Communication device and method for determining a busy status thereof in a dispatch system

A communication device (e.g., 103) includes a user interface (209), a receiver (203), a controller (205), and a transmitter (201). A user of the communication device uses the user interface to place the communication device in a busy operational mode in which the communication device is not involved in a voice communication, but is nevertheless unavailable to participate in a voice communication. While in the busy mode, the communication device receives a voice communication from a calling device (e.g., 104) and automatically responds with a data message indicating that the communication device is in the busy mode, thereby informing a user of the calling device of the busy status of the called device without disrupting the user of the called device.

FIELD OF THE INVENTION
 The present invention relates generally to communication devices and, in
 particular, to determining an operational status of a communication
 device.
 BACKGROUND OF THE INVENTION
 Radio communication systems are known to include a radio communication
 infrastructure and mobile or portable communication devices. Some systems
 (e.g., cellular systems) primarily support telephone communications, while
 other systems (e.g., trunked or conventional systems) primarily support
 dispatch communications. Some systems, such as Motorola's "iDEN" system,
 provide multiple services, such as telephone, dispatch, data, and short
 message, all in a single communications platform.
 Regardless of the type of system, radio users in the system occasionally
 need to attend meetings or be in other situations in which they do not
 wish to be disturbed or interrupted. Cellular systems and normal wireline
 telephone systems accommodate such desires by providing voice mail service
 to their users. However, such is currently not the case in dispatch
 systems. In a dispatch system, when a user wants to be uninterrupted, the
 user must turn off his or her radio, or mute the audio. Although such
 action by the user allows him or her to remain undisturbed, the action
 does nothing to inform the callers that he or she is active in the system,
 but cannot respond at the moment.
 In a dispatch system, when a user turns off his or her radio and another
 user attempts to contact him or her, the calling user receives a message
 from the radio communication infrastructure, such as "TARGET NOT
 AVAILABLE." Such a message is indeterminate because it could mean that the
 called device is powered off or it could mean that the called device is
 powered on, but simply out of the system coverage area. Accordingly, since
 the user of the calling device does not know the exact status of the
 called device, the user of the calling device continues to attempt to
 contact the user of the called device. Such retries are an inefficient use
 of system resources when the called user's intent was to remain
 undisturbed anyway.
 Therefore, a need exists for a communication device and method for
 determining an operational status thereof that permits the communication
 device to remain active in the system at all times and that provides
 determinate feedback to calling device users that are attempting to
 contact the communication device at times when a user of the communication
 device does not wish to be disturbed.

DESCRIPTION OF A PREFERRED EMBODIMENT
 Generally, the present invention encompasses a communication device and
 method for determining an operational status thereof. The communication
 device includes a user interface, a receiver, a controller, and a
 transmitter. A user of the communication device uses the user interface to
 place the device in a busy operational mode in which the device is not
 involved in a voice communication, but is nevertheless unavailable to
 participate in a voice communication. While in the busy mode, the
 communication device receives a voice communication from a calling device
 and automatically responds with a data message indicating that the
 communication device is in the busy mode, thereby informing the user of
 the calling device of the busy status of the communication device. By
 providing a busy status indication to a calling device in this manner, the
 present invention enables a person calling the busy device to determine
 that the user of the busy device is active in the communication system,
 but is presently unavailable to communicate, without interrupting the user
 of the called device or the user's company at the time of the call.
 Knowing that the user of the busy mode device is unavailable because the
 user of the busy mode device intentionally placed the device in the busy
 mode, the user of the calling device can determine appropriate future
 action (e.g., contacting someone else) without having to repeatedly
 attempt to contact the user of the busy mode device.
 The present invention can be more fully understood with reference to FIGS.
