Performance of Interference Rejection Combining Receiver Employing Minimum Mean Square Error Filter for Licensed-Assisted Access

Jumpei YAMAMOTO  Shunichi BUSHISUE  Nobuhiko MIKI  

IEICE TRANSACTIONS on Communications   Vol.E101-B   No.1   pp.137-145
Publication Date: 2018/01/01
Online ISSN: 1745-1345
DOI: 10.1587/transcom.2017EBP3045
Type of Manuscript: PAPER
Category: Fundamental Theories for Communications
Licensed-Assisted Access,  LTE-advanced pro,  interference rejection combining receiver,  

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To support the rapid increase of mobile traffic, the LTE-based air interface is expected to be employed in the unlicensed spectrum known as “Licensed-Assisted Access (LAA).” The LAA terminal, which employs an LTE-based air interface, suffers from interference from WiFi access points as well as the LAA base station. The interference rejection combining (IRC) receiver, which employs a linear minimum mean square error (MMSE) filter, can suppress this interference from WiFi access points in addition to that of the LAA base station. The IRC receiver is effective, since it requires no knowledge of the interference, which is generally difficult to obtain for different systems. In this paper, we use a link-level simulation to evaluate the performance of the IRC receiver in suppressing the interference from WiFi access points, and show that the IRC receiver can effectively cancel the interference from WiFi systems as well as LTE systems, although we observed a slight performance degradation due to the covariance matrix estimation error caused by the WiFi interference fluctuation in the frequency-domain.