Tornado warning system

A pager receiver based system provides a method and an apparatus for receiving and detecting a tornado alert from the National Weather Service, determining the region to which the alert applies, and broadcasting an alert signal to a plurality of pager receivers, all programmed with the same pager number, within that region.

FIELD OF THE INVENTION
 The present invention relates generally to the field of tornado warning
 systems and, more particularly, to a dedicated pager system for providing
 tornado alerts, as well as a method of providing a distributed warning
 signal on a county-by-county basis (or other geographically defined grid
 system) using a paging system.
 BACKGROUND OF THE INVENTION
 Tone activated alert receivers are well known and are regularly used by
 emergency agencies including fire, police, ambulance, and rescue services.
 The National Weather Service (NWS) transmits an alert signal to activate
 commonly available weather alert receivers to warn of impending severe and
 potentially life threatening weather such as tornadoes, thunderstorms,
 floods, and blizzards. Known receivers can be set to issue a siren, flash
 an LED, and/or announce the voice weather alert message in response to
 receiving and decoding an alert signal.
 The NWS and emergency agencies broadcast a digital code as a header
 preceding each alert message. This digital header usually contains the
 type of warning, the effective time and expiration time of the warning and
 the areas effected. Although the type of the warning can be obtained
 through decoding the header, it has been found that most of the effected
 public doesn't feel a compelling need for all of the information contained
 in the alert message, or even all the information contained in just the
 header. What the public wants is an alert of an impending severe weather
 condition, such as a tornado, that is specifically directed to them, in
 sufficient time to take evasive action.
 Such warnings are often extremely time critical. Warnings must
 automatically be received by the ultimate end user, preferably on a
 dedicated system that will not be interfered with by other communications
 channels.
 U.S. Pat. No. 5,681,852 to Gropper describes a capable system which
 provides an alert receiver interface. The receiver automatically detects
 the issuance of an emergency message broadcast on a radio channel, or on
 another communication system. The system records that alert message into
 the receiver with an audible day and time stamp for later playback. The
 system also provides an interface between the alert receiver and other
 communications systems, including paging system, whereby an alert message,
 or an alarm tone, is automatically relayed and repeated on the other
 communication system. The system also teaches selectively activating
 another communication system for only those alert messages of specific
 concern to users of the other communications system. In that mode, the
 alert receiver interface can be set by a user for specific needs such as
 to detect a fire company's alert signal on a public service radio channel
 and then go through the recording, day, and time stamp and playback
 sequences.
 While the system described in the '852 is a very capable system, recent
 tragedies, such as that in Oklahoma City, indicate that a broadly
 available alert warning system is still badly needed. Such a system should
 be dedicated to a specific need, without the requirement of being selected
 by a user. Further, the system should eliminate the mystery of the known
 complex systems, and be readily acceptable in the market.
 Sales figures show that consumers today readily accept pagers and smoke
 detectors. Consequently, an alert warning system preferably should extend
 the already widely accepted pager and smoke detector systems to provide an
 audible early warning of a tornado.
 SUMMARY OF THE INVENTION
 This invention teaches a method and apparatus for receiving and detecting a
 tornado alert from the National Weather Service, determining the region to
 which the alert applies, and broadcasting an alert signal to a plurality
 of pager receivers, all with the same pager number, within that region.
 Weather alerts are commonly issued today on a county-by-county basis, and
 it is anticipated that advancing technology will soon permit the NWS to
 issue such alerts that are broken down into an even smaller area than a
 county. The present invention anticipates such advancements within the
 scope of the present invention.
 An object of the present invention is to create a dedicated, simple, and
 reliable tornado alert system. The system is preferably housed within the
 same enclosure as a common smoke detector, or in an enclosure that mimics
 but is distinguishable from a common smoke detector.
 In the system of the present invention, a monitoring station continuously
 monitors broadcasts from the National Weather Service. All but tornado
 alerts are eliminated, so that the system only selects tornado alerts
 which are broadcast. The system next determines the region to which the
 alert applies, generally today specifying one or more counties. For each
 county (or other smaller region), the system broadcasts one, predetermined
 pager number, one pager number per region. Within the region are installed
 a plurality of pager receivers, each pager receiver installed within its
 own previously described enclosure. Thus, the tornado alert may be
 received by thousands of pager receivers, each assigned the same pager
 number, and all within the specified geographic area. That way, if a pager
 receiver installed within the system of this invention receives a number
 directed to it, the receiver is within the region to which the tornado
 alert applies. The pager receiver then activates a distinctive audible
 alert which is readily distinguishable from a smoke alarm.
 The system of this invention is adapted to use well know pager receivers,
 but is modified to emit an alarm that is distinguishable from other
 alarms, such as smoke alarms, and is further modified to emit an alarm
 that is loud enough to awaken a soundly sleeping person.
 These and other features and objects of this invention will be apparent to
 those skilled in the art from a review of the following detailed
 description and the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS
 FIG. 1 depicts a schematic of the tornado alert system of this invention.
