## What is SNR in OFDM?

The estimation of signal-to-noise ratio (SNR) is a major issue in wireless orthogonal frequency-division multiplexing (OFDM) system. The proposed scheme computes the circular correlation between the received signal and the comb-type pilot sequence to obtain the SNR.

**What is OFDM symbol duration?**

To complete the OFDM symbol, a 0.8 us duration Guard Interval (GI ) is then added to the beginning of the OFDM waveform. This produces a “single” OFDM symbol with a time duration of 4 us in length, (3.2 us + 0.8 us).

### What is OFDM spectrum?

In telecommunications, orthogonal frequency-division multiplexing (OFDM) is a type of digital transmission and a method of encoding digital data on multiple carrier frequencies. In OFDM, multiple closely spaced orthogonal subcarrier signals with overlapping spectra are transmitted to carry data in parallel.

**What is OFDM receiver?**

Orthogonal frequency-division multiplexing (OFDM) is a multi-carrier modulation system where data is transmitted as a combination of orthogonal narrowband signals known as subcarriers. However, OFDM is more robust to frequency selective fading and simplifies equalization at the receiver.

## How do I calculate OFDM bandwidth?

Thus the bandwidth of the OFDM baseband signal is N/2*delta_f,delta_f is the sub-carrier frequency spacing. The sub-carrier frequency spacing delta_f =1/Ts= 1/(Td * N), Ts is the OFDM symbol duration,Td is the sampling symbol duration and equal to the smapling time interval。 Thus Td=1/fs, fs is the DAC sampling rate.

**How is OFDM symbol duration calculated?**

The symbol duration is simply 1/subcarrier and hence 1/15000 = 66.66us.

### How many subcarriers are in OFDM?

52 subcarriers

A single OFDM symbol contains 52 subcarriers; 48 are data subcarriers and 4 are pilot subcarriers. The center, “DC” or “Null”, zero subcarrier is not used. All data subcarriers use the same modulation format within a given burst.

**How does OFDM provide high data rate?**

By transmitting a large number of separate carriers, each conveying a low data rate stream, OFDM can attain high data rates. By properly choosing the symbol duration and carrier spacing, efficient modulation and demodulation of the signal is possible.

## How much bandwidth is an OFDM?

Each OFDM channel consists of 128 to 2048 sub-carriers and can occupy bandwidths from 1.25 MHz to 20 MHz.

**What is OFDM symbol rate?**

OFDM can generate a new symbol (composed of 48 subcarriers) every 4 microseconds. Based on that, it’s possible to signal 250,000 symbol transitions every second on each of the subcarriers.