[Back]


Talks and Poster Presentations (with Proceedings-Entry):

S. Pratschner, S. Schwarz, M. Rupp:
"Single-User and Multi-User MIMO Channel Estimation for LTE-Advanced Uplink";
Talk: IEEE International Conference on Communications (ICC 2017), Paris, France; 05-21-2017 - 05-25-2017; in: "International Conference on Communications (ICC 2017)", IEEE (ed.); (2017), ISSN: 1938-1883; 1 - 6.



English abstract:
In LTE-Advanced (LTE-A) demodulation reference symbols are employed for pilot aided channel estimation to perform coherent detection. Since these reference symbols are allocated on the same time-frequency positions for all users in Multi-User MIMO (MU-MIMO) operation or for all spatial layers in Single-User MIMO (SU-MIMO), they are designed to be code-domain orthogonal in order to be separable at the receiver. This orthogonality is obtained by cyclically shifting a reference signal base sequence, where the specific cyclic shift values are signaled to each user. In this work we show formal equivalence of SU-MIMO and MU-MIMO for LTE-A uplink in the context of channel estimation. We propose a standard compliant mapping that assigns cyclic shifts to users such that SU-MIMO estimation methods are applicable also for MU-MIMO transmissions. Further we show the trade-off between the number of active users and the channel's frequency selectivity in MU-MIMO operation due to the residual channel estimation error.

German abstract:
In LTE-Advanced (LTE-A) demodulation reference symbols are employed for pilot aided channel estimation to perform coherent detection. Since these reference symbols are allocated on the same time-frequency positions for all users in Multi-User MIMO (MU-MIMO) operation or for all spatial layers in Single-User MIMO (SU-MIMO), they are designed to be code-domain orthogonal in order to be separable at the receiver. This orthogonality is obtained by cyclically shifting a reference signal base sequence, where the specific cyclic shift values are signaled to each user. In this work we show formal equivalence of SU-MIMO and MU-MIMO for LTE-A uplink in the context of channel estimation. We propose a standard compliant mapping that assigns cyclic shifts to users such that SU-MIMO estimation methods are applicable also for MU-MIMO transmissions. Further we show the trade-off between the number of active users and the channel's frequency selectivity in MU-MIMO operation due to the residual channel estimation error.

Keywords:
389_sim


"Official" electronic version of the publication (accessed through its Digital Object Identifier - DOI)
http://dx.doi.org/10.1109/ICC.2017.7996955

Electronic version of the publication:
http://publik.tuwien.ac.at/files/publik_263181.pdf


Created from the Publication Database of the Vienna University of Technology.