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Hole-Free Nested Array with Three Sub-ULAs for Direction of Arrival Estimation
Yule Zhang1, Guoping Hu2, Hao Zhou2
1Graduate College, Air Force Engineering University, Xi'an 710051, China.
Sensors (Basel, Switzerland)
|June 10, 2023
Summary
This study introduces a novel hole-free nested array (NA-TS) for improved direction of arrival (DOA) estimation. The proposed array offers significantly more degrees of freedom (DOFs) than existing methods, enhancing sparse array performance.
Area of Science:
- Signal Processing
- Array Signal Processing
- Electromagnetics
Background:
- Sparse arrays enable source identification exceeding sensor count.
- Hole-free difference co-arrays (DCAs) offer large degrees of freedom (DOFs).
- Existing nested arrays have limitations in DOFs.
Purpose of the Study:
- Propose a novel hole-free nested array with three sub-uniform line arrays (NA-TS).
- Analyze the configuration and DOFs of the proposed NA-TS.
- Demonstrate superior direction of arrival (DOA) estimation performance.
Main Methods:
- Developed a novel hole-free nested array configuration (NA-TS).
- Derived closed-form expressions for optimal configuration and DOFs.
- Utilized 1D and 2D representations for detailed analysis.
- Compared NA-TS with existing hole-free nested arrays.
Main Results:
- NA-TS configuration is detailed, showing nested array (NA) and improved nested array (INA) as special cases.
- DOFs of NA-TS are a function of sensor count and the third sub-uniform line array (sub-ULA).
- NA-TS provides more DOFs compared to previously proposed hole-free nested arrays.
- Numerical examples confirm superior DOA estimation performance of NA-TS.
Conclusions:
- The proposed NA-TS is an effective configuration for sparse arrays.
- NA-TS offers enhanced DOFs, crucial for advanced DOA estimation.
- The novel array design leads to superior performance in identifying multiple sources.
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