Electronic Wallet with Acoustic Localization

Over the last few years digital wallets’ popularity has risen significantly and many users choose to leave their wallets at home in favor of E-wallets, allowing easy payment through a person’s cell phone. In this project we have developed a digital wallet app that utilizes sound waves to perform acoustic localization. The app measures the distance between the customer and the cashier and allows payment only if the customer is within the desired range. The device measures the range by sending an acoustic signal; the second device responds with another signal upon hearing it and the ranger is calculated according to the time of propagation. In addition to the range measurement function, we have also developed a frequency-based communication system between the devices. Both systems rely on sound waves only. The motivation for an acoustic solution is accessibility - every cellular device has a sound system, also - an acoustic waves move 6 orders slower than electromagnetic waves, resulting in a much smaller effect of the time measurement precision on the range measurement. The innovation in this project is the usage of a set delay. The responding device waits before responding according to its own inner delay which varies with every activation of the app. This allows the first device to subtract the set delay from the propagation time instead of requiring the second device’s inner delay every time. During this project, we have successfully developed the app from scratch, while fitting all our requirements. Our app works in real-time and performs range measurement with the precision of 10 cm. The technology in this project is versatile and can be used for multiple applications so there are many ways for this project to advance.

e wallet applications

Electronic Wallet with Acoustic Localization