Multi-media interface - Patent Review 5497373

What is claimed is:

1. A universal multi-media system interface for interfacing various communication networks with a multi-media messaging system that provides communications services to subscribers, comprising:

parallel signal processors, each processor selectively processing in parallel messages in a particular communication format in accordance with a reconfigurable protocol conversion algorithm;

a line interface module connecting the multi-media interface to the various communications networks for dividing messages received over multiple communications links in the communications networks into frames, each frame including a plurality of time slots;

a time slot interchanger for receiving framed messages from the line interface module and selectively routing various time slots of information to one or more of the parallel signal processors; and

a supervisory processing unit for selectively downloading protocol conversion algorithms from the multi-media messaging system in real time into one or more of the parallel processors while continuing to process messages in another of the parallel processors to reconfigure the one or more of the parallel processors in real time to selectively perform protocol conversions on the selectively routed time slots, wherein the multi-media messaging system provides call processing services to subscribers using different types of communications media.

2. The system according to claim 1, wherein the messaging services include one or more of the following: voice messaging, facsimile messaging, voice mail, facsimile mail, wide area paging, video messaging, video mail, interactive voice messaging, and short messaging services.

3. The system according to claim 1, further comprises:

a line interface module for interfacing the multi-media interface with one or more time division multiplex (TDM) lines in the communications network, each TDM line having multiple time slots, and

a time slot interchanger for routing time slots between the line interface module and the parallel processors.

4. The system according to claim 3, wherein the time slot interchanger is configured to selectively route only those time slots to each parallel processor that actually requires the protocol conversion currently being performed by that parallel processor.

5. The system according to claim 3, wherein each parallel processor performs a subscriber protocol conversion on multiple time slots in parallel.

6. The system according to claim 3, wherein the time slot interchanger routes a single time slot to plural parallel processors.

7. The system according to claim 1, wherein the parallel processors are digital signal processors.

8. The system according to claim 1, wherein the plural types of communication media include one or more of the following: voice, facsimile, and video, and common channel signalling.

9. The universal multi-media system interface according to claim 1 further comprising:

a plurality of first shared memories, each first shared memory accessible by one of the signal processors and by the supervisory processing unit, and

a second shared memory accessible by the supervisory processing unit and by the multi-media messaging system, wherein the first and second shared memories are used in the real time reconfiguration of the one or more parallel signal processors.

10. The universal multi-media system interface according to claim 9, wherein the real time reconfiguration includes real time switching of protocol conversion algorithms processors and real time exchange of data to and from the parallel signal processors.

11. A messaging system responsive to different types of communications media, comprising:

a host messaging center for providing messaging services;

a plurality of messaging subscribers sending messaging information over one or more communications networks using different subscriber communication protocol formats; and

a multi-media interface connected to the host messaging center and the one or more communication networks, including:

parallel processors for converting in parallel messaging information received in the different subscriber protocol formats into a host protocol format employed by the host messaging center and for converting messaging information in the host protocol format into corresponding different subscriber protocol formats, each parallel processor performing one of a plurality of different subscriber protocol conversions on messaging information to/from plural subscribers;

a plurality of memories each memory being dedicated to one of the parallel processors; and

a central processor connected to the plurality of memories, wherein information is transferred between each parallel processor and the central processor using the parallel processor's dedicated memory.

12. The system according to claim 11, wherein the central processor configures each parallel processor to perform a particular one of the plurality of different subscriber protocol conversions by transferring program data for executing the particular subscriber protocol conversion to the parallel processor through the parallel processor's dedicated memory.

13. The system according to claim 12, wherein the central processor configures each parallel processor in real time.

14. The system according to claim 12, wherein the central processor reconfigures one or more of the parallel processors in real time to perform a different subscriber protocol conversion.

15. The system according to claim 11, wherein each memory includes plural data areas for storing messaging information in the host protocol format with each data area having a first buffer and a second buffer and wherein stored messaging information is transferred by one of the parallel processor and the central processor and is received by the other of the parallel processor and the central processor using the first and second buffers.

