US 5,400,401 A · System and method for transmitting a plurality of digital services

Abstract

A plurality of digital services are carried in a multiplex data stream to a plurality of remote locations. The multiplex data stream comprises a continuous sequence of frames. Each frame comprises two consecutive fields, and each field comprises a plurality of lines. A first group of the lines in each field defines a transport layer region of that field, and a second group of the lines defines a service data region. Portions of the service data region of each field are allocated to respective ones of the video services in proportion to respective data rates of each service. A multiplex control packet is generated for each field that specifies, for each service, which portion of the service data region is allocated to that service. The multiplex control packet for each field is inserted into the transport layer region of that field along with a plurality of other packets that contain system related information. A multiplex map is generated and inserted in the first line of the transport layer of each field that specifies the number and location of packets within the transport layer. A multiplex map is transmitted with each field, and therefore, the number and location of packets within the transport layer may be dynamically adjusted on a per field basis. Additionally, the service allocation within the service data region of each field may be altered on a per frame basis to support statistical multiplexing.

Claims52

Dependent claims

In a communications system, a method of transmitting a plurality of digital services from an origination point to at least one remote location, said method comprising the steps of:

(a) multiplexing said plurality of digital services in a time-division manner to form a multiplexed data stream, said multiplexed data stream having a format comprising a continuous sequence of fields, the locations of the multiplexed data of said digital services within each field being different for at least one of said fields;
(b) generating, for each field, multiplex location data that specifies the locations of the multiplexed data of said digital services within that field, and inserting the multiplex location data in the multiplex data stream at predetermined positions within that field;
and
(c) transmitting successive fields of the multiplex data stream to at least one remote location, whereby the locations of the multiplexed data of said digital services within each field may vary from field to field and the multiplex location data within each field may be employed at the remote location to determine the locations of the multiplexed data within each field.

1 more element

In a communications system, a method of transmitting a plurality of digital services and a plurality of different types of system related packets from an origination point to at least one remote location, said method comprising the steps of:

(a) multiplexing said digital services and said system related packets in a time-division manner to form a multiplexed data stream having a format comprising a continuous sequence of fields, one portion of each field containing selected ones of said different types of system related packets and remaining portions of each field containing multiplexed data of said plurality of digital services, the locations of the system related packets and the multiplexed data of said digital services within each field being different for at least one of said fields;
(b) for each field, (i) generating multiplex location data that specifies the locations of each type of system related packet contained in that field and specifies the locations of the multiplexed data of said digital services within the field, and (ii) inserting the multiplex location data at pre-determined positions within that field;
and
(c) transmitting successive fields of the multiplex data stream to at least one remote location.

1 more element

A method of demultiplexing a multiplexed data stream received at a remote location, wherein said multiplexed data stream contains multiplexed data of a plurality of digital services and has a format comprising a plurality of fields wherein the locations of the multiplexed data of said digital services within each field may differ from field to field, each field containing multiplex location data that specifies the locations of the multiplexed data of said digital services within that field, said method comprising the steps of:

(a) receiving successive fields of the multiplex data stream at the remote location;
and
(b) for each successive field:
(i) extracting the multiplex location data from the field and identifying, based at least in part upon information contained therein, the locations within that field of the multiplexed data of said digital services;
and
(ii) extracting from the field the data of a selected one of said digital services.

3 more elements

A method of demultiplexing a multiplexed data stream received at a remote location, wherein said multiplexed data stream contains multiplexed data of a plurality of digital services and a plurality of different types of system related packets, and wherein said multiplexed data stream has a format comprising a continuous sequence of fields, one portion of each field containing selected ones of said different types of system related packets and a remaining portion of each field containing multiplexed data of said plurality of digital services, the locations of the system related packets and the multiplexed data of said digital services within each field being different for at least one of said fields, each field containing multiplex location data that specifies the locations of each type of system related packet contained in that field and the locations of the multiplexed data of said digital services with that field, said method of demultiplexing comprising the steps of:

(a) receiving successive fields of the multiplex data stream at the remote location;
and
(b) for each successive field:
(i) extracting the multiplex location data from said field;
and
(ii) locating and extracting the system related packets and the multiplexed data of a selected digital service from the field based upon information contained in the extracted multiplex location data.

3 more elements

An encoder apparatus for multiplexing a plurality of digital services for transmission from an origination point to at least one remote location in a communications system, said encoder apparatus comprising:

multiplexer means for multiplexing said plurality of digital services in a time-division manner to form a multiplexed data stream, said multiplexed data stream having a format comprising a continuous sequence of fields, the locations of the multiplexed data of said digital services within each field being different for at least one of said fields;
means for generating, for each field, multiplex location data that specifies the locations of the multiplexed data of said digital services within that field;
means coupled to the multiplexer means for inserting the multiplex location data of each field in the multiplex data stream at pre-determined positions within each respective field;
and
a transmitter coupled to the multiplexer means for transmitting successive fields of the multiplex data stream to at least one remote location.

2 more elements

An encoder apparatus for multiplexing a plurality of digital services and a plurality of different types of system related packets for transmission from an origination point to at least one remote location in a communications system, said encoder apparatus comprising:

multiplexer means for multiplexing said digital services and said system related packets in a time-division manner to form a multiplexed data stream having a format comprising a continuous sequence of fields, one portion of each field containing selected ones of said different types of system related packets and a remaining portion of each field containing multiplexed data of said plurality of digital services, the locations of the system related packets and the multiplexed data of said digital services within each field being different for at least one of said fields;
means for generating, for each field, multiplex location data that specifies the locations of each type of system related packet contained in that field and that specifies the locations of the multiplexed data of said digital services within that field;
means coupled to the multiplexer means for inserting the multiplex location data for each field in the multiplex data stream at pre-determined positions within the respective fields;
and
a transmitter coupled to the multiplexer means for transmitting successive fields of the multiplex data stream to at least one remote location.

2 more elements

A decoder apparatus for demultiplexing a multiplexed data stream containing multiplexed data of a plurality of digital services and having a format comprising a plurality of fields wherein the locations of the multiplexed data of said digital services within each field may differ from field to field, each field containing multiplex location data located at pre-determined positions therein that specifies the locations of the multiplexed data of said digital services within that field, said decoder apparatus comprising:

a receiver for receiving successive fields of the multiplex data stream;
first means coupled to the receiver for extracting the multiplex location data from a received field and for identifying, based at least in part upon information contained therein, the locations within that field of the multiplexed data of said digital services;
and
second means coupled to the receiver and to the first means for extracting from each field the data of a selected one of said digital services.

1 more element

Dependencies are inferred from the claim text.

System and method for transmitting a plurality of digital services

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System and method for transmitting a plurality of digital services

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Abstract

Claims52