Abstract
The multi-input single-output (MISO) Gaussian wiretap channel
with delayed channel state information (CSI) available at the transmitter and at the eavesdropper is investigated. This scenario may
occur when the legitimate receiver sends its channel state to the
transmitter via a delayed feedback link which can be also overheard
by an eavesdropper. We show that delayed CSI, even completely
outdated, offers the opportunity to ensure the secrecy. Namely, by
aligning the artificial noise at the legitimate receiver, a secrecy degrees of freedom (SDoF) of 1/2 can be achieved. It turns out that
the result is irrelevant to whether the transmitter knows the legitimate channel or the eavesdropper channel with a delay and both
cases yield the equivalent opportunity. The artificial noise scheme
can be further extended to the case of broadcast channel with two
confidential messages.
with delayed channel state information (CSI) available at the transmitter and at the eavesdropper is investigated. This scenario may
occur when the legitimate receiver sends its channel state to the
transmitter via a delayed feedback link which can be also overheard
by an eavesdropper. We show that delayed CSI, even completely
outdated, offers the opportunity to ensure the secrecy. Namely, by
aligning the artificial noise at the legitimate receiver, a secrecy degrees of freedom (SDoF) of 1/2 can be achieved. It turns out that
the result is irrelevant to whether the transmitter knows the legitimate channel or the eavesdropper channel with a delay and both
cases yield the equivalent opportunity. The artificial noise scheme
can be further extended to the case of broadcast channel with two
confidential messages.
| Original language | English |
|---|---|
| Pages | 636-640 |
| DOIs | |
| State | Published - 2011 |