16. The system according to claim 15, wherein the dedicated memory includes a queue that stores for each data area corresponding identification data for identifying and accessing the data area in the dedicated memory.

17. A messaging system responsive to different types of communications media, comprising:

a host messaging center for providing messaging services;

a plurality of messaging subscribers sending messaging information over one or more communication networks using different subscriber communication protocol formats; and

a multi-media interface, connected to the host messaging center and the communication networks, including parallel processors for converting in parallel messaging information in the different subscriber protocol formats into a host protocol format and for converting in parallel messaging information in the host protocol format into corresponding different subscriber protocol formats,

wherein the host messaging center dynamically reconfigures the multimedia interface in real time, wherein the host messaging center configures the multi-media interface to perform selected protocol conversions using a software service table provided at the multi-media interface that correlates a subscriber communications channel with one or more call processing services and wherein one or more of the parallel processors performs protocol conversions in accordance with the software service table.

18. The system as in claim 17, wherein the host messaging center dynamically reconfigures the multi-media interface by changing entries in the software service table.

19. The system as in claim 17, wherein entries in the software service table selectively route messaging information corresponding to the subscriber communications channel to/from the one or more processors.

20. The system as in claim 17, wherein a single channel is correlated with plural processors.

21. The system as in claim 17, wherein a single one of the parallel processors is correlated with plural channels such that messaging information from the plural channels is converted into the host protocol format simultaneously by the single processor.

22. The system as in claim 21, wherein the single processor simultaneously converts messaging information from three or more channels into the host protocol format.

23. The system as in claim 17, the multi-media interface further comprising:

a line interface module for interfacing the multi-media interface with a time division multiplex (TDM) line in the communications network, the TDM line having multiple time slots with each time slot corresponding to a subscriber communications channel, and

a time slot interchanger for routing time slots between the line interface module and the parallel processors.

24. The system as in claim 23, wherein the time slot interchanger is configured by the software service table to route only those time slots to each parallel processor that require the protocol conversion currently being performed by that parallel processor.

25. A messaging system responsive to different types of communications media, comprising:

a plurality of messaging subscribers transmitting messaging information over one or more communications networks using different subscriber communication protocol formats;

a host messaging center for providing messaging services to the subscribers; and

a multi-media interface, connected to the host messaging center and the communication networks, including:

parallel processors for converting messaging information in the different subscriber protocol formats into a host protocol format employed by the host messaging center in accordance with protocol conversion algorithms, each protocol conversion algorithm corresponding to one of the different subscriber protocol formats;

parallel memories, each of the parallel processors being associated with one of the memories; and

a central processor connected to the parallel memories and the host messaging center,

wherein conversion algorithms are selectively loaded into each of the parallel processors by the central processor from the host messaging center using the associated memory and a different conversion algorithm is loaded in real time into one or more of the parallel processors in response to commands from the host messaging center.

26. The system as in claim 25, wherein plural ones of the parallel processors convert pulse code modulated voice signals into a compressed format.

27. The system as in claim 25, wherein the associated memories are dual port memories shared by the associated processor and the central processing unit with data being communicated asynchronously between each of the parallel processors and the central processing unit using the associated shared memory.

28. The system as in claim 27, wherein each shared memory includes plural data transfer buffers, the associated processor storing data for the central processing unit in one of the transfer buffers and retrieving data from the central processing unit from another of the transfer buffers.

29. The system as in claim 28, wherein each data buffer is managed by a corresponding envelope that points to the location in the shared memory of the corresponding data buffer and wherein the envelopes are stacked in an envelope queue and used by the corresponding processor and the central processing unit to access information stored in the data buffer.

Description Submit all comments and votes

FIELD OF THE INVENTION

The present invention relates to providing multi-media messaging services over fixed telephone, radiotelephone, paging and other types of communication networks, and more particularly, to a multi-media interface.

BACKGROUND AND SUMMARY OF THE INVENTION

The current and continuing trend in the telecommunications industry is toward providing a wide variety of information and communication services (hereafter "messaging services") over various communications networks to remote subscribers having diverse analog and digital communications equipment in an integrated fashion. Such communication services include, for example, voice messaging, facsimile messaging, wide area paging, electronic mail, electronic document interchange, interactive voice response, audio text, speech synthesis, speech recognition, video messaging/video mail, etc.

