Patent ID: 12193118

DETAILED DESCRIPTION

The present invention generally relates to a hybrid audible signal generator device, referred herein to as a signal generator1a, a tone system1zincluding the signal generator1a, and a method of programming and using the signal generator such as those used for first responder applications including fire/ems emergency medical services tone paging over public safety radio systems. The signal generator1ais highly programmable, capable of supporting all common signaling protocols currently in use, as well as the creation of custom protocols, in an audible signal range from 0.001 Hz to well over 20 KHz, with a precision of +/−0.01 Hz on average with programmable amplitude.

The signal generator1amay be configured to include a simple configurable direct-view user interface8that allows use by dispatchers without specialized training. The signal generator1aalso supports extensive event logging and remote accessibility, including over secure TCP/IP networks1nand secure serial links1c,1k.

The signal generator1amay include flexible output ports1h,1g,1b,1c,1cto simplify connection to a wide variety of radio apparatus. Use of a stable proven display7hand operator actuator technologies contributes to a long operating lifetime compared to costly contemporary touch-screen LCD displays such as found in smart phones and tablets.

The signal generator1amakes use of hybrid digital and analog techniques to generate an almost limitless selection of signal protocols for first responder alerting, while also supporting common ancillary signal formats used to transmit other alerting information, activate responder quarters lighting, release secure key lockers onboard responder vehicles, and other applications. The signal generator1ais controlled by a highly simplified user interface8that allows dispatchers to access the capabilities of the device without extensive training.

Configuration of the signal generator1ais made using a simple plain-text programming interface and a serial terminal, such as a laptop15or a dedicated terminal emulator (not illustrated) or other external connection. The signal generator configuration can also be “cloned” from another similar device, allowing for easy replication of configuration on multiple devices, such as for backup spares or for cross-agency coordination. The synergies of the combined control and signal cores allows for a highly reliable, highly capable, and low-cost first responder signal generator1athat can be used in many different applications. The invention can operate as a standalone signal generator1a, programmed to satisfy the signaling needs of a specific entity, or it can be used as a sub-component of much larger scale solution, including controlling multiple radio devices. As illustrated inFIG.1, the signal generator1amay be connected to the laptop15for access to the plain-text command line interface4a, as illustrated inFIG.4.

In addition to supporting customizable standard signal formats such as one-tone, two-tone, DTMF, Morse code, and other tone-out signal protocols, the signal generator1amay also support a complex recipient type. A complex recipient type allows the creation of custom tone-out signals that may contain multiple previously-programmed recipients. A complex recipient definition would allow, for example, combining several individual recipients, such as fire stations, into a single logical group accessed by pressing a single dispatch screen using the next or previous page buttons7dor7gand then the selection keys7b,7cand repeating as needed, followed by the send button7f.

Alternatively, for first responder entities with complicated alerting equipment applications, the complex recipient type may be used to assemble different signaling sequences together.FIG.10depicts an exemplary tone-out sequence that includes a two-tone signal, an eight-digit DTMF signal, and a single-tone that repeats three times. Each of the three sub-elements is programmed separately as a standalone recipient first. Then the complex recipient is programmed, and the three individual sub-element identities are inserted, forming the completed complex signal sequence.FIG.10only illustrates exemplary tones and any type of tone may be generated or combination thereof.

In certain instances, it may be desirable to not allow the individual sub-elements to be visible to a dispatcher or operator on the dispatcher screen or control panel8,11,14,1ror1m. The signal generator1aprovides a recipient attribute modifier3bthat allows the display to be suppressed. The recipient, normally displayed, thus will not appear on the dispatcher screen or control panel. Since the sub-elements do consume page memory space, a typical installation might locate the sub-elements on the very last page or pages of the signal generator's1anon-volatile memory2.

No currently available standalone signal generators are capable of mixed signal types being chained together easily to create complex signal sequences in the same manner as the present invention.

The signal generator is configured to provide direct control over the audible frequency generated with extreme precision (+/−0.01 Hz typically) as well as the amplitude (voltage) of the resultant signal delivered to the attached radio or transmission equipment12, using an audio signal conditioning element9, and connected through the radio interface control logic6and radio isolation interface10. Amplitude adjustment allows pre-compensation for non-linear frequency response of various communication networks, and can help improve reception clarity of certain first responder pager signaling protocols. Many first responder entities are implementing secure ESInet architectures, with dedicated fiber optic and wireless network segments isolated from the Internet to carry mission-critical public safety information. The signal generator1amay provide a way to interoperate with digital radio dispatch consoles, CAD systems, and other PSAP equipment over the ESInet or similar secure Ethernet network via the network interface11. The network interface11may implement a simple Application Programming Interface (API) allowing third-party entities to request specific operations, query configuration data, and initiate tone-out transmission remotely using industry standard protocols and plain-text queries.

