Patent Publication Number: US-6662007-B2

Title: Cordless phone back link for interactive television system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 08/914,336, filed Jul. 14, 1997, now U.S. Pat. No. 5,898,919, which claims the benefit of U.S. Provisional Application No. 60/012,303, filed Feb. 26, 1996; U.S. Provisional Application No. 60/012,968, filed Mar. 7, 1996; U.S. Provisional Application No. 60/027,671, filed Oct. 7, 1996; and International Publication Number W097/31480, published Aug. 28, 1997 PCT Application No. PCT/US97/02888, filed Feb. 26, 1997. 
    
    
     FIELD OF THE INVENTION 
     This invention relates generally to television and telephone systems and more specifically to an interactive television system integrated with cordless phone circuitry to allow automatic telephonic communication between the interactive television system and a central site. 
     BACKGROUND OF THE INVENTION 
     An emerging trend in the marketing of cable television and digital satellite systems (DSS) is to emphasize Pay-Per-View (PPV) television programming as a source of revenue. An ideal PPV television system should allow a viewer to purchase the right to watch a television program such as a movie, sporting event, or other special event through a minimal amount of effort on the part of the viewer. For example, after watching a short preview or advertisement of a PPV program, the viewer could gain access to the PPV program simply by pressing a selected button on the viewer&#39;s remote control unit for a television or video cassette recorder (VCR). In another example, the viewer is watching an informational commercial (“infomercial”) or a home shopping program and the viewer desires to purchase an advertised product by pressing a selected button on the remote control unit. In existing television systems, in order for the viewer to arrange for PPV program access, the viewer must go to the viewer&#39;s telephone, call the PPV program provider (such as the cable company) and enter his or her cable box serial number, credit card number and PPV program identifier. The PPV program provider then enables the cable box to display the selected PPV program to the viewer. In the home shopping situation, the viewer must write down the advertiser&#39;s telephone number and product identifier, go to the telephone, call the advertiser or a home shopping service provider, and then communicate the required credit card and product selection information to an operator. 
     In more recent systems using digital set top boxes (such as DSS), the set top box itself is directly connected to a telephone line in the viewer&#39;s home and the remote control unit includes a button for ordering a PPV program. When the button is pushed by the viewer, the telephone number of the PPV program provider is automatically dialed and the box identifier and PPV program identifier are automatically transmitted over the telephone connection to the PPV program provider. In this scenario, the viewer must establish a credit card account with the PPV program provider for billing purposes prior to pushing the button to select a PPV program. A major drawback to effective operation of these systems is the requirement that the set top box and television must be close to a telephone jack in the viewer&#39;s home, because of the direct connections by wire between the set top box, the television and the telephone jack. In many homes, the television is not in close proximity to a telephone jack, nor even in the same room, thereby rendering such systems unsuitable for widespread use. An interactive television system overcoming this drawback would have considerable value in the PPV, home shopping, and other interactive viewing situations. 
     SUMMARY OF THE INVENTION 
     A system for communicating information from a television viewer to a central site includes a remote control unit for sending command signals from the viewer to a television or video cassette recorder (VCR). Circuitry integral with the television or VCR accepts the command signals from the remote control unit and interprets the signals to form a viewer command, such as a purchase command, to be communicated to the central site. The circuitry automatically sends dual-tone multifrequency (DTMF) tone signals representing the command over a radio frequency (RF) link to a cordless telephone base unit which is connected to the central site by a public switched telephone network. The cordless telephone base unit initiates a telephone call to the central site and communicates the DTMF tone signals received from the DTMF circuitry to the central site. Because of the advantages of RF communication, the television or VCR does not have to be in the same room as, or in close proximity to the cordless telephone base unit. The television receives a television signal and extracts information related to a product being advertised on a television program from the vertical blanking interval of the television signal. This information may include the telephone number of the central site used for making the telephone connection as well as identification information for products. A cordless telephone handset in communication with the cordless telephone base unit is also included to allow the television viewer or other user to make normal telephone calls with the cordless telephone. 
     In an embodiment of the present invention, a method of purchasing a product advertised on a program displayed by a television includes reception of a purchase command by a remote control unit of the television, transmission of the purchase command over an infrared link to the television, and initiation of a telephone connection by a cordless telephone base unit to a central site. The purchase command is then sent by dual-tone multifrequency signal generation circuitry resident in the television over a radio frequency link to the cordless telephone base unit. The cordless telephone base unit sends the purchase command to the central site over the telephone connection. The central site then processes the purchase command. 
