Abstract: An on-vehicle communication system mounted on a vehicle comprises a first switching device, a second switching device and a third switching device each including a first communication port and a second communication port. The first communication port and the second communication port of the first switching device are respectively connected to the first communication port of the second switching device and the first communication port of the third switching device, and the second communication port of the second switching device and the second communication port of the third switching device are connected to each other. Each of the first switching device, the second switching device and the third switching device measures a reception signal quality for the first communication port of the device itself and a reception signal quality for the second communication port of the device itself.

Abstract: A switching device is a switching device mounted on a vehicle and includes a plurality of communication ports connectable to cables for Ethernet communication, a circuit operated by using power supplied via each of the communication ports, an acquisition unit that acquires a measurement result for noise of the power supplied via each of the communication ports, and a determination unit that performs determination processing for determining whether or not power to be supplied via a corresponding one of the communication ports is to be output to the circuit based on the measurement result for noise acquired by the acquisition unit.

Abstract: Downlink is achieved by point-to-multipoint communication. There is provided a radio communication system 1 that provides information to a mobile terminal 3 via a radio communication device 2 that performs radio communication with the mobile terminal 3. The mobile terminal 3 is capable of receiving first downlink information that has been transmitted by point-to-multipoint radio communication receivable by a plurality of the mobile terminals 3, and capable of receiving second downlink information that has been transmitted by point-to-point communication. The mobile terminal 3 is capable of transmitting uplink information by point-to-point radio communication. The first downlink information and the second downlink information are formed such that information to be used in the mobile terminal 3 is obtained when the mobile terminal 3 performs information processing by using both the first downlink information and the second downlink information.

Abstract: Downlink is achieved by point-to-multipoint communication. There is provided a radio communication system 1 that provides information to a mobile terminal 3 via a radio communication device 2 that performs radio communication with the mobile terminal 3. The mobile terminal 3 is capable of receiving first downlink information that has been transmitted by point-to-multipoint radio communication receivable by a plurality of the mobile terminals 3, and capable of receiving second downlink information that has been transmitted by point-to-point communication. The mobile terminal 3 is capable of transmitting uplink information by point-to-point radio communication. The first downlink information and the second downlink information are formed such that information to be used in the mobile terminal 3 is obtained when the mobile terminal 3 performs information processing by using both the first downlink information and the second downlink information.