Interactive video distribution systems – Video distribution system with upstream communication – Telephony via television distribution network
Reexamination Certificate
1999-08-23
2003-07-15
Srivastava, Vivek (Department: 2611)
Interactive video distribution systems
Video distribution system with upstream communication
Telephony via television distribution network
C725S126000, C725S127000, C455S003050, C455S465000
Reexamination Certificate
active
06594827
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a method and an arrangement for radio telecommunication such as telephony, video, audio and/or high rate data and interactive data communication via a cable television network.
BACKGROUND OF THE INVENTION
Telecommunication services are, for the greater part, bounded to dedicated networks. Speech communication is mainly provided by the Public Switch Telephony Network (PSTN). Video and audio communication is handled by Cable TeleVision (CaTV) networks, and high rate data communication is exchanged over distinct data networks, for example. This results, at the users' site, in as many as access provisions as the number of networks of which a user requires services.
With the increase of telecommunication services applied by a user, a trend to integration or convergence of services can be envisaged. Computer Integrated Telephony (CIT) is an example of the integration of telephony and data services, where video conferencing is the result of the integration of telephony and video communications. Service integration at the operators' site will inevitably lead to integrated workstations for video, telephony, data communications etc. at the users' premises.
In a next step, integration at the network level will take place for which standards like Asynchronous Transfer Mode (ATM) are currently under construction. Internet can be regarded as a first introduction of an integrated or converged network with which from an integrated (multi-media) workstation over an integrated network (Internet) a number of the above distinct services are available. However, it is yet still not clear at which point in time a final integrated network will be available to the majority of telecommunication users.
In the meantime there is a need for a cost effective and quickly to implement solution to provide the best possible integration of telecommunication services on existing networks.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a solution for an integral provision of telecommunication services such as speech or telephony, video, audio, high rate data and interactive data communications.
It is a further object of the present invention to provide an integrated services network terminal unit for use at the subscriber or user premises.
According to the present invention there is provided an arrangement for integrated telecommunication via a Cable TeleVision (CaTV) network in a first or downstream direction from a first or head-end section to second or subscriber sections and in a second or upstream direction from the second or subscriber sections to the first or head-end section, through intermediate trunk, distribution, district, feeder and drop sections, intermediate trunk units connecting the trunk and distribution sections, and distribution and/or district centers connecting the distribution and district sections, and first communication means operative through the CaTV network at a low-end frequency sub-band thereof in accordance with the Digital Enhanced Cordless Telecommunications (DECT) standard, characterized in that the first communication means comprise a plurality of radio access units arranged at the distribution and/or district centers for communication with the subscriber sections through the district, feeder and drop sections of the CaTV network, and wherein the subscriber sections comprise Network Terminal Unit (NTU) means arranged for up-converting to the DECT standard frequency band of the low-end frequency sub-band DECT signals for radio transmission by the NTU means to provide wireless radio communication at the subscriber sections, and for down-converting to DECT signals for transmission at the low-end frequency sub-band in the CaTV network of signals at-the DECT standard frequency band received by the NTU means from wireless radio communication at the subscriber sections.
A typical CaTV network comprises a so-called head-end station equipped with receiver means for receiving signals transmitted by terrestrial satellite transmitters and other communication service providers. The received signals are frequency converted and transmitted by coaxial and/or optical cable via a trunk network and various distribution or district sections and intermediate trunk and distribution and/or district centers to individual CaTV subscriber terminals in the subscriber's homes. The trunk network serves to bridge relatively long distances between a head-end station and the various district sections. From the district sections a drop section serves the subscriber terminals through feeder cables and intermediate tap and amplifier units.
International patent application WO 95/34168 and European patent application 0,695,092 disclose simplified versions of CaTV and coax/fiber cable networks, wherein radio and TV signals and control and telephone data are transmitted from the head-end section to the individual subscribers. Downstream and upstream duplex channels occupy different frequency bands of the network, including the low-end CaTV frequency sub-band.
From a network reliability point of view, in case of a power supply failure, two-way communication (i.e. in the up-downstream directions) at the distribution, district, feeder and drop sections is only readily possible in the low-end CaTV frequency sub-band. However, this sub-band is susceptible for noise and other interferences.
Digital Enhanced Cordless Telecommunications (DECT) is a low power, high capacity Multi Carrier/Time Division Multiple Access/Time Division Duplex (MC/TDMA/TDD) digital radio access technique, providing ten radio carriers, each divided into 24 time-slots which serve 12 duplex 32 kb/s communication channels, called a frame. The 120 communication channels are continuously adaptively selected. A communication channel, when occupied, is individual to a radio link connection between a radio access station an a particular remote telecommunication unit, such as a cordless radio telephone. This type of access technique is known as Continuous Dynamic Channel Allocation (CDCA). The DECT protocol provides data exchange at rates of 32 kb/s or less up to 552 kb/s or more.
An elaborated discussion on DECT can be found in a paper by D. Åkerberg, “Novel Radio Access Principles Useful for the Third Generation Mobile Radio Systems”, The Third IEEE International Symposium on Personal, Indoor and Mobile Radio Communication, Boston Massachusetts, Oct. 19-21, 1992, which paper is included here by reference.
The present invention is based on the insight that by providing the radio access units at the distribution and/or district centers, to each distribution or district section connecting to a distribution and/or district center the full 120 DECT communication channels are available. This different from radio access units installed at the head-end, which allows only 120 channels per CaTV network.
Those skilled in the art will appreciate that, instead of installing the radio access unit at the distribution and/or district centers, installation at the trunk units is also feasible, this dependent on the capacity required.
With the arrangement according to the invention, at the subscriber sections, wireless radio communication is provided, wherein subscribers having a mobile radio terminal can communicate in their neighbourhood via a connection with their own NTU and/or a neighbouring NTU. In case of NTU's connected to the same radio network, no complex roaming or handovers are required.
The NTU's preferably comprise DECT repeater units, which may connect over air to Fixed Access Units (FAU) in the home. These FAU may be provided with identity and access rights, such that the NTU's can be relatively ill equipped, merely serving as a conversion means, and NTU's at low costs can be provided.
The present invention further combines the advantages of the existing CaTV networks, i.e. high rate data capacity in downstream direction and a relatively low data rate capacity in the upstream direction by an arrangement further comprising second
Srivastava Vivek
Telefonaktiebolaget LM Ericsson (publ)
LandOfFree
Method and an arrangement for integrated radio... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and an arrangement for integrated radio..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and an arrangement for integrated radio... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3064667