MXPA96003240A - Method of international identification of estacionmovil and system of signaling pararadiotelefonos and cellular systems - Google Patents

Abstract

The present invention relates to a signaling system for a radiotelephone system where messages including at least a first word and a second word are communicated between the base stations and the mobile stations, each mobile station being assigned an identification number (100 ) of mobile station including at least one country code (MCC) and a local number (MIN2, MIN1), said messages are each characterized by: a first word (Table 3) that includes a local number for a message or a first predetermined coded number, the first word has a plurality of second predetermined coded numbers for encoding a local number for a mobile station, and without including the first predetermined coded number in the plurality of second predetermined coded numbers, and a second word (Table 4) ) appended to a message when the first word includes the first predetermined encoded number, said second a word includes a plurality of third predetermined coded numbers to encode a local number for mobile station

Description

METHOD OF INTERNATIONAL IDENTIFICATION OF MOBILE STATION AND SIGNALING SYSTEM FOR RADIOTELEPHONES AND CELLULAR SYSTEMS Background of the Invention The present invention relates in general to radiotelephones and cellular systems, and more particularly to an international identification method of mobile station and signaling system for radiotelephones and cellular systems. Cellular radiotelephones (referred to as mobile stations or MSs) currently in use in America have a ten-digit mobile identification number ("MS number") that includes a three-digit area code ("MIN2") and a local number of seven digits ("MIN1"). Each ten-digit MS number can be duplicated in the US, Brazil, Argentina, Chile and other countries in the Americas. In wireline telephone systems, telephone numbers in each country also include a country code that is unique to each country and that is appended to the wired telephone number. Cellular radiotelephone systems have adopted a similar numbering plan by attaching five digits consisting of a mobile country code ("MCC") and a mobile network code ("MNC") for the ten-digit MS number. Accordingly, for purposes of international identification of the mobile station ("IMSI"), each MS has an international MS number consisting of an MCC, MNC, MIN2 and MIN1. However, existing American-type cellular systems have been designed to use only MIN2 and MIN1. As a result, an IMSI MS from Argentina is not allowed to operate in the US since it will most likely have the same MIN2 and MIN1 as a previous MS in the US. For example, the first word ("Word A") of an order message addressed to an MS contains the MIN1, the local MS number, and has no additional bits. As shown in Table 1 below, the MIN1 is a twenty-four-bit field included in Word 1 of a message.

