Sms format mapping for different cellular systems

The present invention generally relates to wireless communications, and in particular to methods and devices for providing short message services in different mobile communication systems.

Code division multiple access (CDMA) modulation is one of several technologies that facilitates communication with a large number of system users. Amplitude modulation schemes such as Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Global System for Mobile Communications (GSM), or Amplitude Companded Single Sideband (ACSSB) Other technologies such as are also available, but CDMA has an advantage over these other modulation technologies. The use of CDMA technology in multiple access communication systems has been transferred to the assignee of this application and is incorporated herein by reference in a US patent entitled "Spread Spectrum Multiple Access Communication System Using Satellite Or Terrestrial Repeaters". It is disclosed in No. 4,901,307 (Patent Document 1).

In US Pat. No. 4,901,307, a large number of mobile phone system users, each with a transceiver, use code division multiple access (CDMA) spread spectrum communication signals to satellite repeaters or ground base stations (cell base stations, or). Multiple access technologies that communicate via (also known as cell sites) are disclosed. When using CDMA communication, the frequency spectrum can be reused many times. This allows for increased system user capabilities. The result is that the use of CDMA technology results in higher spectral efficiency than can be achieved with other multi-access technologies.

Although traditional mobile phone systems use analog FM modulation technology, the available frequency bands are generally divided into channels with a bandwidth of 30 KHz. This system service area is divided into geographically variable size cells. The available frequency channels are usually divided into sets, each containing an equal number of channels. This frequency set is assigned to cells to minimize the possibility of interference between channels. For example, consider a system in which there are seven frequency sets and the cells are hexagons of equal size. The frequency set used in one cell is not used in the six neighbors closest to or around that cell. Moreover, the frequency set in one cell is not used in the 12 neighbors next to that cell.

A more difficult situation manifests itself in the movement of a mobile station from another cell system to a cell served by the base station. A complex factor in such "intersystem" handoffs is that neighboring mobile systems often have different characteristics. For example, adjacent portable systems often operate at different frequencies and maintain different levels of base station output power, or pilot intensity. Moreover, adjacent mobile systems may require different message structures, even for similar types of messages.

For example, the so-called GSM standard has no mechanism for soft handoff. Therefore, problems arise when handing off calls from a CDMA network to a GSM network using an air interface. In addition, GSM certification is not done. This is because the CDMA2000 mechanism cannot transfer the data required for GSM authentication. Encryption in GSM is different from encryption in CDMA2000.

In another example, there is currently no mechanism for handling SMS and SMSC information using an air interface from a CDMA network to a GSM network. That is, when an SMS message is sent from mobile, the network needs to know the SMSC address to send the SMS message. Similarly, standard GSM SMSC information is not forwarded. This is because the CDMA mechanism cannot transfer the data needed to handle GSM SMSC address information. In addition, the standard CDMA SMS message format (IS-637) is not handled by standard GSM networks. This is because the GSM mechanism cannot transfer the data needed to handle standard CDMA SMS messages.

One way to address this issue is to modify GSM to achieve handoffs for non-GSM systems, such as CDMA systems. Another way to deal with this problem is to modify the CDMA to handle traditional SMSC messages. However, both CDMA and GSM are relatively well-established systems, and operators and equipment providers are reluctant to make expensive changes to existing equipment to accommodate nearby incompatible systems. If new messages are added to the air interface to support dual-mode mobile stations, changes must be made to support the new messages using existing hardware. This is clearly an undesirable form from the operator's and equipment provider's point of view.<patcit num="1"><text>U.S. Pat. No. 4,901,307</text></patcit><patcit num="2"><text>U.S. Patent Application No. 60 / 350,829</text></patcit><patcit num="3"><text>U.S. Patent Application No. 60 / 354,086</text></patcit><patcit num="4"><text>U.S. Patent Application No. 10,076,831</text></patcit><patcit num="5"><text>U.S. Patent Application No. 60 / 340,356</text></patcit><patcit num="6"><text>U.S. Patent Application No. 10 / 077,556</text></patcit>

The present invention addresses the problems described above.

In the GSM network, SMS messages sent from mobile stations are addressed to the destination SMS service center. This service center is available from GSM SIM cards, from previously received SMS messages, or as input from users. The SMSC address is used by the GSM MSC to route the message to the appropriate SMSC.

However, there is a problem that there is currently no mechanism for handling SMS and SMSC messages using an air interface from a CDMA network to a GSM network. No GSM SMSC messaging is done. This is because the CDMA mechanism cannot transfer the data needed to handle GSM SMSC messaging. Similarly, the standard CDMA SMS message format (IS-637) is not handled by standard GSM networks. This is because the GSM mechanism cannot transfer the data needed to handle standard CDMA SMS messages.

