A digitized real voice signal is converted via complex filtering into a complex signal that is subjected to sampling rate reduction, the bandwidth of the respective complex filter corresponding to the sampling rate. The complex signal is encrypted using AES in CTR mode(stream transformation) and modulated in QPSK. There has to be be coding in LDPC and the performance of AES should be analysed in AWGN and multi-path fading channel.
The exact reverse process should follow for decryption and the original signal should be retreived.
BER analysis for AES-coded, AES-uncoded, plain-coded and plain-uncoded should be provided for AWGN and wireless channel.
Performance improvement has to be shown in the results.