Abstract: The disclosure provides a quantum device and a microwave device. The quantum device includes a first partition, a second partition, an upper circuit board, a lower circuit board and a flexible circuit. The second partition is arranged below the first partition. The first partition and the second partition are used to define an ultra-low temperature chamber of the quantum device. The upper circuit board, the lower circuit board and the flexible circuit are arranged in the ultra-low temperature chamber. The upper circuit board is disposed on a lower surface of the first partition. The lower circuit board is disposed on an upper surface of the second partition. The flexible circuit is electrically connected between the upper circuit board and the lower circuit board to provide multiple signal paths for mutual signal transmission between the upper circuit board and the lower circuit board.

Abstract: The disclosure is directed to a radio over fiber (RoF) network node, base station, and communication system. In one of the exemplary embodiments, the disclosure is directed to a radio over fiber (RoF) network node which includes not limited to: a laser source which transmits a first laser beam having a first wavelength; a first Electroabsorption Modulated Laser (EML) which modulates a first electrical signal into a second laser beam that is modulated and has a second wavelength; and a first optical coupler which is coupled to the laser source and the EML and transmits an output laser beam having a first carrier frequency which is determined based on a difference between the first wavelength and the second wavelength.

Abstract: The disclosure is directed to a radio over fiber (RoF) network node, base station, and communication system. In one of the exemplary embodiments, the disclosure is directed to a radio over fiber (RoF) network node which includes not limited to: a laser source which transmits a first laser beam having a first wavelength; a first Electroabsorption Modulated Laser (EML) which modulates a first electrical signal into a second laser beam that is modulated and has a second wavelength; and a first optical coupler which is coupled to the laser source and the EML and transmits an output laser beam having a first carrier frequency which is determined based on a difference between the first wavelength and the second wavelength.