TV Transmission system for long tow cables
US4268858A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 4, 1977 |
| Grant date | May 19, 1981 |
| Priority date | — |
| Expiry date | Mar 4, 1997 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/102
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An underwater survey system where the existence of a large number of multiplex signals in conjunction with a relatively poor frequency response over a long tow cable, results in a situation where the transmission of a normal 30 frames per second TV picture is impossible. The invention describes a method of transmitting a reduced bandwidth TV system where the signals are modulated on a carrier and the lower sideband used. The large signal loss at the upper frequency is compensated by equalizers, which can result in objectionable interference, when the vehicle is close to the receiving end. A remotely controlled carrier is used to minimize this interference.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.