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arXiv · 1103.4406

Interference Alignment with Partially Coordinated Transmit Precoding

Aimal Khan Yousafzai·Mohammad Reza Nakhai
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Abstract

In this paper, we introduce an efficient interference alignment (IA) algorithm exploiting partially coordinated transmit precoding to improve the number of concurrent interference-free transmissions, i.e., the multiplexing gain, in multicell downlink. The proposed coordination model is such that each base-station simultaneously transmits to two users and each user is served by two base-stations. First, we show in a K-user system operating at the information theoretic upper bound of degrees of freedom (DOF), the generic IA is proper when $K \leq 3$, whereas the proposed partially coordinated IA is proper when $K \leq 5$. Then, we derive a non-iterative, i.e., one shot, IA algorithm for the proposed scheme when $K \leq 5$. We show that for a given latency, the backhaul data rate requirement of the proposed method grows linearly with K. Monte-Carlo simulation results show that the proposed one-shot algorithm offers higher system throughput than the iterative IA at practical SNR levels.

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Aimal Khan Yousafzai, Mohammad Reza Nakhai. 2011-03-22. Interference Alignment with Partially Coordinated Transmit Precoding. https://arxiv.org/abs/1103.4406

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