Angle-of-Arrival Estimation Using Difference Beams in Localized Hybrid Arrays.

Area of Science:

• Signal Processing
• Wireless Communications
• Array Signal Processing

Background:

• Localized hybrid arrays face challenges in angle-of-arrival (AoA) estimation due to phase ambiguity and noise sensitivity.
• Existing methods struggle to accurately resolve AoA in complex, localized array structures.

Purpose of the Study:

• To propose a novel phase shift design for unambiguous AoA estimation in localized hybrid arrays.
• To enhance the accuracy and robustness of AoA estimation algorithms in the presence of phase ambiguity and noise.

Main Methods:

• A new phase shift design is introduced, enabling subarrays to utilize difference beam steering in two potential AoA directions.
• Calibration of cross-correlations and improved phase offset estimation between subarrays are facilitated.
• Two unambiguous AoA estimation schemes are proposed, differentiated by the ratio of antennas per subarray (N) to phase shifts per symbol (K) – specifically, even and odd N/K ratios.

Main Results:

• The proposed phase shift design significantly improves AoA estimation accuracy compared to existing methods.
• Enhanced performance is particularly noted when the ratio N/K is even.
• The developed schemes effectively resolve phase ambiguity inherent in localized hybrid arrays.

Conclusions:

• The novel phase shift design offers a robust solution for unambiguous AoA estimation in localized hybrid arrays.
• The proposed schemes provide a significant advancement in estimation accuracy, especially under specific N/K ratio conditions.
• This work contributes to improved performance in wireless communication systems relying on precise AoA determination.