The solution to this problem is to include proper translation of CDMA SMS messages and SMSC addressing so that the GSM service network 140 can receive SMSC messages in standard GSM formats and configurations. That is, it becomes clear to the GSM core network 120 that the original SMS message arrived through the CDMA air interface and was modified by the hybrid MSN132. Similarly, the solution to this problem also translates standard GSM SMSC messages into SMS messages to be interpreted by the CDMA air interface. As such, it will also be revealed in the GSM core network 120 that SMSC information has been converted to standard CDMA SMS messaging and directed to CDMA-based mobile stations.

According to one aspect of the invention, there is provided a method of mapping short message service (SMS) information from a first communication system to a corresponding message in a second, different mobile system. The method comprises receiving SMS information in a format required by the first communication system and mapping the SMS information to a format required by the second communication system. ing. Further, in response to the request from the second communication system, additional information is added if necessary, or irrelevant information is deleted if necessary. In one embodiment, the first mobile communication system is a CDMA system and the second mobile communication system is a GSM system.

The above-mentioned and additional features of the invention are described with details in the claims and, along with their advantages, are typical embodiments of the invention given with reference to the accompanying drawings, as described below. It will become clearer from the examination of the detailed description of.

FIG. 1 is a schematic diagram of a typical mobile phone system 100. The system illustrated herein may generally use any of a variety of multi-dimensional access modulation techniques to facilitate communication between a large number of system mobile stations or mobile phones and base stations. Such multi-access communication system technologies include time-division multiple access (TDMA), Global System for Mobile Communications (GSM), General Packet Radio Service (GPRS), and high-speed circuit-switched data systems (GPRS). iDEN: High Speed Circuit Switched Data), Frequency Division Multiple Access (FDMA), Code Division Multiple Access (CDMA), TS Code Division Multiple Access (TSCDMA), Orthogonal Frequency Division Multiple Access (OFDM), and Amplitude Enlargement Single Sidewave Includes band-like amplitude modulation schemes.

For purposes of illustration, FIG. 1 shows a communication system as a combination of a CDMA-based system and a GSM-based system. It should be understood that any two communication systems, such as those described above, can be applied.

Mobile station 104 illustrates a GSM / GPRS device with a subscriber identification module 106. Mobile station 108 illustrates a GSM / CDMA 2001x device with a subscriber identification module 110. Mobile station 108 is equipped with software and / or hardware changes from traditional GSM or CDMA mobile stations, allowing this device to interact with both GSM and CDMA infrastructure. .. Mobile station 112 illustrates a CDMA 2000x device with a subscriber identification module 114.

Mobile stations 104,108,112 are wireless communication devices such as mobile phones, PDAs, computers, or other wireless devices capable of wireless communication of voice or data information. SIM cards 106,110,114 can operate with a CDMA 1x handset and can be standard GSM SIM cards capable of receiving and responding to signals from base stations within both CDMA and GSM mobile systems. The GSM SIM card 108 integrated into the CDMA 1x handset is a US patent provisional application 60 / 350,829 (Patent Document 2) filed on January 17, 2002, and a US patent filed on February 1, 2002. It is discussed in Provisional Application No. 60 / 354,086 (Patent Document 3). Both of these documents have been switched to US Patent Application No. 10,076,831 (Patent Document 4) filed on February 14, 2002, where they are specifically enclosed as references. SIM cards 106,110,114 can also be special SIM cards configured to operate with one or more wireless systems.

The mobile station 104 is communicably connected to the radio access network (RAN) 116. In one embodiment, the RAN116 is a standard GSM or GSM / GPRS RAN, a standard GSM-based base transceiver subsystem (BTS) and a standard GSM base station controller (BSC) (not shown). And have.

Mobile stations 108,112 are communicably connected to a radio access network (RAN) 120. Mobile station 108 is communicably connected to both RAN116 and RAN120. In one embodiment, RAN120 is a CDMA 1x RAN, as described in US Patent Provision 60 / 340,356 (Patent Document 5) filed on December 14, 2001. This provisional application was switched to US Patent Application No. 10 / 077,556 (Patent Document 6) filed on February 14, 2001, and was assigned to the same assignee as the present invention, which is specifically enclosed here as a reference. Will be done. The RAN120 is a standard CDMA2000 or CDMA2000 1x RAN with a standard CDMA-based base transceiver subsystem (BTS) and a standard CDMA-based base station controller (BSC) (not shown). ing.

The GSM RAN116 is connected to the GSM SMSC / SGSN124 via interface 128. The GSM SMSC / SGSN124 is connected to the GSM switching network 136 using MAP, ISUP, and GTP interfaces and protocols.

