发明名称 |
Spectrum compatible-HDTV data transmission system |
摘要 |
A spectrum compatible HDTV data transmission system includes an adaptive delta modulator for producing 12-bit packets comprising direction and slope components of successive groups of three samples of removed low frequency video siganl. The 12-bit packets are compressed by a lookup table to four-bit output codes prioritized according to the statistical likelihood of occurrence of the 12-bit packet in a typical video signal. The 15 most likely to occur 12-bit packets are mapped to four-bit output codes 1-15 and the remaining 4080 12-bit packets are mapped to a common four-bit linking code. The next 255 most likely to occur of the remaining 4080 12-bit packets are further mapped to eight-bit output codes. All of the remaining 12-bit packets are mapped to the common remaining state of the eight-bit output codes. The compressed output codes are correlated with the constellation states of a quadrature modulator, with the constellation states requiring the least transmission power corresponding to the most likely to occur of the four-bit output codes. The output codes are multiplexed with the high frequency video before application to the quadrature modulator. The output of the modulator is transmitted at RF frequencies.
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申请公布号 |
US5136375(A) |
申请公布日期 |
1992.08.04 |
申请号 |
US19900553822 |
申请日期 |
1990.07.17 |
申请人 |
ZENITH ELECTRONICS CORPORATION |
发明人 |
CITTA, RICHARD W.;MUTZABAUGH, DENNIS M. |
分类号 |
H04N5/44;H04N7/015;H04N7/26 |
主分类号 |
H04N5/44 |
代理机构 |
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地址 |
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