A receiving device receiving a multi-carrier signal in which a plurality of pilot signals transmitted from a transmitting device are allocated in a direction of a time axis and in a direction of a frequency axis, comprising: a receiving quality information generating means for generating each piece of receiving quality information on each of pilot channels for transmitting each of the plurality of pilot signals; a determining means for determining the number of the pilot channels needed in the multi-carrier signal transmitted from the transmitting device based on each piece of the receiving quality information; and a notifying means for transmitting a signal requesting the determined number of the pilot channels to the transmitting device; wherein the determining means is further configured to determine the necessary number of the pilot channels in the direction of the frequency axis based on each piece of the receiving quality information on neighboring pilot channels which are neighboring in the direction of the frequency axis, and/or to determine the necessary number of the pilot channels in the direction of the time axis based on each piece of the receiving quality information on neighboring pilot channels which are neighboring in the direction of the time axis; wherein the receiving quality information generating means is further configured to obtain an average value of differences in each piece of the receiving quality information between the neighboring pilot channels in the direction of the frequency axis, and/or to obtain an average value of differences in each piece of the receiving quality information between the neighboring pilot channels in the direction of the time axis, and the determining means is further configured to determine the necessary number of the pilot channels in the direction of the frequency axis based on the average value in the direction of the frequency axis, and/or to determine the necessary number of the pilot channels in the direction of the time axis based on the average value in the direction of the time axis; and wherein the determining means is further configured to determine to increase and decrease the necessary number of the pilot channels in the direction of the frequency axis by comparing the average value in the direction of the frequency axis with a predetermined threshold value, and/or to determine to increase and decrease the necessary number of the pilot channels in the direction of the time axis by comparing the average value in the direction of the time axis with a predetermined threshold value. a receiving quality information generating means for generating each piece of receiving quality information on each of pilot channels for transmitting each of the plurality of pilot signals; a determining means for determining the number of the pilot channels needed in the multi-carrier signal transmitted from the transmitting device based on each piece of the receiving quality information; and a notifying means for transmitting a signal requesting the determined number of the pilot channels to the transmitting device; wherein the determining means is further configured to determine the necessary number of the pilot channels in the direction of the frequency axis based on each piece of the receiving quality information on neighboring pilot channels which are neighboring in the direction of the frequency axis, and/or to determine the necessary number of the pilot channels in the direction of the time axis based on each piece of the receiving quality information on neighboring pilot channels which are neighboring in the direction of the time axis; wherein the receiving quality information generating means is further configured to obtain an average value of differences in each piece of the receiving quality information between the neighboring pilot channels in the direction of the frequency axis, and/or to obtain an average value of differences in each piece of the receiving quality information between the neighboring pilot channels in the direction of the time axis, and the determining means is further configured to determine the necessary number of the pilot channels in the direction of the frequency axis based on the average value in the direction of the frequency axis, and/or to determine the necessary number of the pilot channels in the direction of the time axis based on the average value in the direction of the time axis; and wherein the determining means is further configured to determine to increase and decrease the necessary number of the pilot channels in the direction of the frequency axis by comparing the average value in the direction of the frequency axis with a predetermined threshold value, and/or to determine to increase and decrease the necessary number of the pilot channels in the direction of the time axis by comparing the average value in the direction of the time axis with a predetermined threshold value.