The CDMA RAN 120 is connected to the GSM1x mobile switching node (MSN) 132 via a standard IO54 interface / protocol 136. The MSN 132 is preferably a hybrid MSN connected to both the RAN 120 and the GSM switching network 136. The GSM switching network 136 is connected to the rest of the GSM service network 140. The MSN 132 can communicate with both the RAN 120 and the GSM service network 140 by mapping messages that are presumed to be the format and configuration in one mobile communication system to the format and configuration in a second mobile communication system. For example, if one communication system is a GSM system and the second communication system is a CDMA2000-1x system, the hybrid MSN132 will change from the configuration and format known in the GSM system to the one known in the CDMA1x system, etc. Map.

In the GSM network, SMS messages sent from mobile stations are addressed to the destination SMS service center. This service center is available from GSM SIM cards, from previously received SMS messages, or as input from users. The SMSC address is used by the GSM MSC to route this message to the appropriate SMSC.

However, there is a problem that there is currently no mechanism for handling SMS and SMSC messages using an air interface from a CDMA network to a GSM network. No GSM SMSC messaging is done. This is because the CDMA mechanism cannot transfer the data needed to handle GSM SMSC messages. Similarly, the standard CDMA SMS message format (IS-637) cannot be handled by standard GSM networks. This is because the GSM mechanism is unable to transfer the data needed to handle standard CDMA SMS messages.

For example, if an SMS message from a mobile is sent from a mobile station to an infrastructure network, the network needs to know which SMSC sends the SMS message. Similarly, when a mobile station sends an SMS knowledge message, the network needs to know the SMSC address to which this knowledge should be forwarded. This information resides on the GSM SIM card but cannot be sent via the air interface. This is because the CDMA2000 1x SMS format does not provide a mechanism for including SMSC addresses in SMS messages. Therefore, the MSC116 needs to modify the SMS message to include the SMSC address.

If new messages or new formats are added to the air interface supported by the dual-mode mobile station, the changes must be made to support these new messages. This is not desirable.

The solution to this problem is to include proper translation of CDMA SMS messages and SMSC addressing. This allows the GSM service network 140 to receive SMSC messages in standard GSM formats and configurations. That is, it becomes clear to the GSM core network 120 that the original SMS message arrived through the CDMA air interface and was modified by the hybrid MSN132. Similarly, the solution to this problem is to further translate standard GSM SMSC messages into SMS messages that are interpreted by the CDMA air interface. As such, it will also be apparent to the GSM core network 120 that SMSC information has been converted to standard CDMA SMS messaging and directed to CDMA-based mobile stations.

Figure 2 (a) shows the process 200 performed to convert a CDMA SMS message into a GSM SMSC message. SMS messages from CDMA mobile stations are received by MSN132204. The CDMA SMS information is then mapped to a format recognized by the GSM system208. However, this may be inadequate as GSM systems may require additional SMSC address fields. Therefore, an additional SMSC address is added by MSN132 212. The mapped GSM SMS information is then sent along with the added SMSC address information (as needed) 216.

If you embed the SMSC address in the SMS address field, the SMSC address is saved and obviously expanded. Therefore, the CDMA base station apparently routes the SMS message without any modification. In addition, the presence or absence of the SMSC address allows the mobile station 104 and MSC116 to determine where the message originated.

Figure 2 (b) shows the process 250 performed to convert a GSM SMSC message into a CDMA SMS message. First, GSM SMSC information is received 254. The GSM SMSC information is then mapped to the CDMA SMS information 258. However, this is superfluous because CDMA systems do not require the SMSC address field. Therefore, the additional SMSC address is removed262. Then the mapped CDMA SMS information is sent 266.

An SMS message originating from a mobile contains a destination address, which is the address of the entity to which this SMS message is directed. The SMSC address is then added to this destination address field. Figure 3 shows the SMS message element 300. The SMS message element consists of a parameter identifier field 304, a parameter length field 308, a source or destination address section 312, and an SMSC address section 316.

The iDEN system utilizes the GSM-based MAP interface protocol. SMS messages are translated or mapped in much the same way as described above.

In one embodiment, the parameter identifier 304 may be a message sent by a mobile station. The parameter length 308 is the size (in bytes) of all the fields to follow. In one embodiment, the destination address 312 is on the forwarding layer and the SMSC address section 316 is on the relay layer. The destination address 312 consists of many fields, including digit mode 320, number mode 322, number type 324, number plan 326, number field 328, character 330, and spare field 332.

The SMSC address section 316 is tentative and consists of an SMSC address length field 334, an extended field 336, an address field property 338, a numbering plan field 340, a BCD field 342, a BCD 2N field 344, and a 0xF field 346. ..

