| Popis: |
With the increasing threat of lawbreakers to public security, proactive eavesdropping and supervision begin to play an important role in the commercial and military fields. This paper proposes a proactive monitoring scheme for jamming first and then eavesdropping for suspicious communication in decode-and-forward (DF) relay network. After the suspicious user is jammed, in order to maintain a constant outage probability, it is forced to change the transmission rate of the suspicious users. By converting the relationship between the suspicious transmission rate and the jamming power, the expression of optimal suspicious communication rate that maximizes the average eavesdropping rate under certain limiting conditions is obtained; in that way, the expression of optimal jamming power is obtained. Comparing this optimal jamming scheme with passive eavesdropping and proactive eavesdropping under constant jamming power, both of the results of expression and simulation show that the average eavesdropping rate under this optimal scheme significantly outperforms the other two schemes. |
