Abstract: A frequency up-conversion device and a signal transmission system are provided. A frequency up-conversion device includes a first diplexer, a divider, a digital channel stacking circuit, an up-conversion mixer, and a second diplexer. The first diplexer divides a first signal into a second signal and a third signal. The digital channel stacking circuit transforms the second signal to a fourth signal. The up-conversion mixer mixes the fourth signal and an up-conversion oscillating signal to generate a fifth signal. The second diplexer receives the fifth signal and the third signal to generate a sixth signal for output.

Abstract: A frequency up-conversion device and a signal transmission system are provided. A frequency up-conversion device includes a first diplexer, a divider, a digital channel stacking circuit, an up-conversion mixer, and a second diplexer. The first diplexer divides a first signal into a second signal and a third signal. The digital channel stacking circuit transforms the second signal to a fourth signal. The up-conversion mixer mixes the fourth signal and an up-conversion oscillating signal to generate a fifth signal. The second diplexer receives the fifth signal and the third signal to generate a sixth signal for output.

Abstract: A radiowave receiving device including a waveguide, a probe, a circuit, and an impedance matching mechanism. The waveguide has a cavity for conveying radiowave. The probe, disposed in the cavity, converts radiowave conveyed by the waveguide into a circuit signal. The circuit, electrically coupled to the probe, receives the circuit signal. The impedance matching mechanism provides the waveguide with an impedance match with respect to the circuit. Affixed to the waveguide, the impedance matching mechanism includes a tuning element in a spatial position.