The size of each character 330 is determined based on the digit mode 320, number mode 322, number type 324, and number plan 326. The numeric field 328 indicates the number of character fields 330. Therefore, the size of the conventional destination address is determined by the mobile station. If this size is less than the parameter length 308, the mobile station determines that the SMS address attached to the destination address parameter exists. The mobile station then proceeds with the rest of the destination address parameters to determine the SMSC address.

In one embodiment, the mobile station inserts a default value if the SIM does not have an SMSC address, or if there is no SMSC address that can be inserted into an SMS message. If the MSN receives an SMS message with this default value, the MSN forwards this SMS message to the default SMSC (if any). Therefore, the presence of the SMSC address length field should also indicate to MSN that the mobile station is a GSM1x mobile station and that the user data field is properly coded. However, if an SMS message is received without an SMSC address, MSN considers that this SMS message is a CDMA SMS message (IS-637) and will process it accordingly.

Also described is a device that translates short message service (SMS) information from a first communication system into corresponding messages in a second different mobile system. This device may be part of MSN. The device maps the input configured to receive SMS information in the format required by the first communication system and the SMS information into the format required by the second communication system. To add additional information if necessary, or remove irrelevant information if necessary, at the request of the mapper connected to the input and the second communication system connected to the mapper. It has additional / removed elements configured as such.

Therefore, novel and improved methods and devices for the interoperability of SMS messaging between communication systems have been described. Those skilled in the art will appreciate that these information and signals are represented using a variety of different techniques and techniques. For example, the data, instructions, commands, information, signals, bits, symbols, and chips cited in the above description may be voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or fine particles, or any of these. It can be represented by a combination.

This knowledge allows the various illustrated logic blocks, modules, circuits, and algorithm steps related to the examples disclosed herein to be applied as electronic engineering hardware, computer software, or a combination thereof. Will be understood further. To articulate the interoperability of hardware and software, various illustrated parts, blocks, modules, circuits, and steps have been generally described for their functionality. Whether these functions are applied as hardware or software depends on specific application examples and design conditions imposed on the entire system. A skilled technician can perform the above-mentioned functions by making changes according to each specific application. However, this application decision should not be construed as deviating from the scope of the present invention.

The various indicated logic blocks, modules, and circuits described in connection with the embodiments described above are also implemented, including general purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), and fields. It can be run with a programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination designed to achieve the functionality described above. Although it is possible to use a microprocessor as a general-purpose processor, it is also possible to use a conventional processor, controller, microcontroller, or state device instead. Processors can also be implemented as a combination of DSPs and microprocessors, multiple microprocessors, one or more microprocessors connected to a DSP core, or a combination of computing devices such as other configurations.

The steps of methods and algorithms described in connection with the embodiments disclosed herein are directly embodied by hardware, software modules executed by a processor, and combinations thereof. Software modules can be housed in RAM, flash memory, ROM, EPROM, EEPROM, registers, hard disks, removable disks, CD-ROMs, or other types of storage media known in the art. Suitable storage media are coupled to the processor so that the processor can read and write information from it. Alternatively, the storage medium can be essential to the processor. The processor and storage medium can be housed in an ASIC. The ASIC can also be stored in the user terminal. Alternatively, the processor and storage medium may be housed as discrete components in the user terminal.

The above description in the disclosed examples will allow any person skilled in the art to utilize or utilize the present invention. Various variations to these examples are also apparent to those skilled in the art, and the general principles defined herein also apply to other embodiments that do not deviate from the gist or scope of the invention. Can be applied. As described above, the present invention is not limited to the examples shown above, but is intended to correspond to a wide range that is consistent with the principles and novel features described herein.

<figref num="1">FIG. 1 is a diagram showing an outline of a hybrid mobile system.</figref><figref num="2">FIG. 2 (a) is a flowchart showing the conversion of a CDMA SMS message into a GSM SMS and an SMSC message, and FIG. 2 (b) is a flowchart showing the conversion of a GSM SMS and an SMSC message into a CDMA SMS message.</figref><figref num="3">FIG. 3 is a block diagram showing SMS and SMSC messaging between different mobile communication systems.</figref>

Code description

100 ... Mobile Phone System, 104 ... Mobile Station, 106 ... Subscriber Identification Module, 108 ... Mobile Station, 110 ... Subscriber Identification Module, 112 ... Mobile Station, 114 .. Subscriber Identification Module, 116 ... Radio Access Network, 120 ... Radio Access Network, 124 ... SGSN, 128 ... A Interface, 132 ... Hybrid MSN, 136 ... GSM Switching Network, 140 ... GSM Service Network