this. The phase noise maybe introduced in the process of shifting the modulated signal up to RF in the transmitter, and also in the process of downshifting from RF to IF or baseband in the receiver. The phase-noise spectrum of local oscillators(frequency stabilised by PLL ) depends on the properties of the free-running oscillator, and also the components of the PLL . the phase noise
of all the LOs in the chain between the receiver and the modulator will be present in the receiver.
two types of phase-noise contribution
The two types are The “common” phase-error part and the The "thermal-noise-like" part.
For more details, refer this pdf:
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