# SNR Degradation due to Carrier Frequency Offset in OFDM based Amplify-and-Forward Relay Systems

## TL;DR

This paper analyzes how carrier frequency offset affects the signal-to-noise ratio in OFDM-based amplify-and-forward relay systems, revealing high sensitivity influenced by channel power and gain factors.

## Contribution

It derives an SNR expression for both single and multiple relay scenarios considering CFO, providing insights into system sensitivity and performance degradation.

## Key findings

- SNR is highly sensitive to CFO in OFDM relay systems
- Sensitivity depends on link channel power and gain factors
- Analytical expressions quantify SNR degradation due to CFO

## Abstract

In this letter, signal-to-noise ratio (SNR) performance is analyzed for orthogonal frequency division multiplexing (OFDM) based amplify-and-forward (AF) relay systems in the presence of carrier frequency offset (CFO) for fading channels. The SNR expression is derived under one-relay-node scenario, and is further extended to multiple-relay-node scenario. Analytical results show that the SNR is quite sensitive to CFO and the sensitivity of the SNR to CFO is mainly determined by the power of the corresponding link channel and gain factor.