     In another embodiment of the present invention, the circuitry for sending the DTMF tone signals is included in the remote control unit instead of the television. In this embodiment, when the viewer pushes a button on the remote control unit to communicate information such as a purchase command to the central site, the remote control unit directs the DTMF circuitry to send the DTMF tone signals representing the viewer&#39;s command to the cordless telephone base unit. These DTMF tone signals are then forwarded over the telephone connection to the central site. In this embodiment, the television still extracts information from the vertical blanking interval of the television signal, but the extracted information is transmitted to the remote control unit for processing. 
     Still other objects and advantages of the present invention will become readily apparent to those skilled in the art from the following detailed description, wherein is shown and described only the preferred embodiment of the invention, simply by way of illustration of the best mode contemplated for carrying out the invention. As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a block diagram of the present invention. 
     FIG. 2 is a schematic diagram of the DTMF Circuit. 
     FIG. 3 is a functional block diagram of a data transmission system for television signals. 
     FIG. 4 is a block diagram illustrating the main components of the Television and Remote Control Unit. 
     FIG. 5 is a block diagram of an alternate embodiment of the present invention. 
     FIG. 6 is a flow chart illustrating the high level operational steps of the present invention. 
     FIG. 7 is a schematic of a menu display for a list of service providers. 
     FIG. 8 is a schematic of a menu display for a list of available items from a selected service provider. 
     FIG. 9 is a schematic of a display to inform the viewer of the status of the telephone order. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention is a back link system connecting a television, VCR, or other device (hereafter denoted as “television”), heretofore primarily designed to only receive information from a central site, to a cordless telephone base unit by enabling the television to operate certain functions of a cordless telephone handset. The present invention includes the functionality of the cordless telephone handset in the television, thereby enabling the television to directly initiate a telephone call through the cordless telephone base unit and to send selected information from a viewer or user via the telephone connection over the public switched telephone network to a central site. 
     FIG. 1 is a block diagram of the present invention. Television  10  receives a Television Signal  12  from a signal source. The Television  10  could be a standard television, a VCR, or any other device capable of tuning television signals. The Television Signal may be received from an antenna, a cable, a satellite signal, or any other transmission medium for television signals. The Television  10  includes a Dual-Tone Multifrequency (DTMF) Circuit  14 . 
     The DTMF Circuit  14  is similar to the corresponding portion of a well known cordless telephone handset. However, the DTMF Circuit does not include such typical handset features as a microphone, loudspeaker, ringer speaker, volume control, on/off switch, hold key, mute key, push button keypad, and rechargeable battery, because the DTMF Circuit does not directly interact with a user of the telephone. Hence, the manufacturing cost of the DTMF Circuit can be kept quite low in comparison to the typical cordless telephone handset. Note that the primary purpose of the DTMF Circuit is to transmit DTMF tone signals to a pre-existing Cordless Telephone Base Unit  16 . It is not necessary that the DTMF circuit transmit voice signals or receive voice or DTMF tone signals. The pre-existing Cordless Telephone Base Unit  16  may be in communication with a standard Cordless Telephone Handset  17 . The Base Unit-Handset combination may be used by the television viewer or other user to make telephone calls in the normal way. The DTMF tone signals are used to dial the telephone and to transmit alphanumeric data needed to complete a viewer transaction such as the purchase of a product or a PPV television program. 
     Note that the present invention uses a pre-existing cordless telephone having a base unit and a handset to form a two-way transmission link with a television. The Cordless Telephone Base Unit  16  performs not only its conventional function of a transmission link between the public switched telephone network and the Cordless Telephone Handset  17 , but also a transmission link between the public switched telephone network and the Television  10 . In other words, the Cordless Telephone Base Unit performs two functions. 
     The DTMF system uses internationally standardized combinations of frequencies. Alphanumeric characters are encoded in the form of two pairs of tones for transmission via the telephone lines. In conventional DTMF signaling, the numbers and symbols present on a telephone keypad are each transmitted as a dual-frequency tone. For example, the number “1” is represented by a tone comprised of the frequencies 697 Hz and 1209 Hz, and the star symbol “*” is represented by a tone at the frequencies 852 Hz and 1477 Hz. A total of seven different frequencies are utilized in pairs to transmit the ten numbers and two symbols on a conventional telephone keypad. In some systems, four additional characters are provided. Table I is a matrix showing the high and low frequency pairs, in Hz, required for each of the 16 possible characters. Each character is represented by a dual set of audio frequency signals, which when transmitted together are recognized as the unique representation of the character. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                 Lower 
                 Higher 
                 Higher 
                 Higher 
                 Higher 
               
