Patent ID: 7688844

Claim:
A data transmission-reception system comprising a base station and a plurality of terminals connected to the base station, respectively, wherein: each of the terminals receives data from the base station upon having acquired priority from the base station during an indication signal interval, which is a period of time starting from when the terminals simultaneously receive an indication signal until the terminals receive a next indication signal, said terminals waiting in standby mode when having failed to acquire priority; and each terminal sends a request signal to the base station after a waiting time has passed from when that terminal has received the indication signal, said waiting time having a length that is a function of the indication signal interval and of a random number generating function, wherein said waiting time constitutes a random time, unique to each terminal, that has passed from when that terminal received the indication signal, and wherein the random time is represented by expression (2): Wait=( Tb−Tb 2)* RND ( ) (2) where Wait indicates a period of time from when the terminal finishes the receiving process of the indication signal until the terminal sends the request signal, Tb indicates the indication signal interval, Tb 2 indicates a period of time from when the terminal starts the receiving process of the indication signal until the terminal finishes the process, and RND( ) indicates a function for producing the random number no less than 0 and less than 1.