Ntt Docomo, Inc.

Tomoya Ohara

Hiroki Harada

Hideaki Takahashi

Satoshi Nagata

Daiki Takeda

Tooru Uchino

Ryosuke Osawa

Kazuki Takeda

Kazuaki Takeda

Xiaolin Hou

Lihui Wang

Akihito Hanaki

Takayuki Isogawa

Yuki Matsumura

Yuichi Kakishima

Shohei Yoshioka

Huan Wang

Daisuke Murayama

Daisuke Kurita

A user equipment includes a transmission unit that transmits a first message including a random access preamble in a two-step random access procedure, a reception unit that receives one or more second messages for contention resolution in the two-step random access procedure, and a control unit that controls an operation to receive the second messages based on information associated with an identifier of the first message included in the second messages.

User equipment and base station apparatus

A terminal includes a receiving unit configured to receive a parameter related to a DRX (Discontinuous reception) from a base station, and a control unit configured to control an operation of the DRX for each of a plurality of component carriers, based on the parameter and a subcarrier spacing applied to the component carrier.

Terminal and communication method

A terminal including: a control unit configured to determine a position of a PUSCH resource to be used in a first step in a two step random access procedure based on a relative position with respect to a position of a preamble resource; and a transmission unit configured to transmit a message of the first step using the preamble resource and the PUSCH resource.

Terminal, communication system, and communication method in a two-step random access procedure

A terminal includes: a receiving unit configured to receive an indication indicating an active state or an inactive state from a base station for each of one or more search space sets included in a search space set group; and a control unit configured to monitor a search space set for which the indication is an active state, and does not monitor a search space set for which the indication is an inactive state, among the search space sets included in the search space set group.

A user equipment includes a transmitting unit configured to transmit a message in a random access procedure by using a preamble resource and a PUSCH resource, and a control unit configured to start a time window for monitoring a random access response after a resource that is one of the preamble resource and the PUSCH resource whichever ends later in time domain.

User equipment and control method

A user equipment includes a control unit that sets an operation mode of the user equipment to an idle mode; and a transmission unit that transmits, while a time alignment retained by the control unit is valid, information indicating presence of the user equipment on each of transmission resources with a predetermined frequency in a time direction, from among a plurality of transmission resources that is preconfigured for transmitting data in the idle mode and arranged in the time direction, wherein the transmission unit stops transmitting the information indicating the presence of the user equipment in response detecting that the time alignment is invalid.

User equipment, base station and communication method

A terminal includes a receiver that receives an index that specifies configuration information for transmitting a random access preamble; and a controller that configures, when the receiver receives additional information that specifies a time domain resource for transmitting the random access preamble and the index falls within a specific numerical range, the time domain resource specified by the additional information, the time domain resource being configured by replacing a time domain resource for transmitting the random access preamble included in the configuration information specified by the index with the time domain resource specified by the additional information.

Terminal and transmission method

A terminal includes a receiving unit that receives, from a base station, a parameter for a random access procedure; a control unit that determines a time domain location of the PUSCH slot based on a time domain location of a Physical Random Access Channel (RACH) slot, subcarrier spacing of the RACH slot, subcarrier spacing of a Physical Uplink Shared Channel (PUSCH) slot, and the parameter; and a transmitting unit that transmits, at the determined time domain location, the PUSCH to the base station.

In a case of using a different frequency band that is different from a frequency band including one or a plurality of frequency ranges, a terminal applies initial access configurations including a format of an initial access signal, the format being different from that for the frequency band. The terminal transmits the initial access signal via an initial access channel set based on the applied initial access configurations.

Terminal performing initial access

A terminal includes a receiver that receives an index specifying configuration information for transmitting a random access preamble; and a controller that configures, in response to the receiver receiving additional information that specifies a time domain resource for transmitting the random access preamble, the time domain resource specified by the additional information, the time domain resource being configured by replacing a time domain resource for transmitting the random access preamble included in the configuration information specified by the index with the time domain resource specified by the additional information.

A terminal includes a reception unit that receives, from a base station, a first set including a plurality of resources that include at least a synchronization signal and optionally further include a broadcast channel and a second set including a plurality of resources that include at least a synchronization signal added to the first set in a frequency domain and optionally further include a broadcast channel, a control unit that assumes a Quasi co location (QCL) identical to a QCL assumed for the first set when receiving the second set, and a communication unit that executes a random access procedure with the base station based on information included in the resources.

A terminal includes a reception unit that receives, from a base station, a set including a plurality of first resources that include at least a synchronization signal and optionally further include a broadcast channel, a control unit that determines which of the first resources included in the set is to be used based on a reception quality controlled for each of the first resources, and a communication unit that executes a random access procedure with the base station based on information included in the determined first resource.

A terminal includes: a receiver configured to receive, from a base station apparatus, first configuration information indicating an Uplink, a Downlink, or a Flexible area in a radio frame, and second configuration information indicating a random access channel (RACH) resource allocation in the radio frame in a time domain; a processor configured to identify an available RACH resource in the radio frame based on the first configuration information and the second configuration information; and a transmitter configured to transmit a preamble to the base station apparatus using the identified available RACH resource.

User apparatus and base station apparatus

A terminal is disclosed that includes a processor, coupled to a transceiver, that monitors a PDCCH (Physical downlink control channel) candidate in a first search space during a random access procedure. The transceiver receives a random access response or a PDSCH (Physical downlink shared channel) for contention resolution from a base station, based on information included in the PDCCH candidate. The transceiver receives a PDSCH or transmits an uplink signal based on information included in a PDCCH candidate monitored in the first search space, until a second search space of a type other than the first search space is configured after the random access procedure is completed. In other aspects, a base station, a communication method, and an apparatus are also disclosed.

Terminal, base station apparatus, communication method, and apparatus

A terminal includes a receiving unit that receives information indicating mapping relation between transmission occasions for a random access preamble and transmission occasions for a physical uplink shared channel for a MessageA transmission in a two step random access procedure; and a control unit that selects, based on the mapping relation, a transmission occasion for the physical uplink shared channel for the MessageA transmission in the two step random access procedure.

Growing community of inventors

Tokyo, Japan

Tomoya Ohara