COMMUNICATION SYSTEM, BASE STATION, TERMINAL, AND COMMUNICATION METHOD

摘要

In a communication system of the OFDM method using an adaptive array, it is possible to reduce the probability of instantaneous peak power increase so as to reduce degradation of a signal quality and accurately measure an interference power by a carrier sense measurement. The communication system includes: data creation units (11, 27) which perform data mapping; symbol insertion units (12, 28) which insert a null symbol into a sub-channel having no data if the number of sub-channels containing mapped data is small; and symbol interleave units (13, 29) which perform symbol interleave over the entire user allocation band and insert a known training symbol and a pilot symbol into a predetermined symbol position in the user allocation band. Symbols are arranged so that a signal phase change in the same sub-carrier between a plurality of symbols is continuous and the carrier sense is executed at the symbol position where the signal phase change is continuous.