Details

Autor(en) / Beteiligte

• Razaviyayn, Meisam
• Lyubeznik, Gennady
• Zhi-Quan Luo

Titel

On the Degrees of Freedom Achievable Through Interference Alignment in a MIMO Interference Channel

Ist Teil von

• IEEE transactions on signal processing, 2012-02, Vol.60 (2), p.812-821

Ort / Verlag

New York, NY: IEEE

Erscheinungsjahr

2012

Quelle

IEEE Electronic Library Online

Beschreibungen/Notizen

• Consider a K-user flat fading MIMO interference channel where the kth transmitter (or receiver) is equipped with M k (respectively N k ) antennas. If an exponential (in K) number of generic channel extensions are used either across time or frequency, Cadambe and Jafar [1] showed that the total achievable degrees of freedom (DoF) can be maximized via interference alignment, resulting in a total DoF that grows linearly with A even if M k and N k are bounded. In this work we consider the case where no channel extension is allowed, and establish a general condition that must be satisfied by any degrees of freedom tuple (d 1 . d 2 ...d K ) achievable through linear interference alignment. For a symmetric system with M k = M, N k = N, d k = d for all k, this condition implies that the total achievable DoF cannot grow linearly with K, and is in fact no more than K(M + N)/(K + 1). We also show that this bound is tight when the number of antennas at each transceiver is divisible by d, the number of data streams per user.