High-Frequency Circuit Switching for Multi-Band Isolation

The patent combines multiple filter functions into a single diplexer structure. The diplexer integrates first and second filters that handle different frequency bands, allowing simultaneous transmission with high isolation while occupying less space than separate filter circuits would require. This merging of functions directly addresses the contradiction by achieving high isolation without proportionally increasing circuit area.

The diplexer is designed to handle multiple frequency bands (first band and second band) simultaneously through a single circuit structure. By making the filter circuit universal across multiple bands, the patent avoids needing separate dedicated circuits for each band, thereby maintaining high isolation between bands while keeping the overall circuit size compact.

The diplexer circuit is segmented into distinct filter paths (first filter for first band, second filter for second band) that are integrated within a compact structure. This segmentation allows each band to be handled independently with proper isolation, while the overall segmented structure is arranged to minimize total circuit area. The switch circuit also segments the connection paths to prevent unwanted coupling between bands.

The diplexer acts as an intermediary structure between the power amplifier circuits and the antenna terminals. It mediates the signal paths for different bands, providing isolation between bands while maintaining a compact footprint. The switch circuit also serves as an intermediary that controls connection states to ensure isolation is maintained without requiring large physical separation between circuit elements.