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If the OP is referring to the sampling frequency of the time domain waveform in the OFDM transmitter (after the IFFT), then these relationships will not always hold. … There are many practical reasons in an OFDM implementation to have a higher sampling frequency than the OFDM bandwidth. …

For the case of OFDM, we are actually converting the waveform into independent channels of significantly longer duration, thus solving this issue. … The cyclic prefix allows a guard interval to eliminate the intersymbol interference from a previous OFDM symbol. …

ICI vs Frequency Offset for OFDM A simple frequency offset is referred to as Carrier Frequency Offset (CFO) and would create a static rotation for all the subcarriers in one OFDM symbol (the constellation … (from one subcarrier to the next within a single OFDM symbol) for the case of time delay offset. …

can reduce overhead given more bins in terms of how many bins are used for pilots and the time slots for the cyclic prefix compared to the symbol duration (with more bins of the same bin spacing, the OFDM … As insight into the power vs bandwidth trade consider the following chart published in EETimes showing symbol error rate vs EbNo for the different modulation choices that could be used for the OFDM subcarriers …

For further details, please refer to these posts: OFDM. Cyclic Prefix and ISI https://dsp.stackexchange.com/a/16052/21048 …

I have worked with OFDM but have not had the opportunity to work on DFT-Spread-OFDM (DFT-s-OFDM) specifically, so my answer is not from experience. … Bottom Line: I believe DFT-s-OFDM essentially sends single carrier modulations using the OFDM structure. …

(1) Yes, if the technology permits it for the power handling requirements of the design, the strategy is to filter as much as possible immediately at the front-end of the receiver prior to the LNA. Th …

output voltage proportional to the frequency of the input) to provide higher and higher accuracies of what the carrier is, which can ultimately be within the capture range of whatever you are using for OFDM … For example, this link provides a typical discriminator for OFDM: Carrier frequency offset (CFO) estimation using cyclic prefix And this link provides further details on carrier discrimination techniques …

The time duration of each encoded symbol is $1/\Delta F$ but the time duration used to transmit each symbol is extended by the CP. So both results are valid as far as time duration for each symbol, bu …

No, there would be no local attenuation over the 10MHz subcarriers at 1800 MHz of any significance if you exclude the multipath effects. The standard path loss equation holds and this would be a non-d …

The result of your plot is what you would see when you have timing offset error but no frequency error. Given that it is over-sampled you can confirm this by manually adjusting your decision point a f …

Hence for OFDM we can map data to these possible symbol locations in an FFT directly, and then to produce the equivalent time domain waveform we take the IFFT result of this to generate the waveform that … We see this in the block diagram for the transmitter using OFDM, where the data itself represents frequency once mapped to complex sub-carriers and converted to time using an IFFT (beyond the scope of …

Since the Cyclic Prefix (CP) is taken from the end of the exact same OFDM symbol, it is circularly invariant, up to the shift equal to the length of the circular prefix, such that the resulting DFTs for … (With an advance we circularly rotate through the same data, up to the CP length, with a delay we start using data from the next OFDM symbol). …

provides more detailed formulas as to the actual offsets but the following graphic should provide more intuitive insight into both Sampling Frequency Offset (SFO) and Sampling Time Offset (STO) on one OFDM …

I show the details for a complete OFDM transmitter chain at this post, and this other post provides additional related details. … Below is a graphic representing the spectrum of an example OFDM waveform at baseband. …