Kyocera Corporation

Hiroki Fujita

Masahiro Yagi

Nobuaki Takamatsu

Yoshizo Sato

Masaaki Nakata

Takeshi Suzuki

Shinobu Fujimoto

Hiroshi Sakai

Tetsuo Okamoto

Takatoshi Yoshikawa

Yuta Umehara

A wireless roadside device that performs roadside-to-vehicle communication with an in-vehicle communication device in a traffic communication system includes a roadside-to-vehicle communicator that cyclically transmits a roadside-to-vehicle message, and a controller that performs inhibition control to inhibit cyclic transmission of the roadside-to-vehicle message when the roadside-to-vehicle communicator receives no vehicle information message from the in-vehicle communication device.

Wireless roadside device, traffic communication system, and traffic communication method

A base station used in a traffic communication system includes a communicator configured to receive, via wireless communication, information transmitted from a vehicle traveling on a road, and a controller configured to identify, based on the information received by the communicator, a traveling behavior including a travel route of the vehicle on the road. The controller is configured to execute first processing for performing statistical learning or machine learning on a plurality of the traveling behaviors respectively identified for a plurality of the vehicles traveling on the road, and second processing for determining, based on a result of the first processing, whether a traffic obstacle is present on the road and a position of the traffic obstacle on the road.

Base station, roadside device, traffic communication system, traffic management method, and training data generation method

A base stationis installed around a road. The base stationincludes a controllerand a communicator. The controlleris configured to acquire weather condition information indicating a weather condition on the road, and to estimate a risk level of occurrence of a traffic accident on the road based on the weather condition information. The communicatoris configured to transmit, to a vehicleon the road, a warning message including information based on the risk level estimated.

Base station, traffic communication system, and traffic communication method

A roadside device, which performs radio communication with a mobile station on a road, includes: a first communicatoravailable for a first radio communication scheme; a second communicator availablefor a second radio communication scheme different from the first radio communication scheme; and a controller configured to acquire, from the first mobile station via the first communicator, information associated with a first mobile station and distribute the acquired information to a second mobile station via the second communicator

Base station, transport communication system, and method

A radio communication method includes: broadcasting a communication packet including application data regarding to a road and identification indicating a first type of a road corresponding to the application data, by a base station provided around the road. The radio communication method includes receiving the communication packet from the base station, by a mobile station installed on a vehicle. The radio communication method includes specifying a second type of the road on which the vehicle installed the mobile station travels, by the mobile station. The radio communication method includes acquiring the application data included in the received communication packet, when the first type of the road indicated by the identification information included in the received communication packet and the specified second type of the road match.

Radio communication system, base station, mobile station, and radio communication method

A base station allocates at least one of a plurality of wireless channels included in a used frequency hand to a mobile station. The base station includes: a used frequency hand determination unit for determining at least a part of a predetermined frequency band as the used frequency band; a message generation unit for generating a control message including used frequency band information which is placed in a predetermined position and which indicates the determined used frequency hand, and channel allocation information which has a size corresponding to a bandwidth of the used frequency band and which indicates the wireless channel to be allocated to the mobile station; and a modem and a wireless communication unit for transmitting the generated control message to the mobile station.

Wireless communication system, master communication device, slave communication device, and channel allocation information notification method

Provided is, in wireless communication systems such as TD-LTE where there might be difference in frequency band allocated to a mobile station between uplink and downlink, a wireless communication system which is capable of ensuring desired antenna directivity by the mobile station controlling an adaptive array antenna, such a method for controlling a wireless communication system, such a base station, and such a mobile station. The mobile station transmits to the base station a message indicating that the self station includes an adaptive array antenna. Upon receiving the message, the base station assigns a downlink resource block and an uplink resource block following the downlink resource block allocated to the mobile station within the same frequency band. The mobile stationcontrols the adaptive array antenna based on a signal received using the allocated downlink resource block and transmits a signal using the allocated uplink resource block.

