Patent ID: 6944454

Claim:
A method for expanding cell coverage in a code division multiple access (CDMA) mobile communication system comprising the steps of: a) shifting a preamble access window by advancing transmission time of a transmission signal by a first delay time in order to acquire a first call access signal from a mobile station at a remote distance; and b) delaying a second call access signal from a mobile station at a short distance by a second delay time in order to acquire the second call access signal, wherein the transmission time of the transmission signal is advanced by delaying the transmission signal when being modulated; and wherein the first delay time is substantially equal to the second delay time, and the first delay time is expressed as: first ⁢ ⁢ delay ⁢ ⁢ time ⁡ ( μs ) = Radius ⁡ ( Km ) × 2 3 × 10 5 × 10 6 , where Radius is a length of the expanded radius.