Performance analysis of encrypted structured random interleaver

The conventional interleaves of Turbo Code (TC) provides the required permutation to the information bits and achieves a near Shannon limit Bit Error Rate (BER) performance. A novel method of Encrypted Structured Random Inter-leaver (ESRI) provides encryption in addition to shuffling. The secret key of ESRI determines the shuffling pattern and allows only the authorized users to recover the correct information. Conventional interleavers provide a tradeoff between spread factor and dispersion. The objective of the proposed ESRI is to simultaneously provide a spreading factor larger than the random interleaver and dispersion larger than a deterministic interleaver required for better Bit Error Rate (BER) of TC. The results depict a superior performance of ESRI amongst various interleavers under investigation. Rate-
¹
/ TC deploying ESRI shows BER performance similar to conventional TC achieving a BER of 10
^-5
at 1.3 dB of Signal to Noise Ratio (SNR).