# Antijamming Schemes for the Generalized MIMO Y Channel

## TL;DR

This paper introduces two new methods to protect MIMO Y channel communication from jamming attacks using signal space alignment.

## Contribution

The paper proposes two novel antijamming strategies for SSA in MIMO Y channels.

## Key findings

- The first scheme eliminates jamming by projecting signals into the null space of precoding vectors.
- The second scheme reduces jamming by subtracting an estimated interference signal.
- Simulations show the effectiveness of both strategies in various channel setups.

## Abstract

Signal space alignment (SSA) is a promising technique for interference management in wireless networks. However, despite the excellent work done on SSA, its robustness against jamming attacks has not been considered in the literature. In this paper, we propose two antijamming strategies for the SSA scheme applied in the multiple-input–multiple-output (MIMO) Y channel. The first scheme involves projecting the jamming signal into the null space of each source’s precoding vectors, effectively eliminating it entirely. The second scheme removes interference originating from the jammer by subtracting the disturbance estimate from the incoming signal. The estimate is derived on the basis of the criterion of minimizing the received signal energy. The block error rate (BLER) performance of the proposed strategies in various channel configurations is verified by link level simulations and is presented to show the efficiency in mitigating jamming signals within the SSA-based MIMO Y channel.