The signal generator1aembraces a multitude of configuration and operator interface options and can be remotely directed over a network. The signal generator1agenerally uses a Microprocessor1, a Real-time Clock3, an EEPROM nonvolatile memory2, and a RAM memory (which may be internal to the Microprocessor1). A simple plain-text programming language, which allows complex tone encoding protocols to be implemented, and easily accommodates new custom tone sequences may be used. A master reference oscillator4may also be used which provides a highly stable frequency reference for the multi-channel direct synthesis core.

The present invention can easily accommodate flexible input-voltage power supply (vehicle battery, AC mains, other) via the regulated power supply13, and the Multi-Channel Direct Digital Synthesis signal generating core5may produce high-precision signals with selectable wave shape and frequency. The signal amplitude of individual single or dual-tone protocols may be adjustable to pre-compensate for non-linear frequency response of connected transmission equipment and networks. In addition, amplitude is easily programmable in the plain-text programming language.

Other considerations and benefits of the signal generator1ainclude amplification and galvanic isolation to protect connected radio equipment12. A galvanically isolated control for Push-To-Talk actuator interface10of connected radio equipment allows direct connection to existing off-the-shelf radio transceivers12with simple cabling10. An integrated operator interface8with a flexible illuminated alphanumeric display screen7hand with perimeter buttons7b,7c,7d,7e,7f, or7g, or equivalent user actuator, or touch-screen user buttons provides ease of use and simple operating engagement. The signal generator may also include a serial interface1b, and1c, an Ethernet network interface1g, or other desired network interfaces, whether hardwired or wireless. The signal generator1amay use an isolated network interoperability interface11to securely connect with other devices, including but not limited to a remote dispatcher screen14, which may be part of a CAD system, as discussed above. The regulated power supply13is also illustrated. The signal generator1amay include onboard diagnostics, a keyboard or a touchscreen or other input device, and may allow for button/key debouncing in hardware and software.

As stated above, the signal generator may allow for direct computation of frequency divisors to produce accuracy of +/−0.001 Hz over wide range of frequencies. Of course other frequency tolerances may be allowed so long as they meet specifications of the tone systems. The signal generator1amay include a software technique for generating complex waveforms such as DTMF, MF, Knox Sentralock, and telecom call progress and network tones (busy, off-hook, etc.) or any other sequences of tones. As illustrated inFIG.1, an audio signal conditioning and amplification module or device9may be included. The conditioning and amplification module or device9are connected with the radio interface control logic6to a radio isolation interface and PTT drivers10, which is in turn connected to the various radio transceivers “1p,” which may be UHF, VHF or any other frequency band desired.

In addition, the signal generator1amay include the ability to adjust waveform amplitudes and compensate for attenuation associated with increasing frequencies. This may be accomplished by the microprocessor module1or a separate module. In certain configurations, the signal generator1amay have the ability to record time/date information associated with specific signal or tone out requests by a dispatcher/operator, and/or output that information to another machine or device. The signal generator1amay even be configured to be able to produce summary reports of recorded event information, and even have the ability to search recorded event history by date, by event type, and other search criteria. Of course, secure operating code stored on non-volatile memory2that is strongly resistant to hacking and unauthorized alteration is desirable. As currently configured, the Internet connectivity is NOT required for licensing or updating, although it could be included.

As stated above, one huge benefit of the present invention of the signal generator1ais that it can concurrently control the operations of multiple connected radios. Regional or adjacent public safety agencies frequently use different radio frequency bands, such as VHF and UHF, for tone-outs. The signal generator1athrough the radio isolation interfaces and PTT drivers10, radio ports1h, and radio cables1oallow radios operating on different frequency bands to be concurrently connected to the signal generator1a. Since the appropriate radio channel associated with a recipient has already been programmed and stored in the non-volatile memory2, a dispatcher need not be concerned about which radio is being used to transmit the tone-out being requested. Upon pressing the dispatch screen8pushbutton for a specified recipient7i, the signal generator1arefers to the recipient configuration details stored in the non-volatile memory2to activate the appropriate radio transceiver1p. This allows multi-agency alerting to be handled from a single device on multiple radio bands which was never previously possible. Further, the signal generator1amay communicate interactively with a connected radio transceiver1pover the radio connection cable1oto select a particular radio frequency communication channel, effectively tuning the radio on demand. For example, as illustrated inFIG.5, Page1could contain a recipient with a particular VHF radio frequency channel of 155.8050 MHz, and another recipient with a UHF frequency of 423.0500 MHz. The signal generator will automatically select the correct radio for transmission based on the programmed recipient information stored in the non-volatile memory2. In the event of multiple recipients in the same radio frequency band but with differing communication channel frequencies, the signal generator may communicate with the radio to request the radio change the current operating frequency to the appropriate value.

