COMMUNICATION NETWORK

Abstract: A communication network advantageously uses existing broadcast channels (24, 32) to instruct remote receivers (16) and eventually use automatic dial-up capability (4) for forming a telephone communication link (26) with a central processing facility (20). The network is capable of providing many services from remote reading of meters (10, 12, 14) to electronic mail and electronic billing. The network is preferably shared by a number of large users (34, 36, 38) communicating with a host of subscribers (2).

Description: TITLE: COMMUNICATION NETWORK BACKGROUND OF THE INVENTION The present application relates to communication networks, and particularly to communication networks which use existing physical channels of communication which cooperatively form a new system for transfer of information in at least one, and preferably two, directions without the construction of additional physical communication channels or major upgrades to existing physical communication channels. The structure disclosed in this application has application for the automatic reading of various meters provided in homes, businesses, and institutions τ TM.,as well as in electronic mail,' electronic TELEX -type applications anc security systems, and other data communication applications, as out some examples. Various systems have been proposed for establishing a communication network between indiviαual subscribers and certain utilities, such as the water utility, the gas utility, or the electric utility, whereby the meter of the particular utility is read electronically and the reading forwarded to the utility electronically. To a large extent, many of these systems reouireC s telephone communication link being initiated by the utility causing the telephone within the subscribers' dwelling to be activated. Some arrangements Dlacec equipment before the telephone to recognize an incoming signal, however, these have not proven popular. The main problem with this system is that all phones in a house or dwelling are activated by the incoming call resulting in inconvenience to the subscriber. It has also been proposed to utilize existing cable television systems as a two way communication channel; however, owing to the high cost cf conversion from one-way to two-way, such systems have proven to αate only to be speculative. It has also been recocnizec tna it would be possible to again hard wire a further communication channel within a city or region which is in effect what has happened with the use .of TELEX systems.; however, the cost for doing this has been prohibitive in most cases. According to the present invention, a new utility or central processor or intermediary is proposed which would function in the manner of existing utilities for supplying the telephone services. This service would be particularly useful for the electrical utilities, water- utilities, gas utilities as prime examples, and could .also be used for electronic mail used by corporations anc individuals. Basically, a new communication utility can be established which uses existing communication channels without modification, thus avoiding the massive investment in additional equipment for existing corr-ur.icεticn systems or for new communication systems that has been proposed in prior art arrangements. In effect, according to the present application, this communication utility is possible and will work in a way very similar to a new wire based communication network without requiring the massiv.e investment for such a new communication network. According to the present invention, the communication system combines the communication capabilities of the telephone and broaocast mecia with the power of distributed micro-processor intelligence. This system requires a receiver installed on the premises of each subscriber which interfaces with various communication channels including the telephone communication channel and, in certain cases, a cable television outlet. The receiver is acapted tc continually monitor a broadcast signal either sent on the free air or over the cable TV network. In this way, the receiver monitors the broadcast signal checking for a ater cf its identification signal anc, upon matching its identification signal with a received signal, it initiates a telephone communication frorr the receiver tc tne central processing facility. In this way, the problems associatec with a telephone call being placed to the subscriber from the processing facility are avoided. SUMMARY OF THE INVENTION A communication network according to the present invention, comprises a plurality of receiving means in combination with a central processing facility. The central processing facility is adapted to receive and automatically answer incoming telephone calls and to senc out an instructing signal containing particular identification or address codes ano preferrably commanc signals mixed with, or superimposed on, a transmittec broadcast signal. Each of the receiving means has a particular address, and is tuned to the instructing signal. Each receiving means further includes means fcr determining whether the instructing signal contains the particular address of the receiving means. Processing means are associated with each receiving means anc activated by the receiving means upon receipt of the appropriately addressed instructing signal to execute a control action based on command data containeα in the instructing signal, for example, to determine the value of at least one predetermined function of a plurality of functions. This value or values is transmitted to the central processing facility by automatically placing a call to the central processing facility and transmitting a code identifying the subscriber and the value of the at least one predetermined function. The central processi g facility upon receipt of the transmitted coαeα signal processes the signal to, in