Abstract:
A method of operating a wireless calling device comprises connecting to a call tone provider configured to provide call tones, transferring a plurality of call tone requests to the call tone provider, receiving a plurality of call tones from the call tone provider in response to the plurality of call tone requests, transferring a call setup message to a telecommunication switch to initiate a call, receiving a call message from the telecommunication switch in response to the call setup message wherein the call setup message indicates a status of the call, processing the call message to select a one call tone from the plurality of call tones based on the status of the call, and audibly playing the one call tone.

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 11/343,722, that was filed on Jan. 31, 2006; that is titled “CALL PROGRESS TONE GENERATION IN A COMMUNICATION SYSTEM;” and that is hereby incorporated by reference into this patent application; and which is a continuation of U.S. patent application Ser. No. 10/103,576 filed Mar. 21, 2002; that is titled “CALL PROGRESS TONE GENERATION IN A COMMUNICATION SYSTEM”; and that is hereby incorporated by reference into this patent application. 
     FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     MICROFICHE APPENDIX 
     Not applicable. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to the field of communication systems, and more particularly, to calling devices that generate and play call progress tones. 
     2. Description of the Prior Art 
     When making a call, a caller may hear tones or message being played that indicate the status of a call. The tones are commonly referred to as call progress tones (CPT), which are audible tones or messages played to indicate the progress of a call. One example of a call progress tone is a slow busy signal that indicates that the called party is not available. Another example of a call progress tone is a fast busy signal that indicates that the system is busy. Another example of a call progress tone is a message stating that the line is busy. 
     A typical communication system is comprised of a calling device coupled to an originating system. The originating system is coupled to a Public Switched Telephone Network (PSTN). Examples of calling devices are telephones, cellular phones, computers, and fax machines. An example of the originating system is a class-5 switch. 
     A user of the calling device initiates a call to a called device in the PSTN through the originating system. The calling device transmits set up messages to the originating system. The originating system sets up the call by exchanging signaling with a terminating system connected to the called device. The terminating system transmits acknowledgment messages to the originating system to indicate the progress of the call. The acknowledgment messages inform the originating system whether the call can be completed. For instance, the acknowledgment messages indicate that the PSTN is busy, that the called device is busy, that the called device is being alerted, or some other event. The originating system processes the acknowledgment messages to determine the proper call progress tone for the call. The originating system generates and transmits the call progress tone to the calling device. The calling device plays audible sounds that represent the call progress tone so that the user of the calling device can hear it. 
     Unfortunately, the originating system generates the call progress tones and maintains the call to transmit the call progress tones, which increases the workload on the originating system. Consequently, the originating system does not effectively handle other calls, which could adversely affect the performance of the communication system. 
     This can be a particular problem in wireless networks. The originating system transmits the call progress tones over a frequency to a wireless phone. Frequencies and bandwidth are valuable commodities in a wireless network, and the originating system uses valuable bandwidth to transmit the call progress tones. 
     SUMMARY OF THE INVENTION 
     In an embodiment of the invention, a method of operating a wireless calling device comprises connecting to a call tone provider configured to provide call tones, transferring a plurality of call tone requests to the call tone provider, receiving a plurality of call tones from the call tone provider in response to the plurality of call tone requests, transferring a call setup message to a telecommunication switch to initiate a call, receiving a call message from the telecommunication switch in response to the call setup message wherein the call setup message indicates a status of the call, processing the call message to select a one call tone from the plurality of call tones based on the status of the call, and audibly playing the one call tone. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The appended claims set forth the features of the present invention with particularity. The invention, together with its advantages, may be best understood from the following detailed description taken in conjunction with the accompanying drawings: 
         FIG. 1  is a block diagram that depicts a communication system in the prior art; 
         FIG. 2  is a signal diagram for the communication system in  FIG. 1  in the prior art; 
         FIG. 3  is a block diagram that depicts a communication system in an example of the invention; 
         FIG. 4  is a signal diagram for the communication system in  FIG. 3  in an example of the invention; 
         FIG. 5  is a block diagram that depicts a communication system wherein a calling device has a wireline connection with a switch in an example of the invention; 
         FIG. 6  is a block diagram that depicts a communication system wherein a calling device has with a wireless connection with a switch in an example of the invention; 
         FIG. 7  is a signal diagram for the communication systems in  FIGS. 5 and 6  in an example of the invention; 
         FIG. 8  is a flow diagram of a process executed by a switch to provide call progress tones in an example of the invention; 
         FIG. 9  is a flow diagram of a process executed by a calling device to provide call progress tones in an example of the invention; 
         FIG. 10  is a block diagram that depicts a switch in an example of the invention; 
         FIG. 11  is a block diagram that depicts a calling device in an example of the invention; 
         FIG. 12  is a flow diagram of a process executed by a calling device to update a call progress tone table in an example of the invention; and 
         FIG. 13  is a flow diagram of a process executed by a switch to update a calling device database in an example of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Prior Art Communication System—FIGS.  1 - 2   
       FIG. 1  illustrates communication system  100  in the prior art. Communication system  100  comprises a calling device  102 , an originating system  104 , and a terminating system  106 . Calling device  102  is any device configured to play audible sounds that represent call progress tones (CPT). Originating system  104  is any system configured to set up and maintain a call. 