To provide these messaging services, different types of communications media from different types of communications equipment and processing protocols must be interfaced to a single host system or messaging center that provides the messaging services. For example, the host messaging center might notify a subscriber of various messages (e.g., pages, voice mail messages, etc.). To perform these services, protocol conversions must be performed between the format employed by the host messaging center and the various telecommunications formats employed by diverse subscriber equipment. One example is the protocol conversion between voice information received in pulse code modulated (PCM) format to/from a data compressed format in which the voice information is processed and stored at the host messaging center.

Companies that provide information services over the public telephone network generally use hardwired transceiving and protocol conversion equipment dedicated to a particular type of equipment and communications format/protocol. This dedicated hardware approach has obvious drawbacks in terms of cost, flexibility, and adaptability. For example, dedicated hardware cannot be readily modified to increase data throughput; nor can it be adapted to handle communication protocols corresponding to new telecommunication equipment and services. To support multiple type of messaging services to a diverse set of communications equipment, costly replacements and new hardwire designs of dedicated hardware are required.

More recently, digital signal processing has been used to process a digital communications trunk line as described for example in U.S. Pat. No. 4,991,169 to Davis et al. Unfortunately, even though the digital signal processing in Davis adds some flexibility in converting different types of signal formats, it lacks sufficient channel handling capacity and data throughput for large scale and/or sophisticated multi-media messaging applications. While Davis might be suitable for some very simple conversion algorithms such as DTMF detection and a low capacity system, Davis' system is severely limited with respect to the number of communication channels that can be handled. Nor can Davis' system perform different protocol conversion processes in parallel. Moreover, Davis lacks the ability to dynamically change the protocol conversion algorithm executed by the DSP system in real time while still processing channels.

What is needed is a multi-media interface that overcomes these deficiencies in terms of much increased handling and throughput capacity and increased system adaptability/flexibility to different communication media types to provide subscribers with a variety of multi-media communications options in real time.

The present invention provides a multi-media interface (MMI) that universally and flexibly supports present (and contemplated) messaging applications including voice mail, facsimile mail, electronic mail, interactive voice response, DTMF tone detection, automated attendant services, audio text services, radio paging services, speech recognition/speech synthesis, voice recognition, video messaging, video mail, common channel signalling, short messaging services, etc. The MMI interfaces multi-media voice and data between various communication networks including for example the public switched telephone network (PSTN), the packet switched public data network (PSPDN), and the cellular telephone and paging networks at a very high data throughput. In order for the host messaging center to provide these services to multi-media subscribers communicating over various communications networks, the multi-media interface makes necessary protocol conversions for different telecommunications protocols corresponding to various types of telecommunications media (and associated control signalling) which may include, for example, speech in analog form, speech data in pulse code modulated (PCM) form, modem data in PCM form, data in analog form modulating sinusoidal carriers, and data in various digital forms associated with a variety of protocol standards. A programmable line interface module and a time slot interchanger frame the received information and selectively route various time slots of information from the communications network to/from multiple parallel digital signal processors (DSPs) (each with its own dual port, high speed RAM) to perform various protocol conversions. A local central processing unit (CPU) controls and coordinates the line interface, time slot interchanger, and DSPs via a local bus in accordance with commands from the host messaging center.

The programmable line interface module links subscriber communications information received from a communications network through time division multiplex (TDM) channels (or time slots) corresponding to digital carrier systems for North American (T1) and European (E1) standards. The line interface module frames and synchronizes the incoming raw data, PCM voice, modem, and other media formats and routes that information to the time slot interchanger which then connects a particular time slot channel to one of the multiple, parallel digital signal processors, e.g. six. Functioning as the interface between the host messaging center and digital carrier channels routed through the time slot interchanger, the DSPs perform virtually any kind of necessary protocol conversion so that the information can be processed and stored in the protocol format of the host. For example, incoming quantized voice samples in A-PCM or .mu.-PCM format may be converted using regular pulse excitation long term prediction (RPE-LTP) algorithms into a compressed data format used by the host messaging center.

