U.S. patent application number 09/875476 was filed with the patent office on 2001-10-04 for television distribution system for signal substitution.
This patent application is currently assigned to Information Resources, Inc.. Invention is credited to Cowan, Thomas M., Thomas, Scott J..
Application Number | 20010027564 09/875476 |
Document ID | / |
Family ID | 24786808 |
Filed Date | 2001-10-04 |
United States Patent
Application |
20010027564 |
Kind Code |
A1 |
Cowan, Thomas M. ; et
al. |
October 4, 2001 |
Television distribution system for signal substitution
Abstract
A cable television distribution system in which the head end
substitutes different channels for a plurality of separated
geographic zones. The head end creates a plurality of channel
spectrums and transmits the spectrums on distribution trunks such
that a different spectrum may be present on each distribution
trunk. The spectrums on the distribution trunks are connected to
zones of the viewer community which have been selected for market
research purposes on the basis of demographics.
Inventors: |
Cowan, Thomas M.; (Dundee,
IL) ; Thomas, Scott J.; (Glenview, IL) |
Correspondence
Address: |
FITCH EVEN TABIN AND FLANNERY
120 SOUTH LA SALLE STREET
SUITE 1600
CHICAGO
IL
606033406
|
Assignee: |
Information Resources, Inc.
|
Family ID: |
24786808 |
Appl. No.: |
09/875476 |
Filed: |
June 6, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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09875476 |
Jun 6, 2001 |
|
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08693953 |
Aug 7, 1996 |
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Current U.S.
Class: |
725/146 ;
348/E7.049; 725/147; 725/32 |
Current CPC
Class: |
H04H 60/33 20130101;
H04N 7/10 20130101; H04H 20/103 20130101; H04H 20/78 20130101; H04H
60/66 20130101; H04H 60/63 20130101 |
Class at
Publication: |
725/146 ;
725/147; 725/32 |
International
Class: |
H04N 007/10 |
Claims
What is claimed is:
1. A television distribution system for delivering a plurality of
channel signals in separated TV channels to a plurality of cable
television subscribers in a geographic area comprises, a cable
distribution head end comprising: a plurality of normal channel
signal sources for producing normal TV channel signals to be
delivered to subscribers; a source of a substitute channel signal
to be substituted for at least one normal channel signal; signal
distribution circuitry for receiving the normal channel signals and
the substitute channel signal and for combining the received
channel signals into a spectrum of channels on a plurality of
distribution trunks, the spectrum of channels on less than all of
the plurality of distribution trunks including the substitute
channel signal; and means for generating a plurality of
substantially identical copies of the spectrum of channels of each
distribution trunk and the distribution system comprises: means for
connecting the substantially identical copies of the channel
spectrum of each distribution trunk to different substantially
contiguous zones of the geographic area.
2. The television distribution system of claim 1 wherein the means
for connecting connects the spectrum of channel signals from one of
the distribution trunks to zones of the community separated from
one another by zones connected to others of the distribution trunks
and selected to demographically represent the community for market
research purposes.
3. A television distribution system in accordance with claim 1
wherein the zones connected to at least one distribution trunk are
selected to demographically represent the community for market
research purposes.
4. A television distribution system in accordance with claim 1
wherein a portion of the subscribers are market research panelists
and each zone includes a plurality of panelists.
5. A television distribution system in accordance with claim 1
wherein the connecting means comprises fiber optic means for
connecting the substantially identical copies of the channel
spectrum of each distribution trunk to different ones of the
zones.
6. A television distribution system in accordance with claim 1
comprising a plurality of first signal combiners equal in number to
the number of distribution trunks each first signal combiner
receiving as inputs first channel modulated normal signals for
which no signal substitution is performed and second channel
modulated signals including normal signals and at least one
substitute signal.
7. A television distribution system in accordance with claim 6
wherein the channels of the first channel modulated signals are
distinct from the second channel modulated signals.
8. A television distribution system in accordance with claim 7
comprising: a video switch apparatus for receiving as inputs,
normal channel signals and substitute channel signals and for
selectively connecting the input signals to a plurality of output
ports of the video switch; and circuitry for combining the signals
at the output ports into a plurality of cable television channel
spectrums equal to the number of distribution trunks.
9. A television distribution system in accordance with claim 8
comprising a plurality of channel modulators each connected to an
output of the video switch, the channel modulators comprising a
number of modulators equal to the number of distribution trunks for
each channel of the second channel modulated signals.
10. A television distribution system in accordance with claim 1
comprising: a video switch apparatus for receiving as inputs,
normal channel signals and substitute channel signals and for
selectively connecting the input signals to a plurality of output
ports of the video switch; and circuitry for combining the signals
at the output ports into a plurality of cable television channel
spectrums equal to the number of distribution trunks.
11. A television distribution system in accordance with claim 10
comprising a plurality of channel modulators each connected to an
output of the video switch.
12. A television distribution system in accordance with claim 1
comprising: a plurality of first signal conductors each for
conveying a single channel modulated normal television signal; at
least one second signal conductor for conveying a single channel
modulated substituted television signal; a switched combiner means
connected to receive signals from the first signal conductors and
the second signal conductor for selectively connecting signals from
predefined ones of the first and second signal conductors to the
distribution trunks.
