Antenna Packing in Low-Power Systems: Communication Limits and Array Design
- 4 January 2008
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Transactions on Information Theory
- Vol. 54 (1), 429-440
- https://doi.org/10.1109/tit.2007.911175
Abstract
In this correspondence, we study design of transceiver antenna arrays and its impact on spectral efficiency of low-power systems. Our primary motivation is construction of practical and portable multi-antenna configurations with a very small and a-priori fixed volume for placing antennas. Using spectral efficiency as a target metric for array optimization, we show that any array configuration, transmit or receive, can be characterized via a parameter that we interpret as ldquoeffective degrees of freedom.rdquo For any array configuration, effective degrees of freedom describes an equivalent uncorrelated array, which results in the same low-power behavior of spectral efficiency. Joint optimization of transmit and receive antenna configurations decouples into maximizing effective degrees of freedom for transmitter and receiver separately. To achieve this goal, we introduce and study a theoretical benchmark of ldquolimiting degrees of freedom, rdquo which is the least upper bound on effective degrees of freedom, evaluated over all configurations with finite number of antennas. Limiting degrees of freedom therefore describes the best possible performance for any transceiver array which confines its elements inside a given space. We compute a closed-form expression for limiting degrees of freedom of a circular geometry. Finally, we present numerical procedure and examples for designing linear and square arrays with nonuniform spacing, which typically exhibit significant spectral efficiency gains over uniform arrays.Keywords
This publication has 20 references indexed in Scilit:
- Antenna Packing in Low-Power Systems: Communication Limits and Array DesignIEEE Transactions on Information Theory, 2008
- Degrees of Freedom in Multiple-Antenna Channels: A Signal Space ApproachIEEE Transactions on Information Theory, 2005
- Impact of correlation and coupling on the capacity of MIMO systemsPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2004
- Mutual Coupling in MIMO Wireless Systems: A Rigorous Network Theory AnalysisIEEE Transactions on Wireless Communications, 2004
- Capacity limits of dense palm-sized MIMO arraysPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2004
- Spectral efficiency in the wideband regimeIEEE Transactions on Information Theory, 2002
- Capacity scaling in MIMO wireless systems under correlated fadingIEEE Transactions on Information Theory, 2002
- Elements of Information TheoryPublished by Wiley ,2001
- Capacity of a mobile multiple-antenna communication link in Rayleigh flat fadingIEEE Transactions on Information Theory, 1999
- Optimum sequence multisets for synchronous code-division multiple-access channelsIEEE Transactions on Information Theory, 1994