I have V-OFDM system (Vector OFDM) where every symbol is organized as in below figure:
The black cirles are pilots and white circles are data. First, iFFT operation it taken per column, and then collecting data is taken row-wise resulting collected data as shown in the figure right. It means first eight samples are pilot and following 24 sample are data, then 8 samples are pilot and so on. Then adding CP --> channel --> noise -->received data
In the receiver side, After usual processing of removing CP -->reshaping --> FFT column wise. We get the received data equivalent into transmitted data in above figure left. Then extract the pilots which are in our case of size $(3,8)$.
Then, LS estimation is performed, by dividing the received pilot by original pilot to get the frequency-domain estimated channel.
I ask here, how can we interpolate the channel in this case ? if I get a frequency-domain estimated channel of size $(3,8)$, what's the process to interpolate it into size of my symbol ? I think it should be vector interpolation? how can I do it in that case?