CA2134976A1 - Circuit for passing together sets of sequences of digits to form telephonic identification codes and method therefor - Google Patents

Abstract

A circuit and associated method for a radiotelephone which parses together sets of sequences of digits to form a telephonic identification code. Telephonic identification codes are stored in memory elements (506) and the present location of the telephonic apparatus is also stored in a memory element. A user of the radiotelephone desiring to effectuate a communication link with other telephonic apparatus inputs to the circuit portions of a telephonic identification code associated with the other telephonic apparatus. The circuit compares (518) the portion input by the user with stored telephonic identification codes. A stored telephonic identification code having similar digits is identified, and a new telephonic identification code is parsed together (524), if necessary, from the stored telephonic identification code based upon the present location of the radiotelephone.

Description

~: j wo 94122260 213 ~ 9 7 6 rcT/us94/0l849 CIRCUI~ FOR PARSING Tt:)GETHER SETS OF SEQUENCES-OF-DIGITS TO FORM
TELEPHONIC IDENTIFICATION C:ODES AIYD METHOD THEREFOR

S
B~ck~Fou~ of ~he Inveption The present invention relates generally to circuitry for storing and retrieving telephonic identification codes and, more particularly, to a circuit operable with telephonic apparatus, such as a radiotelephone, for parsing together sets of sequences of digits, thereby to form a telephonic identifilcation code which, when transmitted to a telephone system, permits initiation of ef~ctuation of a communication link with telephonic apparatus associated with the telephonic identification code.
A communication system is comprised, at a minimum, of a transmitter and a receiver interconnected by a transmission channel. A communication signal generated by the transmitter is transmitted upon the transmission channel, thereafter to be received 2 0 by the receiver.
A two-way communication system is a communication system which permits both transmission and reception of communication sig~ials between at least two locations. Two-way communication between the at least two locations is thereby permitted.
2 5 A telephonic communication system and a radio communication system are types o~ two-way communication systems. A telephonic commu~ication system, hereinafter referred to by the te~m telephone system, includes a f~ed infrastructure to which conventional telephonic apparatus is electrically connected.

3 0 The locations at which the conventional telephonic apparatus are connected to the fixed infrastructure are uniquely identified by a ,``
code. ~.
To transmit communication signals between selected telephonic apparatus connected to the telephone system, a 3 5 communication link mus~ first be ef~ectuated between the selected WO 94/22260 213 4 9 7 ~ PCT/~S94/01849 -- ~

telephonic apparatus. Hereina~er, the telephonic apparatus between which communication links are ef~ectuated shall be referred to as origination telephones and destination telephones. (As the destination telephone is usually positioned remote from the S orig~nation teleph~ne, the term "remotely-positioned tclephone" shall also at times be utilized with reference to the destination telephone.) A user desiring to effectuate the communication link prov~des a code, by way of the orig~nation telephone to the fixed infrastructure of the telephone system, which uniquely identifies the destination I O telephone. Operation of the fixed infrastructure permits effectuation of the communication link between the origination and destination t lephones, thereby forming the transmission channel which permits communication signals to be transmitted between the or~gination and destination telephones. Such effectuation of the 15 communication link which permits transmission of communication signals between the origination and destination telephones shall hereinafter, at times, be referred to by the term "telephone call" or "call."
The code which uniquely identifies the location at which 2 0 telephonic apparatus is connected to the telephone system is comprised of 8 sequence of digits, generically referred to as a "telephone number." As the number of digits required to identify a destinatior. telephone connected at a particular location to the f~ed infrastructure of the telephone system is dependent upon the relative 2 5 positions of the origination and destination telephones, the term telephonic identification code shall be used to identify such unique code. The telephonic identification code includes at least a portion of a primaly telephone number, and, in some instances, also one or more sets of ~equences of prefi2~ digits concatenated to the at least 3 0 portion of the telephonic identification code.
A radio communication system, briefly noted hereinabove as a type of two-way communication system, is a communication system, ``
as abov~defined, but wherein the transmission channel comprises a radio frequency channel. The radio frequency channel is defined by a 3 5 range of frequencies of the electromagnetic frequency spectrum. A

