Contents
What is FFT size in 5G?
It is 66.7 µs (for 15 KHz), 33.3 (for 30 KHz), 16.7 (for 60 KHz), 8.33 (for 120 KHz), 4.17 (for 240 KHz) and so on. Other 5G NR physical layer parameters are mentioned in the table-2. Subcarrier spacing (KHz) 15.
How to calculate LTE sampling frequency?
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.
What is a 5G PRB?
A E-UTRA PRB (Physical Resource Block) is defined as consisting of 12 consecutive subcarriers for one slot (0.5 ms). A PRB is the smallest element of resource allocation assigned by the eNB scheduler.
How is subcarrier spacing calculated?
Subcarrier spacing is equal to the reciprocal of the symbol time. As a result of the longer symbol time, the subcarrier size and spacing decreases from 312.5 KHz to 78.125 KHz. The narrow subcarrier spacing allows better equalization and therefore enhanced channel robustness.
How to calculate FFT size for 15 MHz?
A = 160 x (FFT size for 15 Mhz/FFT size for 20 Mhz) = 160 x (1536/2048) = 120 B = 144 x (FFT size for 15 Mhz/FFT size for 20 Mhz) = 144 x (1536/2048) = 108 C = 2048 x (FFT size for 15 Mhz/FFT size for 20 Mhz) = 2048 x (1536/2048) = 1536 10 Mhz BW Case :
What is minimum sampling frequency for 20Mhz LTE?
“For a 20MHz LTE system, the used Bandwidth for 1200SCs is 18MHz which means that minimum fs (sampling frequency) must be >= 36Mhz.” No, the 18MHz is the bandwidth of a complex signal (spectrum is not symmetrical).
How is the LTE signal sampled in time domain?
LTE signal is sampled at 30.72 MHz in time domain. As we use complex baseband signal, is means your whole system bandwidth might be 30.72 MHz exactly. As we produce time domain signal with help of iFFT, one may think signal frequency composition is defined by iFFT frequency inputs.
What kind of cheatsheet do you need for LTE PHY?
Followings would be a quick cheatsheet if you are DSP engineer or FPGA engineer working in LTE PHY. Let’s get into further details for some of the important parameters.