13. A television distribution system in accordance with claim 12
wherein the switched combiner unit comprises a switched combiner
for providing signals to each of the distribution trunks.
14. A television distribution system in accordance with claim 13
wherein each switched combiner comprises a plurality of rf
switches, one rf switch for each of the first signal conductors and
the second signal conductor.
15. A television distribution system in accordance with claim 14
comprising a video switch for selectively connecting substitute
channel signals and normal channel signals onto the first signal
and the second signal conductors.
16. A television distribution system in accordance with claim 14
comprising video switch means for selectively connecting substitute
signal sources to the second signal conductor modulated to a
predetermined channel.
17. A television distribution system in accordance with claim 15
comprising a frequency agile modulator connected to an output port
of the video switch for modulating substitute signals to a
predetermined channel.
18. A television distribution system in accordance with claim 16
comprising means for demodulating selected ones of the normal
channel signals and means for connecting resulting demodulated
signals as inputs to the video switch.
19. A panelist response scanning system comprising a plurality of
product scanning units for location at respective stores, a
targetable television system serving a community of people, a
plurality of panelist identification means for identifying
respective panelists, and a market research computer system for
coupling to said product scanning units, said targetable television
system including head end means, a signal distribution arrangement
and a plurality of television receivers, said head end means
including means for transmitting normal television program signals
and substitute television program signals on a plurality of
distribution trunks connected by the signal distribution
arrangement to said plurality of television receivers, each
television receiver being connected to one of the distribution
trunks preselected so that a plurality of receivers connected to at
least one of the distribution trunks demographically represents the
community for market research purposes, the head end including
means for selectively substituting substitute program signals in
lieu of normal television program signals for transmission of a
substitute program on one of the distribution trunks to the
plurality of the television receivers connected thereto, each of
said respective stores having means for receiving panelist
identification information corresponding to a said panelist
identification means and for receiving product identification
corresponding to said products to produce transaction response
signals including panelist identification signals and product
identification signals respectively identifying the panelists and
the products upon the purchase of products at the store, whereby
the system is closed between the targetable television system and
the product scanning units by the acts of the respective panelists
in viewing the programs presented on the respective television
receivers and presenting their corresponding panelist
identification to one of the respective stores upon making the
purchase of a product, said market research computer system
including means for identifying the particular panelist identifying
information associated with each of the distribution trunks and
responding to said transaction response signals to provide an
indication of panelist behavior in response to said normal and
substitute programs.
20. A panelist response scanning system in accordance with claim 19
comprising controller apparatus for controlling signal substitution
on the distribution trunks and for identifying such substitution to
the market research computer system.
21. A panelist response scanning system in accordance with claim 19
wherein the panelists are distributed throughout a viewer community
and the distribution means comprise means for splitting the signals
on each distribution trunk into a plurality of substantially
identical copies and for conveying the signal copies by fiber optic
means to demographically determined groups of panelists.
22. A panelist response system comprising a targetable television
system serving a community of people, a plurality of panelist
identifications for identifying respective panelists, means for
collecting panelist purchase information, and a market research
computer system, said targetable television system including head
end means, a signal distribution arrangement and a plurality of
television receivers, said head end means including means for
transmitting normal television program signals and substitute
television program signals on a plurality of distribution trunks
connected by the signal distribution arrangement to said plurality
of television receivers, each television receiver being connected
to one of the distribution trunks preselected so that a plurality
of receivers connected to at least one of the distribution trunks
demographically represents the community for market research
purposes, the head end including means for selectively substituting
substitute program signals in lieu of normal television program
signals for transmission of a substitute program on one of the
distribution trunks to the plurality of the television receivers
connected thereto, the means for collecting panelist purchase
information having means for receiving panelist identification
information and for receiving product identification corresponding
to products purchased by the panelist to produce transaction
response signals including panelist identification signals and
product identification signals respectively identifying the
panelists and the products upon the purchase of products, whereby
the system is closed between the targetable television system and
the panelist purchase information by the acts of the respective
panelists in viewing the programs presented on the respective
television receivers and providing their corresponding panelist
identification and purchased product information after making the
purchase of a product, said market research computer system
including means for identifying the particular panelist identifying
information associated with each of the distribution trunks and
responding to said transaction response signals to provide an
indication of panelist behavior in response to said normal and
substitute programs.
23. A panelist response scanning system in accordance with claim 22
comprising controller apparatus for controlling signal substitution
on the distribution trunks and for identifying such substitution to
the market research computer system.
24. A panelist response scanning system in accordance with claim 22
wherein the panelists are distributed throughout a viewer community
and the distribution means comprise means for splitting the signals
on each distribution trunk into a plurality of substantially
identical copies and for conveying the signal copies to
demographically determined groups of panelists.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates generally to the accumulation of
panelist response information and more particularly to the
presentation of selected information to viewers of targeted
television programming and the accumulation of responses from those
viewers.
[0002] Conventional market research has involved subjecting
selected groups of consumers to particular promotional material and
observing their responses. There have, however, been difficulties
peculiar to the exposing of the selected group to particular
promotional material as well as problems peculiar to measuring
their responses. A particular problem is that the method of
exposure of the selected group to the promotional material or the
collection of the responses may skew the results; that is, the
testing itself may influence the results independently of the
material being tested. More particularly, in respect to the
dissemination of television advertisements, if the panelists know
they are receiving special promotional material, they may react
differently than were they to believe they are receiving normal
promotional material. Further, the participating panelists must be
divided into a control group and a test group receiving alternative
material, and it is important that these groups be split so that
the control and test groups are matched on relevant statistics.
