Chun-Lin Liu – Topics – Hourglass Arrays (2D)

• Toolkit for coarray MUSIC and coarray interpolation

• Sparse array design with reduced mutual coupling

  • Super nested arrays (1-D)

  • Hourglass arrays (2-D)

• Cramér-Rao bounds for sparse arrays

• Others

Hourglass Arrays

Planar arrays with 49 sensors, including uniform linear arrays (URA), billboard arrays, 2D nested arrays, open box arrays (OBA), half open box arrays (HOBA), and hourglass arrays. (View larger)

Linear (1D) sparse arrays such as nested arrays and minimum redundancy arrays have hole-free difference coarrays with virtual sensor elements, where is the number of physical sensors. The hole-free property makes it easier to perform beamforming and DOA estimation in the coarray domain which behaves like an uniform linear array. The property implies that uncorrelated sources can be identified. For the 2D case, planar sparse arrays with hole-free coarrays having elements have also been known for a long time. These include billboard arrays, open box arrays (OBA), and 2D nested arrays. Their merits are similar to those of the 1D sparse arrays mentioned above, although identifiability claims regarding sources have to be handled with more care in 2D.

This paper introduces new planar sparse arrays with hole-free coarrays having elements just like the OBA, with the additional property that the number of sensor pairs with small spacings such as decreases, reducing the effect of mutual coupling. The new arrays include half open box arrays (HOBA), half open box arrays with two layers (HOBA-2), and hourglass arrays. Among these, simulations show that hourglass arrays have the best estimation performance in presence of mutual coupling.

Our Papers

1. C.-L. Liu and P. P. Vaidyanathan, ‘‘Hourglass Arrays, and Other Novel 2D Sparse Arrays with Reduced Mutual Coupling,’’ IEEE Trans. on Signal Processing, vol. 65, no. 13, pp. 3369-3383, July 2017.

   1. DOI and Full text

   2. Interactive Interface.

   3. Sample code for Fig. 7. Please execute main_2D_DOA_estimation.m for the plots. (Last update: July 31, 2017)

   4. Supplementary document.

2. C.-L. Liu and P. P. Vaidyanathan, ‘‘Two-Dimensional Sparse Arrays with Hole-Free Coarray and Reduced Mutual Coupling,’’ in Proc. of the 50th Asilomar Conference on Signals, Systems, and Computers, Pacific Grove, CA, Nov. 2016.
   (The First Prize in Best Student Paper Award)

   1. DOI and Full text

   2. Poster and Slides