 1-5. FIG. 1 illustrates a block diagram depiction of a radio communication
 system 100 in accordance with a preferred embodiment of the present
 invention. The preferred radio communication system 100 includes a radio
 communication system infrastructure 101, at least two radio communication
 devices 103, 104 (two shown), at least one wireline communication device
 105 (one shown), the public switched telephone network (PSTN) 109, and a
 voice mail server 111. The radio communication system infrastructure 101
 preferably comprises "iDEN" communication system infrastructure equipment
 that is commercially available from Motorola, Inc. of Schaumburg, Ill. In
 an alternative embodiment, the radio communication system 100 might
 comprise any cellular or trunked communication system, such as
 communication systems that implement one or more of the following cellular
 platforms: Personal Communication Service (PCS), Advanced Mobile Phone
 Service (AMPS), Narrowband AMPS (NAMPS), Unites States Digital Cellular
 (USDC), Code Division Multiple Access (CDMA), or Global System for Mobile
 Communications (GSM). As depicted in FIG. 1, the radio communication
 system infrastructure 101 preferably includes a short message service
 (SMS) processor 107, such as the Telepath Short Message Service Center
 (SMSC) that is commercially available from Aldiscon, Inc. of Dallas, Tex.
 The radio communication devices 103, 104 preferably comprise "iDEN"
 radiotelephones and preferably include a transmitter 201, a receiver 203,
 a controller 205, a memory device 207, a user interface 209, and a timer
 211 as illustrated in block diagram form in FIG. 2. The transmitter 201
 preferably comprises a linear transmitter capable of transmitting
 quadrature amplitude modulated (QAM) signals. The receiver 203 preferably
 comprises a digital receiver capable of receiving QAM signals. The
 controller 205 preferably comprises a microprocessor and its associated
 logic circuitry. The memory device 207 preferably comprises a random
 access memory (RAM) and the timer 211 preferably comprises a known digital
 timer. Although shown as separate elements in FIG. 2, the memory device
 207 and the timer 211 preferably form respective portions of the
 controller 205. The user interface 209 preferably comprises a display, a
 keypad, menu buttons, function buttons, and/or a touch screen.
 The voice mail server 111 comprises a well-known telephone voice mail
 system and the wireline communication device 105 comprises a telephone, a
 personal computer, a palm top computer, or a personal digital assistant
 (PDA). The PSTN 109 is well known;
 thus, no further discussion will be presented except as may be necessary to
 more fully describe the present invention.
 With reference to FIGS. 1 and 2, operation of the preferred radio
 communication system 100 occurs substantially as follows in accordance
 with the present invention. When a user of a radio communication device
 (e.g., 103) decides that he or she cannot be disturbed for a certain
 duration of time, but that he or she wants to remain registered in the
 communication system, the user uses the user interface 209 (e.g., by
 scrolling down a mode menu and depressing a selection button to activate
 the selected mode) to place the communication device 103 in a busy
 operational mode. In the busy operational mode, the communication device
 103 remains registered in the system, but does not disturb the user of the
 device 103 upon receipt of a communication.
 After the communication device 103 has entered the busy mode, another
 communication device (e.g., radio communication device 104 or wireline
 communication device 105) may desire to contact the user of the busy mode
 communication device 103. In such a case, the calling communication device
 (e.g., radio communication device 104) transmits a voice communication to
 the busy mode device 103 via one or more radio communication resources
 113, 115 and, if necessary, the radio communication system infrastructure
 101 in accordance with known techniques. As contemplated by the present
 invention, each radio communication resource 113, 115 might comprise a
 radio frequency (RF) channel in a frequency division multiple access
 (FDMA) system, such as AMPS, one or more time slots on an RF channel in a
 time division multiple access (TDMA) system, such as the "iDEN" system, or
 an orthogonal code, such as a pseudo-noise sequence or a frequency-hopping
 pattern, in a CDMA system.
 For example, when the calling communication device 104 and the busy mode
 device 103 are in a so-called talk-around mode in which the two devices
 103, 104 communicate directly without interaction of the radio
 communication system infrastructure 101, the calling device 104 transmits
 the voice communication directly to the busy mode device 103 via a single
 communication resource without involvement of the radio communication
 system infrastructure 101. However, when the calling radio communication
 device 104 and the busy mode device 103 are not in the talk-around mode or
 when the calling communication device is a wireline communication device
 105, the calling device transmits the voice communication to the busy mode
 device 103 via the radio communication system infrastructure 101 (and the
 PSTN 109 when the voice communication originates from a wireline
 communication device 105).
