A transmitter which communicates with a receiver. The transmitter includes a null subcarrier allocation unit which allocates a null subcarrier based on a priority and a signal. The priority is for allocating a null subcarrier to each subcarrier. The priority is a ranking predetermined with the receiver. The signal is allocated to each subcarrier. The transmitter includes a transmission unit which transmits the signal using the subcarrier allocated by the null subcarrier allocation unit as the null subcarrier to the receiver.