The invention makes use of flexible operator control panel architecture8enabling a fixed set of buttons/keys7band7cto be labeled with different tone-out recipients7i, grouped in pages,5a,5b,5cand5das illustrated inFIG.5. Stored recipient pages5a,5b,5c, and5dcan be navigated by use of page navigation buttons/keys7dand7g. The invention allows the operator or administrator to arbitrarily assign a given tone-out such as the illustrated tone-out2ainFIG.2, to a recipient associated with a specific button/key selected from the selection buttons7bor7con a specific page, allowing grouping of tone-out recipients5fin a way that is meaningful and efficient for operator or Dispatcher use. For example, multiple apparatus or crew units from a single fire station might be grouped together on a single page, with other stations grouped on different pages, or other departments grouped on other pages.

The signal generator1aprovides a unique and special type of tone-out recipient format that allows multiple single recipient configurations to be assembled together in a sequence, which may be assigned to a button or key, such as a key selected from the keys in the group of keys7b. Such sequencing might be used to tone-out a group of fire stations or a group of individuals for a particular incident type, or for programming complex custom alerting signals assembled from several different signal types, such as a single tone followed by a DTMF tone sequence.

The system1z, including the signal generator1a, and the individual components, as well as the external components such as the radio transceivers1pand antennas1qwill now be discussed individually in detail.

The Microprocessor1or microprocessor module1executes operating system code instructions to implement the signal generator1afunctions, including control of multi-channel frequency synthesis core5, audio signal conditioning and amplification/gain module9, and interface functions, or parts1b,1c, and1gsuch as the illustrated serial ports1band1c, user interface control logic7, and network interoperability interface, illustrated as the Isolated Network Interoperability Interface and API11inFIG.1. It should be noted that while the signal generator1ais discussed as having the tones and recipients stored internally, it is possible to store these on an external device, such as the illustrated console terminal15, which can be part of or in communication with the Remote Dispatcher Screen14, CAD1r, or a third party integrated Digital Radio Console System1m. The microprocessor module1may also implement internal housekeeping functions such as storage and management of user-defined signal protocols, recipient tone configurations, event logging and communication with real time clock3and external reference clock, such as the illustrated satellite clock16.

The non-volatile memory module2provides storage for user-programmed signal protocols, recipient tone configurations, event logs, and device usage statistics and may be accessed by and is in communication with the microprocessor module1.

The real-time-clock module3includes a crystal oscillator or resonator and at least one on-board backup battery to maintain an accurate time-of-day clock reference for the device. The real-time-clock3can be manually corrected or automatically updated with information from an external clock reference16. It should be noted that the signal generator1amay use any type of time device or timer capable of providing accurate time intervals to allow accurate and precise tone generation.

The master reference oscillator module4is an extremely precise clock reference for the multi-channel frequency generator5. The master reference oscillator4is used to set the frequency of the tones shown inFIGS.2and10. Operating frequency of the master reference oscillator4is multiple orders of magnitude above the signal generator1aoutput frequency range, which specifically can be millions of times greater, allowing for precise division down to the configured output frequencies with very small error.

The multi-channel synthesis core/frequency generator module5divides the master reference oscillator clock4by a programmable divisor and uses the result as an input to a direct-digital-synthesis core that is part of the illustrated frequency generator5that produces the desired wave shape (sine, saw tooth, or square) output signal. At least two channels are required to produce multi-tone signals such as DTMF, MF, or CAMA. Users may program other custom protocols using their own multi-tone protocols. More specifically DTMF, MF, and CAMA are comprised of at least two simultaneous frequencies summed together, and as such need at least two channels to produce the multi-tone signals.

The radio interface control logic module6is under the control of the microprocessor1which selects which radio device will be receiving a Push-To-Talk signal and the resultant generated audio signal including the tone. Selection logic also assures that signal output only occurs when specifically requested by device user, and prevents accidental radio transmissions. Control logic also can be programmed to communicate with, typically serially, with external radio equipment1pthat supports serial communications. Such communications may allow for checking radio status or selecting a specific transmission channel frequency within the radio's band capability. By managing the radio settings, a single radio device could cover multiple agency transmission frequencies, within the same RF band, and multiple radios in different bands, under direct control of the signal generator device1a.

The user interface control logic module implements the keyboard matrix decoder functions and drives the multi-line optical display7ithat identifies keyboard or button7b,7cfunctions. Logic uses a key debounce function to prevent accidental key selection due to mechanical switch contact bounce, and provides multi-key lockout in the event that two or more keys7b,7care pressed simultaneously due to user error. As illustrated inFIG.1, the user interface control logic module7may receive instructions from a user using the user interface8on the signal generator, specifically the display7h(optional) and buttons7b,7cor any other compatible input device or item capable of providing reliable input with minimal errors. The user interface control log or module7may also receive instructions from external devices, such as the illustrated computer aided dispatch (CAD) system1r.

