Howtosignalprocessing
- What is the effect of cyclic prefix and zero padding in OFDM?
- What is benefit of cyclic prefix in OFDM?
- What is the purpose of zero padding?
- What is difference between normal and extended cyclic prefix?
What is the effect of cyclic prefix and zero padding in OFDM?
If an OFDM symbol is Zero padded instead of cyclic prefix, ISI due to adjacent symbol still gets eliminated, but it cannot be modeled using circular convolution. Circular convolution converts frequency selective multipath channel into flat fading channel.
What is benefit of cyclic prefix in OFDM?
The purpose of the cyclic prefix is to combat ISI and intra-symbol interference. The cyclic prefix is a guard time made up of a replica of the time-domain OFDM waveform. The basic premise is to replicate part of the back of the OFDM signal to the front to create the guard period, as shown in Figure 3.31.
What is the purpose of zero padding?
Zero padding enables you to obtain more accurate amplitude estimates of resolvable signal components. On the other hand, zero padding does not improve the spectral (frequency) resolution of the DFT. The resolution is determined by the number of samples and the sample rate.
What is difference between normal and extended cyclic prefix?
The normal CP length is designed to support propagation conditions with a delay spread up to 4.7 μs, while the extended CP is intended to support deployments where the delay spread is up to 16.7 μs.