 Once the voice communication is transmitted to the busy mode device 103,
 the busy mode device 103 employs its receiver 203 to receive the voice
 communication and alert the controller 205 that a voice communication has
 been received for the user of the busy mode device 103. Upon receipt of
 the alert, the controller 205 determines whether the communication device
 103 is in the busy operational mode and whether the calling device 104 is
 data capable. The controller 205 determines that the communication device
 103 is in the busy operational mode by monitoring the user interface 209
 and detecting when the appropriate key, button, or sequence of keys and/or
 buttons are depressed or selected by the user of the communication device
 103 to place the communication device 103 in the busy operational mode.
 When the controller 205 detects that such key, button, or sequence of keys
 and/or buttons were depressed or selected by the user, the controller 205
 stores a busy mode status indication in its memory (e.g., memory device
 207).
 In the preferred embodiment, the sequence of key or button selections used
 by the user of the communication device 103 to place the communication
 device 103 in the busy operational mode includes a selection of the time
 period during which the communication device is to remain in the busy
 operational mode. Upon receipt of the time period selection, the
 controller 205 starts the timer 211. The timer 211 expires after the
 selected time period and the controller 205 returns the communication
 device 103 (e.g., by removing the busy status indication stored in memory)
 to its normal, non-busy operational mode in which the communication device
 103 is available to participate in voice communications. In an alternative
 embodiment, the user of the communication device 103 might not indicate
 the time duration for busy mode operation. In this case, the communication
 device 103 remains in the busy operational mode until the user of the
 communication device 103 cancels such mode by selecting or depressing the
 appropriate key, button, or sequence of keys and/or buttons.
 The controller 205 determines that the calling device 104 is data capable
 by determining whether the communication device 103 itself is data
 capable. That is, when the communication device 103 is data capable, the
 communication device 103 presumes that the calling device 104 is also data
 capable if the calling device 104 is supported by the radio communication
 system infrastructure 101. Similarly, when the communication device 103 is
 not data capable, the communication device 103 presumes that the calling
 device 104 is not data capable if the calling device 104 is supported by
 the radio communication system infrastructure 101. In accordance with the
 present invention, a communication device 103, 104 is data capable when it
 is capable of receiving short data messages, such as SMS messages, even
 though it may not also be capable of receiving packet data or circuit data
 transmissions. The controller 205 is programmed with the communication
 device's capabilities at a time when the communication device 103 is
 provisioned by the radio system operator.
 When the calling device 104 is data capable and the communication device
 103 is in the busy operational mode, the controller 205 generates a data
 message for transmission to the calling device 104 to inform the calling
 device 104 that the communication device 103 is in the busy operational
 mode. In the preferred embodiment, the controller 205 selects one of a
 plurality of user-defined messages stored in the memory device 207 as the
 data message for conveyance to the calling device 104. For example, prior
 to placing the communication device 103 in the busy operational mode, the
 user of the communication device 103 might create his or her own messages
 for transmission to calling communication devices when the communication
 device 103 is in the busy mode. Alternatively, the communication device
 103 may include one or more preset or "canned" messages that the user can
 select from prior to placing the communication device 103 in the busy
 mode. In a further embodiment, the SMS processor 107 of the radio
 communication system infrastructure 101 might include a memory containing
 canned busy mode messages that are transmitted to the calling device 104
 upon the radio communication system infrastructure 101 being informed by
 the communication device 103 that the device 103 is in the busy mode.
