Secured Transmission using Software Defined Radio Technique

Due to the rapid changes in technology, there is a need for    advanced security during data communication. The design and implementation     of conventional radios are quite expensive for security purpose. Hence we are going for Software defined radio (SDR). SDR technology provides an efficient and comparatively inexpensive solution to this problem. Software Defined Radio is a radio which can   tune to any frequency band. SDR ultimately brings flexibility and inter-operability in communication. It requires minimal infrastructure and reduced the cost of hardware.  Here we are using SDR to transmit and receive the OFDM radio signal by employing different   frequencies and different modulation techniques like QPSK, QAM and FSK.  To provide more security, an alert message is sent to both the transmitter and receiver sections as soon as the hacker tries to hack into the system. After receiving the alert message, the frequency and modulation techniques are changed immediately and the process is continued. Here the programs are written in Embedded C and complied using Keil compiler. For front-end, Visual Basic is used.