# A nonlinear approach to interference alignment

@article{Razaghi2011ANA, title={A nonlinear approach to interference alignment}, author={Peyman Razaghi and G. Caire}, journal={2011 IEEE International Symposium on Information Theory Proceedings}, year={2011}, pages={2741-2745} }

Cadambe and Jafar (CJ) alignment strategy for the K-user scalar frequency-selective fading Gaussian channel, with encoding over blocks of 2n+1 random channel coefficients (subcarriers) is considered. The linear zero-forcing (LZF) strategy is compared with a novel approach based on lattice alignment and lattice decoding (LD). Despite both LZF and LD achieve the same degrees of freedom, it is shown that LD can achieve very significant improvements in terms of error rates at practical SNRs with…

## 8 Citations

### A comparison of decoding techniques for Interference Alignment

- Computer Science2012 5th International Symposium on Communications, Control and Signal Processing
- 2012

This paper investigates the performance of the standard linear zero-forcing receiver, of linear integer forcing receivers, and of (non-linear) joint decoding implemented by lattice decoding with MMSE generalized decision feedback preprocessing and shows that the latter provides a significant improvement in terms of uncoded symbol error rate, averaged over the fading channel statistics.

### Interference alignment with diversity for the 2 × 2 X network with four antennas

- Computer Science2013 IEEE Global Communications Conference (GLOBECOM)
- 2013

This paper proves that the proposed LJJ scheme achieves the maximum possible sum DoF of 16/3 and also proves that, using any fixed finite constellation with appropriate rotation at each Tx, the proposed scheme achieves a diversity gain of at least four.

### Interference Alignment With Diversity for the 2 $\,\times\,$ 2 X-Network With Four Antennas

- Computer ScienceIEEE Transactions on Information Theory
- 2014

This paper proves that the proposed LJJ scheme achieves the maximum possible sum DoF of 16/3 and also proves that, using any fixed finite constellation with appropriate rotation at each Tx, the proposed scheme achieves a diversity gain of at least four.

### Combining interference alignment and Alamouti codes for the 3-user MIMO interference channel

- Computer Science, Business2013 IEEE Wireless Communications and Networking Conference (WCNC)
- 2013

A scheme is proposed that combines the interference-cancellation capability of Alamouti codes with the subspace-overlapping property of interference alignment to achieve a sum-rate of three symbols/channel use and significantly improves the bit-error rate performance compared to zero-forcing techniques.

### Interference alignment with diversity for the 2 × 2 X-Network with three antennas

- Computer Science, Business2014 IEEE International Symposium on Information Theory
- 2014

A new STBC for a three transmit antenna single user MIMO system and the LJJ scheme, which is extended to the 2×2 X-Network with three antennas at each node, achieves the maximum possible sum DoF of 4.

### Semi-blind interference alignment over correlated wireless channels

- Computer Science2014 IEEE Radio and Wireless Symposium (RWS)
- 2014

This paper mathematically analyze the impact of channel correlation and numerically show that S-BIA is more robust against the channel correlation than ordinary multiple-input multiple-output (MIMO) systems.

### Analysis of lattice codes for the many-to-one interference channel

- Computer Science2012 IEEE Information Theory Workshop
- 2012

This paper considers the case of joint maximum-likelihood decoding of the desired signal and the sum of interfering signals, derives the union bound for the error probability in terms of the theta series of these lattices, and shows that it is related to the flatness factor.

### Designing an overlay hybrid cognitive radio including channel estimation issues

- Physics
- 2014

La radio intelligente (RI) a ete proposee pour ameliorer l’utilisation du spectre radiofrequence. Pour cela, il s’agit de donner un acces opportuniste aux utilisateurs non licencies (nommes…

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