Compatible EDTV system providing multi-aspect ratio display on EDTV and conventional television receivers

An extended definition television (EDTV) system transmits, receives and displays both EDTV and conventional signals using a NTSC channel bandwidth. The system produces an EDTV broadcast signal having a picture with a 16:9 aspect ratio and at least one adjacent horizontal border to produce an overall image aspect ratio of 4:3. Picture information is also selectively modulated onto the horizontal border. The EDTV broadcast signal is transmitted in a standard television format, and a receiving circuit is provided comprising a display means with a 16:9 aspect ratio, a detector for determining whether an EDTV or other type of signal is being received, and an expansion circuit responsive to the detector means to produce an expanded picture for display. When an EDTV signal is received, it is expanded and filtered vertically and is expanded horizontally and the 16:9 picture is displayed on the 16:9 display. The receiving circuit derives picture information from both the picture portion and the border portion of the EDTV signal. When a conventional television signal is received, it is displayed on the 16:9 display means with at least one vertical border so that the picture has a 4:3 aspect ratio. The EDTV signal is also compatible with and may be received and displayed on standard NTSC receivers as a 16:9 picture with at least one horizontal border.