(Not applicable)
1. Field of the Invention
The invention relates to switched broadcast systems.
2. Description of the Related Art
Switched broadcast systems are systems in which content is transmitted from content providers to subscribers on an on-demand basis. This down-stream transmission is conducted in accordance with out-of-band (upstream) requests from the subscribers, who select the content using for example a set-top box having a handheld remote control. Because of bandwidth limitations, it is costly and impractical to transmit to each subscriber of a service group all available content or programs. Instead, what has traditionally been done is for network managers to determine which programs are the most popular, and to send these to all subscribers in all service groups. As for the remaining programs, these are switched in groups and forwarded to the subscribers on an on-demand basis. These group allocations are also manually made by the network manager. A major difficulty that arises is how to make these group assignments efficiently and in a timely manner, given the constant changes in content demand based on numerous factors such as time of day, day of week, season, and aberrational events such as natural disasters and other news-intensive activity.
The above issues are addressed by the inventive system and method, which in accordance with one aspect provide an auto-adaptive switched program distribution system for distributing content from a plurality of content providers to one or more subscribers each associated with a service group. The system includes first and second gateway devices communicating over a distribution ring by way of which the content is transmitted, and an auto-adaptive switch receiving at an input thereof the transmitted content from the plurality of content providers. The auto-adaptive switch has a plurality of outputs of which at least one is associated with a first content group which is broadcast to multiple service groups, and of which at least another is associated with a second content group which is forwarded to one or more service groups, the second content group including at least one program selected on an on-demand basis. The first and second content groups are automatically determined by the auto-adaptive switch.
In accordance with another aspect of the invention, there is provided an auto-adaptive switch configured to direct content from one or more content providers to one or more subscribers each associated with a service group. The switch includes a plurality of content inputs through which content is received by the switch and a plurality of content outputs through which content is output by the switch. At least one of the content outputs is associated with a first content group which is broadcast to multiple service groups, and at least another of the content outputs being associated with a second content group which is forwarded to one or more service groups and including at least one program which is selected on an on-demand basis. The switch further includes an analysis module configured to assign a first subset of the content from the one or more content providers to the first content group and a second subset of the content from the one or more content providers to the second content group.
In accordance with another aspect of the invention, there is provided a method for dynamically directing content from one or more content providers to one or more subscribers each associated with a service group. The method includes receiving the content from the one or more content providers, automatically assigning a first subset of the received content to a first output and directing the first subset through the first output to multiple service groups and automatically assigning a second subset of the received content to a second output and directing the second subset through the second output to one of the service groups, the second subset including at least one program selected on an on-demand basis.
Many advantages of the present invention will be apparent to those skilled in the art with a reading of this specification in conjunction with the attached drawings, wherein like reference numerals are applied to like elements, and wherein:
QAM modulators 28 (that is, 28a1, 28a2, 28b1, 28b2, and so forth) are designed to deliver on-demand (switched) programming to each service group. QAM modulators 29 (that is, 291, 292, and so forth), by contrast, are dedicated to broadcast programming. Considering a set of S programs (for example 150) which the system 10 is designed to distribute from master headend 11 to the HFC networks 38 and subscribers, a subset of the S programs, designated P, consists of what has been determined to be the most popular or most requested or watched programs or programs complying with any similar criterion and thus having some preferred status. Broadcast QAM modulators 29 are dedicated to this subset P of most popular programs. Their outputs are transmitted to all of the HFC networks (38a, 38b) so that they reach multiple service groups regardless of subscriber selection. The remaining programs can be classed into a set R containing one or more possibly intersecting sets U which are assigned to on-demand QAM modulators 28a1, 28a2, 28b1, 28b2, and so forth. Outputs of QAM modulators 291, 292 are combined with outputs of QAM modulators 28a1, 28a2 in RF combiner 32a, and with outputs of QAM modulators 28b1, 28b2 in RF combiner 32b. Selections by subscribers 36 are made via for example television remote control terminals (not shown) which transmit the subscriber's selection through the set-top box (STB) (not shown) as OOB (out-of-band) signals directed to auto-adaptive switch 30.
Auto-adaptive switch 30 receives S programming signals at its input, makes P and U subset assignments in accordance with suitable analysis algorithms performed by analysis module 40, and outputs at a first output 42 the designated P programs, and outputs at a plurality of second outputs 44 the designated U programs. Programs P and U are then combined and each set U+P is transmitted to a service group X, Y, Z etc. that is associated with an HFC network 38, such as network 38a or network 38b in
It will be appreciated that program content of subsets P and U is dynamically determined and constantly changes based on analysis algorithms performed in an automated fashion by switch 30, and more particularly, by analysis module 40 of the switch. Refreshing of the program allocation between the subsets P and U can be performed on a regular basis—for instance, hourly, daily, weekly, or monthly, or when no more switched channels are available in any given service group, or on any time schedule that is deemed to be optimal for taking into account factors such as seasonal viewership of television programming, sporting event scheduling, weekday, weekend or holiday usage traffic, and so on. It can alternatively or in addition be performed on demand, based on manager requests from master headend 11 for example, which requests could be used to trigger and/or modify the recalculation algorithms of analysis module 40 of the switch 30.
Let's assume 3 service groups X, Y, Z, served respectively by the group of programs U1+P, U2+P, U3+P. The group S consists of the total number of programs Sn that can be watched by any subscriber on the service groups X Y and Z.
The group of programs P is common to all 3 service groups. The groups of programs U1, U2, U3 consist of the programs that are being watched in each service group, and not already present in the group P.
Let's assume that the group P can deliver Pn number of programs, and the groups U1, U2, U3, Un number of programs.
Based on the above description, it will be understood that in order for the system to be statistically efficient over a traditional broadcast mode of delivery, Pn+Un<<Sn
The analysis module 40 classifies and sorts the Sn programs available to the subscribers by order of popularity across all three service groups X, Y and Z. In other words, for each Sn programs of the group S, the analysis module 40 counts the total number of subscribers watching each program. The analysis module 40 always assigns the maximum possible number of programs Pn to the group P. The Pn number of programs with the highest number of viewers are allocated to the group P, and the remaining watched programs are allocated to the groups U1, U2, and U3. Note that the programs in groups U1, U2 and U3 may be different but not necessarily.
The above are exemplary modes of carrying out the invention and are not intended to be limiting. It will be apparent to those of ordinary skill in the art that modifications thereto can be made without departure from the spirit and scope of the invention as set forth in the following claims.