| 摘要 |
A television communications system enhances the video signal-to-noise ratio by delaying video intelligence over an interval (as by loading the video into a store therefor), while obtaining a measure of its average value and dynamic range. At the transmitter, the video is then read out from memory, has its average value diluted and is amplified before transmission to approach the channel amplitude capacity. At the receiver, the communicated average value and dynamic range signals are utilized to restore the average value to the received wave-and to appropriately reduce its relative amplitude. The concomitant channel amplitude reduction, with offsetting amplitude enhancement at the transmitter, improves the composite channel transmission ratio.
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