[0003] In respect to television advertising, one approach has been
to use cable television with a split cable as illustrated by U.S.
Pat. No. 3,366,731, issued Jan. 30, 1968 to Edward Wallerstein for
Television Distribution System Permitting Program Substitution for
Selected Viewers. In such a split cable system two cables
originating from a single transmitting source go out in different
directions. One advertisement is inserted on one cable and another
advertisement on another cable. A problem that has developed with
this is that the split of the cable produces control and test
groups that are not properly matched for market testing. This is,
the two cables are directed to different neighborhoods at the whim
of the cable television company, whereas the needs of market
research are more particular. It has been known to provide two
cables side by side, so that both cables serve the same
neighborhoods and are, therefore, likely to provide a better match
of control groups to test groups. However, even here there is a
problem that once the cables are laid the cables themselves select
the groups; that is the television viewers are either on cable A or
on cable B and do not admit of special selection to meet the needs
of a particular market test.
[0004] Another television market research system is shown in U.S.
Pat. No. 4,331,973 issued May 25, 1982 to Eskin et al. With the
Eskin et al. system, a substantially identical spectrum of
television channels is provided to all potential viewers. Some
channels of the spectrum are used to convey possible substitute
signals which are not accessible to most viewers. The panelists of
the system are given uniquely addressable panelist receiving
stations. When panelists are to receive substitute signals, the
unique addresses of their respective receiving stations are sent
out to control the receiving stations to tune to the substitute
signals in place of the normal signals that others will watch.
[0005] The Eskin et al. system allows a different combination of
panelists to be selected for each program substitution and has
provided valuable marketing information. The system, however,
requires great expense in providing and maintaining sophisticated
receiving stations in each panelist household. Also, panelists at
times resist the requirement for such receiving stations in
addition to their VCRs and cable television distribution and
decoder boxes which already connect to their televisions.
[0006] A need exists for a market research signal substitution
system which accurately represents the demographics of the
community being served and which avoids the problems, costs and
user resistance of an individually addressed arrangement.
SUMMARY OF THE INVENTION
[0007] In accordance with the present invention, the target
community is divided into a significant plurality of zones of
coverage. In the disclosed exemplary embodiment the number of zones
is 24. The cable head end produces a small plurality of
distribution trunks conveying normal and substitute channel signals
in a cable television distribution spectrum. Each distribution
trunk is split into a plurality of cable television signal feeds
which convey substantially identical signals to their source
distribution trunk. Each zone receives a cable television feed
signal from the cable television head end, which feed signal is
distributed to the viewer households of its respective zone. The
market research firm, prior to connection of feed signals to the
zones, determines from information provided by volunteer panelists,
which combination of zones throughout the community will
demographically reflect the community as a whole or reflect a
desirable attribute of the community. Based on such a determination
the zones are selected and connected by cable signal feeds to one
of the distribution trunks of the cable head end. The cable
television head end equipment, in conjunction with equipment
provided by the market research firm, from time to time produces at
least one distribution trunk television signal spectrum having at
least one substitute channel signal and at least one distribution
trunk television signal spectrum having channel signals not
including the substitute channel signal. Based on the predetermined
connection of distribution trunks to zones via the signal feeds, a
normal spectrum is distributed to some zones while a substituted
spectrum may be delivered to other zones. A market research
computer system stores the associations of panelists with the
particular distribution trunks from which each panelist receives
signals and analyzes panelists' shopping behavior based on the
signals presented to panelists' zones.
[0008] Each panelist in the study is assigned a panelist
identification which may be in the form of a panelist identity
card. When a panelist purchases goods, the panelist identification
is associated with the information identifying the goods purchased
and forwarded to a market research computer system. The market
research firm collects the associated panelist-purchased goods
information in the market research computer system which has
previously been informed of which panelists are served by which
zones and which zones have been provided a television spectrum
signal feed including normal and substitute channel spectrums.
Marketing information can then be generated based on the purchases
of panelists which did and did not receive the substitute channel
programming.
[0009] The panelist responses may be obtained without any conscious
action by the panelists. More particularly, in one embodiment all
the panelists need do is provide initial demographic data and to
identify themselves at the time of purchase of products. Otherwise
they act entirely in accordance with their usual practices. Such
identification might occur, for example, when the panelist uses his
or her credit card for the purchase. More particularly, for grocery
products at least, universal product coding (UPC) has become
common. In accordance with the embodiment of the present invention,
each panelist is provided with a panelist identification card
having a scannable identification thereon which is recorded in a
market research computer system to correspond with the particular
cable signal feed and thus which programming the panelist has
reviewed. The identification card is presented to the cooperating
retail stores where he or she shops, where the card is scanned by a
UPC product scanner along with the scanning of purchased products.
