What are the differences between the copper plate structure of fibreglass antennas and the high-frequency PCB structure in terms of performance and application scenarios?

I. Core Performance Differences

1. Signal Transmission Efficiency and Frequency Adaptability

• Copper Plate Structure

• Conductive Advantage: Utilizes pure copper or brass with high conductivity (up to 58×10⁶ S/m), resulting in extremely low conductive loss (≤0.3dB/m). It excels in low-frequency bands (≤300MHz)—the solid metal structure stably maintains signal strength, making it ideal for long-distance (≥1km) communication, such as 433MHz IoT base station coverage.

• High-Frequency Limitation: At frequencies ≥1GHz, the skin depth of copper decreases with increasing frequency (e.g., 2.06μm at 1GHz), increasing signal transmission loss on the metal surface. This leads to reduced gain stability (fluctuations up to ±0.5dB), making it unsuitable for 5G, WiFi6, and other high-frequency scenarios.

• High-Frequency PCB Structure

• High-Frequency Adaptability: Relies on copper foil (18-35μm thick) and low-loss substrates (e.g., polytetrafluoroethylene with εr=2.2-3.5 and tanδ≤0.002), effectively suppressing high-frequency dielectric loss. In the 1-6GHz band, signal transmission loss is only 0.5-1dB/m with gain fluctuations ≤±0.1dB, ensuring superior performance consistency in 5G millimeter-wave and WiFi6E applications.

• Low-Frequency Shortcoming: In low-frequency bands (≤300MHz), longer copper foil microstrip lines are required, increasing PCB size (20% larger than equivalent copper plate structures) and introducing more significant substrate dielectric loss, resulting in lower transmission efficiency than copper plates.

2. Design Flexibility and Integration Capability

• Copper Plate Structure: Frequency characteristics are entirely determined by physical dimensions (length, bending angle). Adjustments require re-cutting and welding, leading to long design cycles (2-4 weeks). Multi-band integration is challenging (requiring stacked metal structures, increasing volume by over 30%), limiting it to single-frequency, fixed-application scenarios (e.g., marine VHF communication antennas).
• High-Frequency PCB Structure: Frequency tuning is achieved through flexible copper foil patterning (microstrip length, patch shape, slot design), enabling multi-band integration (e.g., 2.4GHz+5GHz dual bands on a single PCB). Design iterations are rapid (1-2 weeks), making it suitable for high-frequency, multi-mode devices (e.g., drone telemetry antennas requiring 2.4GHz control and 5.8GHz video signals).

3. Environmental Adaptability and Durability

• Mechanical Strength: Copper plate structures offer high rigidity (withstanding 100N radial force without deformation) and excellent shock/vibration resistance. However, metal surfaces require anti-corrosion plating (nickel or chrome); damaged plating can lead to oxidation in high-humidity environments (reducing gain by 1-2dB within six months), making them suitable for industrial equipment and vehicle-mounted applications with strong vibrations.
• High-Frequency PCB Structure: Relies on fiberglass enclosures for protection. Substrates are brittle, and copper foil may delaminate under severe vibration, limiting use in high-shock environments. However, its superior sealing (no exposed solder joints) and substrate resistance to acids, alkalis, and salt spray extend service life by 3-5 years compared to copper plates in coastal or humid environments (e.g., island-based 5G base station antennas).

4. Volume and Mass Production Cost

• Volume: Copper plate structures are 1.5-2 times larger than equivalent high-frequency PCB structures (e.g., 15cm for 433MHz copper plate vs. 8cm for PCB), suiting space-insensitive fixed installations.
• Mass Production Efficiency: Copper plate fabrication depends on manual bending and welding, with a daily output of ~1,000 units. High-frequency PCBs, produced via batch etching, achieve >100,000 units/day at 70% of the cost of copper plates, making them ideal for consumer electronics requiring large-scale production.

II. Typical Application Scenarios

Summary