Data Transmission System
Television and video programming are now available by cable systems. However, the difficulty is that telecommunication services are commonly provided through a network of optical fibre cables that extend as far as the basement of a building, and then for signals to be carried to individual users by a twisted-pair cable. While a twisted-pair cable is more than adequate for carrying voice transmissions and simple data transmission, such a cable introduces channel distortion that degrades picture quality.
The novel preemphsis filter system relates to a method for the distribution/transmission of video signal through category 5 twisted pairs for a distance of up to at least 300 meters. The invented method utilized a new channel characterization circuit to determine the magnitude and phase responses of a channel and then uses a preemphasis filter to compensate the channel distortion at the transmitter. The invented system can be used by telecom companies to provide video-on-demand, Internet connection and other interactive multimedia services.
1. A preemphasis filter system has lower bit error rate than an equalizer system since an equalizer would also enhance the noise when trying to compensate a distorted signal
2. A preemphasis filter can be time-shared and hence more cost-effective
3. Cheaper than an equalizer system
4. Better performance
- Private video-on-demand (VOD), interactive multimedia services
- Intranets for hotels, hospitals, shopping centers, recreational centers, large corporations that require high speed data/video distribution up to 300 meters
Patent Number: US6571393B1
Application Number: US199884501A
Inventor: Ko, Tsz Mei | Liou, Ming | Cheung, Kwan Fai | Cheng, Roger | Hu, Bo | Qu, Donghui
Priority Date: 27 May 1998
Priority Number: US6571393B1
Application Date: 27 May 1998
Publication Date: 27 May 2003
IPC Current: H03G000500 | H04N000710 | H04N001700
US Class: 725121 | 333018 | 348192 | 348E0705 | 348E07051 | 348E17003 | 4550631 | 455069 | 725127 | 725149 | 455063 | 4550674 | 4550676
Assignee Applicant: The Hong Kong University of Science & Technology
Title: Data transmission system
Usefulness: Data transmission system
Summary: For distribution of video signal e.g. video-on-demand (VOD) signal, television and video programming, multimedia, also for Internet connection and interactive television, in residential or commercial building.
Novelty: Video signal data transmission system e.g. for video-on-demand, adjusts properties of pre-emphasis filter provided between server and connecter, based on channel distortions, so as to compensate distortions
信息和通信技术/电信
多媒体
27 May 1998
US 6571393
TTC.PA.080
香港
