Impact of residual transmit RF impairments on training-based MIMO systems
2014 (English)In: 2014 IEEE International Conference on Communications, ICC 2014, 2014, 4741-4746 p.Conference paper (Refereed)
Radio-frequency (RF) impairments, that exist intimately in wireless communications systems, can severely degrade the performance of traditional multiple-input multiple-output (MIMO) systems. Although compensation schemes can cancel out part of these RF impairments, there still remains a certain amount of impairments. These residual impairments have fundamental impact on the MIMO system performance. However, most of the previous works have neglected this factor. In this paper, a training-based MIMO system with residual transmit RF impairments (RTRI) is considered. In particular, we derive a new channel estimator for the proposed model, and find that RTRI can create an irreducible estimation error floor. Moreover, we show that, in the presence of RTRI, the optimal training sequence length can be larger than the number of transmit antennas, especially in the low and high signal-to-noise ratio (SNR) regimes. An increase in the proposed approximated achievable rate is also observed by adopting the optimal training sequence length. When the training and data symbol powers are required to be equal, we demonstrate that, at high SNRs, systems with RTRI demand more training, whereas at low SNRs, such demands are nearly the same for all practical levels of RTRI.
Place, publisher, year, edition, pages
2014. 4741-4746 p.
Communication channels (information theory), Estimation, Signal to noise ratio, Wireless telecommunication systems, Compensation scheme, Estimation errors, High signalto-noise ratios (SNR), Multiple-input-multiple-output systems, Optimal training sequences, Radio frequencies, Transmit antenna, Wireless communications system, MIMO systems
IdentifiersURN: urn:nbn:se:kth:diva-167567DOI: 10.1109/ICC.2014.6884070ScopusID: 2-s2.0-84907000792ISBN: 9781479920037OAI: oai:DiVA.org:kth-167567DiVA: diva2:816126
2014 1st IEEE International Conference on Communications, ICC 2014, 10 June 2014 through 14 June 2014, Sydney, NSW
QC 201506022015-06-022015-05-222015-06-02Bibliographically approved