Table 1 Word 1 - Address Word Abbreviated Since MIN1 can be identical for MSs with different MCCs, a page from a BS addressed to an IMSI MS could result in a false page to a - - previous MS with the same MIN1. In order to implement the IMSI in America in the new MSs, it is necessary to include the MCC and the MNC with each MS number to provide an IMSI MS number. Any solution to this problem must be compatible with the above in such a way that the previous MSs attending the control channel of the cellular radiotelephone system will not falsely interpret a page for an IMSI MS. One possibility is to add additional words to the pages sent by the cellular base stations ("BSs") to the MSs in the previous control channel. However, that solution is impractical since the capacity of the previous channel is wasted by the need to distribute the two additional IMSI messages for each page or order message, and the cellular radiotelephone systems in America are reaching capacity limits in some service areas due to the increasing number of new MSs that are added every day. Additional complications are encountered due to this solution in the reverse control channel that carries messages or commands from an IMSI MS to a BS. An additional word can not be accommodated in an origin from an MS. Also, the responses of an IMSI MS must not be interpreted through a BS of an earlier type that does not - - can accommodate the IMSI, and therefore a new type of message would be needed for each type of access message from an IMSI MS. However, there are not enough types of unassigned messages available in existing cellular radiotelephone systems in the Americas to accommodate them. For the above reasons, there is a need for a new IMSI process that is compatible with the above in cellular radiotelephone systems existing and that can be implemented without deterioration in the capacity of the cellular radiotelephone system. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a block diagram of an MS 100 that can advantageously utilize the IMSI process of the present invention. Figure 2 is a flowchart for the process used by the microprocessor 129 in Figure 1 to process both the IMSI and non-IMSI pages and the order messages from a BS. Description of the Preferred Modality Briefly described, the present invention comprises a signaling system for a radiotelephone system in a particular country where messages including at least a first word and a second word are communicated between the base stations and the mobile stations. Mobile station identification numbers that include at least one country code and a local number are assigned to each mobile station in a first group of mobile stations (mobile stations registered in a different country). Mobile station identification numbers including at least one local number are assigned to each mobile station of a second group of mobile stations (mobile stations registered in the country). Each of the messages comprises a first word that includes a local number for a message for a mobile station in the first group or in the second group or that includes a first predetermined encoded number for a message for a mobile station in the first group, the first word having a plurality of predetermined second coded numbers for encoding a local number of a mobile station in the first group or the second group, and without including the first predetermined coded number in the plurality of second predetermined coded numbers. A second word is appended to a message when the first word includes the first predetermined coded number, said second word including a plurality of third predetermined coded numbers for encoding a local number of a mobile station in the first group. The present invention also comprises a method - - for receiving the international identification of the mobile station in a radiotelephone system where messages including at least a first word and a second word are communicated between the base stations and the mobile stations. The first word of a message contains a predetermined encoded number or a coded local number. The second word of a message contains a local number if the first word contains the default encoded number. Each mobile station in a first group of mobile stations stores a mobile station identification number that includes at least one country code and a local number. Each mobile station of a second group of mobile stations stores a mobile station identification number that includes at least one local number. The method comprises the steps of: receiving a first word of a message; detect a local number in the first word, compare the detected local number with the stored local number, and process the message if the local number detected and the local number stored are the same; and detecting the predetermined coded number in the first word, receiving a second word of the message if the predetermined coded number is detected in the first word, detecting a local number in the second word, comparing the local number detected in the second received word with the local number - - stored, and process the message if the local number detected and the local number stored are the same. Referring to FIG. 1, a block diagram of an MS 100 is illustrated that can advantageously utilize the IMSI process of the present invention. In the preferred embodiment, the MS 100 is an AMPS type MS that is capable of operating on AMPS cellular radiotelephone systems in the US, Canada, Mexico and other countries of the Americas. The MS 100 can be used advantageously in any AMPS-type cellular radiotelephone system in the world that accommodates the IMSI according to the teachings of the present invention. The MS 100 includes a radio receiver 101 and a radio transmitter 103 coupled by a duplexer 107 to the antenna 105. The frequency of the radio channel to be used by the transmitter 103 and the receiver 401 is determined by the microprocessor 129 and transmitted to the frequency synthesizer. 103 through the interface circuit 113. The audio processing circuit 119 couples the audio signals from the receiver 101 to the speaker 131, and couples the audio signals from the microphone 132 to the transmitter 103. The messages to be transmitted by the transmitter 103 is encoded by microprocessor 129 and coupled to transmitter 103 via interface circuit 113. Messages received by receiver 401 are coupled through interface circuit 113 to microprocessor 129 for decoding. The interface circuit 113 may include suitable data coding and decoding circuitry, such as, for example, the Manchester data coding and decoding circuitry described in U.S. Patent No. 4,302,845, incorporated herein by reference. The interface circuitry 113 also controls the light emitting diodes 115 and 117, which are used to indicate the operational status of the MS 100. The microprocessor 129 is coupled to the ROM 121, EPROM 122, RAM 123 and EEPROM 124 memories for carry out the processing functions necessary for the MS 100 under the control of the programs stored in the ROM 121. The configurations characterizing the MS 100 are stored in the EEPROM 124 and include the MCC, MNC, MIN2 and MIN1, as well as as the system parameters for the cellular system. The MS 100 blocks can be implemented as described in U.S. Patent Nos. 5,029,233, 5,036,532 and 5,359,588, incorporated herein by reference. The MS 100 may also be any conventional cellular radiotelephone, such as, for example, the transceiver shown and described in the Motorola instruction manual number 68P81066E40, entitled "DYNATAC Cellular Mobile Telephone 800 MHZ Transceiver", published by and available from Motorola C & E Parts, 1313 East Algonquin Road, Schaumburg, Illinois 60196. In order to provide a solution compatible with the foregoing for the IMSI problem, according to the present invention, a unique code number MIN1 is used in the IMSIQ field to identify an IMSI access message from the IMSI MS or an order message from the IMSI from the IMSI BS. The unique code number MIN1 is selected so as not to be valid or unrecognizable (eg, not in a valid encoded s number range) for a previous MS or previous BS. As a result, a previous BS will treat an IMSI access message from an IMSI MS as invalid, and ignore it (for example, this situation can occur when the MSMS of the IMSI is accessing an IMSI BS and a previous BS of another system also receives the access message of the IMSI). Similarly, a command message of the IMSI from an IMSI BS will be ignored by a previous MS having the same MIN1 as the IMSI MS that is being paged. Referring to Table 2 below, the MIN1 of the IMSI message is shown, where, in the preferred embodiment, the thousands digit fields of the IMSI MS number are coded with an invalid code number. The thousands digits are a binary number in binary coded decimal format that has a range from 0001 to 1100 to represent the digits from 1 to 9, 0, * and In this way, the invalid code numbers are 0000, 1101, 1110 and 1111. By setting the thousands digits for the invalid code number of 0000, for example, all other MSs will ignore an order from a BS and only the MSs of IMSI will recognize it and decode the remaining words on the page. Accordingly, in the IMSI signaling system of the present invention, the thousands digits in the IMSIQ field will be set to the binary coded number 0000.

