Extending IoT Connectivity of Embedded Devices with M2M High-Speed Acoustic Data Transmission
Henrique Gonçalves Nogueira, Jorge Peña Queralta, Tommi Otsavaara and Tomi Westerlund
Connectivity is central to the development of new products and services for the Internet of Things (IoT). Over the past two decades, multiple solutions have emerged to provide connectivity to embedded devices and build the IoT as we know it today, from Wi-Fi and Bluetooth modules to the latest developments in low-power wide-area networks. Nonetheless, multiple products exist on the market with embedded processors that have no connectivity. We provide a solution for extending IoT connectivity to musical instruments equipped with pickup transducers through one-way acoustic data transmission. By exploiting existing hardware in a variety of musical instruments, such as electric or bass guitars, we provide a new communication interface that can be utilized to upgrade the firmware or modify the settings of these devices. This process is currently done with a wired connection. We present a system that allows users to send instructions or new firmware to musical instruments utilizing their smartphones through a wireless acoustic link. We have implemented the proposed solution, which is based on OFDM modulation, achieving transmissions speeds of one order of magnitude higher than the most widely used solution at the moment. Through extensive experiments, we analyze the performance of our system under different channel conditions and settings. In addition, we provide a strategy to cope with frequency offsets between emitter and transmitter.