Antenna Device Power Supply Circuit Isolation

The patent replaces the traditional mechanical/physical radio frequency choke (inductor) with an electrical solution using capacitors connected to ground. This substitution eliminates the need for bulky inductor components while achieving the same isolation function through electrical impedance management. The capacitors provide frequency-dependent isolation without requiring physical space for magnetic core structures.

The patent changes the isolation mechanism from impedance-based (using inductors with specific L values) to capacitance-based (using capacitors with specific C values). By selecting appropriate capacitance values, the system achieves high impedance at RF frequencies for isolation while maintaining low impedance at lower frequencies for power supply operation. This parameter change allows compact implementation without sacrificing isolation effectiveness.

The patent substitutes the physical inductor structure with capacitor elements that can be implemented as small surface-mount components or integrated circuit elements. This replacement allows the isolation function to be achieved with minimal physical dimensions, enabling placement close to the antenna axis without the space requirements of traditional choke inductors.

The patent transitions from a three-dimensional inductor structure with significant height and volume to a two-dimensional capacitor implementation that occupies minimal space on the circuit board plane. This dimensional change allows the isolation components to be positioned close to the antenna structure without protruding into the antenna radiation volume.

The patent changes the impedance characteristic from inductive (frequency-increasing) to capacitive (frequency-decreasing). Capacitors naturally provide high impedance at high frequencies (antenna frequencies) for isolation while maintaining low impedance at low frequencies (active element frequencies) for efficient power supply. This parameter change resolves the contradiction by exploiting the opposite frequency response characteristics of capacitors compared to inductors.

The patent inverts the traditional approach by using capacitors instead of inductors for isolation. While inductors provide increasing impedance with frequency, capacitors provide decreasing impedance with frequency. This inversion allows the system to achieve high impedance at RF frequencies for isolation while maintaining low impedance at power supply frequencies, effectively reversing the impedance-frequency relationship to solve the contradiction.