 In addition to generating a data message, the busy mode device 103
 preferably stores an identification (ID) of the calling device 104 in a
 memory (e.g., memory device 207) of the busy mode device 103. Upon receipt
 of the communication, the receiver 203 of the called device 103 extracts
 the ID of the calling device 104 from the communication in accordance with
 known techniques and the controller 205, upon detecting that the called
 device 103 is in the busy operational mode, instructs the receiver 203 to
 store the ID of the calling device 104 in the memory device 207. The user
 of the called device 103 can then retrieve the IDs of the communication
 devices 104, 105 that called the called device 103 when the called device
 103 was in the busy operational mode at a later time when the called
 device 103 is no longer in the busy mode. In the preferred embodiment,
 only unique calling device IDs are stored in the memory device 207 to
 minimize memory size. Thus, before instructing the receiver 203 to store
 the calling device ID in memory, the controller 205 first scans the memory
 to determine whether the ID of the calling device 104 is already stored.
 When the ID of the calling device 104 is already stored, no additional
 storage is necessary. In addition to storing the calling device IDs, the
 called device 103 might also store the time each call was received (e.g.,
 when the called device 103 has the capability to determine such time
 (e.g., when the called device 103 includes a global positioning satellite
 (GPS) receiver )) or the time each call was transmitted from the radio
 communication system infrastructure 101 (e.g., when the radio
 communication system infrastructure 101 timestamps each transmission).
 Having determined that the called communication device 103 is in the busy
 mode, determined that the calling communication device 104 is data
 capable, and generated the data message, the controller 205 provides the
 data message to the transmitter 201 for transmission to the calling device
 104. The transmitter 201 transmits the data message to the calling device
 104 either directly or via the radio communication system infrastructure
 101. In the preferred embodiment, the radio communication system
 infrastructure 101 includes an SMS processor 107 and the busy mode device
 103 conveys the data message as a short message to the calling device 104
 via the SMS processor 107 in accordance with known techniques. Once the
 calling device 104 receives the data message, the calling device 104
 preferably displays the data message as a text message to a user of the
 calling device 104 to inform the user that the called device 103 is
 currently in the busy operational mode.
 When the controller 205 determines that the calling communication device
 104 is not data capable, the controller 205 further determines whether the
 communication is a dispatch call or a telephone call. When the
 communication is a telephone call, the controller 205 determines whether
 the busy mode device 103 has voice mail service. Such a determination may
 be made by querying the radio communication system infrastructure 101 or
 by examining the service identifications that were stored in the busy mode
 device 103 at the time the busy mode device 103 was provisioned in the
 radio communication system 100. When the busy mode device 103 has voice
 mail service, the busy mode device 103 automatically forwards the
 communication to the voice mail server 111 supporting the voice mail
 service for the busy mode device 103. When the communication is a dispatch
 call, the busy mode device 103 appears busy to the calling device 104 and
 the calling device 104 audibly alerts its user (e.g., using a series of
 beeps) that the called device 103 is in a busy mode.
 Although the present invention was discussed above primarily with respect
 to its use in radio communication devices, the present invention is also
 applicable for use in and with wireline communication devices. However,
 the present invention is most practically utilized in dispatch radio
 communication systems, wherein a group of users may be attempting to
 contact one member of the group on a regular basis. With the present
 invention, the group may be informed collectively that the called device
 103 is in the busy mode (e.g., via one transmission of the data message to
 all group members on a shared radio communication resource) or each member
 of the group may be so informed individually (e.g., by multiple
 transmissions of the data message in response to private calls).
 As described above, the present invention provides a communication system
 in which communication device users can place their communication devices
 in a busy mode when they do not wish to be disturbed, but do desire to
 remain active in the system. In accordance with the present invention, a
 busy mode device informs any calling device of its busy status, preferably
 through an SMS message, without disturbing a user of the calling device
 either audibly or via a vibration. By storing each unique calling device
 ID, the present invention allows the busy mode device user to determine
 who tried to contact him or her. In addition, by all users in the system
 having knowledge of the busy mode feature, the present invention allows
 calling device users to know that, upon receiving a busy mode data message
 from a called device, the user of the called device has been informed of
 the attempted contact and will respond as soon as he or she is able to do
 so. Thus, in contrast to prior art approaches of turning off a
 communication device or muting audio (neither of which both satisfies the
 called device user's desire to remain in the system and informs the
 calling device user of the status of the called device), the present
 invention permits a user to leave his or her radio on in situations in
 which he or she does not wish to be disturbed, while knowing that
 attempted contacts will be logged and that calling device users are being
 informed of the user's current inability to communicate with them.
