According to an embodiment a user equipment UE transmits uplink control signals using one or more chunks of uplink frequency spectrum that contain a simultaneous uplink shared channel; and for the case where there is no simultaneous uplink shared channel available, the UE transmits uplink control signals using only a single chunk of uplink frequency spectrum. In various embodiments the control signals are ACK/NACK control signals transmitted on an uplink control channel, the uplink shared channel comprises a chunk-specific uplink control channel, and each chunk comprises a component carrier of a LTE-A system. Downlink assignment index bits may be included in a downlink grant to the UE which indicates how many chunks in total are allocated in a current downlink subframe. The UE can also use ACK/NACK control signal bundling over chunks in addition to either or both of chunk- specific ACK/NACK control signals or ACK/NAK control signal multiplexing.