Patent ID: 7633924

Claim:
A communications system comprising: a first transmitting apparatus configured to communicate with a receiving apparatus in a first system using a first communication method; and a second transmitting apparatus configured to perform communication in a second system using a second communication method, said second system having a cell coverage area overlapping a cell coverage area of the first system, wherein the first transmitting apparatus and the second transmitting apparatus share a frequency bandwidth, transmit respective information symbols by using the shared frequency bandwidth, and are initially configured to transmit the respective information symbols using different information symbol lengths with respect to the symbol length used by the other transmitting apparatus, and wherein the first transmitting apparatus comprises: an identifying unit configured to receive control information from the second system and identify a symbol length of a second information symbol transmitted from the second transmitting apparatus based on the received control information; and an adjusting unit configured to adjust a symbol length of a first information symbol transmitted from the first transmitting apparatus, by adding, to the first information symbol, a symbol length adjustment signal corresponding to the difference between the identified symbol length of the second information symbol and the symbol length of the first information symbol transmitted from the first transmitting apparatus.