Wireless communication system, method for controlling wireless communication system, base station, and mobile station

In a case where, although a radio base station (eNB-) has established an SRS transmission frequency band, a serving radio terminal (UE-) has transmitted, to the radio base station (eNB-), an SRS by use of only a frequency band that is a part of the SRS transmission frequency band, the radio base station (eNB-) allocates a downstream resource block the frequency band of which is included in the SRS transmission frequency band and further the frequency band of which is identical with the frequency band of the SRS received at the latest; then establishes, for the downstream resource block, a transmission weight based on the SRS received at the latest; and then uses the downstream resource block to transmit a radio signal.

Radio base station, radio terminal, and communication control method

An eNB-transmits an RRC Connection Reconfiguration message to UE-to UE-, in which SRS parameters and an application timing parameter are set, the SRS parameters differ for each of the UE-to the UE-and the application timing parameter is common in the UE-to the UE-. The UE-to the UE-receive the RRC Connection Reconfiguration message and recognize the SRS parameters and the application timing parameter set in the message. Furthermore, when an application timing of the SRS parameter arrives, the UE-to the UE-apply the SRS parameter to the SRS and transmit the SRS.

Radio base station, radio terminal, and communication control method for applying a reference signal parameter

If the frequency band of an SRS from a serving radio terminal (UE-) is identical with the frequency band of an SRS from a serving radio terminal (UE-), a radio base station (eNB-) transmits, to one of the serving radio terminals (UE-, UE-), an RRC connection reconfiguration message in which transmission halt request information has been set.

Radio base station and communication control method including a request to stop transmission of a reference signal at a predetermined timing

A wireless base station (eNB-) uses in a differentiated manner, depending on the expected data amount of downlink transmission to the serving wireless terminal UE, the transmission of RRC Connection Reconfiguration messages in which SRS specific transmission request information is set, and the transmission of RRC Connection Reconfiguration messages in which SRS hopping transmission request information is set.

Sounding reference signal to determine antenna weight and frequency bands

The present invention provides a wireless base station (eNB-) that sets a first SRS transmission frequency band as a transmission frequency band for SRS at a first SSF timing and sets the first SRS transmission frequency band as the transmission frequency band for SRS at a second SSF timing, within the time for one frame. In this way, all frequency bands (allocatable frequency bands) for usable downstream resource blocks in wireless communications between the wireless base station (eNB-) and a serving wireless terminal (UE-) are covered by the first SRS transmission frequency band and the second SRS transmission frequency band.

Radio base station and communication control method setting an entire frequency band of a radio resource as a reference signal transmission frequency band within a predetermined period

Disclosed is a wireless base station (eNB-) that sets to each serving wireless terminal (UE) different frequency bandwidths (SRS transmission frequency bandwidths) that are used when said serving wireless terminals (UE) send SRS at a predetermined special sub-frame timing. In addition the wireless base station (eNB-) sends the set SRS transmission frequency bandwidth information to the serving wireless terminals (UE).

Radio base station and communication control method

A transmission path state estimation unit estimates a state of a transmission path to a wireless terminal based on a DRS (Demodulation Reference Signal) included in uplink user data received from the wireless terminal when a re-sending request is received after transmission of an SRS is stopped. A transmission unit forms directivity of a plurality of antennas based on the estimated state of the transmission path and transmits downlink user data.

Wireless base station and wireless communication method

A resource determination unit determines at least a part of an uplink part in a switch subframe as a second resource for a wireless terminal to transmit an SRS and determines at least a part within any uplink subframe as a third resource for the wireless terminal to transmit uplink user data including a DRS for a prescribed period. A transmission path state estimation unit estimates a state of a transmission path to the wireless terminal based on the DRS included in the uplink user data after the third resource is determined. A resource notification unit forms antenna directivity based on the estimated state of the transmission path and transmits a control message for notifying the wireless terminal of the determined second resource.

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Yokohama, Japan

Hiroki Fujita