TY - JOUR T1 - Designing incoherent frames through convex techniques for optimized compressed sensing JF - IEEE Transactions on Signal Processing Y1 - 2016 A1 - Cristian Rusu A1 - Nuria González-Prelcic KW - compass KW - compressed sensing VL - 64 IS - 9 ER - TY - CONF T1 - Hybrid precoders and combiners for mmWave MIMO systems with per-antenna power constraints T2 - IEEE Global Telecommunications Conf. (GLOBECOM) Y1 - 2016 A1 - R. López-Valcarce A1 - Nuria González-Prelcic A1 - Cristian Rusu A1 - R. W. Heath, Jr KW - compass KW - mmWave AB -
This paper considers the design of hybrid precoders
and combiners for mmWave MIMO systems with per-antenna
power constraints and the additional limitations introduced by
the phase-shifting network in the analog processing stage. Previous
hybrid designs were obtained using a total power constraint,
but in practical implementations per-antenna constraints are
more realistic, specially at mmWave, given the large number of
power amplifiers used in the transmit array. Assuming perfect
channel knowledge, we obtain first an approximation to the alldigital
solution for the precoder and the combiner given the
per-antenna constraints. Then, we develop a new method for the
design of the hybrid precoder and combiner which attempts to
match such all-digital approximation. Simulation results show
the effectiveness of the proposed approach, which performs close
to the all-digital solution.
JF - IEEE Global Telecommunications Conf. (GLOBECOM) ER - TY - JOUR T1 - Low complexity hybrid precoding strategies for millimeter wave communication systems JF - IEEE Trans. Wireless Communications Y1 - 2016 A1 - Cristian Rusu A1 - Roi Méndez-Rial A1 - Nuria González-Prelcic A1 - Robert W. Heath Jr. KW - compass KW - mmWave AB -

Millimeter communication systems use large antenna arrays to provide good average received power and to take advantage of multi-stream MIMO communication. Unfortunately, due to power consumption in the analog front-end, it is impractical to perform beamforming and fully digital precoding at baseband. Hybrid precoding/combining architectures have been proposed to overcome this limitation. The hybrid structure splits the MIMO processing between the digital and analog domains, while keeping the performance close to that of the fully digital solution. In this paper, we introduce and analyze several algorithms that efficiently design hybrid precoders and combiners starting from the known optimum digital precoder/combiner, which can be computed when perfect channel state information is available. We propose several low complexity solutions which provide different trade-offs between performance and complexity. We show that the proposed iterative solutions perform better in terms of spectral efficiency and/or are faster than previous methods in the literature. All of them provide designs which perform close to the known optimal digital solution. Finally, we study the effects of quantizing the analog component of the hybrid design and show that even with coarse quantization, the average rate performance is good.

VL - 15 IS - 12 ER - TY - JOUR T1 - Properties of real and complex ETFs and their application to the design of low coherence frames JF - Linear Algebra and its Applications Y1 - 2016 A1 - Cristian Rusu A1 - Nuria González-Prelcic A1 - Robert W. Heath Jr. VL - 508 UR - http://www.sciencedirect.com/science/article/pii/S0024379516302555 ER - TY - CONF T1 - An attack on antenna subset modulation for millimeter-wave communication T2 - IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP) Y1 - 2015 A1 - Cristian Rusu A1 - Nuria González-Prelcic A1 - Robert W. Heath Jr. KW - adversarial signal processing KW - compass KW - mmWave AB -

Antenna subset modulation (ASM) is a physical layer security technique that is well suited for millimeter wave communication systems. The key idea is to vary the radiation pattern at the symbol rate by selecting one from a subset of patterns with a similar main lobe and different side lobes. This paper shows that ASM is not robust to an eavesdropper that makes multiple simultaneous measurements at multiple angles. The measurements are combined and used to formulate an estimation problem to undo the effects of the side lobe randomization. Simulations show the performance of the estimation algorithms and how the eavesdropper can effectively recover the information if the signal-to-noise ratio exceeds a certain threshold. Using fewer active radio frequency chains makes it harder for the attacker to recover the transmit symbol, at the expense of more grating lobes.

JF - IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP) PB - IEEE CY - Brisbane, Australia ER - TY - CONF T1 - Dictionary-free Hybrid Precoders and Combiners for mmWave MIMO Systems T2 - IEEE Int. Workshop on Signal Processing Advances in Wireless Communications (SPAWC) Y1 - 2015 A1 - Roi Méndez-Rial A1 - Cristian Rusu A1 - Nuria González-Prelcic A1 - Robert W. Heath Jr. KW - compass KW - mmWave JF - IEEE Int. Workshop on Signal Processing Advances in Wireless Communications (SPAWC) PB - IEEE CY - Stockholm, Sweden ER - TY - CONF T1 - Low Complexity Hybrid Sparse Precoding and Combining in Millimeter Wave MIMO Systems T2 - IEEE Int. Conference on Communications (ICC) Y1 - 2015 A1 - Cristian Rusu A1 - Roi Méndez-Rial A1 - Nuria González-Prelcic A1 - Robert W. Heath Jr. KW - compass KW - mmWave JF - IEEE Int. Conference on Communications (ICC) PB - IEEE CY - London, UK ER -