The paper discusses the performance of a MIMO-extended UMTS-FDD downlink with a 2x2 and a 4x4 antenna configuration. An analytical expression for the average signal to interference ratio (SIR) of a space-time (ST) RAKE receiver in an interference dominated environment is derived. Simulations are used to assess the BER performance with the number of concurrent users as a parameter. The results are compared to a single antenna link with equivalent data rate. In addition to that, a linear zero forcing (ZF) and an MMSE MIMO equalizer receiver is evaluated and compared to the ST-RAKE. It is shown that both methods can successfully mitigate the significant performance Imitation due to self interference (SI) and multiple access interference (MAI).
Tobias Kippenberg, Maxim Karpov, Zhe Zhao, Hao Song, Xinzhou Su
Olivier Sauter, Ambrogio Fasoli, Basil Duval, Stefano Coda, Jonathan Graves, Yves Martin, Duccio Testa, Patrick Blanchard, Alessandro Pau, Cristian Sommariva, Henri Weisen, Richard Pitts, Yann Camenen, Jan Horacek, Javier García Hernández, Marco Wischmeier, Nicola Vianello, Mikhail Maslov, Federico Nespoli, Yao Zhou, David Pfefferlé, Davide Galassi, Antonio José Pereira de Figueiredo, Jonathan Marc Philippe Faustin, Liang Yao, Dalziel Joseph Wilson, Hamish William Patten, Samuel Lanthaler, Bernhard Sieglin, Otto Asunta