Determining and simultaneously using a circuit for a mobile device couple to a base station, the circuit may comprise an identification signal detector for receiving a first identification signal corresponding to a first module and a second identification signal corresponding to a second module in the mobile device. The circuit may comprise a receiver for receiving a plurality of signals from the base station; said plurality of signals is configured to set up communication between the mobile device and the base station. The circuit may comprise a calculator for calculating a plurality of parameters in response to the first identification signal, second identification signal and said plurality of signals received from said base station. The circuit may also comprise a processor for attaching the first and second module to the base station simultaneously in response to a plurality of slots by time multiplexing and the plurality of parameters.