wos4/~260 2134976 PCT/11594/018J9 transmitter operative in a radio communication system converts a communication signal which is to be transmitted into a form suitable for transmission thereof upon the radio frequency channel.
Conversion of the communication signal into the form suitable t~
5 for the transmission thereof upon the radio frequency channel is ef~ectuated by a process referred to as modulation. In such a process, the communication signal is impressed upon an electromagnetic wave. The electromagneGic wave is commonly referred to as a "carrier sign~l." The resultant signal, once modulated by the 10 communication signal, is referred to as a modulated carrier signal, or, more simply, a modulated signal. The transmitter includes circuitry operative to perform such a modulation process.
Because the modulated signal may be transmitted through free space over large distances without the requirement of a f~ed I S connection between the transmitter and the receiver operative in such a radio communication system, radio communication systems are oftentimes utilized to effectuate communication between a transmitter and a remotely positioned receiver.
The receiver of a radio communication sy~tem which receives 2 O the modulated carrier signal contains circuit~y analogous to, but operative in a manner reverse with that of, the circuitry of the transmitter and is operative to perform a process referred to as demodulation .
A radio transceiver is a device which includes both a radio 2 5 transmitter and a radio receiver to permit thereby two-way communication therethrough.
Improvements in radio telephony techniques and apparatus, have permitted the formation of cellular communication systems. A
cellular communication system is a type of radio communication 3 O system. Radio transceivers are utilized in a cellular communication system thereby to permit two-way communication.
A cellular communication system permits two-way communication by way of a radio transceiver positioned at any locatio~ within a geographic area encompassed by the cellular 3 5 communication system.

WO 94/22260 2 1 3 ~ 9 7 6 PCT/11594/01849 ~

A cellular communication system is created by positioning a plurality of f~ed-site radio transceivers, referred to as base stations, at spaced-apart locations throughout a geographic area. The base stations are connected to a conventional telephonic system.
S Associated with each base station of the plurality of base statior,s is a portion of the geographic are~ encompassed by the cellular communication system. Such portions are referred to as cells. Each of the plurality of cells is defined by one of the base stations of the plurality of base statioIls, and the plurality of cells together define the 10 coverage area of the cellular communication system.
A radio transceiver, referred to in a cellular communication system as a cellular radiotelephone or, more simply, a cellular phone, positioned at any location within the coverage area of the cellular communication system, is able to communicate through the 1 5 can~entional telephonic system by way of a base station. Modulated signals generated by the radiotelephone are transmitted to a base station, and modulated signals generated by the base station are transmitted to the radiotelephone, thereby to effectuate two-way communication therebetween. (A sigIlal received by a b~se station is 2 0 then transmitted to a desired location of the conventional telephonic system by conventional telephony techniques. And, signals generated by conventional telephonic apparatus of the conventional telephonic system are transmitted to a base station by conventional telephony techniques, thereafter to be transmitted to the 2 5 radiotelephone by the base station.) The radiotelephones operative in the cellular communication system are constructed to be operative in manners corresponding as closely as possible to the manner is which telephonic apparatus , which fo~n the or~gination and destination telephones connected to a 3 0 telephone system as above-described is operative and, hence, are analogous in operation with operation of such telephones. r' As cellular communication systems are integrated with conventional telephone systems (by way of the aforementioned base stations) and the cellular communication system and the 3 S conventional telephone system together appear to the user to be a W094/~2260 213~ PC~'IU594101849 1 ~

