Superimposed signaling inspired channel estimation in full-duplex systems
Date
Authors
Koohian, Abbas
Mehrpouyan, Hani
Nasir, Ali A.
Blostein, Steven D.
Durrani, Salman
Journal Title
Journal ISSN
Volume Title
Publisher
Institute of Electrical and Electronics Engineers (IEEE)
Abstract
Residual self-interference (SI) cancellation in the digital baseband is an important problem in full-duplex (FD)
communication systems. In this paper, we propose a new technique for estimating the SI and communication
channels in a FD communication system, which is inspired from superimposed signaling. In our proposed technique,
we add a constant real number to each constellation point of a conventional modulation constellation to yield
asymmetric shifted modulation constellations with respect to the origin. We show mathematically that such
constellations can be used for bandwidth efficient channel estimation without ambiguity. We propose an expectation
maximization (EM) estimator for use with the asymmetric shifted modulation constellations. We derive a closed-form
lower bound for the mean square error (MSE) of the channel estimation error, which allows us to find the minimum
shift energy needed for accurate channel estimation in a given FD communication system. The simulation results
show that the proposed technique outperforms the data-aided channel estimation method, under the condition that
the pilots use the same extra energy as the shift, both in terms of MSE of channel estimation error and bit error rate.
The proposed technique is also robust to an increasing power of the SI signal.
Description
Keywords
Full-duplex systems, Channel estimation, Self-interference cancellation, Superimposed signaling
Citation
Collections
Source
EURASIP Journal on Advances in Signal Processing
Type
Journal article
Book Title
Entity type
Access Statement
Open Access
License Rights
Restricted until
Downloads
File
Description