The work load of the panelist is reduced merely to presenting his
identification card. Data capture is electronic and automatic, both
for the product and for the panelist identification. The panelist
never needs to record anything. All data are recorded by the UPC
scanner. The information obtained by the scanner is transmitted by
the retail store to a market research computer system for
association and correlation of the data with the advertisements
sent out to the respective panelists. That is, the signals
transmitted to the respective panelists are identified as the
signals sent out by the cable television head end, and the
responses of the respective panelists are noted by the scanning
units of retail stores and transmitted back to the market research
computer for association and correlation.
[0010] For best association and correlation it is helpful to have
an area blanketed with UPC scanners connected to the system. For
example, if all of the grocery outlets, or substantially all, in a
given geographical area near the panelists are provided with UPC
scanners connected to the market research computer, substantially
all grocery products purchased by the respective panelists are
accounted for. In general, the retailers have substantially no
adjustment to make beyond normal scanning, except for scanning
panelist identification cards.
[0011] A second embodiment of panelist purchase data collection may
also be employed. In the second embodiment, the panelists regularly
report to the marketing research computer system their panelist
identification and data regarding the purchases they have made. For
example, a panelist may be provided with a home UPC scanner which
is used to record recent purchases. The purchase information and
the panelist identity are stored in the home UPC scanner and
transmitted to the market research computer system where they can
be analyzed in the same manner as the retail store collected data.
Many possible ways of data collection may be employed with the
present system provided that the panelist identity and the products
purchased are matched before market research analysis.
[0012] It is an object of the present invention to provide panelist
response scanning by the combination of a targetable television
system for directing specific messages to groups of panelists in
zones of the community, a plurality of panelist identification
means for identifying respective panelists, data collection
arrangements for identifying the products purchased by respective
panelists, and market research computer system for receiving the
information from the plurality of product data collection
arrangements to provide such automatic indication of panelist
behavior.
[0013] The system of the present invention provides results drawn
from selections of panelists in the community as a whole and does
not merely represent an unscientifically selected one-half of the
community as does the Wallerstein arrangement and does not require
the expense and complications of the per-panelist-directed system
of Eskin et al.
[0014] In the present discussion, the term "panelist" is used to
represent the individuals in a particular household. The term
"normal" is used herein to signify the messages, signals or
programs provided by the operation of the television system in the
absence of the substitution provided by the present invention. It
thus may encompass all messages, signals or programs as may be
provided in the normal course of television programming, including
special messages, signals or programs transmitted and received over
the usual channels to which the receivers are ordinarily tunable.
The term "program" encompasses commercials and other special
messages.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a general block diagram showing a cable television
head end constructed to deliver cable television signals, including
substitute signals to a community divided into zones;
[0016] FIG. 2 is a block diagram of a first embodiment of a cable
television head end;
[0017] FIG. 3, shows an rf cable splitter and a plurality of fiber
optic drivers;
[0018] FIG. 4 is a block diagram of a second embodiment of a cable
television head end;
[0019] FIG. 5 shows an addressable switch bay used in the
embodiment of FIG. 4; and
[0020] FIG. 6 is a block diagram of a third embodiment of a cable
television head end.
DETAILED DESCRIPTION
[0021] FIG. 1 is a general block diagram showing a targeted
television system in accordance with the present invention for
delivering cable television signals to a viewer community
represented by irregular area 101. Twenty-four zones, of which only
zones 103 through 108 have been numbered, make up the community.
Each of the zones represents an area of the community in which the
cable television subscribers are served from a single cable feed
such as cable feeds 109 and 111. The zones will not be as regular
as shown because they are determined by the cable television
company based on the economics of providing cable services. Each
zone, however, includes a number of geographically proximate
subscribers and is referred to herein as being substantially
contiguous. Further, it is possible that over time the zone
boundaries will change as new subscribers request cable service and
other subscribers give up their prior service.
[0022] Each zone, e.g. 103, includes a signal distribution point
such as 113 which receives the cable feed, e.g. 109 and distributes
the cable TV spectrum of the cable feed by means well known in the
art to the viewers in the zone. The spectrum of signals on a cable
feed, e.g. 109, is provided by a cable head end 123. Cable head end
123 includes a plurality of signal inputs 125 for receiving the
normal TV channels from over-the-air broadcasts or satellites. It
should be mentioned that the normal channels may also include
programming which is provided by the cable TV operator, such as
video tapes of community events. The sources of normal signals,
e.g., 125, are signal inputs to a television channel connection
apparatus 127, as are a plurality of input signals 128 from a
substitute channel signal source 129. In addition, the channel
connector 127 provides a plurality of normal TV channels to the
substitute signal source 129 over a plurality of connections 131.
Substitute signal source 129 and connection apparatus 127 cooperate
under the control of a computerized controller 135 to produce
television signals for three distribution trunks 142, 143 and 144.
Each of the distribution trunks 142, 143 and 144 conveys a full
spectrum of cable TV channels to a respective splitter/driver 137
which includes an 8-way signal splitter 126 and cable feed drivers,
e.g. 122, 124 (FIG. 3). By the operation of substitute signal
source 129, connector apparatus 127 and controller 135, the
television channel signals may be different on each of the
distribution trunks 142, 143 and 144, so that the feeder cables 119
and 121 may be carrying normal and substitute channels while the
feeder cables 117 and 115 of splitter/driver 139 and the feeder
cables of splitter/driver 141 may convey only normal channels.
