Frequency-Domain Interpolation of the Zero-Forcing Matrix in Massive MIMO-OFDM
2016 (English)In: 2016 IEEE 17TH INTERNATIONAL WORKSHOP ON SIGNAL PROCESSING ADVANCES IN WIRELESS COMMUNICATIONS (SPAWC), IEEE , 2016Conference paper (Refereed)
We consider massive multiple input multiple output (MIMO) systems with orthogonal frequency division multiplexing (OFDM) that use zero-forcing (ZF) to combat interference. To perform ZF, large dimensional pseudo-inverses have to be computed. In this paper, we propose a discrete Fourier transform (DFT)-interpolation-based technique where substantially fewer ZF matrix computations have to be done with very little deterioration in data rate compared to computing an exact ZF matrix for every subcarrier. We claim that it is enough to compute the ZF matrix at L(amp;lt;amp;lt; N) selected subcarriers where L is the number of resolvable multipaths and N is the total number of subcarriers and then interpolate. The proposed technique exploits the fact that in the massive MIMO regime, the ZF impulse response consists of L dominant components. We benchmark the proposed method against full inversion, piecewise constant and linear interpolation methods and show that the proposed method achieves a good tradeoff between performance and complexity.
Place, publisher, year, edition, pages
IEEE , 2016.
IEEE International Workshop on Signal Processing Advances in Wireless Communications, ISSN 2325-3789
Massive MIMO; interpolation; zero-forcing
IdentifiersURN: urn:nbn:se:liu:diva-132691DOI: 10.1109/SPAWC.2016.7536907ISI: 000382942700182ISBN: 978-1-5090-1749-2 (print)OAI: oai:DiVA.org:liu-132691DiVA: diva2:1048138
17th IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC)