Data transferring plays a significant role in mobile application. This is largely affected by eavesdropping during the transmission, when the data is not encrypted. In this paper, we propose a secure communication channel among devices based on similar audio patterns. Features of ambient audio are used to generate small information between the devices. We explore a common audio-fingerprinting approach and account the noise in the derived fingerprints by applying error correcting codes. In secure data transfer in ambient audio, the sender device will send audio signals via its speaker and the receiver device uses microphone to receive the signals and decode the data from the sound wave. Phase key shifting scheme is used for data encryption and decryption. PSK is a digital modulation scheme that conveys data by changing, or modulating, the phase of a reference signal. Android based mobile system is used as a sender and receiver to demonstrate the concept. This kind of work can be used for short range communication without using a network like wifi, Bluetooth, etc. These schemes are useful in mobile applications like private information sharing, payment authentication, Near Field communication (NFC), etc.