               
                 Frequency 
                 Frequency 
                 Frequency 
                 Frequency 
                 Frequency 
               
               
                 (Hz) 
                 1209 
                 1336 
                 1446 
                 1633 
               
               
                   
               
             
            
               
                 697 
                 1 
                 2 
                 3 
                 A 
               
               
                 770 
                 4 
                 5 
                 6 
                 B 
               
               
                 852 
                 7 
                 8 
                 9 
                 C 
               
               
                 941 
                 * 
                 0 
                 # 
                 D 
               
               
                   
               
            
           
         
       
     
     To transmit alphabetic characters over the telephone lines as well as the conventional numbers and symbols, the seven standard frequencies 697 Hz, 770 Hz, 852 Hz, 941 Hz, 1209 Hz, 1336 Hz, and 1447 Hz are used, and an eighth frequency, normally unused, is also employed. The eighth frequency has a value of 1633 Hz. The additional frequency is used only for transmission of characters that are not typically transmitted via DTMF signaling. To indicate the transmission of an alphabetic character, the first tone in a pair of tones which identify the letter includes the eighth frequency as a component thereof. Each letter is comprised of a first tone which includes the eighth frequency in combination with one of the seven conventionally employed frequencies, followed by a second tone comprised of any two of the eight available frequencies. Similarly, other non-conventional characters, such as punctuation and spaces, are transmitted by generating a unique pair of dual-frequency tones. 
     The DTMF Circuit may be enhanced to also provide DTMF reception capabilities, however, voice reception is not needed. With this feature, it can be determined whether a dial tone is available on the telephone line, that the line is not busy, or that confirmation data concerning a transaction is received. 
     FIG. 2 is a schematic diagram of the DTMF Circuit  14 . An Isolation Circuit  100  is provided which is connected to Antenna  102  and which is connected through Line  104  to the output of a Transmitter Section  106  and also through Line  108  to the input of an optional Receiver Section  110 . A voltage supply input of the Receiver Section  110  is connected through Line  112  to Control and Switching Circuitry  114 , which is connected to Microprocessor  116  to control operation of the Receiver Section  110 . The output of the Receiver Section  110  is connected to Line  118 , which is connected to an input of 1633 Hz Detector  120 . The output of 1633 Hz Detector  120  is applied through Line  122  to Control and Switching Circuitry  114 . A control input to the 1633 Hz Detector  120  is connected through Line  124  to an output of the Microprocessor  116 , which is also connected to Control and Switching Circuitry  114 . Microprocessor  116  includes a tone generator which may be a standard type of DTMF integrated circuit. When a 1633 Hz signal is produced at the output of the Receiver Section  110  and detected by 1633 Hz Detector  120 , the Microprocessor  116  operates to engage communications with Television  10  over Line  126 . DTMF tones received by Receiver Section  110  are applied through Line  112  to Control and Switching Circuitry  114 , wherein the DTMF tone signals are converted to digital signals. The digital signals are sent thereafter to Microprocessor  116  for eventual transmission to Television  10  over Line  126 . 
     To transmit DTMF tone signals from the DTMF Circuit  14  to the Cordless Telephone Base Unit  16 , a Summing Amplifier  128  is provided which has an output connected through Line  130  to Transmitter Section  106  to frequency modulate the output of the Transmitter Section. Control inputs of the Transmitter Section  106  are connected through Line  132  to the Control and Switching Circuitry  114 . The Microprocessor receives digital signals for transmission over Line  134  from the Television  10 . The Microprocessor operates to apply a 83 Hz square wave signal through Line  136  to 83 Hz Filter  138 , which is connected through Line  140  to an input of Summing Amplifier  128 . The output of the Transmitter Section is then modulated to send out a substantially sinusoidal 83 Hz burst which signals the Cordless Telephone Base Unit  16 . 
     After a 83 Hz burst is sent, the Microprocessor  116  develops a 98 Hz coded signal on Line  142  which is applied as a second input of the Summing Amplifier  128 . The coded signal is detected by the Cordless Telephone Base Unit and, if properly received, the Cordless Telephone Base Unit develops a 1633 Hz “handshake” signal which is transmitted back to the DTMF Circuit to be detected by 1633 Hz Detector  120 . Then the Microprocessor  116  operates to develop a 98 Hz coded null signal on Line  142  for transmission by the Transmitter Section  106 . If the null signal is properly detected by the Cordless Telephone Base Unit, the transmission of the 1633 Hz “handshake” signal is terminated and the Microprocessor responds to the termination of the “handshake” signal by developing another coded signal on Line  142  for transmission, the sequence being repeated until communications are deemed to be effectively established. Power for the DTMF Circuit is supplied by the Television  10  over Line  144 . Clock circuitry of the Microprocessor  116  is connected to a Crystal  146  through a Resistor  148  to power Line  144 . 
     The Cordless Telephone Base Unit  16  then operates to connect to an outside telephone line and to allow transmission of a dial tone back to the DTMF Circuit  14 . The DTMF tone signals for the telephone number to be dialed are then transmitted from the Microprocessor  116  to the Cordless Telephone Base Unit  16  and the Cordless Telephone Base Unit establishes the telephone connection. DTMF tone signals representing viewer transaction information may now be sent from the Television  10  to the Central Site  22  through the Cordless Telephone Base Unit  16  and Telephone Line  20 . 