single communication system, the term telephone system shall hereinafter refer not only to the conventional telephone system but ~ -also to a cellular communication system integrate~ therewith. Also, a radiotelephone operational in a cellular communication system S shall hereina~ter also be referred to as a telephone (and also, when appropriate, as an origination or destination telephone).
As mentioned briefly hereinabove, when a user of an origination telephone desires to ef~ectuate a communication link with a destinatiorl telephone, a telephonic identification code, fo~med of a 10 unique sequence of digits and associated with the location at which the destination telephone is connected to the telephone system, is provided to the fixed infrastructure. The telephone 6ystem interprets the telephonic identification code and thereafter permits ef~ectuation of the communication link with the destination telephone located at 15 the position associated with the telephonic identification code.
A user of a cellular phone forming the origination telephone similarly desiring to ef~ectuate a communication link with a destination telephone enters a unique sequence of digits into the cellular phone. Circuitry of the cellular phone (including circuitry 2 0 which performs the aforementioned modulation process) causes the telephonic identification code to be transmitted to a base station -which is connected to the fi~ed infrastructure of the telephone system. The telephone system thereafter permits effectuation of the communication link with the destination telephone. Hence, a user of 2 5 a cellular phone comprising an origination telephone initiates a communication link with a destination telephone in the same manner in which a communication link is effectuated by a user of i-conventional telephonic apparatus. ~-As also noted previously, the number of digits comprising the 3 0 telephonic identification code is dependent upon the relative locations of the telephones between which the communication link is to be ~ ~`
effectuated.
For instance, many telephone systems are defined by a A` 'plurality of zones. When a communication link is to be ef~ectuated 3 5 between origination and destination telephones which are both _ , ,~ ,, , , , ",, " ,. . . . .. . .... . . .

WO 94/2226û 213 49~ 6 PCT/I~S94/01849 ~

positioned within a single zone, some telephone systems require only a first set of digits forming a primary telephone number ~o comprise the telephonic identification code to permit the ef~ectuation of the communication link between the origination and destination 5 tPlephones. Such a call resulting therefrom shal!, at times, hereinafter be referred to as an "intrazonal" call.
When a communication link is to be ef~ectuated between origination and destination telephones which are positioned in different zones, one or more sets of prefix dig~ts are required to be 1 0 concatenated to at least a portion of the pr~mary telephone number to permit the ef~ectuation of the communication link between the origination and destination telephones. Such call resulting therefrom shall, at times, hereinafter be referred to by the term "interzonal call." In the United States, such set of pref~ digits is 15 commonly referred to as the area code.
When a communication link is to be ef~ectuated between orig~nation and destination telephones located in dif~erent telephone systems, sets of prefi2~ digits are also required to be concatenated to the at least portion of the primaIy telephone number to permit the 2 0 effectuation of the communication link between the origination and destination telephones positioned in the different telephone systems.
Such a call resulting therefrom shall, at times, hereinafter be referred to as an "intersystem" or "suprasystem" call. As telephone systems are typically formed to e~tend along national, geographic 2 5 boundaries, dif~erent nations have different telephone systems and an intersystem call is typically a call between telephones positioned in two different nations. Such a call is also oftentimes referred to as an international call. In an international call, a first set of prefix digi+s, referred to as an international access code, and also a second 3 0 set of prefi~ digits, referred to as a country code, are both concatenated to at least a portion of a primary telephone number such that the sets of pref~ digits and the at least portion of the primary telephone number together form a telephonic identification code permitting a communication link to be effectuated between the WO 94/~260 7 PCT/U594/01849 :.i, origination and destination telephones positioned in the two dif~erent telephone systems.
When the origination and destination telephones between which the communication link is to be ef~ectuated are fi~edly 5 connected to a conventional telephonic system, the locations at which such telephones are positioned dc not vary. Therefore, a user of an origination telephone positioned at a first, particular location, always dials, or otherwise enters, the same telephonic identification code when a communication link is desired to be effectuated with a i O destination telephone positioned at a second, particular position.
As many telephones include memory devices to permit dialing of pre-stored ~equences of digits forming telephonic identification codes upon actuation of only a single key (or several keys), the sequences of digits required to be dialed, or otherwise entered, 1 5 through the destination telephone to initiate effectuation of a communication link with a destination telephone may be stored in the memory device of the origination telephone. The memorv devices thereby facilitate dialing, or other entry, of the required sequences forming the telephonic identification codes to initiate effectuation of 2 0 the communication link with the destination telephone.
However, when the origin~tion telephone is comprised of a radiotelephone, such as a cellular phone utilized in a cellular communication system, the radiotelephane is not maintained in a f~ed connection with a telephone system. A radiotelephone may be 2 5 positioned, at different times, in dif~erent zones of a single telephone system or be positioned, at different times, in different telephone systems. As the sequences of digits which form the telephonic i.
identification code required to be entered to initiate effectuation of a communication link by an origination telephone with a destination 3 0 telephone is dependent upon the relative positions of such telephones, the telephonic identification code required to be entered through a radiotelephone comprising the origination telephone varies depending upon the different locations at which the radiotelephone is positioned. Because of such variance in the sequences of digits 3 5 forming the telephonic identification code required to initiate wo 94/22260 213 4 g 7 G PCT/US94/01849 ' ``