[0023] When a market research firm begins business in a community,
the population is solicited to identify cable television
subscribers who agree to participate as market survey panelists. As
a part of acceptance as panelists, such volunteers provide the
market researcher with demographic data comprising information
about various types of personal and shopping behaviors. For
example, the volunteers may disclose the names and ages of
individuals in the panelist's household, household income and likes
and dislikes, as well as, the stores frequently shopped and the
brands frequently purchased. Based on the survey data the market
researcher can determine the traits of the panelist for later use
in analyzing market research data. Also based on the
panelist-provided information, the market researcher determines
which of the zones, e.g. 103-108, should be connected to which of
the splitter/drivers 137, 139 and 141. The goal is to
demographically select the interconnection between distribution
trunks and zones so that each distribution trunk is connected to a
"cross section" of the panelists in the community. For ease of
understanding, not all 24 feed cables from splitter/drivers 137,
139 and 141 to zones have been shown. Instead, the signal
distribution point, e.g., 113, of each zone has been given a letter
A, B or C which corresponds to the A, B or C letter assigned to the
splitter/driver connected thereto. In FIG. 1, all 8 of the zones
having a signal distribution point labeled A, e.g., 151, 152 and
153, are connected to splitter/driver 137, all 8 distribution
points labeled B, e.g., 154, 155 and 156, are connected to
splitter/driver 139 and all distribution points labeled C are
connected to splitter/driver 141. The described method of selecting
interconnection permits a demographic selection of a test group,
e.g. A, for a new (substitute) advertisement, while another group,
e.g., B, can be selected as a control group which receives normal
signals rather than the new substitute advertisement.
[0024] The connection apparatus 127 receives all channels of normal
signals and substitute channel signals and combines the received
channel signals onto the three distribution trunks 142, 143 and
144. In the present embodiment each cable subscriber receives a
spectrum of up to 60 different channels on the cable at their
household. During normal distribution the channel signals from
receivers 125 are properly channel modulated and combined as a
distribution channel spectrum on all three distribution trunks 142,
143 and 144 such that all three trunks convey the same signals.
Each of the distribution trunks 142, 143 and 144 feeds an
associated eight-way splitter/driver 137, 139 and 141. The
splitter/drivers, e.g., 137, comprise an eight-way rf splitter 126,
each output of which feeds a fiber optic driver 122, 124. The
output signals of the splitter/drivers are then conveyed to
connected distribution points, e.g. 151 and 152, via feeder cables
119 and 121. The distribution points convert the optical channel
information back to rf for distribution to the subscribers in the
zone. It should be mentioned that at least two distribution trunks
and splitter/drivers are used so that a test group and a control
group can be created. While the present embodiment uses three
distribution trunks, some panelist response testing systems may use
four or more distribution trunks and splitter/drivers. Also, the
present embodiment uses fiber optic feeder cables; however, other
types of feeder cables, such as rf coaxial cable, could be
used.
[0025] When a new advertisement is to be tested it is installed at
substitute signal source 129 and made available on a lead 128 as an
input to the connection apparatus 127. Under the control of
controller 135 connection apparatus 127 replaces normal signals in
a channel on one of the distribution trunks 142, 143 and 144 with
the new advertisement. When the substitution is made for
distribution trunk 142, the substitute signal is delivered to all
subscribers, including all panelists, in zones A. Thus the
panelists in zones A are the test group and the panelists in either
zones B or zones C, which do not receive the new advertisement, may
be chosen as a control group.
[0026] FIG. 2 shows an embodiment of a cable head end which is
equipped to provide channel substitution in the manner described
above for a 60 channel distribution system. With the present
embodiment twelve channels may be subject to signal substitution,
while the remaining 48 channels are not subject to signal
substitution. For ease of understanding the 12 substitutable
channels are channels 2-13 while the other channels are 14-61.
Other combinations of channels could easily be used. FIG. 2
includes forty-eight signal inputs 125B which are shown as off-air
antennas but could be satellite receivers or inputs resulting from
local TV cameras or VTRs. Each signal input is at base band or is
converted to base band by a respective demodulator of which
demodulators 171 and 172 are shown. The base band output of each
demodulator is then modulated by a respective fixed channel
modulator of which modulators 174 and 175 are shown. Each of the
forty-eight modulators is tuned to a different output channel so
that the outputs of all modulators 174, 175 comprises the
forty-eight channels 14-61. The output signals from each modulator
are combined by a head end combiner 177 into a spectrum of channels
14-61. Combiner 177 splits the spectrum of channels 14-61 into
three identical copies on outputs 179, 180 and 181 which are each
applied to a separate two-way combiner 183, 184 and 185. The other
input to combiners 183-185 consists of channels 2-13, which are
subject to signal substitution. The outputs of combiners 183, 184
and 185 are the distribution trunks 142, 143 and 144,
respectively.
[0027] FIG. 2 includes twelve normal channel signal inputs 125A
which, as described below, are subject to being replaced by
substitute channel signals through the use of a base band switch
187. As with channel inputs 125B, channel inputs 125A are shown as
off-air signals but other signal types may be used. Each channel
input 125A is demodulated to base band in a respective demodulator,
e.g. 189, 191, which is connected via cables 192 as an input to
base band switch 187. Up to six substitute channels, at base band,
are also connected from the market researchers as inputs 193 to
base band switch 187. It should be mentioned that the substitute
channels may also include test signals which can be switched back
to the market researchers for equipment testing on outputs 194. The
base band signals switched back to the market researchers on
conductors 194 may also include a selected normal channel so that
the substitute source can be synchronized with the normal channel
before channel substitution occurs.
