Rake Receiver Algorithm for Aerial Acoustic Communication of Smart Devices

Abstract

Aerial acoustic communication has attracted attention recently along with the growing market of smart devices. It is because acoustic modem can be easily implemented in smart devices by re-using the audio interfaces, i.e., internal speakers and microphones. In this thesis, a rake receiver algorithm upon a software-based demodulator of aerial acoustic communication is proposed. It is desirable to adopt a rake receiver algorithm in an chirp acoustic communication thanks to its wide bandwidth, as a rake receiver is used for in 3G Code Division Multiple Access (CDMA) mobile system. We first review an inaudible chirp-based modem architecture in [1]. Then, we propose a rake receiver algorithm which can be implemented in the aforementioned modem. The proposed rake receiver algorithm can enhance the success rate of signal reception. After that, we continue to enhance the algorithm to deal with a few erroneous cases. Through extensive experimentation we verify the algorithm performance in comparison with the demodulator in [1]. The result shows that the proposed algorithm can obtain an average gain of 58:9% in success rate of signal reception, and the maximum gain of 179% in certain device.