How to add cyclic prefix in ofdm in matlab

1. How to add cyclic prefix in OFDM in Matlab Simulink?
2. Why do we add cyclic prefix in OFDM?
3. How to remove cyclic prefix in OFDM matlab?
4. How is cyclic prefix calculated?

How to add cyclic prefix in OFDM in Matlab Simulink?

Step 4 of 5 in OFDM Modulation Using MATLAB

To be effective for equalization the cyclic prefix (CP) length must equal or exceed the channel length. Define variables for QAM and OFDM processing. Generate symbols, QAM-modulate, OFDM-modulate, and then add a CP to the signal.

Why do we add cyclic prefix in OFDM?

Cyclic prefix is inserted to avoid intersymbol interference due to the multipath channel. In practice, CP-OFDM modulator is implemented via the computationally efficient fast Fourier transform (FFT).

How to remove cyclic prefix in OFDM matlab?

At the receiver, we are only interested in the middle section of the lin_scp_h which is the channel output. The first block in the OFDM receiver removes the additional symbols from the front and back of the channel output. The resultant vector is the received symbol r after the removal of cyclic prefix in the receiver.

How is cyclic prefix calculated?

Therefore, the number of samples allocated for cyclic prefix can be calculated as Ncp=Tcp*N/T, where N is the FFT/IFFT length, T is the IFFT/FFT period and Tcp is the duration of cyclic prefix.