general, combine it with cf-.er signals as required for subsequent transmission to predetermined parties. Although the present invention makes it possible to effectively provioe remote reading of varic--s rreterε in a home, business, or institution, it is alsc possible tc use this system for the relaying of information cetwee- * ' individual subscriber equipment over existing telephone lines by means of a process intermediary. In this arrangement, the communication system includes subscriber equipment activation means other than existing telephone lines, with each subscriber equipment continuously monitor a signal for a match with a predetermined instructing signal. The process intermediary includes means for storing information received by the process intermediary means for eventual transmission to one or more subscribers identified within the information. The process intermediary means includes means for processing the received signal to cause an instructing signal to be produced and transmitted to the identified subscriber over a non-telephone communication link and further incluoes means for transmitting the stored information over telephone lines when appropriately activatec by the identified subscriber equipment. Each subscriber equipment includes means for establishing a telephone communication link with the process intermediary anc includes means for identifying the subscriber to activate the process intermediary means after the communication link has been established and the subscriber iαentifiec. The subscriber equipment also includes means for receiving and recording the information addressed to the particular subscriber equipment. A process for a communication system having a host of individual subscriber stations, each having an addressed receiver and processor for identifying a non-telephone signal uniquely addressing the particular station, and means associated with the receiver fcr initiating a telephone communication link with a signal processing intermediary upon receiving and identifying the address associated with the receiver is taught. Tne process requires the signal process intεrmeciary tc communicate with an existing broaocast syster v-hicr. produces, acccrαing to its normal operation, a croaccast siαnal capable of beinc receiveo bv eac su--.scrit-.er station. The process intermediary transmits instructing signals through a communication link for simultaneous transmission with the broadcast signal and includes telephone answering means for completing the telephone communication link with the subscriber station. The process intermediary includes means for storing and processing information received from a subscriber station identifying at least one unique receiver which is one of said subscriber stations, and causing said means for transmitting to transmit the identifying signal and preferrably a command signal of the at least one receiver for simultaneous transmission with the broadcast signal. The means for processing causes transmission of such information to the identified subscriber station anc facilitates the receipt of such information from the identified subscriber station upon establishment of tne telephone communication link between the station and the signal process intermediary initiated by the subscriber station. The central processing intermediary according tc the present invention comprises means for automatically answering incoming telephone communication links from individual subscribers and establishing whether a signal is to be received from such subscriber for eventual transmission to others, or whether a previously receivec signal is to be transmitted to such subscriber. Means for recording received signals transmitted to the central processor from the subscriber stations over such telephone communication links is present, as well as means for processing each of the received signals tc extract the identification code of a further subscriber to which at least a portion of the signal is to be sent. This extracted identification code is transmitted to a broadcast station for simultaneous transmission with a broadcast signal by means for transmitting a signal whicn forms part of the central processor. The central processor upon receipt of incoming telephone communicatio n links at least partially determines whether the subscriber is to originate, a.signal for transmission to others or is to receive a signal transmitted to the central processor by another subscriber. Once this has been determined, the central processor selects the appropriate channel for processing of the signal. A subscriber station for use in the communication network comprises means for establishing a telephone communication link with a central processor in preparation for the receipt of a signal from or the transmission of a signal to the central processor, tuning means for receiving a signal superimposed on a broadcast signal, means for comparing the received signal with a predetermined code peculiar to the subscriber station, control means for actuating the means for establishing a telephone communication link when a match between the received signal and the predetermined code is found, means for identifying the subscriber station to the central processor when the communication link has been completed, means for receiving and recording a signal originating from the central processor if the control means establishes the communication link, and means for selectively transmitting a signal to the central processor over a telephone communication link for, in general, eventual transmission to another party or subscriber. BRIEF DESCRIPTION OF THE DRAWINGS Preferred embodiments of the invention are founc in the drawings wherein; Figure 1 is an overview of how the communication system connects various subscribers and each subscriber with one of several large utilities. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The schematic of the communication network is shown in Figure 1 and includes a plurality cf subscriber stations generally shown as 2, which are linκεc tc ε central processing intermediary generally shown as 20 via telephone modems 4 and the non-dedicated telephone lines 24. Each subscriber station 2 includes an input means, in this case the antenna 6, for receiving the free air communication broadcast generally shown as 32. It can be appreciated that the antenna 6 could be replaced with a connection to a broadcast carried over a cable network as but one alternative. Each station includes a number of input/output channels generally designated as 8 for allowing connection to the remotely readable gas, water and electricity meters generally designated 10, 12 and 14 respectively. In addition, a hot water heater 19 or otner interruptible load is connected to the receiver/processor 16 in a manner to allow interruption of the power supply to the hot water heater or other load to effect load shedding as will be discussed subsequently. Central processing intermediary 20 is a central computer with the capability of automatically answering various telephone signals conducted over the normal non-dedicated telephone lines. The automatic answer lines are generally designated as 22. The central processing intermediary 20 is also connected to a radio station 28 via the transmission line 26 to effect transmission of an instructing signal to the radio station 26. Tne instructing signal at least identifies the adcress code of desired subscriber stations, with this instructing signal being superimposed on the normal broadcast signal eventually received by the antennas 6. The receiver processor 16, of each subscriber station 2, continuously monitors the instructing signal, and when a matcn between the particular address of the receiver/processor 16 anc the instructing signal is achieved, certain functions will be carried out by the receiver/processor. Preferrably command coαes are also trans ittec wit the address codes such that the receiver/proceεscr 16 carries out the demanded functions generally in preparation fcr communicating with the central process 2C. Therefore, in effect, the broadcast signal 32 which includes the address signals, is used as an outbound link to identify the particular subscriber stations that are to carry out a particular function such as meter reading. In this case, the instructing signal would actuate certain receiver/processors 16 which would then determine the various values of meters 10, 12 and 14. These values av already be stored in memory of the receiver/processor 16 if the signals from the meters are continuously fee to tne receiver/processor 16. The receiver/processor 16 via the telephone modem 4 and an automatic dial-up capability places an outgoing telephone call to the central process intermediary 20, whereafter identification of the subscriber station and the various readings will be transmitted. The central process intermediary 20 wculc record these values and, preferrably, process them with other data received from subscriber stations for appropriate distribution to the utilities such as electrical utility 34, gas utility 36 and water utility 38 which can be electronically connected to the central process intermediary via dedicated or non-dedicateα communication lines 37 or may be connected in a conventional manner such as by mail. Obviously, the electronic communication is preferrec, anc will allov. more rapid invoicing by the various utilities. In addition, other institution type users 39 of the system are shown and include governments, banks, brokers, newspapers, advertisers, security agencies, ticket agencies, credit card companies, data base services, market survey firms etc., who desire electronic communication with subscribers. These users may nave a dedicated or non-dedicated connection to the central process intermediary 20 and may cr may not reouire two way communication. This group woulo also "subscribe" tc the system but because of its particular purpose, tnis group has been separately identifieo. These other users 39, may require additional eαuipment 18 at eacn sutscricer static for functions such as information display, printing, entering, editing, storage, and processing. This equipment may include a printer, display, keyboard, storage means, and computer system, among other devices. It is also possible to use this communication system for other functions, such as load shedding which will be discussed with respect to interruptible loads such as the hot water heater 19. It is well known that the electrical utility must operate within fairly rigid maximum load requirements and pay substantial penalties for exceeding the maximum. In order to provide them with control or at least some control over the total demand for electrical power, certain interruptible appliances within individual premises can be automatically disconnected for a short period of time to thereby reduce the peak load. This is true of hot water heaters and central air conditioners, and water heater 19 has been connected with the receiver/processor 16 anc upon an appropriate signal being transmitted to the receiver/processor 16, the power supply of the hot water tank can be temporarily interrupted as requireα. Many advantages are possible by having a central process interemdiary which effectively connects inαividual subscribers with individual utilities anc otner institutional users. Centralizeα meter reading for example, becomes an economic reality. In addition, the basic equipment can be added to make possible electronic mail and electronic billing as additional services. The communication network uses existing technology to allow the completion of a telephone communication link between the subscriber station and the central processing intermediary to be activated by the subscriber station upon receipt of an instructing signal. Therefore, two