Decentralized Power Control for Slotted Spread Spectrum Aloha with Successive Interference Cancellation

TL;DR

This paper analyzes decentralized power control in slotted spread spectrum Aloha with SIC, deriving optimal power distributions for consistent SNR across users under perfect and imperfect cancellation.

Contribution

It introduces an analytical framework for power distribution design in decentralized SIC-based Aloha systems, ensuring uniform SNR among users.

Findings

Derived an expression for expected interference power.

Identified power distributions achieving constant SNR.

Analyzed effects of imperfect interference cancellation.

Abstract

In this paper, we study slotted Spread Spectrum Aloha with Successive Interference Cancellation at the receiver over a Gaussian channel. We consider a decentralized power control setting in which each user chooses its transmit power independently at random according to a power distribution with continuous support. In this setting, we derive an analytical expression for the expected interference power experienced by a user. This allows us to derive analytically the power distribution that, during the Successive Interference Cancellation process leads to a constant signal to noise plus interference ratio for all users. We consider both perfect and imperfect interference cancellation.