Sheet conveyance device and program for sheet conveyance device

An image forming apparatus, comprising:

• a conveyance path portion along which a sheet can be conveyed past a transfer roller at which an image can be transferred to a surface of the sheet;
• a wireless tag communication device configured to receive response waves from a wireless tag of a sheet in the image forming apparatus;
• and
• a controller configured to:
• detect an ID and a first phase of a first response wave received by the wireless tag communication device from the wireless tag,
• store the first phase in association with the ID in a storage,
• receive a second response wave from the wireless tag and detect the ID and a second phase of the second response wave,
• select the ID which is associated with the first phase in the storage if the first phase is different from the second phase, and
• control the wireless tag communication device to write information to the wireless tag associated with the selected ID.