The Local Dispatcher Interface8generally includes integrated keyboard or buttons7b,7cand an optional optical display module7hthat faces device user or operator, such as a public safety dispatcher at a public safety answering point (“PSAP”). As stated above, the local or integrated dispatch interface8communicates with user interface control logic module7.

The audio signal conditioning and amplification module9is configured for signal conditioning sub-component sums of individual signals from the multi-channel synthesis core5, and permits programmable gain adjustments to individual channels independently under microprocessor1and user program control. Multi-tone frequencies are subject to non-linear attenuation, particularly at higher frequencies and receiving tone decoders in receivers at the far-end experience this phenomenon and may have difficulty accurately decoding the multi-tone signals illustrated inFIGS.2and10. The signal conditioning sub-component of the audio signal conditioning module9allows pre-compensation to be applied to generated signals before being sent to a non-linear transmission channel, thus correcting the signal that arrives at the far-end and assuring reliable reception and accurate decoding by the receiver, such as a pager. A non-linear transmission channel is one that has an amplitude characteristic that changes relative to frequency in a manner that is not flat or linear. Typical voice radio channels, for example, will attenuate the input audio signal more as the frequency increases beyond a certain point. Such attenuation may not affect human speech intelligibility much, but it can significantly impact accurate transmission of signal tones. This frequency-dependent attenuation effect can be reduced or eliminated by pre-compensation, or intentionally sending the higher frequency signals at increased amplitude. By increasing the input amplitude of higher frequency signals, the resultant received signal at the far end will be at the correct amplitude, as the increase at input cancels the attenuation during transmission.

The radio isolation interface and PTT drivers module provides an isolation interface that allows safe connection of the signal generator1ato external radio transmission equipment, such as the illustrated transceiver1pand antennas1q, while providing galvanic isolation between the signal generator1aand the external equipment1o,1p, and1q.

The isolation is desired to reduce audible and radio frequency noise emissions, and to prevent unexpected radio operations. Push-To-Talk (PTT) control of a radio requires completing an external circuit to the attached radio transmission equipment by closure of a wire pair. This function is achieved with the use of a relay or equivalent semiconductor device having high off-state resistance. The signal generator1ais configured to work with and interface with almost any type of radio equipment.

The isolated network interoperability interface module11allows interoperability with external devices such as the illustrated devices14,1mand1rinFIG.1, and the interface subcomponent implements a basic set of TCP/IP protocols to permit communication between the signal generator device and external devices over a secure TCP/IP network such as an ESInet. Such secure networks are increasingly common in Public Safety Answering Point (PSAP) facilities. Typical communications between the signal generator1aand external equipment might include an integrated radio communications console at a central dispatch center remotely requesting specified recipient tone sequences to be generated and transmitted at a radio tower site miles away.

The connected radio transceivers1pare external radio transmission equipment, commercially available with multi-pin control connectors, and connect to the signal generator1avia a cable1o. One or more radios1pmay be connected in this manner. Radios1pmay operate in different frequency bands, such as VHF or UHF, and may be analog or digital or hybrid. A central dispatch center that provides tone-out signaling to multiple agencies might need to transmit certain signals on a VHF frequency and other signals on a UHF frequency. Multiple radios1pmay thus be connected simultaneously, and the signal generator1a, through the radio interface control logic6chooses which radios1preceives which signals. As illustrated inFIG.1, more than the two discussed UHF, VHF radio transceivers1pand antennas1qmay be included.

The regulated power supply13may be any suitable power supply sub-component that accepts main voltage, in fixed applications, or battery voltage, in mobile applications, or even some combination thereof and produces stable logic and analog signal processing sub-component supplies.

The remote dispatcher screen14may be connected via a secure network, such as an ESInet, the operator functions typically available on the Local Dispatcher Screen8can be made available remotely, such as on a hardware control panel or implemented in software as part of an integrated radio dispatch console, which may communicate with the Application Program Interface (API) in the isolated network interface.

The console terminal15is an external device that may be connected, such as a laptop, text terminal, or other readout device with a keyboard or other input device capable of communicating, such as through industry-standard RS232 serial communications as exemplary illustrated inFIG.1, and allows direct command-line access to the operating system software executing on the microprocessor1. Such command-line access might be used during configuration of tone recipients or viewing of tone-out events stored in non-volatile memory2. Please note that the illustrated remote dispatching screens consoles, digital radio systems and CAD systems may also be configured or programmed to perform some or all of these functions.

The External Satellite Clock16illustrated inFIG.1is an external time clock reference which may be connected via industry-standard serial protocol to the signal generator device for the purposes of synchronizing the internal Real Time Clock module3to a global time standard such as UTC via GPS. Please note any external clock may be used and this is not required, or the system time may be manually set or synchronized to a time reference provided by the remote dispatch systems14,1ror third party systems1m.

