Title :
A General Rate Duality of the MIMO Multiple Access Channel and the MIMO Broadcast Channel
Author :
Hunger, Raphael ; Joham, Michael
Author_Institution :
Assoc. Inst. for Signal Process., Tech. Univ. Munchen, Munich
Abstract :
We present a general rate duality between the multiple access channel (MAC) and the broadcast channel (BC) which is applicable to systems with and without nonlinear interference cancellation. Different to the state-of-the-art rate duality with interference subtraction from Vishwanath et al., the proposed duality is filter-based instead of covariance-based and exploits the arising unitary degree of freedom to decorrelate every point- to-point link. Therefore, it allows for noncooperative stream-wise decoding which reduces complexity and latency. Moreover, the conversion from one domain to the other does not exhibit any dependencies during its computation making it accessible to a parallel implementation instead of a serial one. We additionally derive a rate duality for systems with multi-antenna terminals when linear filtering without interference (pre-)subtraction is applied and the different streams of a single user are not treated as self-interference. Both dualities are based on a framework already applied to a mean-square-error duality between the MAC and the BC. Thanks to this novel rate duality, any rate-based optimization with linear filtering in the BC can now be handled in the dual MAC where the arising expressions lead to more efficient algorithmic solutions than in the BC due to the alignment of the channel and precoder indices.
Keywords :
MIMO communication; broadcast channels; channel coding; decoding; mean square error methods; multi-access systems; multiuser channels; optimisation; MIMO broadcast channel; MIMO multiple access channel; broadcast channel; filter-based duality; linear filtering; mean-square-error method; multiantenna terminals; multiple access channel; noncooperative stream-wise decoding; nonlinear interference cancellation; point- to-point link decorrelation; rate-based optimization; state-of-the-art rate; unitary degree of freedom; Broadcasting; Concurrent computing; Decoding; Decorrelation; Delay; Filtering algorithms; Interference cancellation; MIMO; Maximum likelihood detection; Nonlinear filters;
Conference_Titel :
Global Telecommunications Conference, 2008. IEEE GLOBECOM 2008. IEEE
Conference_Location :
New Orleans, LO
Print_ISBN :
978-1-4244-2324-8
DOI :
10.1109/GLOCOM.2008.ECP.178