ef~ectuation of a communication link, use of conventional memor~
devices which store sequences of digits fo~ning the telephonic identification codes is of little bene~lt as an unworkably large number of dif~erent telephonic identification codes would have to be stored to S identify any particular destination telephone.
What is needed, therefore, is an improved apparatus and method for telephonic apparatus which overcomes the limitations of the e~isting art.

1 0 ~umIrLar-! of ~ç Invention The present invention, accordingly, provides an apparatus and associated method which overcomes the limitations of the e:~istimg art.
i 5 The present invention further advantageously provides a circuit for telephonic apparatus for parsing together sets of sequences of digits to form thereby a telephonic identification code.
The present invention further advantageously provides a radio transceiver incorporating such circuitry for parsing together sets of 2 0 sequences of digits to form a telephonic identification code.
The present invention yet further advantageously provides a method for parsing together sets of sequences of dig~ts to form thereby a telephonic identification code.
The present invention includes further advantages and 2 5 features, the details of which will become more readily apparent upon reading the detailed description of the preferred embodiments hereinbelow.
In accordance with the present invention, therefore, a circuit operable with telephonic apparatus is disclosed. The circuit fo~ns a 3 O telephonic identification code of which a primary telephone number forms at least a portion and which, when transmitted to a telephone - system, permits initiation of effectuation of a communication link with destination telephonic apparatus associated with the telephonic identification code. A first set of sequences of digits which ~orm at 3 5 least the portions of telephonic identification codes which comprise WO 94/22260 PCT/US94101849 if '' 213 4 ~ i7! 6~ ~ r primary telephone numbers is stored. A second set of sequences of dig~ts which form prefix digits of telephonic identification codes is also stored. At least part of a known portion of a primary telephone number of a selected, destination telephonic apparatus is compared with corresponding parts of the first set of sequences of digits. A
primary telephone number stored therein is identified which corresponds with the at least part of the known portion of the prima~y telephone number. And the telephonic identification code which pelmits initiation of the effectuation of the communication link with the selected, destination telephonic apparatus is parsed together wherein at least a portion of the telephonic identification code parsed-together thereby is formed of at least a portion of the prim~Iy telephone number identified as a result of comparisons between the known portion of the primaly telephone number and the first set of 1 5 sequences of dig~ts.

Brief~escri~tion ofthe DrawinF~

The present invention will be better understood when read in 2 0 light of the accompanying drawings in which: -FIG. 1 is a representation illustrating intrazonal, interzonal, and intrasystem calls formed as the result of effectuation of communication links between two remotely positioned telephones;
FIG. 2 is an illustration of a telephonic identification code 2 5 formed of a primary telephone number and sequences of pref~
digits;
FIG. 3 is a chart listing the telephonic identification codes required to identify a destinatlon telephone to effectuate a communication link between an origination telephone and the 3 0 destination telephone when the originatioIl telephone is positioned at various locations;
FIG. 4 is a chart, similar to that of FIG. 3, which lists further e2camples of the telephonic identification codes required to effectuate a communication link between an origination telephone and the WO 94/22260 PCT/US94/01X49 ` `.
213 197i~ :

