Quantum mechanics

Sparse array

Algorithm

Control (management)

Engineering

Coupling (piping)

Telecommunications

Set (abstract data type)

Computer science

Antenna (radio)

Beamforming

Mechanical engineering

Physics

Degrees of freedom (physics and chemistry)

Mathematics

Antenna array

Electronic engineering

Artificial intelligence

Array gain

Combinatorics

Direction of arrival

Programming language

Sensor array

Topology (electrical circuits)

Control theory (sociology)

Machine learning

Coprime integers

IEEE Transactions on Signal Processing

Recently, nested and coprime arrays have attracted considerable interest due to their capability of providing increased array aperture, enhanced degrees of freedom (DOFs), and reduced mutual coupling effect compared to uniform linear arrays (ULAs). These features are critical to improving the performance of direction-of-arrival estimation and adaptive beamforming. In this paper, a new sparse array configuration based on the maximum inter-element spacing constraint (MISC) is proposed. The MISC array configuration generally consists of three sparse ULAs plus two separate sensors that are appropriately placed. The MISC array configurations are designed based on the inter-element spacing set, which, for a given number of sensors, is uniquely determined by a closed-form expression. We also derive closed-form expressions for the number of uniform DOFs of the MISC arrays with any number of sensors. Compared with the existing sparse arrays, the MISC array enjoys two important advantages, namely, providing a higher number of DOFs and reducing the mutual coupling effects. Numerical simulations are conducted to verify the superiority of the MISC array over other sparse arrays.

MISC Array: A New Sparse Array Design Achieving Increased Degrees of Freedom and Reduced Mutual Coupling Effect