     In an alternate embodiment, the DTMF Circuit could be set up to be compatible with a viewer&#39;s existing cordless telephone base unit. Some cordless telephones include digital code security to prevent other handsets from communicating with the base unit. The handset and base unit of the cordless phone share a digital code. The DTMF Circuit  14  could be set up to receive and use this code (using learning remote or stored setup data methods) much like universal infrared remote controllers. Alternatively, it is foreseen that cordless telephone manufacturers may include a code that when received by the Cordless Telephone Base Unit  16 , would disable this security feature. Accordingly, the DTMF Circuit could be set up to transmit the disable code specific to the Cordless Telephone Base Unit, again using learning remote or stored setup data methods. 
     Referring back to FIG. 1, DTMF Circuit  14  and Cordless Telephone Base Unit  16  communicate over a plurality of communication channels via radio frequency (RF) link  18 . Hence, the DTMF Transmitter and the Cordless Telephone Base Unit each include an antenna (not shown in FIG. 1) for transmission and reception of RF signals. Full duplex communication between the Cordless Telephone Base Unit  16  and the DTMF Circuit  14  is obtained by frequency modulation and demodulation of signals on FCC-designated channels. The RF link may be implemented as a 900 MHz Digital Spread Spectrum communication path, as is provided, for example, by the circuitry contained in the model CLT-926 cordless telephone commercially available from Sanyo Consumer Electronics. Spread spectrum is a modulation technique in which the information content of a modulated wave form is spread over a wider bandwidth than that of the original information signal. A spread spectrum system takes an input signal, mixes it with FM noise and “spreads” the signal over a broad frequency range, hopping from frequency to frequency at split-second intervals. The spread signal has a greater bandwidth than the original message and is less likely to interfere with other signals. 
     A general overview of spread spectrum technology is provided by R. C. Dixon,  Spread Spectrum Systems,  published by John Wiley &amp; Sons, New York, N.Y., 1984. One type of spread spectrum modulation is frequency hopping. According to Dixon, a frequency hopping system or “frequency hopper” consists of a code generator and a frequency synthesizer capable of responding to the coded output from the code generator. Also, according to Dixon, “frequency hopping” modulation is more accurately termed “multiple-frequency, code-selected, frequency shift keying.” It is simply frequency shift keying (FSK) except that the set of frequency choices is greatly expanded. Simple FSK most often uses only two frequencies; for example, F1 is sent to signify a “mark,” F2 to signify a “space.” Frequency hoppers, on the other hand, often have thousands of frequencies available. The number of frequency choices and the rate of hopping from frequency to frequency in any frequency hopper is governed by the requirements placed on it for a particular use. Cordless telephone sets designed to operate in a frequency hopping system are now widely available from manufacturers such as Lucent Technologies, Motorola, Sharp, and others. 
     By using digital spread spectrum communications, RF link  18  exhibits superior noise immunity, longer operating range, automatic best channel selection, and superior security against eavesdropping. However, RF Link  18  may also be implemented by cordless telephone circuitry operating over a selected one of  10  channels allocated in the 46-50 MHz FCC-allocated frequency band. 
     Instead of being integral with the Television  10 , the DTMF Circuit  14  could also be a stand-alone unit, i.e. a “set top box”, which is directly connected into a telephone jack of a DSS or into a digital cable box. 
     The Cordless Telephone Base Unit  16  may or may not be located in the same room as the Television  10  and DTMF Circuit  14 . For effective operation, the distance between the Cordless Telephone Base Unit and the DTMF Circuit may extend up to several hundred feet, which is more than adequate for residential applications. The Cordless Telephone Base Unit  16  is arranged to be connected to at least one telephone line and also to a 120-volt alternating current (AC) line cord (not shown) for plugging into a standard electrical outlet. Alternatively, the connection to the public switched telephone network can be via a cellular network. The Cordless Telephone Base Unit  16  may include one or more control and signaling buttons (not shown). An exemplary embodiment of the Cordless Telephone Base Unit is shown in U.S. Pat. No. 4,706,274, issued to Baker et al., entitled “Cordless Telephone System” and incorporated herein by reference. The Cordless Telephone Base Unit may include such features as a built-in speaker, microphone, line select button, hold button, intercom call switch, answer button, volume control knob, and various lights to indicate such events as power availability, incoming calls and hold status. The Cordless Telephone Base Unit would not necessarily have to include a receptacle for a cordless telephone handset because portions of the typical telephone handset are integral with the Television  10 ; thus there may be no need for such a receptacle. For similar reasons, the Cordless Telephone Base Unit would not have to include a portable handset battery recharger. However, pre-existing Cordless Telephone Base Unit  16  could be employed without modification with pre-existing Cordless Telephone Handset  17  to make telephone calls in the usual way. In other words, Cordless Telephone Base Unit  16  can perform dual functions—serve as a standard telephone for two way voice transmission and serve as a data transmission link from a television to a telephone network. 
     The Cordless Telephone Base Unit  16  could also be used as an answering telephone completely independent of the DTMF Circuit  14 . To receive a call at the Cordless Telephone Base Unit, an answer button (not shown) is pressed and the Cordless Telephone Base Unit operates as a conventional “speaker phone.” 