 FIG. 3 illustrates a logic flow diagram 300 of steps executed by a called
 communication device to inform a calling communication device of an
 operational status of the called communication device in accordance with a
 preferred embodiment of the present invention. The logic flow begins (301)
 when the called device enters (303) a busy operational mode. As discussed
 above, the busy operational mode is an operational mode in which the
 called device is not involved in a voice communication, but is
 nevertheless unavailable to participate in a voice communication. For
 example, a user of the called device might configure the called device in
 the busy operational mode when the user of the called device is attending
 a meeting and cannot respond to a voice communication intended for the
 user.
 Sometime after entering the busy operational mode, the called device
 receives (305) a voice communication from the calling device. The called
 device stores (307) the identification (ID) of the calling device for
 future use by the user of the called device. By storing the ID of the
 calling device, the called device permits the user to retrieve the ID of
 the calling device at a later time when it is more convenient for the user
 of the called device to contact the user of the calling device.
 Once the voice communication has been received by the called device, the
 called device determines (309) whether the calling device is data capable.
 The called device preferably determines whether the calling device is data
 capable by determining whether the called device itself is data capable
 and presuming that when the called device is data capable, the calling
 device is also data capable if the calling device is supported by the same
 radio communication system infrastructure as is the called device.
 When the called device determines that the calling device is data capable,
 the called device automatically transmits (311) a data message to the
 calling device indicating that the called communication device is in the
 busy operational mode. In the preferred embodiment, the data message is
 one of a plurality of user defined text messages prestored in the memory
 of the called device.
 For example, the prestored message might simply say "Busy Right Now."
 Therefore, when the called device is in the busy mode and receives a voice
 communication, the called device responds with the pre-defined data
 message to the calling device informing the calling device that the called
 device is operational in the system, but that the user of the called
 device is busy at the moment and cannot receive the voice communication.
 The data message may be transmitted to the calling communication device
 either directly (e.g., when the two communication devices are in so-called
 talkaround mode) or via an infrastructure of a radio communication system
 (e.g., when the two communication devices are not in talkaround mode or
 are actively operating in a communication system supported by radio
 infrastructure equipment). Once the data message has been transmitted, the
 logic flow ends (313).
 When the calling device is not data capable (309), and the voice
 communication is a telephone call, the called device forwards (315) the
 voice communication to a voice mail server for the called device if the
 called device has voice mail service. Forwarding of the voice
 communication may occur dynamically or may be predetermined. When dynamic
 forwarding is employed, the user of the called device is alerted (e.g., by
 a vibration device in the called device) that a voice communication has
 been received and, if the called device has a display, may be informed by
 the display as to the identity of the user of the calling device.
 Responsive to the alert, the user of the called device selects (e.g., by
 depressing a function key on a keypad of the called device) the
 destination device for forwarding, such as a secretary's telephone, a home
 answering machine, or a phone of another appropriate individual. When
 static or predetermined forwarding is employed, the user of the called
 device presets the forwarding destination in the radio communication
 system by sending a control message to the radio system infrastructure
 indicating that all telephone calls intended for the called device are to
 be forwarded to a particular destination device, such as an answering
 machine or a telephone of an appropriate individual.
 When the calling device is not data capable and has not subscribed to voice
 mail service, the called device might indicate that it is in a busy
 operational mode by sending a preset tone pattern to the calling device
 which can then be audibly replayed to the user of the calling device to
 inform the user of the calling device that the called device is in the
 busy operational mode. Once the telephone call has been forwarded to voice
 mail or an appropriate individual, or the calling device has, in some
 other manner, been informed that the called device is in the busy
 operational mode, the logic flow ends (313).