 As previously described, the National Weather Service (NWS) 10 constantly
 monitors weather conditions and, in the event of a detection or a report
 of a tornado being sighted, or other dangerous weather condition, issues
 an alert. The alert may contain a great deal of information of interest,
 but the only information pertinent to the present invention is that the
 condition is a tornado reported to have touched down and its location.
 The alert is transmitted from the NWS 10 via an antenna 12 as a broadcast
 signal 14. The broadcast signal 14 is received by an antenna 16, located
 at a central monitor 18, a feature of the present invention. The monitor
 includes a number of features, shown in more detail in FIG. 3. The monitor
 filters out all broadcast signals from the NWS except for those indicating
 a tornado. From the tornado alert, the monitor determines the location of
 the tornado. Generally, the tornado alert indicates what county the
 tornado has been spotted in. The particular county determines which of a
 set of pager receivers (FIG. 3) are to receive a pager alert signal.
 The monitor 18 develops the pager alert signal, and transmits this pager
 alert signal via an antenna 20, which may be a conventional pager antenna.
 The antenna 20 transmits the pager alert signal as a signal 22, which is
 received in all of the pager receivers in the appropriate county which are
 enabled with the present invention, shown in FIG. 1 as county 24 or 26. It
 should be understood that the signal from the antenna 20 may be directed
 to a satellite in the conventional manner, so that the invention
 potentially covers the entire world.
 It should also be recognized that all of the pager receivers enabled with
 the present invention in one particular county are programmed with the
 same pager number, which is different than any other county. Thus, when a
 pager receiver in the system is activated, the user knows for a certainty
 that a tornado has been reported or sighted in the county where the user
 is.
 FIG. 2 is a smaller scale map of a section of Texas. This drawing figure
 indicates that, if the NWS can pinpoint a tornado to a grid section which
 is only a portion of a county, such as one of portions 30, 32, 34, or 36,
 the present invention can accommodate that advancement in technology.
 Thus, if a user knows that he is in section 34, and his pager tornado
 alert system is activated, he knows that the tornado is within the region
 within the boundaries of portion 34.
 FIG. 3 shows additional details of the invention. As previously described,
 the monitor station 18 receives a signal 14 at an antenna 16. The received
 signal may comprise a flood warning, a fire alert, a tornado alert, or
 other disaster warning. The monitor station 18 receives all of these
 signals, but it includes a filter 40 to ignore all signals but those
 indicating a tornado warning.
 Alternatively, this portion of the invention may involve a human operator
 who continuously monitors the NWS and other broadcasts. The monitoring
 takes place at a workstation 70, which includes a CPU 72. An operator
 screens all of the announcements from the NWS or other weather reporting
 service and passes on only the tornado warning signals.
 The received signal 14 also includes a geographic indication of the
 location of the announced tornado. This information is packaged in the
 monitor station 18 in a transmitter section 42 as a simple pager signal.
 The pager signal is then transmitted by the antenna 20.
 Each of the users equipped with this invention includes an installed pager
 receiver 44, each having an antenna 45. The pager receiver 44 is mounted
 within a structure 46, which may be a residence, an office building, a
 church, or other building. Some of the structures 46 are located in county
 24, and some are located in county 26. Those within county 24 are all
 programmed with the same pager number. Those within county 26 are all
 programmed with the same pager number, but that pager number is different
 than those within county 24.
 FIG. 4 depicts a block diagram of a combination unit 50. The combination
 unit 50 includes a smoke detector 52 and the pager receiver 44. The
 combination unit is preferably powered from a standard 110V AC line
 current 54 which provides power to a power supply 56. The power supply 56
 is preferably provided with a battery backup 58. The power supply 56
 powers each of the smoke detector 52 and the pager receiver 44. In one
 sense, the smoke detector 52 is a "local" sensor, in that it is activated
 by a phenomenon within the structure 46, and the pager receiver 44 is a
 "remote" sensor, in that it is activated by a phenomenon outside the home.
 The system is easily adapted to other phenomena of interest, such as an
 intruder alert from the structure, and other phenomena from outside the
 structure to activate the combination unit.
 Upon activation, either the smoke detector 52 or the pager receiver 44
 generates an audible signal and the audible signal from the smoke detector
 is easily distinguishable from the audible signal of the pager receiver.
 Each should be loud enough to wake up a soundly sleeping person. The smoke
 detector 52 and the pager receiver 44 share a common speaker or enunciator
 60 for this purpose.
 In the preferred system arrangement, each user subscribes to the system for
 the service. The receiver 44 is installed in the structure, whether it is
 a home or other building, and the receiver 44 is provided with or without
 charge. In return the user pays a subscription fee with a minimum
 subscription term. This way, the user has a reliable, inexpensive tornado
 alert system, and the service provider can gauge the service fee to assure
 a profit.
 The principles, preferred embodiment, and mode of operation of the present
 invention have been described in the foregoing specification. This
 invention is not to be construed as limited to the particular forms
 disclosed, since these are regarded as illustrative rather than
 restrictive. Moreover, variations and changes may be made by those skilled
 in the art without departing from the spirit of the invention.