Table 2 Sample MS number of 523-3978 The 20 bits in the NXX and XXX fields of the IMSI signaling system are available for other signaling purposes with respect to the IMSI MSs. In alternative embodiments, the invalid coded numbers in the NXX and XXX fields each having a maximum value of 999, can be used to page the IMSI MSs. For a previous MS number that is 523-3978, the thousands digits are the binary number 0011 to represent 3. In addition to the unique code number MIN1 in the IMSIQ field, Word A is coded for the IMSI as shown below in the Table 3, and an additional word containing the MIN1 as shown below in Table 4 is included as the last word in accessing the IMSI from an IMSI MS or an IMSI command from an IMSI BS to transmit the MIN1. Note that Word A also includes fields for the MNC and MCC of the MS, and MIN2 of the MS is in Word B. In the IMSI signaling system of the present invention, an MS of IMSI recognizes a BS of IMSI upon detecting that an IMSI bit is set in the message stream of the upper part sent by the IMSI BS. The IMSI bit is not set in the message stream of the upper part by a previous BS. If the IMSI bit is set, then the IMSI MS accesses the IMSI BS with the unique code number MIN1 in the first word of the access message, an A Word of IMSI, and the last additional word established in the local number of MS. If the IMSI bit is not set, then the IMSI MS accesses the previous BS with the MIN1 in the first word of the access message set in the local MS number. The BS operates in a similar manner when it sends messages, such as commands and pages to a previous MS or an IMSI MS.

