| 摘要 |
PROBLEM TO BE SOLVED: To provide a matching circuit capable of appropriately suppressing the mismatching between the input impedance of an antenna and the output impedance of a transmission circuit.SOLUTION: A mismatching detection unit 20 comprises: a first directional coupling unit 22 which generates a corresponding transmission signal A1 which is the signal corresponding to the transmission signal A from a transmission circuit 2; second directional coupling unit 24 which generates a corresponding reflection signal B1 which is the signal corresponding to the reflection signal B which is the electric signal to be reflected on the transmission circuit 2 from an antenna 4 according to the transmission signal A; and a mismatching detection unit 26 which detects the amplitude ratio and phase difference between the transmission signal A and the reflection signal B on the basis of the corresponding transmission signal A1 and the corresponding reflection signal B1. An operation unit 28 transmits a matching unit control signal D to a matching unit 30 on the basis of the amplitude ratio and phase difference between the transmission signal A and the reflection signal detected by the mismatching detection unit 26. The matching unit 30 changes the signal value of the reflection signal B by changing the impedance on the basis of the matching unit control signal D.SELECTED DRAWING: Figure 1 |
