Marques, Antonio G.Wang, XinGiannakis, Georgios B.2009-01-202009-01-202008-09-01IEEE Transac. on Signal Processing, vol. 56, no.8, pp. 4446-44571053-587Xhttp://hdl.handle.net/10115/1806We minimize average transmit power with finite-rate feedback for coherent communications in a wireless sensor network (WSN), where sensors communicate with a fusion center using adaptive modulation and coding over a wireless fading channel. By viewing the coherent WSN setup as a distributed space¿time multiple-input single-output (MISO) system, we present optimal distributed beamforming and resource allocation strategies when the full (F-) channel state information at the transmitters (CSIT) is available through a feedback channel. We also develop optimal adaptive transmission policies and design optimal quantizers for the finite-rate feedback case where the sensors only have quantized (Q-) CSIT, or, each sensor has F-CSIT of its own link with the FC but only Q-CSIT of other sensors. Numerical results confirm that our novel finite-rate feedback-based strategies achieve near-optimal power savings based on even a small number of feedback bits.enAtribución-NoComercial-SinDerivadas 3.0 Españahttp://creativecommons.org/licenses/by-nc-nd/3.0/es/Telecomunicacionesinfo:eu-repo/semantics/articleinfo:eu-repo/semantics/openAccess3325 Tecnología de las Telecomunicaciones