Vulnerabilities of Massive MIMO Systems to Pilot Contamination Attacks

Abstract

We consider a single-cell massive MIMO system in which a base station (BS) with a large number of antennas transmits simultaneously to several single-antenna users in the presence of an attacker.The BS acquires the channel state information (CSI) based on uplink pilot transmissions. In this work, we demonstrate the vulnerability of CSI estimation phase to malicious attacks. For that purpose, we study two attack models. In the first model, the attacker aims at minimizing the sum-rate of downlink transmissions by contaminating the uplink pilots. In the second model, the attacker exploits its in-band full-duplex capabilities to generate jamming signals in both the CSI estimation and data transmission phases. We study these attacks under two downlink power allocation strategies when the attacker knows and does not know the locations of the BS and users. The formulated problems are solved using stochastic optimization, Lagrangian minimization, and game-theoretic methods. A closed-form solution for a special case of the problem is obtained. Furthermore, we analyze the achievable individual secrecy rates under a pilot contamination attack, and provide an upper bound on these rates. Our results indicate that the proposed attacks degrade the throughput of a massive MIMO system by more than 50%. Index termsMassive MIMO, pilot contamination, physical layer security, active attack, stochastic optimization.

Physical Layer Security Issues in Massive MIMO and GNSS

“…Jammers are able to send any signals. For example, in [8], the jammers are assumed to know the pilot signals and the vulnerabilities of massive MIMO are analyzed when the jammers send the pilot signals to the BS during training phase. In [9][10][11], some countermeasure techniques are proposed when the jammers send the pilot signals as the attack signals.…”

Frequency synchronisation for massive MIMO: a survey

“…One of the main advantages of massive MIMO is that the existence of a large number of antennas makes this system more robust to interference and intentional jamming compared to conventional communication systems employing a small number of antennas [9]. However, massive MIMO is vulnerable to this jamming when considering the pilot phase [10]. Therefore, for massive MIMO to become a reality, these hardware imperfections should be overcome.…”

Detection of Pilot Contamination Attack for Frequency Selective Channels

“…Consequently, a precoder design steers partial beam towards active Eve [32]. Furthermore, as a result of PCA, the correlation between the channel estimates at legitimate nodes significantly decreases, which causes higher key disagreement between legitimate nodes [33], [34]. The PCA detection is vital to take proper measures to secure physical layer communication from eavesdropping.…”