Abstract: Cooperative communication is considered as a power-efficient technology for resource-constraint wireless networks. However, its gains often come at a price in terms of extra power consumption for relay running and relaying processing. A new selective cooperative scheme was proposed to satisfy an overall performance requirement so that cooperation is only invoked when necessary. Optimal power allocations under overall symbol-error-rate (SER) constraint and maximum power limit were derived for cooperative schemes. Taking into account extra power, the scheme with minimum overall power was adopted for a source-destination pair. Simulation results show that the proposed schemes are more power-efficient than the conventional cooperative scheme.

Key words: cooperative communication, power-efficiency, relay selecting