Coherent Multiuser Relaying with Partial Relay Cooperation
ReferenceIEEE Wireless Communication and Networking Conference, Las Vegas, NV, USA, Apr. 2006
AbstractWe consider a heterogeneous wireless ad hoc network. All nodes are within radio range and may employ an arbitrary number of antennas. Our goal is to achieve a distributed spatial multiplexing gain in this scenario without introducing additional delay. To this end we let 2N of the nodes form N source/destination pairs, that concurrently communicate on the same physical channel. Other nodes in the network act as coherent amplify&forward relays. We use relaying to minimize the cochannel interference between different links (coherent multiuser relaying) and to achieve diversity. Some of the relays may be able to exchange received signal information e.g. by utilizing a suitable short range wireless technology such as Bluetooth (partial cooperation). The main contributions of this paper are (i) a unified derivation of coherent multiuser relaying with an arbitrary number of relays and an arbitrary cooperation pattern and (ii) a novel block zero forcing relay gain allocation for this setting. The derivation naturally includes any combination of multi-antenna (MIMO) nodes. The gain allocation is based on a subspace approach and the complexity is essentially independent of the number of relays. Performance results show, that it achieves the full spatial multiplexing gain N. If the number of relays and/or cooperations exceeds a minimum value, we additionally obtain a distributed diversity gain and array gain for each source/destination link.
Keywordsrelay; gain allocation; spatial multiplexing; diversity; ad hoc network
Download this document:
Copyright Notice: © 2006 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.
This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.