How many columns does the large vertical array (LVA) antenna have?

• A. 25
• B. 30
• C. 40
• D. 35

Answer: (D)

The number of columns in the large vertical array defines how tall the antenna aperture is and directly shapes the elevation beam pattern. Each column carries its own set of radiating elements, and by phasing across all columns you form the vertical beam that covers different elevation angles. Designing the LVA with a fixed count of columns is about balancing elevation coverage, gain, and practical constraints like weight and mechanical complexity. Thirty-five columns provide the required vertical aperture to achieve the target elevation beamwidth and gain for reliable detection of aircraft at various altitudes around the airfield. Fewer columns would make the beam broader in elevation, reducing resolution at higher angles, while more columns would add unnecessary complexity and cost without proportional performance gains. Thus, thirty-five columns meet the system’s performance requirements and design compromises.