       FIG. 2  illustrates a signal diagram for communication system  100 . Calling device  102  initiates a call to terminating system  106  through originating system  104 . Calling device  102  transmits a first set up message to originating system  104 . Originating system  104  processes the first set up message and generates a second set up message. Originating system  104  transmits the second set up message to terminating system  106 . Originating system  104  receives an acknowledgment (ACK) message from terminating system  106 . The acknowledgment message indicates the progress of the call. Originating system  104  processes the acknowledgment message to determine a call progress tone. Call progress tones are tones or messages that indicate the progress of the call. Originating system  104  generates the call progress tone and transmits the call progress tone to calling device  102 . Calling device  102  plays audible sounds that represent the call progress tone. The user of calling device  102  can determine the progress of the call by listening to the call progress tone played by calling device  102 . Originating system  104  releases the call if calling device  102  hangs up. 
     First Embodiment of a Communication System—FIGS.  3 - 4   
       FIGS. 3-4  depict a specific example of a communication system in accord with the present invention. Those skilled in the art will appreciate numerous variations from this example that do not depart from the scope of the invention. Those skilled in the art will also appreciate that various features described below could be combined with other embodiments to form multiple variations of the invention. Those skilled in the art will appreciate that some conventional aspects of  FIGS. 3-4  have been simplified or omitted for clarity. 
       FIG. 3  depicts communication system  300  in an example of the invention. Communication system  300  is comprised of calling device  302 , originating system  304 , and terminating system  306 . Calling device  302  is configured to communicate with originating system  304 . Originating system  304  is configured to communicate with terminating system  306 . 
     A call typically includes signaling and user communications. Calling device  102  is any device capable playing audible sounds that represent call progress tones (CPT). Call progress tones are tones or messages that indicate the progress of a call. Originating system  304  is any system capable of setting up and maintaining a call. Terminating system  306  is any system capable of communicating with originating system  304  for a call. 
       FIG. 4  illustrates a signal diagram for communication system  300  in an example of the invention. Calling device  302  initiates a call with terminating system  306  through originating system  304 . Calling device  302  transmits a first set up message to originating system  304 . Originating system  304  processes the first set up message and generates a second set up message. Those skilled in the art will appreciate that some conventional steps for setting up and placing a call will not be discussed for the sake of brevity. Originating system  304  transmits the second set up message to terminating system  306 . 
     Originating system  304  then receives an acknowledgment (ACK) message from terminating system  306 . Originating system  304  processes the acknowledgment message to generate a call progress message. A call progress message is any tone, signal, message that indicates the status of a call. Originating system  304  transmits the call progress message to calling device  302 . 
     Calling device  302  receives the call progress message. Calling device  302  processes the call progress message to determine a call progress tone. Calling device  302  generates the call progress tone and plays audible sounds that represent the call progress tone. 
     In this example, calling device  302  advantageously generates the call progress tone instead of originating system  304 . Originating system  304  is then able to release the call after transmitting the call progress message to calling system  302 . Originating system  304  can then handle other calls. 
     Second Embodiment of a Communication System—FIGS.  5 - 13   
       FIGS. 5-13  depict specific examples of a communication system in accord with the present invention. Those skilled in the art will appreciate numerous variations from these examples that do not depart from the scope of the invention. Those skilled in the art will also appreciate that various features described below could be combined with other embodiments to form multiple variations of the invention. Those skilled in the art will appreciate that some conventional aspects of  FIGS. 5-13  have been simplified or omitted for clarity. 
