Patent ID: 7890118

Claim:
A wireless system including a plurality of first wireless base stations, a plurality of second wireless base stations and a positioning server, both said first wireless base stations and said second wireless base stations being operable to perform communication with a wireless terminal via a plurality of communication channels, wherein: said first wireless base stations transmit and receive signals for user data with a first preamble, transmit and receive signals for position detection with a second preamble having a length that is longer than a length of said first preamble, said wireless terminal transmits and receives signals for user data with a third preamble, transmits and receives signals for position detection with a fourth preamble having a length that is longer than a length of said third preamble, and said first wireless base stations and said wireless terminal transmit signals for position detection to said wireless terminal and at least one of said second wireless base stations, at least one of said second wireless base stations receives signals for position detection from said first wireless base stations with the second preamble and from said wireless terminal with the fourth preamble.