[0028] Base band switch 187 responds to control signals from
controller 135 to selectively connect the inputs 192 and 193 to the
outputs of the switch. The outputs of base band switch 187 comprise
outputs 194 to the market researchers and outputs 195 which are
used to complete the channel spectrum sent to subscribers via
distribution trunks 142-144. To provide a complete spectrum of
channels 2-61 on each distribution trunk 142-144, three fixed
channel modulators for each channel 2-13 are connected to outputs
195 of the base band switch 187. In FIG. 2 modulators 161, 162 and
163 for channel 2 are all shown connected to separate outputs 195
of base band switch 187, as are modulators 168, 169 and 170 for
channel 13. Three combiners 197, 198 and 199 are used to generate
three channel 2-13 distribution spectrums which are respectively
connected as inputs to the two-way combiners 183, 184 and 185. Each
combiner 197-199 receives twelve channel inputs, one for each of
the channels 2-13. In FIG. 2 combiner 197 is connected to channel 2
modulator 161, channel 13 modulator 168 and to one modulator (not
shown) for each channel 3-12. When connected as described, the
distribution trunks 142-144 have a channel spectrum from channel 2
to channel 61 and the content of channels 14-61 is taken
substantially directly from inputs 125B and the continent of
channels 2-13 is taken from switch 187.
[0029] During nonsubstitution, the cable service provider or the
market researchers instruct switch 187, by means of controller 135,
to connect each input signal 125A to all three of the modulators,
e.g. 161, 162 and 163, for that input signal. Thus, all cable
subscribers will receive all normal channels 2-61 from their
connected distribution trunks 142-144. When a substitution is to
occur, for example, on channel 2 for subscribers connected to the A
feed, the market researchers control switch 187 to connect the
normal channel 2 signal to the market researchers via paths 194 as
well to the three channel 2 modulators 161, 162 and 163. The market
researchers obtain synchronism information for channel 2 from the
channel 2 signal which they receive on path 194. At the moment for
signal substitution, the market researchers send the substitute new
advertisement to an input, e.g. 193a, of switch 187 which is
controlled to connect the input 193a receiving the substitute
signal to the output connected to modulator 161. The exact moment
of substitution is determined from the synchronism information
received from normal channel 2, as is well known in the art. While
the substitute advertisement is being input to switch 187 it is fed
on channel 2 to all subscribers, including panelists, connected to
distribution trunk 142. Those panelists connected to distribution
trunks 143 and 144 continue to receive normal channel 2 signals
from inputs 125A. At the end of channel substitution, switch 187 is
controlled to disconnect input 193a and to connect the channel 2
input signal directly from input 125A to modulator 161. During the
time of signal substitution, the substitution signals are sent to
approximately one-third of the cable subscribers. Given the
demographic selection of which zones are connected to the
distribution trunks, a proper test group of panelists has received
the substitute signals. Similarly, the panelists connected to
distribution trunks 143 and 144 have received the normal signals
and can form the control group.
[0030] FIG. 2 shows a market research computer system 145 which is
connected to the market research organization, the scan networks
159 of local retail stores, to the telephone network 160 for other
panelist information and to the controller 135. The market research
computer system, which may comprise multiple computers, stores
lists of the panelists connected to each of the distribution trunks
142-144. During signal substitution it is informed by the
researchers, on which trunk the substitute commercial was carried.
The market research computer system 145 can use this information to
evaluate panelist data collected at local retail stores.
[0031] In the description of FIG. 2, base band switch 187 has been
shown to include 12 input signal 125A ports and 6 substitute signal
input ports as well as 36 channel output ports and a plurality of
market research output ports 194. It should be mentioned that other
combinations of substitute and normal signal inputs and other
numbers of channel output ports 195 can be used. Although a larger
base band switch 187 would be needed, the system of FIG. 2 could
include, for example, 18 input sources 125A, and 9 substitute
sources 193. Such a system would require 54 (3.times.18) output
ports 195, each with a fixed channel modulator such as modulator
170.
[0032] FIG. 4 shows a block diagram of a cable head end system
which may be used as an alternative to the cable head end system of
FIG. 2. The system of FIG. 4 provides the three distribution trunks
142-144 each conveying a spectrum of 60 cable TV channels. The
signals of any of the 60 channels may be substituted in the manner
described below. 60 input signal sources 125 are used in the system
to provide signals for all channels. Although the input signal
sources are shown as off air antennas, they may be cable feeds,
satellite receivers or VTRs, as is common in the provision of cable
TV services.