       FIG. 5  depicts an example of communication system  500 . Communication system  500  is comprised of calling device  502 , switch  504 , switch  506 , called device  508 , and Public Switched Telephone Network (PSTN)  510 . Switch  504  includes database  512 . 
     Calling device  502  is configured to communicate with switch  504 . In this example, calling device  502  communicates with switch  504  over a wireline link. Switch  504  is configured to communicate with PSTN  510 . Those skilled in the art will appreciate that switch  504  communicates with PSTN  510  over a signaling link and a bearer link. PSTN  510  is configured to communicate with switch  506 . Those skilled in the art will appreciate that switch  506  communicates with PSTN  510  over a signaling link and a bearer link. Switch  506  is configured to communicate with called device  508 . Examples of calling device  502  include, but are not limited to, telephones, computers, and fax machines. Switches  504 ,  506  comprise conventional switches such as class-5 switches produced by Lucent Technologies. 
       FIG. 6  depicts another example of communication system  500 . In this example, calling device  502  communicates with switch  504  over a wireless link. The wireless link is facilitated by a tower  612  coupled to a base station  614 . In this example, calling device  502  could be a cellular phone. 
     To illustrate communication between calling device  502  and switch  504 , tower  612  receives wireless signals from calling device  502 . The wireless signals include signaling and user communications. Tower  612  and base station  614  function together to convert the wireless signals into wireline signals. Base station  614  transfers the wireline signals to switch  504 . Tower  612  and base station  614  function in a similar manner to receive wireline signals from switch  504 , convert the wireline signals to wireless signals, and transfer the wireless signals to calling device  502 . 
       FIG. 7  illustrates a signal diagram of communication system  500  in an example of the invention. Calling device  502  initiates a call with called device  508  through switches  504 ,  506  and PSTN  510 . To initiate the call, calling device  502  transmits Dual Tone Multi Frequency (DTMF) signaling to switch  504 . Examples of signaling include Signaling System 7 (SS7) and C7. One skilled in the art will recognize that the following steps may involve more signaling depending on the protocol used in communication system  500 . Switch  504  processes the DTMF signaling and generates an Initial Address Message (IAM). Switch  504  transmits the IAM to switch  506  over PSTN  510 . Switch  506  processes the IAM and generates an Address Complete Message (ACM). Switch  506  transmits the ACM to switch  504  over PSTN  510 . Those skilled in the art will appreciate that some conventional steps for setting up and placing a call will not be discussed for the sake of brevity. 
     Switch  504  processes the ACM to generate a call progress message. Switch  504  transmits the call progress message to calling device  502 . Calling device  502  processes the call progress message to determine a call progress tone. Examples of call progress tones are dial tone, busy tone, ringback tone, error tone, and re-order. Calling device  502  then generates the call progress tone and plays audible sounds that represent the call progress tone. 
       FIG. 8  depicts a process  800  executed by switch  504  to provide call progress tones for the call in an example of the invention. Switch  504  receives the ACM from switch  506 . Switch  504  processes the ACM to determine a proper call progress tone. Switch  504  then determines if calling device  502  is configured to generate call progress tones. To make this determination, switch  504  searches database  512  for calling device  502 . Database  512  contains a list of calling devices that are configured to generate call progress tones. 
     If switch  504  does not find calling device  502  in database  512 , then switch  504  operates in the conventional manner described in the prior art. In the conventional manner, switch  504  generates the proper call progress tone and transmits the proper call progress tone to calling device  502 . Switch  504  maintains the call to transmit the proper call progress tone. Process  800  then ends. 
     If switch  504  does find calling device  502  in database  512 , then switch  504  determines if calling device  502  is configured to generate the proper call progress tone. Database  512  lists the call progress tones that each calling device can generate. If calling device  502  is not configured to generate the proper call progress tone, then switch  504  operates in the conventional manner described in the prior art. 
     If calling device  502  is configured to generate the proper call progress tone, then switch  504  generates a call progress message based on the call progress tone. Switch  504  transmits the call progress message to calling device  502 . Switch  504  then releases the call. Process  800  then ends. Those skilled in the art will appreciate that calling device  502  could also release the call instead of, or in addition to, switch  504 . 