A typical two-tone audio signal sequence oscillogram and sub-elements output of the signal generator1ais illustrated inFIG.2. The specific components of the tone2awill be discussed in more detail below. The tone2ais an exemplary and typical two-tone tone-out signal transmission sequence comprising approximately 4200 milliseconds elapsed time. Time may vary due to arbitrary lengths of Prefix2band Suffix2f. The Prefix.2bis the time between transmitter initiation2ivia Push-To-Talk activation of radio, and the beginning of the first audible frequency2g. The Duration1or first location2gof a two party exemplary tone2ais the time duration of the first audible frequency2g, in seconds. All times and illustrated frequencies are exemplary and may vary in size, shape, frequency and duration. The great beauty of multiple tone systems is the wide variety of tones they may initiate using only minor variations to the time and frequency.

The Suffix2dis silent time between end of first audible frequency2gand the second audible frequency2h, in milliseconds. In this particular example, the programmed suffix time is zero milliseconds, so there is no silence gap between the two audible tones and the immediate switch without gap is clearly illustrated. The Duration2or second duration is the time duration of the second audible frequency2h, in milliseconds. The second frequency2his generally different than first frequency2gto provide the two tone system. The Suffix2for end suffix or second suffix illustrated inFIG.2is the silent time between end of second audible signal2hand termination of transmission2jby deactivating Push-To-Talk control of radio. More than two suffixes may be used on more complicated tones.

The Frequency1or first frequency2gis the first audible frequency signal to be transmitted. The signal is typically a sinusoidal AC waveform, but may be other wave shapes. The second Frequency2his the second audible frequency signal to be transmitted, after the first. The Signal is typically a sinusoidal AC waveform, but may be other wave shapes. The second frequency2his typically different than first frequency2g.

FIG.3illustrates an exemplary plain-text programming language description for the tone sequence illustrated inFIG.2. A block3aof US-ASCII text characters that together comprise the signal generator's coded definition of a typical two-tone tone-out signal, shown inFIG.2. Plain-text characters define specific characteristics of the signal, and are human-readable. The block3ais broken into smaller blocks with descriptions of each block, in a logical descending order that matches the characters appearance from the left to right. The block3aof the text may include a recipient attribute block or character3b. The illustrated single-character recipient attribute3bmay be used to define specific characteristics about how the signal generator1ashould process a specific recipient7i. For example, the recipient attribute character3bmay be used to determine if the programmed recipient7iappears on the dispatcher screen14or control panel or is invisible.

FIG.4illustrates an exemplary plain-text command language example for tone sequence described inFIG.2andFIG.3. Any example of text4a, which may be displayed on the console terminal15as result of command prompts from signal generator1ato operator, and operator's responses to signal generator1a. The text4aexemplifies typical communications exchange, from the viewpoint of the signal generator1a, between the human operator and the signal generator1aduring the task of programing the signal generator1ato add a new tone-out recipient. The text4aincludes a dollar sign “$”, which is a command language interpreter prompt, appearing on the console terminal15, indicating interpreter is awaiting typed input from the operator. The text4amay also include a single-character command operator4c, illustrated inFIG.4as “M”, which is used to request management of tone-out recipients stored in the non-volatile memory2. Of course the M is exemplary and other commands could be programmed. The text4amay also include a return key4d, which indicates a key on the console terminal or laptop keyboard pressed by operator to transmit a command or operand response to the signal generator.

When the console provides a prompt, it usually is a “:”, or colon4eindicating the operator is expected to type a response. The text4ashows a default value indication4fThe default value indications4fuses square brackets “[ ]” indicate the command language interpreter is providing a suggested default or previously-stored default value. If operator presses the return key4dwithout entering additional data, the default value will be treated as user input for that particular operand or parameter.

FIG.5illustrates an exemplary list of dispatcher screen button/key assignments, which would appear on the signal generator operator interface8, or on the remote dispatcher screen14with programmable pushbutton legends. Each of the pages5a,5b,5c, and5dmay be selected by pressing the buttons for next page or previous page, illustrated as7dfor previous page inFIGS.7and7gfor next page inFIG.7. The select buttons,7b,7cinclude an individual button next to each recipient display line5f. Please note that while the display7hof the signal generator interface8includes four buttons on each side of the display7h, the number of buttons may vary, as well as their placement and configuration, however the signal generator is arranged to minimize potential mistake of toning out the wrong recipient. The blocks of page views,5a,5b,5c, . . .5dare demonstrating a single page of eight recipients associated with eight dispatcher screen or operator panel buttons/keys7b,7con the signal generator interface, whether it is the local signal generator interface8or the remote dispatch screen14. Please note that while the remote dispatch interface14is styled and configured as the signal generator interface8, it could be an electronic version on a touch screen, or a larger version with more selection buttons7b,7cor have a different arrangement, such as a more elongated vertical arrangement as compared to the square shape illustrated in the figures. However for ease of use, it is imagined that may implementations will make the local signal generator interface8and remote dispatch interface or screen14match or be close in configuration to each other to maximize the familiarity between the devices for operators. In the page views illustrated inFIG.5, the recipient numbering is sequential and relative, beginning at 1 and progressing to n recipients, in the illustrated examples, with each screen only containing 8 recipients, however this number is arbitrary and could be any set number of recipients.