     The Cordless Telephone Base Unit  16  is coupled via public switched telephone network  20  with Central Site  22 . The Central Site includes components to answer the incoming telephone call, receive the transaction data from the Cordless Telephone Base Unit, implement the transaction, and send confirmation data back to the Television. The Central Site represents the centrally located PPV program provider, cable company, or broadcast television station or network. Typically, the Central Site will include a well known general purpose computer system and associated circuitry for performing the above functions. 
     The Cordless Telephone Base Unit  16  can also communicate with other telephones such as Party  21  through the public switched telephone network  20 . 
     In the preferred embodiment of the present invention, PPV or home shopping control information is embedded in the television signal at the Central Site  22  or other location and extracted from the Television Signal  12  by the Television  10  (the extraction and control capability may also be included in a VCR or other appliance). One method of embedding the information into the television signal is to embed the information in the vertical blanking intervals (VBIs) of the Television Signal. The vertical blanking intervals can contain closed caption data for the hearing impaired and extended data services (EDS) data. 
     Video images in a cathode ray tube (CRT) video device, e.g. television, are generated by scanning a beam along a predefined pattern of lines across a screen. Each time all of the lines are scanned, a frame is said to have been produced. In the National Television Standards Committee (NTSC) implementation, such as is used in the United States, a frame is scanned  30  times per second. Each television frame comprises  525  lines which are divided into two separate fields, referred to as field  1  (“odd field”) and field  2  (“even field”), of 262.5 lines each. Accordingly, these even and odd fields are transmitted alternately at 60 Hz. The lines of the even and odd fields are interleaved to produce the full  525  line frame once every {fraction (1/30)} of a second in a process known as interlacing. Another standard in the world uses 625 lines of information and interlace  312  and  313  lines at 50 fields per second. In the 525 line NTSC standard used in the United States, approximately 480 lines are displayed on the television screen. 
     The interlacing scanning pattern of a conventional television receiver includes scanning the CRT beams from the top left corner horizontally across the screen. After the first, topmost line is scanned, the beam returns to the left side during a period of time known as the horizontal blanking interval and repeats scanning along another line which is parallel to but lower than the previous line. The scanning continues along the lines until the beam reaches the center of the bottom part of the screen to complete field  1 . 
     From the bottom of the screen, the beam returns to the top where it starts scanning from substantially the center of the screen along the lines for field  2  which interlace the lines of field  1 . This is not an instantaneous bottom to top jump but actually requires the length of time to scan  21  horizontal lines. These lines are lines  1  through  21  of field  2 . The second half of line  21 , field  2  is displayed. Then lines  285  to  525  of fields  2  are scanned to complete field  2 . When the beam reaches the bottom right corner of the screen, the picture frame is formed. The beam then retraces to the top. 
     During the time in which the beam returns from the bottom to the top of the screen between the fields, it carries no video or picture signals because it does not produce any picture element on the screen. This time interval is generally known as the vertical blanking interval (VBI). Its duration is typically 21 times the time duration that it takes the beam to scan across the screen. Apparatus and methods using the NTSC standard with 21 lines in each VBI are well known in the art and therefore are not discussed in further detail herein. 
     Because no image is produced on the display during the VBI, no picture information needs to be carried by the television broadcast signals. Thus, the VBI is used for conveying auxiliary information from a television network or station to viewers. For example, closed caption data associated with the television program are transmitted as encoded composite data signals in VBI line  21 , field  1  of the standard NTSC video signal. Lines  1  through  9  of the VBI of each field are used for vertical synchronization and post equalizing pulses. Hence, lines  10  through  21  are available for carrying auxiliary information. 
     FIG. 3 is a functional block diagram of a data transmission system for television signals. As used herein, the terms “broadcast” and “transmit” are used interchangeably for the transmission of signals over cable or fiber optics, to or from satellites, over the air, and the like. The data transmission system is the source for the Television Signal  12  received by the Television  10  of FIG. 1. A Network Head End  160  transmits a composite television signal containing inserted information in a portion thereof, typically the vertical blanking interval, to a Satellite  162  which rebroadcasts the same to a local Affiliate  164 . The Affiliate  164  may further insert data into the VBI of the received television signal and transmit the same to a local Cable Head End  166 . The Cable Head End  166  receives television signals from a plurality of sources (including satellites) and may further insert data into the VBI of any of the television signals. The signals from the plurality of sources are combined into a composite television signal, amplified, and provided over a cable to a plurality of individual Receivers  168 . In the preferred embodiment, Television  10  from FIG. 1 is an example of a Receiver  168 , however, Receivers can include cable boxes, VCRs, and satellite receivers as well as televisions. In addition, the individual Receivers  168  may receive signals directly from local Affiliate  164  by air, which may include the use of a Satellite  162 , or by cable. 