[0033] The input signals from sources 125 are demodulated (171,
172) if received at rf, and each is modulated to the frequency of a
unique one of the 60 channels 2-61 in respective modulators. Of the
60 modulators, only two are specifically shown, e.g., 173, 175. The
output of each modulator, e.g. 173, is applied as an input to a
four-way splitter, e.g. 201, 203. Accordingly, 60 four-way
splitters 201, 203 are present in the system. One of the outputs of
each four-way splitter is connected by rf cable to a channel group
combiner 208. In FIG. 2, cable 205 connects four-way splitter 203
to group combiner 208 and cable 206 connects four-way splitter 201
to the channel group combiner. A broad vertical line 240 represents
a bundle of individual coaxial cables, each conveying one modulated
channel. The channel group combiner 208 thus receives 60 rf cables
each conveying signals from one of the input signal sources 125 in
a unique television channel. A plurality of cable channel combiners
(not shown), as are well known in the art, make up combiner 208
which combines all received channels onto a single 60 channel
spectrum on an rf coaxial cable 209. A signal splitter 211 receives
the channel spectrum on cable 209 and splits the spectrum into a
plurality of identical copies. As will be seen, the number of
copies represents the number of channels on which signal
substitution can be simultaneously occurring. The present
embodiment allows 6 channels to be simultaneously substituted,
which results in splitter 211 being an eight-way splitter with two
outputs unconnected.
[0034] Each of the six active outputs of splitter 211 is connected
to a frequency agile demodulator (FAD) of which 213 and 215 are
shown in FIG. 4. The frequency agile demodulators receive control
signals from controller 135, via a control bus 235, which determine
the particular television channel they are to receive and
demodulate. For example, demodulator 213 may receive from
controller 135 signals defining channel 2 and demodulator 215 may
receive signals defining channel 17. Thereafter, demodulators 213
and 215 demodulate the signals in channels 2 and 17 of cable 209,
respectively, and apply the resulting base band signals as inputs
to a video switch 217.
[0035] In the present embodiment video switch 217 is a twelve input
by twelve output switch which connects signals at the input ports
to output ports defined by controller 135. Six input ports are
connected to the base band output signals of the frequency agile
demodulators 213, 215 and six inputs are connected to base band
signals from six substitute signal sources, of which sources 219
and 221 are specifically shown in FIG. 4. Six of the twelve output
ports of video switches 217 are connected to frequency agile
modulators (FAM) of which frequency agile modulators 223 and 225
are shown. The remaining six outputs of video switch 217 are
connected by leads 226 as inputs to a vertical blanking internal
(VBI) timing unit 227. VBI unit 227 identifies timing information,
including vertical blanking information, from each signal on leads
226 and is interrogated from time to time by controller 135. On the
basis of the synchronizing information, switching can be commanded
by controller 135 during the vertical blanking interval.
[0036] Frequency agile modulators 223, 225 respond to commands
received from controller 135 via bus 235 to modulate base band
signals received from video switch 217 to a television channel
identified in the command from the controller. For example,
frequency agile modulator 223 may be commanded to generate output
signals modulated to channel 2 and frequency agile modulator 225
may be commanded to generate output signals modulated to channel
17. When output signals in another channel, e.g. channel 9, are
needed, new commands are sent to an available modulator, e.g. 213,
to change its modulation frequency to channel 9. The output of each
frequency agile modulator is applied to respective three-way
splitter of which three-way splitters 237 and 238 are shown
connected to modulators 223 and 225, respectively.
[0037] The embodiment of FIG. 4 includes three switched combiners
245, 246 and 247, each of which is connected to receive an input
cable from all 60 four-way splitters 201, 203 representing input
signals and is connected to the three-way splitters 237, 238
conveying channels modulated by the frequency agile modulators 223
and 225. Thus each switched combiner 245, 246 and 247 is connected
to .DELTA.66 coaxial cables, each conveying signals modulated to
one cable TV channel. Each switched combiner comprises 6
addressable switch bays 250, each comprising 12 single pole, single
throw rf switches labeled J1-J12 in FIG. 5. The switch bay also
includes an address decoder with a manually settable address 251
and a connection 253 to the control bus 235. The address decoder
responds to address commands from controller 135 by turning one of
the switches J1-J12 on or off as specified in the command. After a
command to enter a state, a switch remains in that state until
commanded to change state. The outputs of the switches J1-J12 are
connected as inputs to a plurality of rf combiners which are
connected to produce a spectrum of TV channels 2-61 on a
distribution trunk, e.g. 142. As shown in FIG. 4, the switched
combiners 245, 246 and 247 generate a spectrum of TV channels on
distribution trunks 142, 143 and 144, respectively.
[0038] The spectrum of channels applied to any of distribution
trunks 142, 143 and 144 is determined by the individually
addressable switched combiners 245, 246 and 247. When only normal
channels from input signals 125 are to be sent on distribution
trunk 142, switched combiner 245 receives addressed commands from
controller 135 to turn on all 60 switches connecting the input
signal sources 125, via their respective channel modulators, to the
distribution trunk. The other switches of switched combiner 245 are
turned off. When a signal is to be substituted in a given channel
on distribution trunk 142, switched combiner 245 is commanded to
switch the given channel from input signals 125 off and the
substitute signal from video switch 217 (in the given channel) on.
Controller 135 performs such switching on and off during the
vertical blanking interval as identified by vertical blanking
interval timing unit 227.