Each logical grouping of eight recipients5fis called a page, such as the illustrated pages5a,5b,5c,5d. The recipient selection button/keys on the interfaces,8and14are illustrated as7band7c. Pressing selection button/keys, selected form the group of keys7b,7ccauses the signal generator1ato select or de-select the specified recipient from the queue of recipients7ito later be transmitted when the Dispatcher or operator presses the Send button/key7ffor sending. The selection and queuing of the desired recipients7imay extend across multiple page views. Of course, to avoid selecting each person individually, the signal generator1amay be programmed so that each recipient7iis a group of persons, equipment, stations, or any other grouping. As such Recipient1illustrated inFIG.5may read “Station 1” and selecting it would send a tone to all the persons and equipment relevant and programmed related to Station 1. The queue may automatically clear upon a pressing of the send button7f, or the operator could press the clear button6e. If the queue includes a mistake, it can be cleared and all presently queued recipient de-selected by pressing the Clear button/key7e. It could be programmed so that a short press deselects a selected individual, last individual or allows an operator to press a selection button after pressing the clear button7eto deselect a specific recipient. A long hold on the clear button7ecould clear the whole queue.

As illustrated inFIGS.5and7, the recipient names7imay include human-readable text characters that identify a tone-out recipient in a way that is meaningful to the operator or a Dispatcher. A typical recipient name might be a fire station such as “Station1” or an operation crew group such as “EMS North”, or an individual such as “Jane Smith”. The navigation buttons, as discussed above may include previous page7dand next page7gbuttons. The previous page button button/key7don the interface8,14causes the signal generator1ato move the current page displayed index backwards to a previously displayed page. If at the first page, no action occurs. The next page navigation button/key7gon the interface8,14causes the signal generator to move the current page displayed index forwards to the next page to display. If at the last defined page, no action occurs.

FIG.6illustrates an exemplary step-by step tone-out operation, including selecting multiple recipients7i, now identified as a particular station or equipment. In a multiple recipients queued situation,FIG.6clearly shows how the signal generator will typically send out the tone outs for specific recipients sequentially, however if the signal generator included multiple frequency generators5, it could do multiple tone outs simultaneously. However, given the very short time to execute a tone out, as illustratedFIGS.2and10, there is typically no need to perform the tone outs simultaneously. As suchFIG.6clearly illustrates an exemplary execution flow diagram for typical tone-out operation upon dispatcher/operator request.

FIG.7illustrates an exemplary signal generator with focus on the local signal generator interface8, which may also be similarly provided at the remote dispatch system14. The dispatch screen or operator panel detail diagram7ais printed, painted or otherwise engraved on the outer surface. The operator panel detail is optional, but helpful by putting all the basic operation instructions right in front, as viewed by a human dispatcher or operator. The legend information7atypically describes button/key functions7band7cand provides summarized operating instructions. The select buttons/keys7band7care similar, each associated with, using the optional line7pextending to a recipient7i. In the left column four buttons7bare spatially mapped to the leftmost optical display7hcolumn of recipients7i. Optical display shows the human-readable text characters for a programmed recipient, such as a named fire station or crew group. The right side group of select buttons7care similar with similar functions. One skilled in the art would recognize that the size, shape, number, placement and arrangement of buttons could vary. For example, only 5 could appear on one side with a more elongated display.

As the page navigation buttons PREV7dand NEXT7gare manipulated by the operator, additional programmed recipient names may appear, capable of being selected by the pressing of one of the select buttons7band7c. More specifically, the PREVious page navigation button/key7dallows backwards navigation through programmed recipient pages. Pressing the button7dcauses the signal generator1ato move the currently displayed page index backwards one page. If at the first page of programmed recipients, no further action occurs, but the signal generator1amay be programmed to cycle to the last page. Similarly, the NEXT page navigation button/key7gallows forward navigation through programmed recipient pages. Pressing the NEXT button7gcauses the signal generator to move the currently displayed page index forwards one page. If at the last page of programmed recipients, no further action occurs, but the signal generator may be programmed to also return to the first page of recipients. The last page may be also be reserved as a special system information page which provides information about the current hardware and software version, the current date and time derived from the on-board real time clock. The last page may not have any active recipient information displayed, and could be an instruction manual. In addition, there may be a help or instruction button (not shown) that may allow the signal generator to display a more detailed version of the operating instructions.