     More specifically, the Network Head End  160  has a video tape recorder (VTR)  170  for providing a program signal to an Inserter  172 . A Controller  174 , also at the head end controls the scheduling of loading tapes from a cart (e.g., a machine with a plurality of video tape cassettes which are moved by a robotic arm from a storage location and inserted into a VTR and vice versa). Furthermore, the Controller  174  controls the lighting of stages during live television broadcasts, such as news broadcasts. The Controller  174  is typically a microprocessor-based system. A Traffic Computer  176  controls the exact timing of playing individual segments of video tapes and inserting commercials therebetween as well as switching between different programs. Some Network Head Ends  160  have both a Traffic Computer  176  and a Controller  174 . 
     The Controller  174  provides data and commands to the Inserter  172 . The Traffic Computer  176  provides data and commands to the Controller, if present. Otherwise, the Traffic Computer provides these signals directly to the Inserter  172 . The Inserter  172  inserts data into the VBI of the composite television signal and provides the television signal to a Transmitter  178 , which in turn provides the television signal on a microwave carrier to Satellite Dish  180  for transmission to Satellite  162 . 
     The Satellite  162  retransmits the received signal, which is received by a Satellite Dish  182  at the Affiliate  164 . The Satellite Dish  182  provides the signal to a Station Inserter  184  at the local Affiliate  164 . The Affiliate may also insert data into the composite television signal. The television signal is then provided to a Transmitter  186  and then to a Transmitting Antenna  188 . 
     A local Cable Head End  166  has a plurality of Satellite Dishes  190  and Antennas  192  for receiving signals from a plurality of Network Head Ends  160  and Affiliates  164 . The received signal from each of the Satellite Dishes and Antennas is provided to respective inputs of Multi-channel Inserter  194 , which can also insert data into the VBI of a received signal. The multi-channel output from the Inserter  194  is amplified in Amplifier  196  and provided over a Cable  197  to individual Receivers  168 . Alternatively, the Receivers  168  could receive the broadcast information via antennas or satellite receivers. 
     Note that the Central Site  22  of FIG. 1 may be located at the Network Head End  160 , Affiliate  164 , or Cable Head End  166  and be integral with the components depicted in FIG. 3 as Network Head End, Affiliate, and Cable Head End, respectively. Alternatively, the Central Site  22  is located at a location different than the Network Head End, Affiliate, or Cable Head End. In either case, the operator of the Central Site  22  provides information regarding PPV events and home shopping products to be inserted into the VBI of the television signal during broadcast of related advertising segments. 
     Caption data decoding used in the data transmission system is further described in the following specifications, which are hereby incorporated by reference herein: Title 47, Code of Federal Regulations (CFR), Part 15, as amended by GEN. Docket No. 91-1; FCC 91-119; “CLOSED CAPTION DECODER REQUIREMENTS FOR THE TELEVISION RECEIVERS”; Title 47, CFR Part 73.682(a)(22), Caption Transmission format; Title 47, CFR Part 73.699, FIG. 6; “TELEVISION SYNCHRONIZING WAVE FORM”; Title 47 CFR Part 73.699, FIG. 17 a ; “LINE 21, FIELD 1 DATA SIGNAL FORMAT”; and PBS Engineering Report No. E-7709-C, “TELEVISION CAPTIONING FOR THE DEAF: SIGNAL AND DISPLAY SPECIFICATIONS.” 
     The extended data services is further described in the  Recommended Practice for Line  21  Data Service,  Electronics Industries Association, EIA-608 (drafts Oct. 12, 1992 and Jun. 17, 1993), the subject matter of which is hereby incorporated by reference. Under this standard, additional data is provided in line  21 , field  2  of the vertical blanking interval. This additional data includes two closed captioning fields, two text mode fields and the extended data services. The extended data includes, among other information, program name, program length, length into show, channel number, network affiliation, station call letters, universal coordinated time (UCT), time zone, and daylight savings time usage. Upstream at the Network Head End  160 , the network inserts the program name, the length of the show, the length into the show, the network affiliation, and the UCT. Downstream at the Affiliate  164 , the Affiliate inserts the channel number, the time zone, the daylight savings time usage and program names. The Network Head End inserts the data that does not differ for the different Affiliates. PPV event and home shopping product data may be inserted by either the Network Head End  160 , the Affiliate  164 , or the local Cable Head End  166 . 
     The data may be manually entered from a local Terminal  198 . The Terminal  198  may be used to build, recall, or edit information to be used as insertion data. The Terminal  198  typically includes a computer. In addition, Modem  199  may be used to provide data to Inserter  172 . The data may be provided manually or automatically from remote sites, such as the Central Site  22 . The output of the Inserter  172  is a composite television signal including the PPV event and home shopping data. 
     Referring back to FIG. 1, the viewer uses Remote Control Unit  24  to send commands to the Television  10  over an infrared link  26 . Remote Control Unit  24  includes BUY button  28  which is pushed by the viewer to initiate a purchase transaction. Television  10  receives the BUY command and communicates the request to the DTMF Circuit  14 . 
