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Optimal power allocation in block fading channels with confidential messages

Chorti, Arsenia, Papadaki, Katerina ORCID: 0000-0002-0755-1281 and Poor, H. Vincent (2015) Optimal power allocation in block fading channels with confidential messages. IEEE Transactions on Wireless Communications, 14 (9). pp. 752-757. ISSN 1536-1276

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Identification Number: 10.1109/TWC.2015.2424964


The optimal power allocation for block fading (BF) networks with confidential messages is investigated under an M-block delay and power constraint. First, we study networks without channel state information (CSI) feedback to the transmitter and demonstrate that the optimal power allocation is the equidistribution of the power budget, denoted as the “blind policy”. In blind scenarios secrecy can be achieved though receiver diversity; the probability of secrecy outage (PSO) is shown to decay exponentially with the the diversity order of the legitimate user. Then, we investigate networks with CSI feedback. For comparison purposes, we restate the acausal secure waterfilling algorithm with full CSI before moving to the causal feedback scenario. In the latter, an approximate “threshold policy” for the low SNR and an approximate “high power policy” for the high SNR regimes are derived. Furthermore, a novel universal transmission policy is proposed across all SNRs, denoted as the “blind horizon approximation” (BHA). Through numerical results, the BHA policy is shown to outperform both the threshold and high power policies when the legitimate user has an SNR advantage with respect to the eavesdropper, while it also compares well with the secure waterfilling policy.

Item Type: Article
Official URL:
Additional Information: ©2015 IEEE
Divisions: Management
Subjects: H Social Sciences > HD Industries. Land use. Labor > HD61 Risk Management
T Technology > T Technology (General)
T Technology > TK Electrical engineering. Electronics Nuclear engineering
Date Deposited: 03 Jun 2015 09:39
Last Modified: 05 Jun 2024 04:00

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