[0039] The following illustrates the delivery of substitute signals
in channel 17 on distribution trunk 142. Initially, all channels on
distribution trunk 142, including channel 17, are selected by
switched combiner 245 from the input sources 125. At a time prior
to actual substitution, controller 135 sends to an available
frequency agile demodulator, e.g. 215, a command specifying channel
17 and sends to an available frequency agile modulator, e.g. 225, a
command also specifying channel 17. Controller 135 also sends to
video switch 217 a command directing that the switch input of
frequency agile demodulator 215 be switched to the switch output of
frequency agile modulator 225. After frequency agile demodulator
215, video switch 217 and frequency agile modulator 225 have
responded, a copy of the channel 17 signals from input source 125
is available at the output of three-way splitter 238 and at an
input of vertical blank timer unit 227. Switched combiner 245 is
then commanded during a vertical blanking interval to turn off the
switch J1-J12 connected to the channel 17 input signal source 125
and to turn on the channel 17 input from three-way splitter 238. At
this point, channel 17 is delivered to the subscribers connected to
distribution trunks 143 and 144 directly from the input source 125
and channel 17 is delivered to the subscribers connected to
distribution trunk 142 via the channel group combiner 208 and video
switch 217. When the time for signal substitution occurs, as is
recognized by an operator at the market researcher, substitute
signal source, e.g. 219, is started and controller 135 commands
video switch 217 to connect the switch input of signal source 219
to the output connected to frequency agile modulator 225. At the
same time the prior connection between frequency agile demodulator
215 and frequency agile modulator 225 is broken. This removes the
normal signals from channel 17 on distribution trunk 142 and
replaces them with the substitute signals from source 219. During
the time of signal substitution the substitute signal from source
219 will be available on distribution trunk 142. At the conclusion
of the substituted signal, the video switch 217 is commanded to
reconnect frequency agile demodulator 215 to frequency agile
modulator 225 so that the continuing normal signal of channel 17
will be connected to distribution trunk 412. When all substitution
for channel 17 is completed, switched combiner 245 is commanded to
turn off the channel 17 connection from the video switch 217 and to
turn on the channel 17 signal from the input sources 125.
[0040] FIG. 6, which comprises an alternative embodiment for the
cable head end, is largely the same as FIG. 4. With the system of
FIG. 6, each switched combiner 245, 246 and 247 is directly
connected to two of the frequency agile modulators, e.g. 223 and
275. That is, the output of each frequency agile modulator is not
split into three copies and applied to all switched combiners as is
done in the embodiment of FIG. 4. In the system of FIG. 6, only two
channels can be simultaneously substituted on each of the
distribution trunks 142, 143 and 144 and, when a signal is to be
substituted on each of the distribution trunks 142, 143 and 144, a
switch path must be set up through video switch 217 to a frequency
agile modulator, e.g. 223, 225 and 276 connected to the
distribution trunk.
[0041] When replacing one channel signal with another, it is
desirable that both signals are of similar level so that
subscribers will not be aware of the substitution. FIG. 6 includes
signal sampling and amplitude control apparatus to correct signal
level mis-matches. Signal levels and gains throughout the system
are controlled by fixed means so that the signal levels from
four-way splitters 201 and 203 are lower than the signal levels
from frequency agile modulators 223, 225 and 275-278. An
electronically controlled attenuator 268-273 serially connects the
output signals from the frequency agile modulators to their
respective switched combiners 245-247. Control for the attenuators
260-273 is sent by controller 135. The signals on each distribution
trunk 142-144 are split by splitters 283-285, respectively, and
communicated to a selector 294 which also receives signals
representing the outputs of attenuators 268-273 which are taken by
a plurality of splitters 291-286, respectively. Selector 294
comprises a selector switch having 9 inputs, one from each splitter
283-291, and one output 295. A carrier measurement unit, which
includes a controllable tuner and a carrier amplitude measurement
unit (not shown), is connected to the output 295 of selector
294.
[0042] When signals are about to be substituted, controller 135
directs selector 294 to connect a particular distribution trunk,
e.g. 142, to carrier measurement unit 296 and directs the tuner of
carrier measurement unit 296 to tune to the particular channel to
be substituted. The level of the carrier is then measured and
signals representing that measurement are returned to controller
135. Similarly, selector 294 is controlled to connect the
substitute channel splitter, e.g. 291, to the carrier measurement
unit 296. Carrier measurement will occur at the same channel
carrier frequency as was measured from trunk 142. The two
measurements are compared by controller 135 which then directs via
bus 235 the relevant attenuator, e.g. 268, to attenuate the signals
at the output of frequency agile modulator 223 to the same level as
those sensed on trunk 142. Thereafter, the attenuation level
provided at attenuator 268 will remain the same until a new
substitution is proposed. It should be mentioned that the signal
matching capabilities shown and described with respect to FIG. 6
are easily applied to the embodiments of FIGS. 2 and 4.
[0043] In the preceding embodiments, demodulators 171, 172, 189 and
191 may be, for example, Scientific Atlanta Demodulator No. 6250,
and may include necessary receiving apparatus as is well known in
the art. Modulators 161-163, 168-170, 173 and 175 may be, for
example, No. 6350 by Scientific Atlanta. The video switches 217 and
187 may be Dynair System 21 routing switches configured with the
required number of input and output ports. Also, the embodiments
describe systems having an exemplary number of cable channels and
substitutable channels and signal sources. The number of channels
and signal sources are discussed by way of example and are not
limited to those described. The preceding description relates to
specific examples of systems embodying the present invention. The
described systems can be modified by persons of ordinary skill in
the art without departing from the spirit and scope of the present
invention which is defined by the claims attached hereto.
* * * * *