Transreceiving of encrypted medical image – a cognitive approach

Recently, there is an increasing demand for efficient and secure transreception of medical images in telemedicine applications. Though a fixed spectrum is allocated to each user, most of the time it remains unused by the concerned user. Cognitive Radio (CR) is a technology that utilizes the unused spectrum efficiently by adopting spectrum sensing concept. This paper proposes an efficient and secure transmission of medical images by adopting CR technology and image encryption technique. Firstly, the novel medical image encryption algorithm is proposed to encrypt the DICOM (Digital Imaging and Communications in Medicine) image effectively. Then, the spectrum sensing technique is carried out via Universal Software Radio Peripheral (USRP) to sense the unused frequency band to transmit the encrypted bio signal. The proposed encryption algorithm combines DNA (Deoxyribo Nucleic Acid) sequence operation and chaotic maps to successfully encrypt the DICOM image pixels. Experimental results are done and various analysis such as Unified Average Changing Intensity (UACI), Number of Pixel Changing Rate (NPCR), entropy estimation and chi-square tests are carried out to validate the sternness of the encryption algorithm.