# Transceiver Design for Ambient Backscatter Communication over Frequency-Selective Channels

## TL;DR

This paper proposes a novel transceiver design for ambient backscatter communication over frequency-selective channels, utilizing OFDM cyclic prefix to cancel interference and improve detection accuracy without disrupting existing systems.

## Contribution

It introduces an interference-free transceiver design using OFDM cyclic prefix for frequency-selective channels, enhancing detection and maintaining compatibility with current OFDM systems.

## Key findings

- Interference cancellation using cyclic prefix improves detection accuracy.
- The chi-square based detector with optimal threshold enhances system performance.
- Simulations confirm the effectiveness of the proposed design.

## Abstract

Existing studies about ambient backscatter communication mostly assume flat-fading channels. However, frequency-selective channels widely exist in many practical scenarios. Therefore, this paper investigates ambient backscatter communication systems over frequency-selective channels. In particular, we propose an interference-free transceiver design to facilitate signal detection at the reader. Our design utilizes the cyclic prefix (CP) of orthogonal frequency-division multiplexing (OFDM) source symbols, which can cancel the signal interference and thus enhance the detection accuracy at the reader. Meanwhile, our design leads to no interference on the existing OFDM communication systems. Next we suggest a chi-square based detector for the reader and derive the optimal detection threshold. Simulations are then provided to corroborate our proposed studies.