# What is SNR in OFDM?

## 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.

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