2 research outputs found
LDPC coded transmissions over the Gaussian broadcast channel with confidential messages
We design and assess some practical low-density parity-check (LDPC) coded
transmission schemes for the Gaussian broadcast channel with confidential
messages (BCC). This channel model is different from the classical wiretap
channel model as the unauthorized receiver (Eve) must be able to decode some
part of the information. Hence, the reliability and security targets are
different from those of the wiretap channel. In order to design and assess
practical coding schemes, we use the error rate as a metric of the performance
achieved by the authorized receiver (Bob) and the unauthorized receiver (Eve).
We study the system feasibility, and show that two different levels of
protection against noise are required on the public and the secret messages.
This can be achieved in two ways: i) by using LDPC codes with unequal error
protection (UEP) of the transmitted information bits or ii) by using two
classical non-UEP LDPC codes with different rates. We compare these two
approaches and show that, for the considered examples, the solution exploiting
UEP LDPC codes is more efficient than that using non-UEP LDPC codes.Comment: 5 pages, 5 figures, to be presented at IEEE ICT 201