Radio equipment controller, radio control method, radio station, and radio communication system

A radio control method comprising:

• calculating a delay amount by subtracting from a given maximum delay amount an internal delay amount of a radio equipment and a delay amount of a cable, the radio equipment modulating and transmitting orthogonal frequency division multiplexing (OFDM) symbols, and the cable connecting the radio equipment and the radio equipment controller that creates the OFDM symbols;
• detecting a beginning of the OFDM symbols from data that is inputted into a buffer that stores data of the OFDM symbols;
• and
• determining a transmission timing of the OFDM symbols so that the transmission timing of the beginning of the OFDM symbols becomes a timing that is delayed by the calculated delay amount after a reference signal with a specific period, wherein
• the detecting includes comparing data stored in the buffer with data derived from the data stored in the buffer being delayed a specific offset length, and detecting, as the OFDM symbol beginning, data stored in the buffer subsequent to the last data that matches when data that matches is a cyclic prefix (CP) length portion.

A radio station comprising:

• a radio equipment controller that creates orthogonal frequency division multiplexing (OFDM) symbols, and
• a radio equipment that modulates and transmits the OFDM symbols, wherein
• the radio equipment controller includes
• a calculator that calculates a delay amount by subtracting an internal delay amount in the radio equipment and a delay amount of a cable connecting the radio equipment and the radio equipment controller, from a given maximum delay amount;
• a detector that detects a beginning of the OFDM symbols from data that is inputted into a buffer that stores data of the OFDM symbols;
• and
• a delay controller that determines a transmission timing of the OFDM symbols so that the transmission timing of the beginning of the OFDM symbols becomes a timing that is delayed by the calculated delay amount after a reference signal with a specific period, wherein
• the detector compares data stored in the buffer with data derived from the data stored in the buffer being delayed by a specific offset length, and detects, as the OFDM symbol beginning, data stored in the buffer subsequent to the last data that matches when data that matches is a cyclic prefix (CP) length portion.

A radio communication system comprising:

• a radio base station including a radio equipment controller that creates orthogonal frequency division multiplexing (OFDM) symbols and a radio equipment that modulates and transmits the OFDM symbols,
• and a mobile terminal that communicates with the radio base station;
• wherein
• the radio base station comprises:
• a calculator that calculates a delay amount by subtracting an internal delay amount in the radio equipment and a delay amount of a cable connecting the radio equipment and the radio equipment controller, from a given maximum delay amount;
• a detector that detects a beginning of the OFDM symbols from data that is inputted into a buffer that stores data of the OFDM symbols;
• and
• a delay controller that determines a transmission timing of the OFDM symbols so that the transmission timing of the beginning of the OFDM symbols becomes a timing that is delayed by the calculated delay amount after a reference signal with a specific period, wherein
• the detector compares data stored in the buffer with data derived from the data stored in the buffer being delayed by a specific offset length, and detects, as the OFDM symbol beginning, data stored in the buffer subsequent to the last data that matches when data that matches is a cyclic prefix (CP) length portion.