User terminal, radio base station and radio communication method

A radio base station comprising:

• a transmitter that transmits, to a terminal, a downlink control information (DCI) including information regarding at least one of a scheduling of a plurality of PRACH transmission occasions in a time direction and a configuring of a plurality of PRACH transmission resources in a frequency direction;
• and
• a controller that controls the reception of a PRACH, based on a condition, transmitted from the terminal, based on the DCI,
• wherein the condition indicates that a transmitted information specifies at least one occasion of the plurality of PRACH transmission occasions,
• wherein in a case where Listen Before Talk (LBT) indicates that one of the plurality of PRACH transmission occasions fails due to the result of LBT in a time unit, another one of the plurality of PRACH transmission occasions is used for PRACH transmission, and
• wherein the PRACH transmission occurs if a received signal power measured during the time unit is equal to or lower than a predetermined threshold.

A radio communication method comprising:

• transmitting a physical random access channel (PRACH);
• and
• controlling the transmission of the PRACH, based on a condition, by using at least one of a scheduling of a plurality of PRACH transmission occasions in a time direction and a configuring of a plurality of PRACH transmission resources in a frequency direction,
• wherein the condition indicates that a received information specifies at least one occasion of the plurality of PRACH transmission occasions,
• wherein in a case where Listen Before Talk (LBT) indicates that one of the plurality of PRACH transmission occasions fails due to the result of LBT in a time unit, using another one of the plurality of PRACH transmission occasions for PRACH transmission, and
• wherein the PRACH transmission occurs if a received signal power measured during the time unit is equal to or lower than a predetermined threshold.