The multiple parallel digital signal processors operate completely independently of each other and communicate with the local CPU via the local CPU bus using their dedicated, dual port RAMs. In response to channel service requests from time slots over multiple time division multiplex communication lines, each DSP individually processes in parallel multiple time slots of information in the process of handling channel service requests. As a result, in an example where each DSP performs a voice protocol conversion algorithm such as that just described for six time slots, if six parallel DSPs were all processing voice in this manner, the MMI would be handling thirty-six time slots simultaneously.

At initial system configuration and also in real time (if system needs demand), the local CPU dynamically allocates one or more of the DSPs to handle different types of protocol conversions for multiple communications channels. For example, with each digital signal processor processing multiple time slots of information at one time (i.e. six or seven time slot channels for each TDM frame), five DSPs could be configured to handle voice conversion processing for twenty-five voice channels, and one DSP could be configured to handle protocol conversions for five facsimile channels.

Depending upon what services are required by a particular caller, the local CPU downloads appropriate protocol conversion algorithms from the host messaging center to a selected one or more DSPs using a service configuration table that is downloaded from the host messaging center. Taking a high level example in a voice mail context, if a caller presses a DTMF button during a voice prompt indicating a Group III facsimile service request, the host messaging center commands the MMI to route this Group Ill facsimile call to one or more of the DSPs currently configured to provide the necessary protocol conversions for Group III facsimile. In this way, the converted facsimile information can be stored in data compressed binary form in the host messaging center under the caller's mailbox identification number.

If a caller wishes to interact with the host messaging center via interactive voice rather than pushbutton or keyboard and that service is not presently being supported by one of the DSPs, the appropriate voice recognition and voice synthesis software is downloaded from the host center to one or more of the DSPs via a VME interface, the local CPU, and the DSP's corresponding dual port RAM. The DSP(s) is(are) then configured with the necessary software to perform the protocol conversions required so that the host messaging center and caller can interact by voice. Other software may be similarly downloaded in real time to any of the multiple DSPs to ensure that other messaging services such as voice mail, facsimile mail, etc. are provided to multiple diverse subscribers with fast and efficient protocol conversion.

Because the architecture of the multi-media interface is modular, it is readily adaptable to handle any other types of protocols to permit handling of new data and providing of new messaging/telephony services without changing its basic architecture. For example, more parallel DSPs could be added to provide greater capacity, greater throughput, and/or new types of call services requiring new protocol conversions. In addition, the DSPs can be configured in real time to adapt to system needs so that if more data processing capacity is now required for an increase in facsimile related services and voice related services are down, one or more DSPs could be removed from voice protocol conversion and dedicated to facsimile protocol conversion. Alternatively, the DSPs could be replaced with other processing hardware more suited to a particular application. And as described above, if a new communications medium is added to the system, e.g. video image signals for video conferencing, the corresponding protocol conversion software is readily downloaded into one or more of the parallel DSPs to accommodate these new communications medium signals.

These and other features, advantages, and benefits of the present invention will be more fully understood by those of ordinary skill in the art from the following written description and claims read in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a function block diagram overviewing a multi-media messaging system;

FIG. 2 is a function block diagram of the multi-media interface according to the present invention;

FIG. 3(a) is a schematic drawing illustrating the manner in which time slot information from a TDM line is handled by the MMI for purposes of providing channel information to the messaging host;

FIG. 3(b) is a call processing service table describing the MMI configuration illustrated in FIG. 3a;

FIG. 4(a) is an exemplary service table that may be used in conjunction with the present invention;

FIG. 4(b) is a flow chart diagram illustrating exemplary MMI service configuration procedures;

FIG. 5 shows how a service table maybe used to configure the time slot interchanger;

FIG. 6 is a diagram showing the time-slot/offset routing between the time slot interchanger, the DSPs, and the MMI CPU using the dual port memories;

FIGS. 7 and 8 illustrate the configuration of the dual port shared memories and the use of envelope queues to access data buffer areas in the shared memory;

FIG. 9 illustrates the command protocol between each DSP and the MMI CPU; and

FIG. 10 is a flow chart diagram illustrating an alternate buffering procedure for transferring data buffers from a DSP to the CPU.