Table 3 IMSI Word A - Address Word Abbreviated - Table 4 LAST Word of IMSI Since the cellular system can now determine that an access from IMSI MS or an order from an IMSI BS is an IMSI access or an IMSI order, you can now know that an additional word will be sent even when the NAWC does not support that length. The suggestion is to simply add the additional word to the end of the message and have two last words in that case with NAWC = 0. For an Extended Protocol access the message length field will support the additional word. Referring next to Figure 2, a flow chart for the process used by the microprocessor 129 in Figure 1 is illustrated to process both the IMSI and non-IMSI pages and commands from a BS. The flow chart in Figure 2 can also be used in the BS to process both the non-IMSI access messages from a previous MS and the IMSI access messages from an IMSI MS. Upon entering block 202, MS 100 receives a control message such as an order or page from a BS. The process then proceeds to the decision block 204 where a check is made to determine if the MIN1 and MIN2 received in the message match the values stored in the memory of the MS. If they match, the SI branch of the decision block 204 is taken to the block 206 where the microprocessor 129 processes the command, and after this the process goes back to block 202 to wait for the next message. If the MIN1 and MIN2 received in the message do not match the values stored in the memory of the MS, the branch NO of the decision block 204 is taken to the decision block 208, where the microprocessor 129 checks to see if the digit thousand of MIN1 is coded with 0000 to indicate the IMSI. If not, the branch NO is taken to block 210 to ignore the command, and after this the process goes back to block 202 to wait for the next message. If the thousand digit of MIN1 in the IMSIQ field is coded with 0000 to indicate the IMSI, the SI branch of the decision block 208 is taken to block 212, where the microprocessor 129 processes the command as a - - Word A of IMSI, in search of MNC, MCC and IMSIQ instead of MIN1. Then, in the decision block 214, the microprocessor 129 checks to see if the MCC and the MNC received in the message match the values stored in the memory of the MS. If not, the branch NO is taken to block 216 to ignore the command, and after this the process goes back to block 202 to wait for the next message. If the MCC and the MNC received in the message match the values stored in the memory of the MS, the SI branch of the decision block 214 is taken to the decision block 218, where the microprocessor 129 processes the last additional word contained in the block. MIN1 Then, in the decision block 220, the microprocessor 129 checks to see if the MIN1 received in the message matches the value stored in the memory of the MS. If not, the NO branch is taken to block 222 to ignore the command, and after this the process goes back to block 202 to wait for the next message. If the MIN1 received in the message matches the value stored in the memory of the MS, the SI branch of the decision block 220 is taken to block 224, where the microprocessor 129 processes the command, and after this the process goes back to the block 202 to wait for the next message. In order to implement the system of - - IMSI signaling of the present invention in the Electronic Industries Associates Interim Standards IS-91 for AMPS type cellular systems, the following revisions to the IS-91 Standard are required. Copies of Standard IS-91 can be obtained from Electronic Industries Associates in Washington, D.C., USA. The sections of IS-91 that have been revised are underlined in the following description. 2.6.2.2 Page match The MS must monitor the MS control messages for the page messages (see 3.7.1.1). • If the ROAM status is disabled, the MS should try to match the MIN1P with the MINlr for the one-word messages and both the MIN1P and the MIN2P with the MINlr and the MIN2r, respectively, for the two-word messages. All decoded MIN bits must match to cause the MS to respond to the message. • If the ROAM status is enabled, the MS must try to match both the MIN1P and the MIN2P with the MINlr and the MIN2r, respectively. All decoded MIN bits must match to cause the MS to respond to the command.

When a match occurs, the MS must enter the System Access Work with a "page response" indication (see 2.6.3). If the IMSI bit is set, then the MS should try to decode the first word of the order message as an IMSI Word A. If a match occurs, the message must also decode the agreement of both the MIN1P and the MIN2P with the MINlr and the MIN2r, respectively. When a match occurs, the MS must enter the System Access Work with a "page response" indication (see 2.6.3). 2.6.2.3 Order The MS should monitor the control messages of the MS for the orders and should try to match both the MIN1P and the MIN2P with the MINlr and the MIN2r, respectively.

All decoded MIN bits must match to cause the MS to respond to the command. If the IMSI bit is set, then the MS should try to decode the first word of the order message as an IMSI Word A. If a match occurs, the message must also decode the agreement of both the MIN1P and the MIN2P with the MINlr and the MIN2r, respectively. All decoded MIN bits must match to cause the MS to respond to the order message. - lí The responses to the following order messages are: 2.6.3.7 Service demand The MS must continue sending its message to the BS. The information that must be sent is the following (with the formats given in 2.7.1): • Assume that the access is not an extended protocol message (see section 2.7.1.2 and Table 3.7.1.1-3). Then: If IMSI is established Then: WORD A of IMSI is sent. If not: WORD A is sent. Add the following near the bottom of 2.6.3.7: • If the access is an "origin" and IMSI is equal to 1, then the LAST word of IMSI is sent after the last digit word marked or the LAST word of IMSI N 'is sent if the access is an extended protocol access. • If the access is different to an "origin" and the IMSI is equal to 1, then the IMSI word is sent after the word with NAWC = 0 or the LAST IMSI word N 'is sent if the access is an access of extended protocol.