destination telephone when the orig~nation telephone is positioned at various locations; .
FIG. 5 is a chart, similar to those of FIGS. 3 and 4, which lists further examples of the telephonic identification codes required to.
S identify a destination telephone to ef~ectuate a communication link between an origination telephone and the destination telephone when the origination telephnne is positioned at various locations;
FIG. 6 is another chart, similar to those of FIGS. 3-5, which lists still further examples of the telephonic identification codes 1 0 required to identify a destination telephone to effectuate a communication link between an origination telephone and the destination telephone when the origination telephone is positioned at various locations;
FIG. 7 is a functional block diagrarn of the circuit of a 1 5 preferred embodiment of the present invention and of a radio transceiver including such circuit;
FIG. 8 is a logical flow diagram listing the method steps of the method of a preferred embodiment of the present invention;
FIG. 9 is a flow diagram illustrating an algorithm utilized 2 0 during operation of a preferred embodiment of the present invention;
and FIG. 10 is a flow diagram illustrating another algor~thm also utilized during operation .of the preferred embodiment of the present invention.
pescril)tion of thQPreferre~ Emb~irnents Turning first to the illustration of FIG. 1, two separate telephone systems, represented by circles and referred to by reference 3 0 numerals 10 and 14 are shown. First telephone system 10 is comprised of a plurality of zones, here Zones 1, 2, 3, 4, . . . and N
wherein each Zone 1-N of first telephone system 10 compFises a portion of the telephone system 10. Similarly, second telephone system 14 is also comprised of a plurality of zones, again Zones 1, 2, 3, WO 94/Z2~60 2 ~ 3 ~ 9 ~ G ~ PCT I S94/1) 1849 1 `~

]
. . . and N wherein each Zone 1-N comprises a portion of the second telephone system 14.
An origination telephone positioned within any Zone 1-N of either first telephone system 10 or second telephone system 14 may. 5 S initiate ef~ectuation of a communication link with a destination telephone positinned in any Zone 1-N of ~ither first telephone system 10 or second telephone system 14. (While, for purposes of illustration, only first and second telephone systems 10 and 14 are shown, additional t~lephone systems may be similarly illustrated~ and communication links may similarly be ef~ectuated with telephones positioned therein.) Point 22 located in Zone N of first telephone system 10 of FIG. 1 is representative of a telephone positioned within Zone N of first telephone system 10. Point 28 is also representative of a telephone 1 5 positioned within Zone N of first telephone system 10. First line 34 interconnecting points 22 and 28 is repre~entative of a communication link ef~ectuated between two te,ephones (represented by points 22 and 28) positioned within Zone N. In this example, the telephone represented by point 22 comprises a destination telephone 2 0 and the telephone represented by point 28 comprises an origination telephone.
Point 38 shown in Zone 2 of first telephone system 10 is representative of a telephone positioned within Zone 2 of the first telephone system 10. And, second line 44 interconnecting points 22 2 5 and 38 is representative of a communication link effectuated between the two telephones (represented by points 22 and 38) positioned in Zones 2 and N of first telephone system 10.
Similarly, point 50 shown in Zone 3 of second telephone system `~
14 is representative of à telephone positioned within Zone 3 of the 3 0 second telephone system 14. And, line 56 interconnecting points 22 and 50 is representative of a communication link effectuated between i~
the two telephones (represented by points 22 and 50) positioned in ~' Zones N and 3 of telephone systems 10 and 14, respectively.
Line 34 interconnecting points 22 and 28 is also representative 3 5 of a intrazonal call; second line 44 interconnecting points 22 and 38 is W094/2~60 213~976 PCI'IU594/01849 also representative of an interzonal call; and, line 56 interconnecting points 22 and 50 is also representative of an intersystem call.
As an e:~ample, if the telephone repr~sented by point 28 forms an origination telephone and the telephone represented by point 22 5 represents a destination telephone, ef~ectuation of a communication link between the destination and origination telephones is initiated when a user of the origination telephone enters a telephonic identification code which identifies the destination telephone.
Analogously, when telephones represented by points 38 and 50 1 0 alternately form origination telephones, and the telephone repr~sented by point 2~ aga~n compr~ses a destination telephone, ef~ctuation of communication links between such origination and destination telephones is analogously initiated by entering telephonic identification codes which identify the destination telephone.
l S However, the telephonic identification codes required to initiate the ef~ectuation of the communication links with the destination telephone represented by point 22 vary depending upon the location of the originatiorl telephone. While the telephonic identification codes required to identi~y the destination telephone all include at least 2 0 portions of the primary telephone number associated with the destination telephone, when the origination telephone is positioned beyond the zone in which the destination telephone is positioned, additional sequences of prefi~ digits are required to be concatenated to the at least portion of the primary telephone number to identify 2 ~ properly the destination telephone.
FIG. 2 is an illustration of a telephonic identification code, referred to generally by reference numeral 100. Telephonic identification code 100 is representative of a typical telephonic identification code formed of a primary telephone number 106 having 3 0 sequences of pref~ digits 112 and 118 concatenated thereto. A
telephonic identification code is uniquely associated with a particular telephone, such as the telephone represented by point 22 in FIG. 1.
The length of the telephonic identification code is, however, dependent upon the relative location of the telephones between which 3 S the communication link is to be effectuated.

