Impedance matching circuit and transmitter
AssigneePacific Industrial Co., Ltd.
InventorMakoto Kuno
Life of this patent
Estimating the term…
Abstract
A matching circuit (31) includes a first parallel resonance circuit (32), a second parallel resonance circuit (36), a first matching unit (35), and a second matching unit (39). The resonance frequency of the first parallel resonance circuit (32) is a first frequency. The resonance frequency of the second parallel resonance circuit (36) is a second frequency. The first matching unit (35) is connected in series with the first parallel resonance circuit (32). The second matching unit (39) is connected in series with the second parallel resonance circuit (36). The first parallel resonance circuit (32) and the second parallel resonance circuit (36) are connected in parallel with each other and connected in series with the transmission antenna (27).
Claims4
An impedance matching circuit connected to an antenna, the impedance matching circuit comprising:
- a first parallel resonance circuit including a first coil and a first capacitor that are connected in parallel with each other, the first parallel resonance circuit having a resonance frequency that is a first frequency;
- a second parallel resonance circuit including a second coil and a second capacitor that are connected in parallel with each other, the second parallel resonance circuit having a resonance frequency that is a second frequency;
- a first matching circuit configured to perform impedance matching between the antenna and a wireless communication circuit at the second frequency, the first matching circuit being connected in series with the first parallel resonance circuit;
- and
- a second matching circuit configured to perform impedance matching between the antenna and the wireless communication circuit at the first frequency, the second matching circuit being connected in series with the second parallel resonance circuit,
- wherein the first parallel resonance circuit and the second parallel resonance circuit are connected in parallel with each other and connected in series with the antenna.
A transmitter attached to a wheel of a vehicle, the transmitter comprising:
- a transmission antenna;
- a transmission circuit;
- and
- an impedance matching circuit that performs impedance matching between the transmission antenna and the transmission circuit, wherein
- the impedance matching circuit includes:
- a first parallel resonance circuit including a first coil and a first capacitor that are connected in parallel with each other, the first parallel resonance circuit having a resonance frequency that is a first frequency;
- a second parallel resonance circuit including a second coil and a second capacitor that are connected in parallel with each other, the second parallel resonance circuit having a resonance frequency that is a second frequency;
- a first matching circuit configured to perform impedance matching between the transmission antenna and the transmission circuit at the second frequency, the first matching circuit being connected in series with the first parallel resonance circuit;
- and
- a second matching circuit configured to perform impedance matching between the transmission antenna and the transmission circuit at the first frequency, the second matching circuit being connected in series with the second parallel resonance circuit, and
- the first parallel resonance circuit and the second parallel resonance circuit are connected in parallel with each other and connected in series with the transmission antenna.
Dependencies are inferred from the claim text.