The CLEAR button/key7eclears the current to-be-transmitted recipient queue, and navigates to the first page of programmed recipients. If a transmission is currently in progress, pressing this button causes the signal generator to halt transmission at the end of the currently transmitting recipient, clears the to-be-transmitted recipient queue, and navigates to the first page of programmed recipients.

The SEND button/key7fcauses the signal generator to enable Push-To-Talk (PTT) signaling to the attached radio transceivers12, illustrated inFIG.1and begins generating the audible frequency tone signals as defined by the selected recipient configurations. Optional LED or other indicators7kand7lilluminate to indicate which radio transceiver is actively transmitting the signal.

The optical display7hprovides an illuminated view of the human-readable text recipient names and their transmission queue selection status. The display7hmay be vacuum fluorescent, LED, back-lit or reflective LCD, or OLED, or a similar technology providing a daylight-readable, high-contrast rendering of alphanumeric characters and graphical elements.

The recipient name7i, is an exemplary programmed recipient name, in human-readable text. An asterisk “*”, arrow, or similar graphical element is used to indicate the current transmission queue selection status. Pressing a SELection button/key in the left7bor right7ccolumns allows toggling of selection status for a recipient7i. Exemplary recipient7inames may be seen in the other figures.

The system STATUS indicator7jis an optical illuminated indicator that indicates the current operational status of the signal generator. This is optional and may be illustrated in other ways. In the embodiment illustrated in the figures, a status indicator7jwhen illuminated steady indicates normal operations. Non-illuminated means not ready, error, or power off condition. Repeated blinking or sequenced groups of blinks may be used to indicate descriptive fault code status conditions to the dispatcher or operator.

The signal generator1amay also include a PTT1indicator7k. An optical illuminating of the PTT1indicator7kthat indicates that Push-To-Talk signal for attached radio transceiver Radio_1is actively transmitting. Non-illuminated condition indicates PTT is not being asserted. The signal generator1amay include a second PTT indicator7k, or PTT2. Optical illuminating indicator that indicates that Push-To-Talk signal for attached radio transceiver Radio_2is actively transmitting. Non-illuminated condition indicates PTT is not being asserted for the second radio transceiver.

The signal generator1amay include summarized operator instruction text7m, which may be human-readable non-technical instructions to a human dispatcher or operator, describing how to select one or more programmed recipient(s) for transmission. The signal generator's user interface is intentionally designed to be simple to use without extensive training, and no ancillary operator instruction manual is required.

The signal generator1amay include a logo area, such as for a manufacturer logo7n. The signal generator1amay also include model information7o, such as printed brand, model, or product family information.

FIG.8illustrates an exemplary signal generator1afront panel, which may include a power switch1dand an audio outlet, such as the illustrated grille8c. The power switch1dmay be used to control power supply main input. Moving the switch to the “1” position applies power to the signal generator. Moving the switch to the “0” position removes power from the signal generator1a.

FIG.9illustrates an exemplary signal generator1aback/rear panel. The exemplary signal generator1aenclosure back/rear panel may include AC power connector1e, radio port connector(s), console port connector1c, earth grounding screw1t, Ethernet local area network RJ45 connector, and manufacturer serial number and regulatory approval information label. The AC power connector1emay accept industry-standard detachable two-wire with ground power cord. The earth grounding screw1tmay be in any size, shape or configuration, and the illustrated screw has a threaded stud with knurled thumb nut. The earth grounding screw1tmay allow connection of equipment grounding conductor as is typically required by electrical code and industry best practices for safety grounding. The console serial port1callows a connection of a console terminal (FIG.1No.15), laptop or other accessories. Any other type of connection interface may be used, existing or developed in the future.

The radio1port1hallows connection of a radio transceiver (FIG.1No.12). The port1hprovides galvanically isolated Push-To-Talk contact closure, galvanically isolated balanced audio signal, and RS232-level serial transmit and receive data connection to a radio transceiver. Similarly radio2port1sallows connection of a second radio transceiver12and provides the same connections as1h. The ethernet LAN RJ45 port1gallows connection of the signal generator's isolated network interoperability interface11to an external secure network such as an ESInet within a PSAP or dispatch center, or a similar closed-loop secure TCP/IP network within a public safety communications facility. The manufacturer label9hmay include model number, serial number, Ethernet hardware address, regulatory approval information, and manufacturer support contact information.

FIG.10illustrates an exemplary complex recipient type including three sub-elements of an exemplary oscillogram10a. The exemplary oscillogram10afor a complex recipient is assembled from the three different signal type sub-elements10b,10c, and10d. Such complex recipient oscillogram10amight typically be used for large municipalities with advanced tone-out signaling requirements, or for triggering specialized equipment in a fire station or other facility. The sub-element audio signals10b,10c, and10dare generated sequentially by the signal generator and presented without additional silence gaps.

