A method of controlling communications includes determining whether reception of information from a mobile station is normal, generating a first signal when it is determined to be normal, and generating a second signal when it is determined to be abnormal. When the mobile station is instructed to retransmit information using a first radio resource used in previous transmission, and when it is determined to be abnormal and when the mobile station is instructed to retransmit the information using a second radio resource different from the first radio resource, the method generates the first signal and a third signal including information on the second radio resource, and transmits any one of the first signal, the second signal, and a combination of the first signal and the third signal, the first signal and the second signal and the combination of the first signal and the third signal being generated.