To provide a facility that enable a receiver without a map display function to display a map using data transmitted by an electronic mail.

A map data read unit 3 reads a map data corresponding to a present geographical position that a current position locator 1 locates and an image processing unit 4 converts the map data into image data. A mail transmitter 8 transmits the converted image data including in the electronic mail through a radio transmitter 7, also transmits the map data of any geographical position registered in a geographical position register 10, including in the electronic mail.