# Multi-user Communication in Difficult Interference

## TL;DR

This paper investigates the impact of difficult co-channel interference on wireless communication, highlighting the vulnerability of M-QAM schemes and proposing M-PAM as a mitigation approach for such challenging interference conditions.

## Contribution

The paper demonstrates that M-PAM modulation can effectively mitigate difficult co-channel interference, offering a new approach to improve wireless link reliability under severe interference.

## Key findings

- M-QAM schemes are highly vulnerable to difficult CCI.
- M-PAM provides a promising mitigation method for difficult CCI.
- Single-dimensional modulation schemes can enhance interference robustness.

## Abstract

The co-channel interference (CCI) is one of the major impairments in wireless communication. CCI typically reduces the reliability of wireless communication links, but the difficult CCI which is no more or less strong to the desired signals destroys wireless links despite having myriad of CCI mitigation methods. It is shown in this paper that M-QAM (Quadrature Amplitude Modulation) or similar modulation schemes which modulate information both in in-phase and quadrature-phase are particularly vulnerable to difficult CCI. Despite well-known shortcomings, it is shown in this paper that M-PAM or similar schemes that use a single dimension for modulation provides an important mean for difficult CCI mitigation.