Patent ID: 7511663

Claim:
A method for transmitting signals in a wireless communication system, in which signals are transmitted from a first communication device to a second communication device, said signals being transmitted in consecutive frames, each frame having a preamble section including preamble information, at least one of said first and said second communication devices having a narrow beam antenna which is configured to steer an antenna beam to different positions, each of said different positions corresponding to one of a number of different transmission paths from said first to said second communication device, the method comprising: transmitting and receiving a first preamble section comprising preamble information enabling the estimation of a channel quality of a current transmission path, while said antenna beam is in a current position corresponding to said current transmission path; steering said beam antenna beam from said current position to a different position corresponding to a candidate transmission path; and transmitting and receiving a second preamble section comprising preamble information enabling the estimation of a channel quality of said candidate transmission path while said antenna beam is in said different position, wherein said first and said second preamble section are transmitted in different frames and the number of transmitted frames comprising a second preamble section in relation to the number of transmitted frames comprising a first preamble section is varied depending on a detected channel ciuality for the current transmission path.