# Upper Bounds for the Capacity for Severely Fading MIMO Channels under a Scale Mixture Assumption

^{1}

^{2}

## Abstract

**:**

## 1. Introduction

#### 1.1. MIMO Channels and Capacity

#### 1.2. Scale Mixture of (Complex) Matrix Variate Normals and the Resulting Wishart

#### 1.3. Main Contribution of this Paper

## 2. Eigenvalue Pdfs and an Upper Bound

## 3. Capacity for the Case $\mathbf{p}=\mathbf{2}$

#### 3.1. Approximation for Case 1 and Case 2

#### 3.2. Exact Expression for Case 2

## 4. Conclusions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## Abbreviations

MIMO | multiple-input-multiple-output |

LOS | line-of-sight |

CN | complex matrix variate normal |

SMCN | scale mixture of complex matrix variate normal |

SMCW | scale mixture of complex Wishart |

probability density function |

## Appendix A

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Ferreira, J.T.
Upper Bounds for the Capacity for Severely Fading MIMO Channels under a Scale Mixture Assumption. *Entropy* **2021**, *23*, 845.
https://doi.org/10.3390/e23070845

**AMA Style**

Ferreira JT.
Upper Bounds for the Capacity for Severely Fading MIMO Channels under a Scale Mixture Assumption. *Entropy*. 2021; 23(7):845.
https://doi.org/10.3390/e23070845

**Chicago/Turabian Style**

Ferreira, Johannes T.
2021. "Upper Bounds for the Capacity for Severely Fading MIMO Channels under a Scale Mixture Assumption" *Entropy* 23, no. 7: 845.
https://doi.org/10.3390/e23070845