| 摘要 |
<p>In a digital TV broadcast system, an embedded multiresolution scheme implementing joint source/channel coding is employed to offer at least relatively fine (317) and relatively coarse resolution (311) services. The relatively fine resolution service is intended for receivers within a first radius (Rf) of a TV signal transmitter and the relatively coarse resolution service is intended for receivers between the first radius and a second, longer radius (Rc) thereof. Video signals broadcast from the transmitter represent individual signal points which are selected from a signal constellation. The latter comprises signal-point groups each including a multiplicity of the signal points. The selected signal points represent video images in the relatively fine resolution, while the signal-point groups from which the selected signal points originate represent the relatively coarse version of the images.</p> |