WO 94/2Z260 2 13 4 9 7 6 ~ PCT/U594/01849 - l3 -The relatiYe locations of the origination and destination telephones between which a communication link is to be ef~ectuated is determinative of the length of the telephonic identification code required to effectuate the communication link. More particularly, S sequences of prefix digits are concatenated to the primary telephone number when an interzonal or intersystem call is made, but such sequences of digits are not r quired when an intrazonal call is made.
In some telephone systems, such as the telephone systems of several of the Nordic countries and as shall be noted in more detail with 1 0 respect to the specific examples noted therein, a left-most digit (referred to in such countries as a domestic dialing code) of the primary telephone number is truncated and the sequences of prefix digits are thereafter concatenated to the remaining portion of the primary telephone number.
1 5 The sequences of pref~ digits 112 and 118 are representative of a country code and an international access code, respectively, which form portions of a telephonic identification code when an intersystem call is to be made.
FIG. 3 is a chart listing e~:amples of telephonic identification 2 0 codes required to identify a destination telephone, thereby to effectuate a communication link with a destination telephone from an origination telephone located at various positions. The locations at which the origination telephones are positioned are shown at the left-hand side of the chart and the telephonic identification code 2 5 required to identify a destination telephone located at a single position is shown at the right-hand side of the chart. The location of the destination telephone, in the e~amples of the chart of FIG. 3 is, in each instance, Chicago, Illinois, USA. With reference to the illustration of FIG. 1, the destination telephone may be considered to 3 0 be the telephone represented by point 22. When the origination telephone is also located at Chicago, Illinois, USA, a communication link effectuated between the two telephones is representative of an intrazonal call and, with reference still to FIG. 1, may be represented by line 34 e2ctending between points 28 and 22. The telephonic 3 5 identification code required to identify the destination telephone to WO 94/22260 213 4 9 7 6 PCT/11594101849 ~:

1~
ef~ectuate the communication link between such two telephones is comprised only of a portion of a primary telephone number, here a sequence of seven digits (555-2233).
In the second example of the chart of FIG. 3, the destination S telephone is again located at Chicago, Illinois, USA and again may be considered to be a telephone represented by point 22 of FIG. 1. The origination telephone is located, in this second example, at New York, New York, IJSA and may be considered to be the telephone represented by point 38 of FIG. 1. The telephonic identification code I O required to identify the destination telephone to ef~ectuate a communication link between the two telephones is a primary telephone number formed of a sequence of seven digits (555-2233) together with a sequence of prefix digits (312). (In the United States, the first three dig~ts of the primary telephone number is referred to l 5 as an "area code.") In the third example of the char~ of FIG. 3, the destination telephone is once again located at Chicago, Illinois~ USA, and may again be considered to be the telephone represented by point 22 of FIG. 1. The oIigination telephone is located at Stockholm, Sweden, 2 0 and may be considered to be the telephone represented by point 50 of FIG. 1. The telephonic identification code required to identify the destination telephone to effectuate a communication link between the two telephones requires sequences of prefi~c digits additional to the area code (312) to be concatenated to the prima~ telephone number 2 5 (shown in the preceding two eacamples to be 555-2233). An international access code (009), identified by reference numeral 118 of telephonic identification code 100 of FIG. 2 and a count~y code (1), identified by reference numeral 112 of identification code 100 of FIG.
2, are concatenated to the primary telephone number.
3 0 Hence, the three examples of FIG. 3 illustrate the variance of the telephonic identification code required to be dialed or otherwise entered to effectuate a communication link between the origination and destination telephones depending upon the relative locations of the telephones.

r~r . . : , - .