       FIG. 9  depicts a process  900  executed by calling device  502  to generate call progress tones in an example of the invention. Calling device  502  receives the call progress message from switch  504 . Calling device  502  processes the call progress message and performs a table look-up in a call progress tone table based on the call progress message. If calling device  502  locates the call progress message in the call progress tone table, then calling device  502  determines the proper call progress tone based on the call progress message. Calling device  502  then generates the proper call progress tone and plays audible sounds that represent the proper call progress tone. Process  900  then ends. 
     If calling device  502  does not locate the call progress message in the call progress tone table, then calling device  502  determines a default call progress tone. Calling device  502  generates the default call progress tone and plays audible sounds that represent the proper call progress tone. Process  900  then ends. 
     Those skilled in the art will appreciate that the above-described switch  504  could be comprised of instructions that are stored on storage media.  FIG. 10  shows an example of switch  504 . Switch  504  is comprised of processor  1002  and storage media  1004 . The instructions can be retrieved and executed by processor  1002 . Some examples of instructions are software, program code, and firmware. Some examples of storage media  1004  are memory devices, tape, disks, integrated circuits, and servers. The instructions are operational when executed by processor  1002  to direct processor  1002  to operate in accord with the invention. The term “processor” refers to a single processing device or a group of inter-operational processing devices. Some examples of processor  1002  are computers, integrated circuits, and logic circuitry. Those skilled in the art are familiar with instructions, processors, and storage media. Switch  504  includes database  512  that could be incorporated within storage media  1004 . 
     Those skilled in the art will also appreciate that the above-described calling device  502  could be comprised of instructions that are stored on storage media.  FIG. 11  shows an example of calling device  502 . Calling device  502  is comprised of processor  1102  and storage media  1104 . The instructions can be retrieved and executed by processor  1102 . Some examples of instructions are software, program code, and firmware. Some examples of storage media  1104  are memory devices, tape, disks, integrated circuits, and servers. The instructions are operational when executed by processor  1102  to direct processor  1102  to operate in accord with the invention. The term “processor” refers to a single processing device or a group of inter-operational processing devices. Some examples of processor  1102  are computers, integrated circuits, and logic circuitry. Those skilled in the art are familiar with instructions, processors, and storage media. Storage media  1104  could also store call treatment table  1106  for calling device  502 . 
     The following are exemplary operations of communication system  500  shown in  FIG. 5 . For a first example, assume that calling device  502  attempts to place a call to called device  508 , and called device  508  is busy. Switch  506  transmits an ACM, that contains a release value denoting that called device  508  was busy, to switch  504 . Switch  504  transmits a call progress message to calling device  502  and then releases the call. Calling device  502  processes the call progress message to determine the proper call progress tone. The proper call progress tone in this case is a slow busy signal. Calling device  502  generates a slow busy signal and plays the audible slow busy signal. 
     For a second example, assume that calling device  502  attempts to place a call to called device  508 , and all trunks between switch  504  and switch  506  are busy. Switch  504  determines that the trunks are busy. Switch  504  transmits a call progress message to calling device  502  and then releases the call. Calling device  502  processes the call progress message to determine the proper call progress tone. The proper call progress tone in this case is a fast busy signal. Calling device  502  generates a fast busy signal and plays the audible fast busy signal. 
       FIG. 12  illustrates a process  1200  for installing new call progress tones in calling device  502 . Calling device  502  first connects to a provider that is configured to provide call progress tones. The connection could be, for example, to a switch, a signal processor, or a server. Calling device  502  then requests a new call progress tone. Calling device  502  receives the new call progress tone from the provider. Calling device  502  updates the call progress tone table by adding the new call progress tone to the call progress tone table. Process  1200  then ends. 
       FIG. 13  illustrates a process  1300  for updating database  512 . Database  512  could be updated when a new calling device is added, or when a calling device installs a new call progress tone. In either case, a calling device connects to switch  504 . Switch  504  transmits a query to the calling device for call progress tone information. Switch  504  receives a response from the calling device that includes the call progress tone information. If the calling device is new, then switch  504  adds the calling device and the corresponding call progress tone information to database  512 . If the calling device is not new, then switch  504  locates the calling device in database  512  and updates the entry in database  512  with the call progress tone information. Process  1300  then ends. 
     Those skilled in the art will appreciate variations of the above-described embodiments that fall within the scope of the invention. As a result, the invention is not limited to the specific examples and illustrations discussed above, but only by the following claims and their equivalents.