A program that can be loaded into, and executed by, a base station apparatus that performs main normal transmission if a communication-target terminal unit exists in the cell thereof and that can perform cooperative transmission when the communication-target terminal unit exists in another cell, causing the base station apparatus to function as
- a reference signal ID code determining means that determines the ID code of a reference signal specific to the terminal unit;
- a reference signal generating means that generates the reference signal based on the determined ID code, and,
- characterized in that the reference signal generating means generates a reference signal for cooperative transmission to be used when the communication-target terminal unit exists in a cooperative transmission cell such as to be different from the reference signal for main transmission that is used by the base station apparatus for performing main transmission, and
- a transmitting means is caused to transmit the reference signal to the terminal unit.