Abstract: Method for transmitting a high-frequency signal by a coupling effect includes receiving a high-frequency signal by a high-frequency circuit and coupling the high-frequency signal to a coupling circuit by the coupling effect to output a high-frequency coupled signal, and adjusting a filter between the coupling circuit and the high-frequency circuit formed by the coupling effect for adjusting transmission frequency of the high-frequency coupled signal; upon when the high-frequency circuit includes a high-frequency metal probe, the coupling circuit comprises a coupling transmission wire. Meanwhile, upon when the high-frequency circuit includes the coupling transmission wire, the coupling circuit includes the high-frequency metal probe.

Abstract: The mini multilayer band-pass filter for balanced to unbalanced signal transformation includes a multilayer substrate and multiple coupling transmission lines. The multiple coupling transmission lines can be formed on one layer of the multilayer substrate or respectively formed on the corresponding layers. Every two of the coupling transmission lines are coupled in order to form a band-pass filter. The first coupling transmission line is configured with an unbalanced input terminal and the last coupling transmission line is configured with two balanced output terminals. With this configuration, a conventional balanced to unbalanced transformer is not necessary to be configured between the band-pass filter and the post circuit. Hence a volume of the circuit can be reduced, and also a loss of the signal transformation can be reduced. Further, a noise of a coupling effect generated between the filter and the balanced to unbalanced transformer can be avoided.