An analog base-band (ABB) chipset of a mobile communication system comprises a memory configured to store a test pattern, a test control unit configured to generate a control signal during a test mode, an ABB unit configured to perform a test operation by receiving the test pattern from the memory in response to the test control signal and to output data of the test pattern to the memory in response to the test control signal, and a path selection circuit configured to form a flow path of the test pattern in the ABB unit in response to the test control signal.