Abstract: A communication system includes a master communication device and a plurality of slave communication devices. The master communication device obtains, for each of the plurality of slave communication devices, multiple communication characteristics during wireless communication. The communication system further includes a storage unit storing multiple reference communication characteristics. The system determines an abnormality in wireless communication between the at least one master communication device and each of the plurality of slave communication devices based on strength of correlation between (a) an overall trend of the obtained multiple communication characteristics and (b) an overall trend of the multiple reference communication characteristics stored in the storage unit.

Abstract: A battery controller is equipped with a primary antenna used in radio communication between itself and battery monitors. Each of the battery monitors is equipped with a secondary antenna used in radio communication between itself and the battery controller. Each of the secondary antennas and/or the primary antenna is configured to selectively have a first antenna directivity that is one of a plurality of directivities whose center axes are different in orientation from each other. The first antenna directivity excludes one of the directivities which causes a degree of quality of radio communication between the primary antenna and a corresponding one of the secondary antennas to be minimized or the lowest among the directivities on a channel used for the radio communication.

Abstract: A battery control device includes a parent-device-side storage unit, a parent-device-side communication unit and an identification unit. The parent-device-side storage unit is configured to store parameters related to communication quality of wireless communication between the battery monitoring devices and the battery control device when batteries, battery monitoring devices and the battery control device are arranged in a predetermined arrangement state in an accommodation section; the parameters are associated respectively with the battery monitoring devices. The parent-device-side communication unit is configured to perform the wireless communication with the battery monitoring devices.

Abstract: A wireless communication system includes an aggregate node and sensor nodes wirelessly communicable with the aggregate node. The sensor nodes each transmit data to the aggregate node in a respective scheduled data transmission cycle whenever in a connected state which enables wireless communication therewith. The sensor nodes each cyclically transmits a connection request for wireless communication to the aggregate node whenever in a disconnected state. Then, the sensor nodes each set a request transmission cycle for transmission of the connection request. As to the request transmission cycle, in a situation of being put in a disconnected state unintentionally, the sensor nodes each shorten the request transmission cycle relative to a cycle used in a situation of being intentionally put in a disconnected state.

Abstract: An antenna is disposed, as a part of a conductor, on a substrate. The antenna includes a main plate providing a ground potential; and a patch portion arranged to face the main plate in Z direction. The substrate has a no-arrange region in which no conductor is arranged as a region between a periphery and the main plate in a plan view. A metal support portion of a case is in contact with the no-arrange region on a bottom surface of the substrate. The metal member is in contact with the no-arrange region on a top surface or on a bottom surface opposite to the top surface in the plate thickness direction of the substrate.

Abstract: A communication system includes a master communication device and a plurality of slave communication devices. The master communication device obtains, for each of the plurality of slave communication devices, multiple communication characteristics during wireless communication. The communication system further includes a storage unit storing multiple reference communication characteristics. The system determines an abnormality in wireless communication between the at least one master communication device and each of the plurality of slave communication devices based on strength of correlation between (a) an overall trend of the obtained multiple communication characteristics and (b) an overall trend of the multiple reference communication characteristics stored in the storage unit.

Abstract: A communication system includes a master communication device and slave communication devices. The master communication device obtains information indicative of communication characteristics. The communication system records a combination of the master communication device and at least one of the slave communication devices having a communication abnormality. The system finalizes an abnormal position where the abnormality is occurring when an abnormality-determined position is consistent with a recorded combination of the master communication device and the at least one of the slave communication devices having a communication abnormality.

Abstract: A wireless communication system is mounted on a mobile body, and includes: a master device; and a slave device that performs a wireless communication with the master device while switching a frequency channel. The master device determines whether the frequency channel is available. The master device reflects a result of frequency channel availability determination in a use of the frequency channel.

Abstract: A wireless communication device includes: a substrate containing a dielectric; a zeroth-order resonance antenna; a high frequency circuit mounted on the substrate and a metal body mounted on the substrate. The zeroth-order resonance antenna includes: a main plate providing a ground potential, a patch portion, a feeder line extending from a feeding point to the patch portion to electrically connect the patch portion and the high frequency circuit, at least a part thereof being arranged on a same surface as the patch portion on the substrate, and a short circuit portion. The metal body has a same potential as the main plate. The metal body has a longer length (greater height) than the patch portion in a Z direction.

Abstract: A wireless communication system includes an aggregate node and sensor nodes wirelessly communicable with the aggregate node. The sensor nodes each transmit data to the aggregate node in a respective scheduled data transmission cycle whenever in a connected state which enables wireless communication therewith. The sensor nodes each cyclically transmits a connection request for wireless communication to the aggregate node whenever in a disconnected state. Then, the sensor nodes each set a request transmission cycle for transmission of the connection request. As to the request transmission cycle, in a situation of being put in a disconnected state unintentionally, the sensor nodes each shorten the request transmission cycle relative to a cycle used in a situation of being intentionally put in a disconnected state.

Abstract: An antenna is disposed, as a part of a conductor, on a substrate. The antenna includes a main plate providing a ground potential; and a patch portion arranged to face the main plate in Z direction. The substrate has a no-arrange region in which no conductor is arranged as a region between a periphery and the main plate in a plan view. A metal support portion of a case is in contact with the no-arrange region on a bottom surface of the substrate. The metal member is in contact with the no-arrange region on a top surface or on a bottom surface opposite to the top surface in the plate thickness direction of the substrate.

Abstract: A wireless communication device includes: a substrate containing a dielectric; a zeroth-order resonance antenna; a high frequency circuit mounted on the substrate and a metal body mounted on the substrate. The zeroth-order resonance antenna includes: a main plate providing a ground potential, a patch portion, a feeder line extending from a feeding point to the patch portion to electrically connect the patch portion and the high frequency circuit, at least a part thereof being arranged on a same surface as the patch portion on the substrate, and a short circuit portion. The metal body has a same potential as the main plate. The metal body has a longer length (greater height) than the patch portion in a Z direction.