Radio base station, user terminal and fading frequency estimation method

A fading frequency estimation method for estimating fading frequency in a user terminal that communicates with a radio base station, the fading frequency estimation method comprising the steps in which:

• the radio base station:
• arranges a reference signal, using an arrangement format, in which the reference signal, which is used to estimate fading frequency in the user terminal, is arranged in a relatively high density, in at least part of radio resources allocated for a downlink shared data channel;
• and
• transmits allocation information of the radio resources for the downlink shared data channel to the user terminal;
• and
• the user terminal:
• estimates the fading frequency based on a channel estimation value of the reference signal;
• and
• transmits the estimated fading frequency to the radio base station in response to a transmission request from the radio base station.

A fading frequency estimation method for estimating fading frequency in a radio base station that communicates with a user terminal, the fading frequency estimation method comprising the steps in which:

• the user terminal:
• receives allocation information of radio resources for an uplink shared data channel;
• and
• arranges a reference signal, using an arrangement format, in which the reference signal, which is used to estimate fading frequency in the radio base station, is arranged in a relatively high density, in at least part of the radio resources allocated for the uplink shared data channel;
• and
• the radio base station estimates the fading frequency based on a channel estimation values of the reference signal.