Direct-conversion transceivers are the predominating architecture in current mobile communication systems. Despite many advantages, this topology suffers from unavoidable
mismatches in the analog part, which cause imbalance between
the in-phase and quadrature (I/Q) component. In this paper we
present a novel fully digital, blind I/Q imbalance compensation algorithm, which features extremely low computational complexity
and a high compensation performance for a wide range of input
signal types. Different to many state-of-the-art compensation
schemes, the approach is not based on a gradient descent
optimization and does not require any global feedback. This
simplifies the implementation at high data rates and reduces the
configuration effort to a minimum. For comparison we examine
an existing method of moments based estimator with similar
properties for which we also provide detailed insights beyond
available literature. For both algorithms we provide a rigorous
mathematical analysis, which is supported by simulations with
focus on various Long-Term Evolution (LTE) signal types. In
addition, hardware architectures, including field-programmable
gate array (FPGA) verification, are presented for both algorithms.
Sprache der Kurzfassung:
Englisch
Journal:
IEEE Transactions on Circuits and Systems I: Regular papers