existing communication channels, broadcast anc oial-up telephone, have been advantageously comoinec anc a central processing intermediary has been introcuceα to substantially reduce the capital cost associatec with eεcr station. Furthermore, secondary features such as load shedding and time of day billing can be accomplished providing further economic justification of the capital costs. The receiver/processor 16 includes logic such that the outgoing call to the central processing intermediary 20 only occurs when the telephone line is available and aborts the call in the event that another phone connected to the line is used. In this way, the normal operation of the telephone within the subscriber's premises remains unchanged and the subscriber station 2 only uses the line when not in use by the occupants. It can be appreciated that the various utilities can make requests of the central processing intermediary via the preferred direct communication lines 37, however, it is somewhat more effective if all meter readings are transferred from the subscriber station to the centτal. processor intermediary at the same point in time. Therefore, in order to transfer the required information to separate utilities, the central processing facility processes the information received from each subscriber and separates the same into the appropriate groups for distribution to the separate utilities. In this way, the central processing intermediary processes the information into a suitable form for use by other parties. Figure 1 up to this point, has been discussed with respect to the communication system for use in gathering information available at the subscriber's' premises and/or the possibility of load sheoding with respect to some appliances. It is also possible with this system to implement such services as dynamic time of oay billing for electrical power, time of day metering for electrical utilities, quality of service monitoring for electrical utilities, supply pressure monitoring for water and gas utilities, control of certain uses c water, on-line monitoring of fuel oil tank levels, oπ-iinε monitoring of gas leaks, inventory monitoring fcr industrial gas cylinders, inventory monitoring for vending machines and remote monitoring and control of distributee equipment. These services require the use of specializeα sensors of one sort or another, which result in an electrically-readable signal. The receiver/processor can be appropriately programmed to process these signals and provide a telephone communication link between the receiver/processor and the process intermediary. It is also possible in the present system to provide on-line monitoring of security alarms, on-line monitoring of smoκe and fire alarms, on-line monitoring of flood alarms, heat loss alarms, panic switch alarms, medical monitoring anc extended power failure alarms using the proposed communication network and suitable sensors. In order to provide electronic mail or messages, the receiver/processor of the subscriber would be providec with a terminal 18 for the presentation and entry of information and preferrably some processing means and memory capacity. In a more sophisticateo embodiment, it may utilize a personal computer as the terminal equipment 18 connected to receiver/processor 16 via line 17. A message would be originated at one subscriber station which thereafter would make the telephone communication link with the central processing intermediary 20 and transfer the desired message with the address cf the subscriber or user to whom the message is destined. The central processing intermediary 20 would then extract the address code of the subscriber or user to which the message is to be sent and have a signal procucec ana transmitted with the broadcast signal generally indicatec as 32. As all receiver/processors 16 are continuously monitoring the broadcast signal they woulo recognize their particular address ccce and, in this case, may recognize a further code indicating that a message was waiting for them at the central process intermediary. Tnε user c f that particular receiver/processor woulc have a message cr indication appearing thereon produced by hiε ~~ v- ~~ receiver/processor acknowledging a message haα been received by the central process intermediary. In this manual-type operation, the person would then complete a telephone communication link and have the message transmitted to him. It is also possible to automatically have this message transfered once the signal was receiveo by the station using its automatic dial-up capability for contacting the central process intermediary 20. Therefore, this arrangement again uses the existing dial-up telephone lines to effect a communication link between the subscriber and the central process intermediary while using the broadcast signal to alert tne subscriber eouipment of particular functions to be performed. The system described above provices an interactive subscriber service, which in effect, acts as a medium suitable for electronic mail, electronic delivery of invoices, electronic bill paying, electronic direct mail advertising, personalized real time information services, personlized notification services, electronic message services, shop at home services, home banking services, consumer surveys, plebisites, electronic purchase and delivery of tickets, ano home lottery selection and ticket delivery to mention only a few of tne possibilities. This full interactive subscriber service is accomplished without the creation of a new physical communication channel, by using the existing communication channels in a unique manner. Although various preferrec embodiments of tne present invention have been described herein in detail, it will be appreciated by those skilled in the art, that variations may be made thereto without departing from the spirit of the invention or the scope of the appenoec claims.

