TY - JOUR
T1 - Covert Communication in the Presence of an Uninformed Jammer
AU - Sobers, Tamara V.
AU - Bash, Boulat A.
AU - Guha, Saikat
AU - Towsley, Don
AU - Goeckel, Dennis
N1 - Funding Information:
This work was supported in part by the National Science Foundation under Grant ECCS-1309573 and Grant CNS-1564067 and in part by DARPA under Contract HR0011-16-C-0111.
Publisher Copyright:
© 2002-2012 IEEE.
PY - 2017/9
Y1 - 2017/9
N2 - Recent work has established that when transmitter Alice wishes to communicate reliably to recipient Bob without detection by warden Willie, with additive white Gaussian noise (AWGN) channels between all parties, communication is limited to O(√n) bits in n channel uses. However, this assumes that Willie has an accurate statistical characterization of the channel. When Willie has uncertainty about such and his receiver is limited to a threshold test on the received power, Alice can transmit covertly with a power that does not decrease with n, thus conveying O(n) bits covertly and reliably in n uses of an AWGN channel. Here, we consider covert communication of O(n) bits in n channel uses while generalizing the environment and removing any restrictions on Willie's receiver. We assume that an uninformed "jammer" is present to help Alice, and we consider AWGN and block fading channels. In some scenarios, Willie's optimal detector is a threshold test on the received power. When the channel between the jammer and Willie has multiple fading blocks per codeword, a threshold test on the received power is not optimal. However, we establish that Alice can remain covert with a transmit power that does not decrease with n even when Willie employs an optimal detector.
AB - Recent work has established that when transmitter Alice wishes to communicate reliably to recipient Bob without detection by warden Willie, with additive white Gaussian noise (AWGN) channels between all parties, communication is limited to O(√n) bits in n channel uses. However, this assumes that Willie has an accurate statistical characterization of the channel. When Willie has uncertainty about such and his receiver is limited to a threshold test on the received power, Alice can transmit covertly with a power that does not decrease with n, thus conveying O(n) bits covertly and reliably in n uses of an AWGN channel. Here, we consider covert communication of O(n) bits in n channel uses while generalizing the environment and removing any restrictions on Willie's receiver. We assume that an uninformed "jammer" is present to help Alice, and we consider AWGN and block fading channels. In some scenarios, Willie's optimal detector is a threshold test on the received power. When the channel between the jammer and Willie has multiple fading blocks per codeword, a threshold test on the received power is not optimal. However, we establish that Alice can remain covert with a transmit power that does not decrease with n even when Willie employs an optimal detector.
KW - Low probability of detection communication
KW - physical layer security
KW - wireless covert communication
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U2 - 10.1109/TWC.2017.2720736
DO - 10.1109/TWC.2017.2720736
M3 - Article
AN - SCOPUS:85021937296
SN - 1536-1276
VL - 16
SP - 6193
EP - 6206
JO - IEEE Transactions on Wireless Communications
JF - IEEE Transactions on Wireless Communications
IS - 9
M1 - 7964713
ER -