# How is LTE sampling rate calculated?

## How is LTE sampling rate calculated?

Base Sampling Rate is based on System Bandwidth (BW) and is set as follows: System BW = 1.4 MHz, Base Sampling Rate = 1.92 MHz. System BW = 3 MHz, Base Sampling Rate = 3.84 MHz. System BW = 5 MHz, Base Sampling Rate = 7.68 MHz. System BW = 10 MHz, Base Sampling Rate = 15.36 MHz.

**Why subcarrier spacing is 15 kHz in LTE?**

The LTE OFDM subcarrier spacing equals 15 kHz for both downlink and uplink. The selection of the subcarrier spacing in an OFDM-based system needs to carefully balance overhead from the cyclic prefix against sensitivity to Doppler spread/shift and other types of frequency errors and inaccuracies.

### How is F ft size related to FFT size?

The F FT size defines the number of bins used for dividing the window into equal strips, or bins. Hence, a bin is a spectrum sample, and defines the frequency resolution of the window. For a 44100 sampling rate, we have a 22050 Hz band. With a 1024 FFT size, we divide this band into 512 bins. FR = 22050/1024 ≃ 21,53 Hz.

**What’s the baseband FFT size of LTE?**

– Signal Processing Stack Exchange what’s the baseband FFT size of LTE? In standard of 3GPP LTE physical layer (3GPP TS 36.211), the FFT size for baseband signal generation for both Dl and UL is 2048 and CP size is also determined. However there is a table in several resources said we have different FFT and CP size. E.g. How is it possible?

#### Which is better 65 536 or FFT size?

In AS, the FFT size can’t be superior to 65 536, in order to display the sonogram, which corresponds to a 0.67 Hz frequency resolution – which is very high. A way to increase this frequency resolution would be decreasing the sampling rate.

**What happens if window size is smaller than FFT size?**

If the window size is smaller than the FFT size, the missing number of 0s is interpolated with the samples to get the closest power of two. The zero-padding doesn’t increase the information of the input signal, but the number of calculated samples.