Claims: THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS: 1. A communication network comprising a plurality of receiving means in combination with a central processing facility; said central processing facility being adapted to receive and automatically answer incoming telephone calls and to produce an instructing signal containing particular address signals which is subsequently mixed with a transmitted broadcast signal; each of said receiving means has a particular address and is tuned to said instructing signal, each receiving means further includes means for αetermining whether said instructing signal contains tne particular address of the receiving means; and processing means associated with each receiving means and activated thereby upon receipt of the particular address signal to determine the state or value of at least one predetermined function of a plurality of functions and transmit the state of value to saic central processing facility by automatically placing a telephone call to said central processing facility and transmititng a coded signal identifying the subscriber ana the state or value of the at least one predetermined function; said central processing facility upon receipt of the transmitted coded signal processing the signal to combine them with other signals as required for subsequent transmission to predetermined parties. 2. A communication network as claimed in claim 1, wherein said known broadcast signal is a fiee air racic signal . 3. A communication network as claimed in claim 2, wherein said instructing signal is in a siαebanc of tne frequency range affordeo the raαio signal. 4. A communication network as claim c in clairr 1, wherein said central processing facility is ciiectlv connected to a broadcast facility to reduce delay in transmission of said instructing signal. 5. A communication' network as claimed in claim 2, wherein each of said receiving means includes a receiver tuned to the known broadcast signal. 6. A communication network as claimed in claim 1, wherein said central processing facility includes means for transmitting information to said subscribers, and saio receiving means includes means for receiving information transmitted thereto by said central processor, said central processing means causing a signal addressing said receiving means to be transmitted to initiate a telephone communication link between said receiving means ano said central processing means. 7. A communication system for relaying information between individual subscriber equipment over existing telephone lines by means of a process intermediary, said system including subscriber equipment activation means other than existing telephone lines with each subscriber equipment adapted to continuously monitor a broadcast signal for a predetermined identification signal; said process intermediary means including means for storing information received by the intermediary means for transmission to a subscriber icentifiec within the information, means for processing the receivec signal to cause an identifying signal to be produced and transmitted to said identified subscriber in the broadcast signal over a non-telephone communication link, and further including means for transmitting the stored information over telephone lines when appropriately activated by the identified subscriber equipment; each said subscriber equipment including means for establishing a telephone communication Iinκ with saic process intermediary and including means for icentifying the subscriber to said process intermeciary means upor. estaDlishing such telephone communication link to activate said process intermediary means, anc a storage r.ear.s for receiving and recording the information oestiπed for saio subscriber equipment. 8. A communication system as claimed in claim 7, wherein said means for processing includes a communication connection with an existing broadcast station and includes means for introducing said instructing signal into a known broadcast signal for the simultaneous broadcast thereof without disrupting said broadcast signal. 9. A communication network as claimed in claim 8, wherein each subscriber equipment includes processing means for selectively contacting said process intermediary only when said communication is not in use or about to be used by the subscriber. 10. A process for communication systems having a host of individual subscriber stations, each having an addressed receiver/processor for identifying a non-telephone signal uniquely addressing the particular receiver, and means associated with said receiver/processor for initiating a telephone communication link with a signal process intermediary upon receiving and identifying said addressing signal, said signal process intermediary including a communication link with an existing broaocast system which produces a broadcast signal capable of being received by said subscriber stations, means for transmitting instructing signals through said communication link for simultaneous transmission with the broadcast signal, telephone answering means for completing the telephone communication link with saiα subscriber stations, means for storing and processing information received from a subscriber station identifying at least one unique receiver which is one of said subscriber stations and causing said means for transmitting to transrit the instructing signal cf the at least one receiver for simultaneous transmission with the broaocast signal, said means for' processing causing transmission of such information to" said identified subscriber station . upon completion of the telephone communication link with said station and said signal process intermediary initiated by said subscriber station. 11. A process as claimed in claim 10, wherein said means for initiating a communication link includes a telephone modem and automatic dial up equipment. 12. A central processor which acts as an intermediary between subscribers for transferring information comprising means for automatically answering incoming telephone communication links from indiviαual subscribers and establishing whether a signal is to be received from such subscriber for storage or eventual transmission to others or whether a stored signal or previously receivec signal is to be trans ittec to such subscriber, means for storing received signals transmitted to said central processor from such subscribers over such telephone communication links, means for processing each of said receivec signals to extract the identification code of a further subscriber to which at least a portion of said signal is to be sent, means for transmitting a signal representative of the extracted identification codes to a broadcast station for simultaneous transmission with a broadcast signal, said central processor upon receipt of incoming telephone communication links at least partially determining whether such subscriber is to originate a signal for transmission to others or is to receive a signal transmitted to the central processor by another subscriber. 