Optimum power allocation for parallel Gaussian channels with arbitrary input distributions

The mutual information of independent parallel Gaussian-noise channels is maximized, under an average power constraint, by independent Gaussian inputs whose power is allocated according to the waterfilling policy. In practice, discrete signalling constellations with limited peak-to-average ratios (m...

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Detalles Bibliográficos
Autores: Lozano Solsona, Angel, Tulino, Antonia M., Verdú, Sergio
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2006
País:España
Institución:Universitat Pompeu Fabra
Repositorio:Repositorio Digital de la UPF
OAI Identifier:oai:repositori.upf.edu:10230/16123
Acceso en línea:http://hdl.handle.net/10230/16123
http://dx.doi.org/10.1109/TIT.2006.876220
Access Level:acceso abierto
Palabra clave:Ràdio -- Interferències
Tractament del senyal
Gaussian Channels
Power Allocation
Waterfilling
Channel Capacity
Mutual Information
MMSE
Descripción
Sumario:The mutual information of independent parallel Gaussian-noise channels is maximized, under an average power constraint, by independent Gaussian inputs whose power is allocated according to the waterfilling policy. In practice, discrete signalling constellations with limited peak-to-average ratios (m-PSK, m-QAM, etc) are used in lieu of the ideal Gaussian /nsignals. This paper gives the power allocation policy that maximizes the mutual information /nover parallel channels with arbitrary input distributions. Such policy admits a graphical interpretation, referred to as mercury/waterfilling, which generalizes the waterfilling solution and allows retaining some of its intuition. The relationship between mutual information of Gaussian channels and nonlinear minimum mean-square error proves key to solving the power allocation problem.