Patent ID: 8537756

Claim:
A radio base station, comprising: a Back-off Indicator transmission unit configured to transmit a Back-off Indicator notifying a Back-off value when a usage situation of a random access preamble satisfies a predetermined condition, in a random access procedure, wherein the Back-off value is a value relating to a timing of transmitting the random access preamble in a mobile station, the Back-off Indicator transmission unit is configured to increase a Back-off value to be notified, when a total number of random access preambles received from the mobile station within all the measurement periods of a continuous first predetermined number exceeds a first threshold value, and the Back-off Indicator transmission unit is configured to decrease the Back-off value to be notified, when a total number of random access preambles received from the mobile station within all the measurement periods of a continuous second predetermined number is equal to or less than a second threshold value.