     FIG. 4 is a block diagram illustrating the main components of the Television  10  and Remote Control Unit  24 . Television  10  is capable of decoding the vertical blanking interval lines and using the embedded information to support PPV and home shopping applications. The Television has a Tuner  200  which receives the Television Signal  12  from either an antenna, a cable box, a satellite receiver, or other signal transmission medium. A VBI Decoder  202  is coupled to the output of the Tuner  200 . A Microprocessor  204 , which implements the Television control logic, receives the output of the VBI Decoder  202 . The Microprocessor controls the output of the Television Signal  12  to Monitor  206  for viewing by a viewer. The Microprocessor  204  also communicates with the DTMF Circuit via output Line  134  and input Line  126 . The Microprocessor executes programming instructions to support PPV, home shopping, and other applications. Infrared Receiver “R”  208  receives commands and data from Remote Control Unit  24 , which are then forwarded to Microprocessor  204  for processing. 
     Remote Control Unit  24  includes an Infrared Transmitter “T”  210  to send commands and data to Infrared Receiver  208 . Microprocessor  212  controls the operation of the Remote Control Unit by accepting input data from Keypad  214 , displaying output data on Liquid Crystal Display (LCD)  216 , and sending commands and data to the Infrared Transmitter  210  for transmission to the Television  10 . Included in the Keypad  214  are keys for selecting specific functions relating to PPV or home shopping applications, such as a “BUY” key, or keys indicating PPV programs or television channels. 
     In the preferred embodiment of the present invention, program-related information that is embedded in the vertical blanking interval lines of the Television Signal  12  includes a telephone number related to the information that is being broadcast. The telephone number in the program-related information is extracted from the Television Signal by the VBI Decoder  202  and sent to the DTMF Circuit  14  by the Microprocessor  204  for initiating a telephone connection. 
     Note that the difference between the present invention and the concept wherein a remote control unit is also a telephone is the synchronization and organization of data in the Television  10 , which itself may be simultaneously receiving data from the Television Signal  12 . This synchronization of data allows the viewer to respond to certain stored or time-sensitive information displayed on the Television (supplied to the Television in either digital or analog form) by pressing keys on the Remote Control Unit  24 . The Television  10  then combines the received command information with PPV program or product identification data and telephone numbers for transmission to the Cordless Telephone Base Unit  16  for forwarding to the Central Site  22  for processing. 
     FIG. 5 is a block diagram of an alternate embodiment of the present invention. In this embodiment, the DTMF Circuit  14  resides in the Remote Control Unit  24  instead of the Television  10 . Two-way communication is now needed between the Television  10  and the Remote Control Unit  24  so that decoded VBI data (such as telephone number and product information) can be forwarded to the Remote Control Unit  24  for processing by the Microprocessor in the Remote Control Unit. In this instance, it is important to identify what PPV program the viewer is purchasing. Separate keys (not shown) can be included in the Remote Control Unit  24  which are labeled with names of PPV programs or services (such as HBO, SHOWTIME, ESPN, etc.). In order to select a PPV program, the viewer presses the key representing a particular service, followed by the BUY key  28 . As in FIG. 1, the DTMF Circuit  14  may also include the capability for receiving data. However, since no voice transmission or reception is needed, the circuitry required to implement DTMF transmission and receptions is smaller and simpler than in conventional cordless telephone handsets. 
     FIG. 6 is a flow chart illustrating the high level operational steps of the present invention. After Start Step  300 , the Television  10  receives data regarding an advertising segment in the vertical blanking interval lines of the Television Signal  12  at Step  302 . For example, the advertising segment could contain a preview of an upcoming PPV event or product for sale in a home shopping situation. The embedded data includes a program or product identifier, and the telephone number of the PPV service provider or seller. The advertising segment contains the price of the PPV event or product so the viewer can make an informed decision on whether to purchase the product or the right to view the advertised PPV event. The viewer sees the advertising segment displayed on the Television at Step  304 , and is prompted, either audibly or visually, to respond. If the viewer decides to buy, at Step  306  the viewer pushes the BUY button  28  on the viewer&#39;s Remote Control Unit  24 . Next, at Step  308 , the Remote Control Unit  24  sends a signal via Infrared Transmitter  210  to the Infrared Receiver  208  located in the Television  10 . The signal includes the unique code for the BUY button, thereby instructing the Microprocessor  204  in the Television that the viewer wants to buy the currently advertised PPV event or product. 
     At Step  310 , the Microprocessor  204  combines the received BUY command with identification information of the viewer (which is stored in memory resident in the Microprocessor  204  during initialization of the Television  10 ) and the embedded advertising data discussed above. The viewer identification information may include the viewer&#39;s credit card information for payment and billing purposes. At Step  312 , the Cordless Telephone Base Unit  16  initiates the telephone call, connecting to the Central Site identified by the telephone number passed to Cordless Telephone Base Unit by the DTMF Circuit  14 . The Microprocessor  204  of the Television  10  then sends the BUY command to the Cordless Telephone Base Unit  16  via DTMF Circuit  14  at Step  313 . After the connection is established, the BUY command information is transferred to the Central Site at Step  314 . At Step  316 , the Central Site processes the BUY command and sends a confirmation message back to the Cordless Telephone Base Unit  16 . Processing of the BUY command could include enabling the viewer to receive access to the scheduled PPV event or accepting an order for an advertised product. The Cordless Telephone Base Unit at Step  318  relays the confirmation message to the Television via the DTMF Circuit  14  and the Microprocessor  204 . Next, at Step  320 , the Microprocessor  204  of the Television  10  stores part or all of the confirmation message and displays part or all of the confirmation message on the Monitor  206 . The viewer thus gets immediate feedback that the viewer&#39;s order for the event or product has been accepted. The confirmation message could also include information related to the PPV event or product such as the planned delivery date of the product. The Television then concludes the telephone call at Step  322  and processing ends at End Step  324 . 
