Extending INET Framework for Directional and Asymmetrical Wireless Communications

This paper reports our work on extending the Omnet INET Framework with a directional radio model, putting a special emphasis on the implementation of asymmetrical communications. We first analyze the original INET radio model, focusing on its design and components. Then we discuss the modifications that have been done to support directional communications. Our preliminary results show that the new model is flexible enough to allow the user to provide any antenna pattern shape, with only an additional reasonable computational cost.

💡 Research Summary

The paper presents an extension of the OMNeT++ INET framework that introduces a directional radio model with explicit support for asymmetrical communications. The authors begin by dissecting the original INET radio module, which treats propagation loss as a simple product of a distance‑based path‑loss function and a scalar antenna gain that is assumed to be identical for both transmission and reception. This design, while sufficient for omnidirectional scenarios, cannot represent realistic cases where antennas have direction‑dependent gain patterns, where beamforming is employed, or where the link characteristics differ in each direction.

To overcome these limitations, the authors redesign the radio stack into three principal components. The first component, AntennaPattern, abstracts an antenna’s gain as a function of elevation (θ) and azimuth (φ). Users may supply a mathematical expression, a lookup table, or an external file (CSV, XML) that defines the gain over the sphere. The class provides linear interpolation by default and allows higher‑resolution sampling when needed, making it possible to model a wide variety of antenna shapes such as cones, parabolic dishes, or arbitrary user‑defined patterns.

The second component, PropagationLoss, augments the classic distance‑based loss with the directional gains of both the transmitter and the receiver. The loss equation becomes
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