The complex recipient is programmed by first programming the individual sub-elements as if they were standalone recipients. They may be assigned to dispatcher screen buttons/keys which will appear, or may be set to be assigned but not visible or selectable. Once the individual sub-elements have been programmed, the complex recipient can then be programmed, specifying the ID numbers of the individual sub-elements that will together comprise the complete complex recipient. ID numbers consist of the page number and button/key number as organized and depicted in5a. Sub-element1,10bis an exemplary depiction of a typical two-tone signal, similar to that described inFIG.2, sub-element210cis an exemplary depiction of an eight-digit DTMF “Touch-Tone” sequence, and sub-element3,10d. Example depicts a single tone burst repeated three times. Typical of a human-audible signal to alert personnel.

FIG.11illustrates an exemplary plain-text programming language example for complex recipient tone sequence inFIG.10. Block of US-ASCII text characters11athat together comprise the current invention's coded definition of a typical complex recipient signal as shown inFIG.10. Plain-text characters define specific characteristics of the complex recipient, and are human-readable. Individual sub-elements11bare specified with a two-character ID, the first character being the page number, and the second character being the recipient button/key assignment for that page, as set forth in5a.

The tone generator system1zincludes a tone generator or signal generator1a, a power source such as AC mains1eor a battery1f, at least one radio transceiver1p, and radio connection cable1o. The at least one radio transceiver1pmust be connected to an antenna1q. To program tone-out recipients in the signal generator1a, a console terminal device such as a laptop15may be connected to the signal generator with a serial cable1k. Optionally, the signal generator1amay be connected to an external clock source such as a GPS satellite clock16through serial connection cable1jto signal generator1aauxiliary serial port1b. Optionally the signal generator1amay also be connected to a secure Ethernet network1nvia an industry-standard Ethernet cable1l. The signal generator1agenerally includes a microprocessor module1in communication with a real time clock module3and a non-volatile memory module2, configured to store the programmed tone-out recipients. The tone or signal generator1afurther includes an internal bus1iin communication with the microprocessor module1and a multi-channel synthesis core/frequency generator module5, and a radio interface control logic module6, and a user interface control logic module7configured to interface with a display module7hon the illustrated local user interface8.

The signal generator1aprovides unique advantages over the prior art, on such advantage is the ability to generate dual tones, such as dtmf tones. None of the prior art tone generators can generate dual tones, only sequential tones. The signal generator1aof the present invention generates hundreds of tones without any add ons or hardware changes, and can easily be programed for different tones by the user. The present invention may also have a network interface1land1gto allow the signal generator1ato communicate with the external internet.

The microprocessor module1may tell the amplifier9how much amplification and can also specify wave shape in the multi-channel synthesis core frequency generator5, in addition to dividing down to the desired frequency. The desired frequency is based on the signal from the master reference oscillator4, which is divided to make the desired frequency and provides the precision and accuracy of the present invention. While no local user interface is required and the signal generator1amay be controlled remotely, a local user interface8is helpful if there is communication issues with the remote user interfaces. As such a local user interface with selection, tone out or send buttons and a display is helpful as a backup or even primary interface.

Another unique aspect of the signal generator is its ability to directly communicate with the radios through the radio ports1hand1s. As such, the signal generator1amay determine what model, brand, channel radios and also can change radio channels, which allows it to virtually cover every commonly used radio channel, without hardware changes. As illustrated, the signal generator1amay be connected to the uhf and vhf radio transceivers1pand cover almost all channels. This allows a simple selection of a recipient and pushing the send button by the operator and the signal generator may change channels and send the proper tone out signals. More specifically, one device can do what in the past could require dozens of devices for large municipalities. For example, county that provides central dispatching for their local municipalities has almost forty different radios signal generators connected and the small portable signal generator1aof the present invention could replace all of the m with a single device, and is simple to program by a non-technical user, as compared to the county system referenced above which needed specialized technical programing with over a million dollars spent on installation cost. As more municipalities combine dispatching and other functions, the signal generator provides a simple, easy to use and cost efficient device that replaces multiple other devices. As stated above, each municipality uses different frequencies to avoid interference, and as such this expense to generate multiple frequencies has prevented many dispatch centers from combining due to cost concerns. The existing systems are also very internet and personal computer dependent and a flaw or bug in one can prevent paging out of the proper first responders and has in the past required police officers to be dispatched by radio to notify fire department personnel that their services are needed.

Another advantage of the present invention is the complex tones it can create with a single portable device. More specifically, the signal generator1amay control multiple aspects of the tone individually, and prior art systems do not offer such flexibility. The present invention can even create non-linear wave forms.