DETAILED DESCRIPTION OF THE INVENTION

In the following description, for purposes of explanation and not limitation, specific details are set forth such as particular architectures, interfaces, techniques, etc. in order to provide a thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well known devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

The present invention receives and processes signals transmitted from various different types of telecommunications equipment (multi-media) over the public, cellular, and other communication networks in a variety of transmission formats--both analog and digital. For example, voice signals, Group III facsimile, and other analog data modem signals are typically modulated by frequency or phase shift keys and then scaled or companded to conform with analog telephone standards like A-law or .mu.-law PCM format according to CCITT G.711. In functional terms, this means that digital facsimile information converted and transmitted by the facsimile machine into analog tones for transmission on existing over telephone lines must be converted into digitized analog signals for long distance transmission. Of course, this system of digital-to-analog-to-digital conversion for transmission and then conversion back to analog and back to digital for a receiving facsimile to print the page is inefficient. However, most users still have old style telecommunication lines connecting their facsimile machines to digital communication networks and therefore use the Group III facsimile format. On the other hand, Group IV facsimile, ISDN LSPB, and SS7 signalling line protocols are transmitted digitally directly on the telephone line without companding or modulation and therefore are in a format that does not require converting the digital facsimile into modulated tones.

Consequently, the information on telephony lines is in two general types: continuous, noninterruptible signals (e.g. voice) and segmented interrupible signals (e.g. facsimile). These signals are formatted using one of many line protocols or a combination of line and data protocol types. Those protocols must be converted into binary signals that directly represent the data to be stored or processed in compressed form by the host messaging center.

FIG. 1 shows an general overview of a messaging system 6 for providing various messaging applications/services for virtually any type of telecommunications medium. A telephony front end 10 interfaces to various public and private communications networks 8 including for example the public switch telephone network (PSTN), the public cellular or mobile telephone network (PLMN), and the packet switched public data network (PSPDN) and provides the necessary interface between a subscriber's voice or data channel from the communications network 8 and the messaging system 6.

The multi-media interface (MMI) 12 performs the necessary protocol conversions of the information received in various telecommunications formats depending on among other things the subscriber's telecommunications equipment so that the host messaging center 14 can process and/or store that information in the host's data processing and storage format which preferably is in a compressed data format. Once converted, the relevant messaging information extracted from the communications channel is processed by the host 14 to deliver the particular messaging/telephony service requested by the subscriber. Information from the host 14 responding to the customer's service request is then converted back by the MMI 12 into the communications protocol format used by the subscriber and transmitted via the telephony front end 10 and communications network 8 to the subscriber. For example, voice messaging services require the MMI 12 to convert logarithmically encoded PCM (A-law or .mu.-law) data into a compressed standard data format processable by the host 14, (see as one example the (ETSI) GSM 6.10 standard), and expand the compressed data into log-PCM form for transmission back to the subscriber over the telephony network.

FIG. 2 is a more detailed function block diagram of the multi-media interface 12. MMI 12 may be a 6-U or a 9-U VME board that occupies one VME slot of a SUN work station operating platform upon which the entire messaging system shown in FIG. 1 is built. The MMI 12 includes a line interface module (LIM) 16 connected to one or more communications networks 8, a time slot interchanger 20, and six parallel digital signal processors (DSPs) 24-34 each having their own dedicated, dual port RAM 36-46. A central processing unit (CPU) 48 connects to each of the dual port RAMs 36-46, the time slot interchanger 20, and the line interface module 16 over a local CPU bus 22. An EPROM memory 52, shared memory 54, a VME bus interface 56, and VME bus 58 are used in communications with host 14. Interface 56 is a conventional VME revision C interface whose specification is available from the VMEbus International Trade Association, and has an address A24/data D32 and A32 bus master interface and an A24/D32, A32/D32, and A16/D16 slave interface to the VME bus 58. The host messaging system 14 includes one or more industrial computers, such as the SUN/6XXMp, SUN-SpAR