     In another preferred embodiment of the invention, the viewer may order a program or product which is not currently being advertised by accessing a series of menus. The Microprocessor  204  includes a Memory  205  (FIG. 4) for storing a telephone directory which includes a list of names for service providers, e.g., PPV program providers and home shopping channels, and a telephone number corresponding to each service provider. The Microprocessor  204  may also store in the Memory  205  additional viewer identification information such as the viewer&#39;s account number for a particular service provider. 
     Information regarding the service providers, including their names and associated telephone numbers, are transmitted by the Central Site  22  in the VBI and received by the Microprocessor  204 . The Microprocessor creates a list of available service providers as they are received and assigns each service provider a Provider Reference Number  400  which is stored in the Memory  205 . The service provider information may be transmitted by the cable company or by the individual service providers. The telephone directory may expand over time as information for new service providers are received by the Microprocessor. 
     The Microprocessor  204  displays the list of service provider names with the associated Provider Reference Number in a Main Menu  402 , as shown in FIG. 7, in response to the viewer pushing a MENU button provided on Keypad  214 . 
     The Central Site  22  also transmits in the VBI a list of available items currently being offered by each service provider. Each item is identified by an associated Item Reference Number  404 . Once in the Main Menu  402  and in response to the viewer pushing a number identifying one of the listed service providers, the Microprocessor displays on the Television  10  a Catalog Display  406  which includes a list of items available from that particular service provider and the corresponding Item Reference Number for each item, as shown in FIG.  8 . 
     The viewer selects an item by pressing a button on the Keypad  214  corresponding to the Item Reference Number  404  for that item. Consequently, the Microprocessor  204  performs the steps  310  to End Step  324 , illustrated in FIG. 6, but processes the Item Reference Number and stored service provider information rather than the BUY command and embedded advertising information to form a purchase command. 
     For example, if the viewer pushes the “1” button on the Keypad  214  while the Main Menu of FIG. 7 is displayed, the Microprocessor  204  will display the catalog of FIG. 8 on the Television  10 . If the viewer then presses the “2” button, the Microprocessor will initiate the steps for ordering the PPV program “Blade Runner.” 
     In an alternate preferred embodiment, the Microprocessor controls the DTMF Circuit to initiate a telephone call to a service provider immediately after it is selected from the Main Menu, but before an item is selected. In this manner, the time required to connect to the Central Site  22  after the order is placed is reduced. 
     In a further alternate preferred embodiment, the step of displaying and selecting a service provider from the Main Menu  402  can be eliminated from the purchasing sequence. According to this embodiment, the Microprocessor  204  displays the Catalog Display  406  for a particular service provider in response to the viewer pushing a LIST button on the Keypad  214  while the Television  10  is tuned to that service provider&#39;s broadcast, e.g., a home shopping channel program or an advertisement for a PPV program provider. In response to the viewer selecting an item, the Microprocessor combines the Item Reference Number with the service provider information embedded in the VBI and the stored viewer identification information to form a purchase command. 
     Many telephone lines include a call waiting feature which may interfere with the connection between the Central Site  22  and the Cordless Telephone Base Unit if a telephone call is incoming during the connection. According to further embodiment of the invention, the DTMF Circuit may be provided with the capability to identify an incoming call, and in cooperation with the Microprocessor, automatically disconnect from the Central Site  22  and reconnect when the line is not busy, thereby allowing the incoming call to be received by the Cordless Telephone Base Unit. Alternatively, the Microprocessor  204  may deactivate the call waiting feature by instructing the DTMF Circuit to transmit the appropriate call waiting disable code, such as “*70,” when transmitting the tone signals to the Cordless Telephone Base Unit at the initiation of each telephone call to the Central Site  22 . Preferably, the Microprocessor  204  displays prompts for the viewer during the initial setup of the Television  10  to enable a selected one of these alternatives. 
     In yet another embodiment, the Microprocessor  204  displays a Status Display  408  on the Television  10  while the Cordless Telephone Base Unit is connected to the Central Site  22  to inform the viewer of the status of the telephone connection and purchase order, as shown in FIG.  9 . Preferably, the Status Display includes a Message  410  identifying the status of the connection, such as “Dialing”, “Connecting”, “Order Confirmed”, or “Incoming Call”, as well as a Graphical Representation  412  of the status of the telephone order. 
     The invention has been described in its presently contemplated best mode, and it is clear that it is susceptible to various modifications, modes of operation and embodiments, all within the ability and skill of those skilled in the art and without the exercise of further inventive activity. Accordingly, what is intended to be protected by Letters Patent is set forth in the appended claims.