Abstract: Devices and methods to allow a source of noise generated by modulation with a signal inside a device to be easily measured. A measurement device according to an embodiment includes: a transmission unit that applies a first signal formed by a high frequency signal to an object to be measured; a reception unit that receives a second signal formed by a high frequency signal generated from the object to be measured; and a measurement unit that measures the second signal received by the reception unit. The reception unit receives the second signal while the transmission unit applies the first signal.

Abstract: A connection device apparatus including a housing having tubular rectangle shape and a support portion integrally formed with the housing, a shell having a body portion with tubular rectangle shape, wherein the shell is supported by the support portion of the housing, and the body portion of the shell is provided with a first plurality of comb-teeth which project from an end side of an upper face of the body portion, a shield member configured to surround an end portion of the first plurality of comb-teeth of the body portion of the shell, and wherein the shield member is connected with the end portion of the first plurality of comb-teeth and the ground of the printed-circuit board, and a plurality of terminals arranged within the shell and supported by the support portion of the housing.

Abstract: This specification discloses an excellent communication device of a field coupling type that increases field coupling efficiency between electrodes and realizes a small-sized device. This specification also discloses a communication system and an electrode. A communication device 100 includes: a first resonant circuit 121 connected in series to an electrode unit 110 formed with two conductor plates; and a second resonant circuit 122 connected in parallel to the electrode unit 110 and the first resonant circuit 121, which are connected in series. The constant of a resonant circuit is determined so that the voltage V2 to be applied to the electrode unit 110 becomes higher than the voltage V1 to be applied to the electrode unit 110 and the first resonant circuit 121 connected in series. In this manner, a field coupling electrode that has a very high coupling strength at a target frequency is obtained.

Abstract: This specification discloses an excellent communication device of a field coupling type that increases field coupling efficiency between electrodes and realizes a small-sized device. This specification also discloses a communication system and an electrode. A communication device 100 includes: a first resonant circuit 121 connected in series to an electrode unit 110 formed with two conductor plates; and a second resonant circuit 122 connected in parallel to the electrode unit 110 and the first resonant circuit 121, which are connected in series. The constant of a resonant circuit is determined so that the voltage V2 to be applied to the electrode unit 110 becomes higher than the voltage V1 to be applied to the electrode unit 110 and the first resonant circuit 121 connected in series. In this manner, a field coupling electrode that has a very high coupling strength at a target frequency is obtained.