Transmit-Receive Sparse Synthesis of Linear Frequency Diverse Array in Range-Angle Space Using Genetic Algorithm.

Area of Science:

• Antenna Theory
• Signal Processing
• Electromagnetics

Background:

• Conventional phased arrays (PA) offer angle-only beamforming.
• Frequency diversity array (FDA) enhances beamforming flexibility by adding range dimension control.
• High-resolution FDA typically requires numerous elements, leading to high costs.

Purpose of the Study:

• Investigate transmit-receive beamforming for sparse FDA in range and angle dimensions.
• Develop a cost-effective method to reduce element count while preserving antenna resolution.
• Achieve low sidelobe levels (SLL) in sparse FDA configurations.

Main Methods:

• Derived and analyzed the joint transmit-receive signal formula for time-varying FDA.
• Employed a cost-effective signal processing diagram.
• Utilized a Genetic Algorithm (GA) for low SLL transmit-receive beamforming, incorporating array element positions into optimization.
• Investigated sparse linear FDAs with sinusoidally (sin-FO) and logarithmically (log-FO) varying frequency offsets.

Main Results:

• Demonstrated that 50% of elements can be saved in linear FDAs.
• Achieved this reduction with a minimal SLL increment (less than 1 dB).
• Resultant SLLs were below -9.6 dB for sin-FO linear-FDA and -12.9 dB for log-FO linear-FDA.

Conclusions:

• Sparse FDA enables substantial cost reduction without significant performance degradation.
• The proposed GA-based method effectively optimizes sparse FDA for range-angle beamforming.
• This approach offers a practical solution for high-resolution, cost-sensitive array antenna applications.