- Word A of IMSI - Address Word Abbreviated - Word A - Address Word Abbreviated Word B - Extended Address Word Word C - Serial Number Word C Word - Authentication Word Word C - Single Word of Confirmation of Order of Demand Word C - Demand Word for Base Station - Word D - First Word of the Address-Call - - Word E - Second Word of the Address-Call Word F - Third Word of the Address-Call - Word G - Fourth Word Address-Call ULTIMA Word of IMSI MNC Two Digits of Mobile Network Code coded as 10 * D2 + DI MCC Three Digits of Mobile Country Code coded as 100 * D3 + 10 * D2 + DI The IMSIQ Qualifier of IMSIQ is set for all at zero. This creates a combination of invalid MIN1 in the first word of an order that causes the order to be ignored by previous systems in marginal cell situations. 3.6.2.2 Page To page an MS, an MS control message should be sent (see 3.7.1.1). Local MSs can be paged with a one-word or two-word message. Vagrant MSs must be paged with a two-word message. In the case of a page with IMSI, a third word is sent with the MNC and the MCC. 3.6.2. Order Orders and order confirmations should be sent to the MSs with a two word MS control message (see 3.7.1.2). In the case of an order with IMSI, a third word is sent with the MNC and the MCC. The following orders can be transmitted to a MS operating in the free work unit: 3.7.1.1 Mobile Station Control Message The control message of the MS may consist of one to eight words.

Word 1 of IMSI - Address Word Abbreviated In the signaling system of the IMSI, the control message of the MS may consist of one to eight words.

Word 1 - Address Word Abbreviated Word 2 - Extended Address Word SCC = 11 SCC? Ll Word 2 '- Extended Protocol Word - - Word 3 - Initial Assignment of the Voice Channel to Low Power Word 3 - First Word of Extension - - Word 4 - Second Word of Extension Both the First Word of Extension and the Second Word of Extension must be sent if ORDER and ORDQ indicate Extension Number Information.

Word 3 '- Word of Assignment of the Narrow Analogue Channel of Extended Protocol (for MST = 10000000) Word 3 - First Word of Directed Reinvention Word 4 - Second Word of Remanded Directed Word 3 - Order Confirmation Word of the Base Station Word 3 - Single Word of Demand Order Word 3 - First Word of Order of Update SSD Word 4 - Second Word of Order of Update SSD Word 5 - Third Word of Order of Update SSD Last Word of IMSI MNC Two Digits of Mobile Network Code coded as 10 * D2 + DI MCC Three Digits of Mobile Country Code encoded as 100 * D3 + 10 * D2 + DI The next bit of IMSI is sent out periodically on the control channel to indicate that the IMSI is maintained in this system.

- - Global Action Record Increase Message IMSI When the established indicates that the MS that contains the IMSI must respond with the word IMSI in the responses to the order. In summary, a single coded number is used MIN1 for identifying an IMSI access from an IMSI MS or an IMSI command from an IMSI BS, thereby providing an IMSI capability that is compatible with the above in terms of existing cellular systems and that can be implemented without deterioration of cellular system capacity.

Claims (6)

1. NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and therefore the property described in the following claims is claimed as property. A signaling system for a radiotelephone system where messages including at least one first word and a second word are communicated between the base stations and the mobile stations, with each mobile station assigned a mobile station identification number (100) which includes at least one country code (MCC) and a local number (MIN2, MIN1), said messages are each characterized by: a first word (Table 3) that includes a local number for a message or a first predetermined code number , the first word has a plurality of predetermined second coded numbers for encoding a local number for a mobile station, and without including the first predetermined coded number in the plurality of second predetermined coded numbers; and a second word (Table 4) appended to a message when the first word includes the first predetermined coded number, said second word includes a plurality of third predetermined coded numbers for encoding a local number for a mobile station.
2. 2. A signaling system for a system - - radiotelephone where messages including at least a first word and a second word are communicated between the base stations and the mobile stations, with each mobile station (100) of a first group of the mobile stations being assigned mobile station identification numbers including at least one country code (MCC) and a local number (MIN2, MIN1), and each mobile station (100) of a second group of mobile stations being assigned mobile station identification numbers that include at least one local number ( MIN2, MIN1), said messages are each characterized by: a first word (Table 3) that includes a local number for a message for a mobile station in the first group or the second group or that includes a first predetermined encoded number for a message for a mobile station in the first group, the first word has a plurality of predetermined second coded numbers for encoding a local number of a mobile station in the first group or the second group, and without including the first predetermined encoded number in the plurality of second predetermined encoded numbers; and a second word (Table 4) appended to a message when the first word includes the first predetermined coded number, said second word includes a plurality of third predetermined coded numbers for encoding a local number - - of a mobile station in the first group.
3. 3. A method for receiving the international identification of the mobile station in a radiotelephone system where the messages including at least a first word and a second word are communicated between the base stations and the mobile stations, the first word of a message contains a predetermined coded number or a local number, the second word of a message contains a local number if the first word contains the predetermined coded number, each mobile station (100) stores a mobile station identification number that includes at least one country code (MCC) and a local number (MIN2, MIN1), said method is characterized by the steps of: receiving (202) a first word of a message; detecting (204) a local number in the first word, comparing the detected local number with the stored local number, and processing the message if the local number detected and the local number stored are the same; and detecting (208) the predetermined coded number in the first word, receiving a second word of the message if the predetermined coded number is detected in the first word, detecting a local number in the second word, comparing the local number detected in the second word received with the stored local number, and process the message if the local number detected and the local number - - stored are the same.
4. 4. A method for receiving the international identification of the mobile station in a radiotelephone system where the messages that include at least a first word and a second word are communicated between the base stations and the mobile stations, the first word of a message contains a predetermined coded number or a local number, the second word of a message contains a local number if the first word contains the predetermined coded number, each mobile station (100) stores a mobile station identification number that includes at least one country code (MCC) and a local number (MIN2, MIN1), said method is characterized by the steps of: receiving (202) a first word of a message; detecting (208) the predetermined coded number in the first word; receiving (212) a second word of the message if the predetermined coded number is detected in the first word; and detect (214) a local number in the second word, compare the local number detected in the second received word with the stored local number, and process the message if the local number detected and the local number stored are the same.
5. 5. A method to receive the international identification of the mobile station in a system - - radiotelephone where messages that include at least a first word and a second word are communicated between the base stations and the mobile stations, the first word of a message contains a predetermined encoded number or a coded local number, the second word of a message contains a local number if the first word contains the predetermined coded number, each mobile station (100) of a first group of mobile stations stores a mobile station identification number that includes at least one country code (MCC) and a local number (MIN2, MIN1), and each mobile station (100) of a second group of mobile stations stores a mobile station identification number that includes at least one local number (MIN2, MIN1), said method is characterized by the steps of : receiving (202) a first word of a message; detecting (204) a local number in the first word, comparing the detected local number with the stored local number, and processing the message if the local number detected and the local number stored are the same; and detecting (208) the predetermined coded number in the first word, receiving a second word of the message if the predetermined coded number is detected in the first word, detecting a local number in the second word, comparing the local number detected in the second word received with the stored local number, and process the message if the detected local number and the stored local number are the same. The method according to claim 5, further characterized by the step of: in each mobile station of the second mobile group, ignoring the message if a local number is not detected in the first word. METHOD OF INTERNATIONAL IDENTIFICATION OF MOBILE STATION AND SIGNALING SYSTEM FOR RADIOTELEPHONES AND CELLULAR SYSTEMS Summary of the Invention A cellular radiotelephone or MS (100) includes an international mobile station identification which includes a country code of the MCC mobile, a mobile network code MNC, an area code MIN2 and a local number MIN1 , all of which are stored in the EEPROM memory (124) of the MS. In the signaling system of the IMSI, a unique code number MIN1 is used in the IMSIQ field of access and order messages to identify an access message of the IMSI from an IMSI MS or an IMSI order message from from a base station of the IMSI or BS. When receiving the order messages, an IMSI MS looks first for its MIN1, and if it does not find it, it looks for the only code number MIN1 in the IMSIQ field. If the only code number MIN1 is detected, then the IMSI MS looks for the MIN1 in the last word of the message.