 FIG. 4 illustrates a logic flow diagram 400 of steps executed by a calling
 communication device to determine an operational status of a called
 communication device in accordance with a preferred embodiment of the
 present invention. The logic flow begins (401) when the calling device
 transmits (403) a voice communication to the called or target device.
 Sometime later, responsive to the voice communication transmission, the
 calling device receives (405), either directly from the target device
 (e.g., when the two communication devices are in so-called talkaround
 mode) or via an infrastructure of a radio communication system (e.g., when
 the two communication devices are not in talkaround mode or are actively
 operating in a communication system supported by radio infrastructure
 equipment), a data message indicating that the target device is in a busy
 operational mode in which the target device is not involved in a voice
 communication, but is nevertheless currently unavailable to participate in
 a voice communication. As mentioned above, a user of the target device may
 put the target device in the busy operational mode when he or she wants
 the target device to remain active in the communication system, but does
 not want to be disturbed by voice activity for a certain duration of time
 (e.g., while the user of the target device is attending a meeting).
 Upon receiving the data message, the calling device displays (407) the data
 message as a text message to a user of the calling communication device
 and the logic flow ends (409). In an alternative embodiment, when the
 calling device does not have a text display, the calling device may inform
 its user that the target device is in the busy operational mode by
 providing a predetermined audio signal (e.g., a series of tones or beeps)
 to the user of the calling device via the calling device's speaker. In yet
 another embodiment, when the calling device does not include a text
 message display, the calling device may inform its user that the target
 device is in the busy operational mode by converting the data message to a
 voice message and audibly providing the voice message (e.g., "I am busy
 now") to the user of the calling device via the calling device's speaker.
 FIG. 5 illustrates a logic flow diagram 500 of steps executed by an
 infrastructure of a radio communication system to inform a calling
 communication device of an operational status of a called communication
 device in accordance with the present invention. The logic flow begins
 (501) when the infrastructure receives (503) a voice communication from
 the calling device. The infrastructure transmits (505) the voice
 communication to the called device. When the called device is in the busy
 operational mode, the infrastructure receives (507) a data message from
 the called device indicating that the called device is in the busy
 operational mode. The infrastructure then transmits (509) an
 acknowledgment of receipt of the data message to the called device.
 When the infrastructure includes a short message service (SMS) processor,
 the SMS processor determines (511) a short text message based on the data
 message received from the called device. The short text message may simply
 be the data message itself or may be generated from a database or lookup
 table in the SMS processor based on the data message. For example, the
 data message might comprise all ones and the database in the SMS processor
 might indicate that all ones translates into a text message, such as "BUSY
 NOW" or "DO NOT DISTURB." Once the short text message is determined, the
 infrastructure transmits (513) the short text message to the calling
 device in accordance with known techniques and the logic flow ends (515).
 In an alternative embodiment, when the infrastructure does not include an
 SMS processor, the infrastructure simply transmits the data message to the
 calling device.
 The present invention encompasses a communication device and method for
 determining an operational status thereof. With such an invention, radio
 users can leave their radios on when attending important meetings in which
 they do not wish to be disturbed by voice, audible beeps, or a vibration.
 In addition, the present invention provides express feedback to calling
 device users that are attempting to contact the radio users in the
 meetings. In contrast to indeterminate messages, such as "TARGET NOT
 AVAILABLE," received by existing calling devices when a radio user is out
 of the system coverage area or has his or her radio turned off, the
 present invention provides a determinate message that allows a calling
 device user to know that the called device is active in the system, has
 been contacted, and that the user of the called device is busy, but will
 return their call at a later time. Accordingly, the present invention
 permits more efficient use of the system (less call retries by uninformed
 callers) and allows called users to determine, by stored ID or voice mail,
 who attempted to contact them while they were busy.
 While the present invention has been particularly shown and described with
 reference to particular embodiments thereof, it will be understood by
 those skilled in the art that various changes in form and details may be
 made therein without departing from the spirit and scope of the present
 invention.