13. A subscriber station for use in a communication network comprising; means for establishing a telepnone communication link with a central processor in preparation for tne receipt of a signal from, or transmission of a signal to, the central processor, -tuning means for receiving a signal superimposed on a broadcast signal, -means for comparing the received signal with a predetermined code peculiar to the subscriber station, - control means for actuating said means for establishing a telephone communication link when a match between said received signal and said predetermined code is found, -means for identifying the subscriber station to the central processor when said communication link has been completed, -means for receiving ana recording a signal originating from the central processor if saic control means establishes said ccmmunication link, -and means for selectively transmitting ε signal to the central processor over a telephone communication link for eventual transmission to another party or subscriber. 14. A communication network as claimed in claim 1, wherein said broadcast signal is a television or radio signal . 15. A communication network as claimεc in claim 14, wherein said broadcast signal is a free air transmission. 16. In combination, a broadcast station which transmits a free air signal at a given frequency within a given frequency band containing side banos, and a communication network comprising a plurality of receiving means identified by an address code anc central processing facility; said central processing facility including means to receive and automatically answer incoming telephone calls, means to originate an instructing signal containing particular receiving means aαdress cooes in response to incoming telephone calls identifying said receiving means by address code, and means for incorporating saic accress codes in said broadcast station signal; each of saio receiving means having a particular•address cooe ano being tuned to said broadcast signal, each receiving means further including means for determining whether said broadcast signal contains the particular address code of the receiving means; and processing means associated with each receiving means and activated thereby upon determining said broadcast signal contains said receiving ' , means address code, said activated processsing means determining the state or value of at least one predetermined function of a plurality of functions, anc transmitting the state or value and an ioentifying cooe to said central processing facility by means of a non-dedicated telephone line in cooperation with means for automatically dialing a known telephone number cf saic central processing facility. 17. In combination as claimed in claim 16, wherein said instructing signal is transmitted in said broadcast signal in one of said side bands and said receiving means are tuned to said one of said side bands. 18. In combination as claimed in claim.16, wherein said communication network is adapted to transmit desired information between subscribers; said central processing facility including means for receiving anc storing information from an originating subscrioer, which is to be sent to an identified other subscriber, and causing a signal which includes the address code of the other subscriber to be broadcast with said broadcast signal; said coded signal when received by said other subscriber creating a signal to initiate a telephone communication between said receiving means cf the other subscriber and said central processing means for transmitting the receivec and stored information which originated from said originating subscriber. 19. In a communication system having a central processing facility and a number of subscrioer stations which are selectively activated by an instructing signal controlled by said central processing facility to accommodate exchange of information therebetween, the improvement comprising selectively activating said subscriber stations by means of a free air broadcast signal originating from a separate broadcast station which transmits said instructing signal with a broadcast signal it would otherwise transmit alone. 20. In a communication system as claimed in claim 19, wherein said instructing signal is transmitted in a frequency side band of the broadcast signal and said subscriber staticns are tuned to said frequency side banα. 21. A communication system for transmitting information originating from a receiving and transmitting station and destined for another receiving ano transmitting station over telecommunication channels comprising : a plurality of receiving and transmitting statidns, each having a unique address code, means for receiving a broadcast signal which can include address codes, means for determining whether the particular address code is contained within a receiveα broadcast signal, an automatic telephone dialer, means for actuating said automatic dialer when the address code is determined to be contained in said received broadcast signal, ano a telephone line associated with said telephone dialer, a central processing facility including means to receive and automatically answer incoming telephone communications and store information including address codes transmitted during such communications, means to create an instructing signal containing particular adcress codes and incorporate such address cooes in a broadcast signal, and a broadcast station which transmits sucn aocress codes to receiving ano transmitting stations, wherein information identifying the oestinec receiving and transmitting station is transrrittec from an originating station to saio central processing facility which incorporates the address code of the αestinec receiving and transmitting station in a broadcast signal which when received by said destined receiving and transmitting station determines the particular adαress code is included in the broadcast signal by said determining means and actuates said automatic telephone dialer completing a telephone communication with said central processing facility which upon identification of said particular receiving means transmits to said destine: receiving and transmitting station the information.

Inventors: GORDON ALASTAIR TAYLOR, GORDON, ALASTAIR, TAYLOR
Applicants: TAYLOR GORDON ALASTAIR, GORDON, ALASTAIR, TAYLOR
Application year: 1987
Main classification: H04M11
IPC codes: G08C17, G08C19, H04H1, H04H9, H04M11