Energy and spectral efficiencies trade-off with filter optimisation in multiple access interference-aware networks

• Published in: Transactions on emerging telecommunications technologies 2015-04, Vol.26 (4), p.670-685
• Main Authors: Souza, Álvaro R.C., Abrão, Taufik, Sampaio, Lucas H., Jeszensky, Paul Jean E., Pérez-Romero, Jordi, Casadevall, Ferran
• Format: Article
• Language: English
• ISSN: 2161-3915; 2161-3915
• DOI: 10.1002/ett.2698

In this contribution, the optimised deployment of both spectrum and energy resources scarcely available in the mobile multiple access systems has been analysed, with special attention to the impact of the filter design on the energy efficiency (EE) of code division multiple access networks. Putting into perspective two conflicting metrics, namely throughput maximisation and power consumption minimisation, the distributed EE utility function is formulated. We also show that the best EE versus spectral efficiency trade‐off is achievable when each node allocates exactly the power necessary to attain the maximum EE. In order to demonstrate the validity of our analysis, a low‐complexity energy‐spectral‐efficient algorithm based on distributed instantaneous signal‐to‐interference‐plus‐noise ratio level is developed, and the impact of single and multi‐user detection filters on the EE–spectral efficiency trade‐off is extensively analysed by numerical simulation. Copyright © 2013 John Wiley & Sons, Ltd. Energy Efficiency (EE) optimisation problem in direct sequence/code division multiple access is formulated from the perspective of two conflicting metrics, throughput maximisation and power consumption minimisation; low‐complexity algorithm based on distributed signal‐to‐interference‐plus‐noise ratios (SINRs) is developed. The best EE‐spectral efficiency (SE) trade‐off is achievable when exactly the power necessary to attain the max‐EE is allocated, while SE can be determined by the attainable rate. Interestingly, under max‐EE point equilibrium, the SINR approaches to a constant low‐value when the multiple access interference power level increases considerably.