| 摘要 |
<p>PURPOSE: To obtain high noise with standing by providing error protection with differing levels to data elements of different classes generated in a source coding step. CONSTITUTION: A video signal source 101 generates an analog video signal. A coder 104 generates a digital signal, whose data element part is more important than the remaining parts. (m+k) sets of information bits are generated at N sets of signaling intervals, and each symbol interval is set to NT seconds. In a two-dimensional arrangement (N=1), a relation of signaling interval = symbol interval holds. On lines 105, 106, m-bits and k-bits per symbol interval appear and the m-bit information is more important than the k-bit information. Scramblers 110, 111 are used to apply serial - parallel conversion to the bits. Then channels coders 114, 115 generate respectively extended r, p bit-groups (r>m, p>k). Bit values are used to identify a specific channel symbol, and an array mapper 131 provides an output of complex planar coordinates. The resulting signal is broadcasted via a pass-band forming device 141 and a TV modulator 151.</p> |
