0
Fast Fourier Transform (FFT) is used in Orthogonal Frequency Division Multiplexing (OFDM) to efficiently convert data from the time domain to the frequency domain. This allows for the simultaneous transmission of multiple signals over different subcarriers, maximizing bandwidth efficiency and minimizing interference. FFT reduces the computational complexity of the required discrete Fourier transform, making it feasible for real-time applications. Overall, FFT is crucial for achieving the high data rates and robustness that characterize OFDM systems.
What else can I help you with?
What are there advantages and where are there used fft?
because they have a high speed compared to fft
What is 'ofdm'?
Orthogonal frequency-division multiplexing
What is OFDM training symbol?
Orthogonal frequency-division multiplexing (OFDM) is a method of encoding digital. Pilot signals and training symbols (preambles) may also be used for time.
C coding for cooley tukey fft algorithm?
hi.... for DIT fft algorithm, refer to this link, it has c-code for that. http://cnx.org/content/m12016/latest/
What is the frequency range used in wireless communication?
2.4GHz is used & OFDM
What is SISO-OFDM?
SISO-OFDM is an OFDM system with one transmit and one receive antenna.
What are there advantages and where are there used fft?
because they have a high speed compared to fft
What are there advantages and where are there used?
FFT reduces the computation since no. of complex multiplications required in FFT are N/2(log2N). FFT is used to compute discrete Fourier transform.
How do you plot frequency spectrum using fft function in MATLAB?
plot(abs(fft(vectorname)))the FFT function returns a complex vector thus when you plot it, you get a complex graph. If you plot the absolute value of the FFT array, you will get the magnitude of the FFT.
Need of fft?
FT is needed for spectrum analysis, FFT is fast FT meaning it is used to obtain spectrum of a signal quickly, the FFT algorithm inherently is fast algorithm than the conventional FT algorithm
What is the need of FFT?
There's no need for it.
How many sub channels does OFDM use for carrying data?
OFDM uses 48 subchannels for data and 4 are used as Pilot Carriers.
What is loss of orthogonality means in OFDM technology?
In OFDM, sub-carrier spacing is maintained in such a way that the maximum of one sub-carrier occurs at the minimum of the successive sub-carrier, a loss of orthogonality results if this pattern is not achieved in the sub-carriers of OFDM transmission. Loss of orthogonality is due to ISI, ICS, Frequency offset amongst the sub-carriers of OFDM.
How you eliminate inter symbol interference in ofdm?
Inter symbol interference (ISI) in OFDM systems can be minimized by using a cyclic prefix. This involves adding a copy of the end of each OFDM symbol to the beginning before transmission. The cyclic prefix helps to mitigate the effects of multipath fading and reduces ISI by allowing the receiver to separate the OFDM symbols with a guard interval.
What is 'ofdm'?
Orthogonal frequency-division multiplexing
Why FFT is faster than DFT?
FFT is faster than DFT because no. of complex multiplication in DFT is N^2 while in FFT no. of complex multiplications are N/2(log2N). for example if N=8 no. of complex multiplications required in DFT are 64. while no. of complex multiplications required in FFT are 12 thus reduces computation time.
Explain ICI in ofdm systems?
Multi Carrier systems like OFDM has the problem of Inter Carrier Interference(ICI), which results from the loss of Orthogonality between the sub carriers.This happens when the FFT is considered over duration where the subcarrier is non integer number of cycles, which would be the case when multipath is present and the guard time has amplitude is zero.This is reduced by use of cyclic prefix, where we transmit a copy the last part of the symbol followed by the symbol itself.This ensures Orthogonality over the FFT period in case of delayed multipath. yup...that's all from me. Regards Girish .V.V There are many methods to reduce ICI not only CP like Frequency domain equalization,Time domain windowing,Pulse shaping,Maximum likelihood estimation,Extended kalman filtering and ICI self cancellation.And any one have their own advantages. Naser
