Degrees of Freedom Region of Wireless X Networks Based on Real Interference Alignment

We consider a single hop wireless X network with K transmitters and J receivers, all with single antenna. Each transmitter conveys for each receiver an independent message. The channel is assumed to have constant coefficients. We develop interference alignment scheme for this setup and derived several achievable degrees of freedom regions. We show that in some cases, the derived region meets a previous outer bound and hence is the DoF region. For our achievability schemes, we divide each message into streams and use real interference alignment on the streams. Several previous results on the DoF region and total DoF for various special cases can be recovered from our result. We also presented several novel extensions that enable us to achieve more points of the DoF region. Next, we consider a network model such that each transmitter emits an arbitrary number of messages and each receiver can request an arbitrary subset of the all the emitted messages. We term this network the X networ...

• Type: Journal
• Year: 2016
• Where: TIT
• Authors: Mahdi Zamanighomi, Zhengdao Wang
• Keywords: Education, TIT 2016