I.` ~
WO 94/22260 2~13 19 7 6 PCT/US94/01849 3 i .

FIG. 4 is a chart, similar to that of the chart of FIG. 3, but which illustrates further e2~amples of telephonic identification codes required to identify a destination telephone, thereby to ef~ectuate a c communication link with a destination telephone from an S origination telephone located at various positions. Here, the destination phone is located at a position in Stockholm, Sweden and, with reference to FIG. 1, can be considered ~analogous to the destination telephone of the examples of FIG. 3) to be the telephone represented ~y point 22 of FIG. 1. The or~gination telephone, in this example, is also located at a position in Stockholm, Sweden. The telephonic identification code required to identify the destination telephone to effectuate a communication link between the two telephones is shown, at the right-hand ~ide of the chart, to be formed of a sequence of nine digits (08-1234567).
1 5 In the second example of the chart of FIG. 4, the destination telephone is again located at a position in Stockholm, Sweden, but the origination telephone is located at a position in Copenhagen, I:)enmark. The telephonic identification code, shown at the right-hand side portion of the chart (009-46-8-1234567), includes both a 2 0 portion of a primary telephone number (8-1234567) and also sequences of prefix digits (009 and 46) concatenated thereto. Again, the sequences of digits concatenated to the portion of the pr~mary telephone number includes both an international access code (009) and also a country code (46). It should further be noted th~t the left-2 5 most digit of the telephonic identification code formed of the primary telephone number of the first e3~ample of FIG. 4 (namely, the numeral "0" is truncated from the primary telephone number) is also truncated. Such left~most digit, as noted hereinabove, is referred to as a domestic dialing code in the Nordic countries. The domestic 3 0 dialing code forms a portion of a telephonic identification code only ~:
when an intrasystem call is made and is not utilized when an intersystem call is made.
FIG. 5 is a chart, similar to the charts of FIGS. 3 and 4 which lists further examples of telephonic identification code~ required to 3 5 identify a destination telephone, thereby to effectuate a WO 94/~2260 213 ~ 9 7 6 PCT/US94/01849 . ~ `

communication link between the destination telephone and an origination telephone. Again, the destination telephone is located at a position in Stockholm, Sweden and may again be considered to be the telephone represented by point 22 of FIG. 1. The origination S telephone is located at a position in Copenhagen, Denmark and may be considered to be the telephone represented by point 50 of FIG. 1.
Because a communication link formed between such two locations comprises an intersystem call, the telephonic identification code (009-46-8-1234567), shown at the right-hand side portion of the chart, is 1 0 formed of both a portion of a primary telephone number (8-1234~67) and also sequences of prefix digits (009 and 46) concatenated thereto.
Again, the sequences of prefix digits include an international access code (009) and a country code (46), and it is again noted that the telephonic identification code does not include a domestic dialing 1 5 code, referred to previously with respect to the e~amples listed in the chart of FIG. 4. (That is, the domestic dialing code is truncated from t;he primary telephone number during formation of the telephonic identification code.) In the second example of the chart of FIG. 5, the destination 2 0 telephone is again located at a positian in Stockholm, Sweden and may again be considered to be a telephone represented by point 22 of FIG. 1. The origination telephone, in the e~ample, is also located at a position in Stockholm, Sweden. The telephonic identification code (010-1234~67~ required to identify the destination telephone to 2 5 effec~uate a communication link between the two telephones is shown at the right-hand side portion of the chart. The telephonic identification code is formed of a primary telephone number (Q10-1234~67) inçluding, as a left-most digit thereof, a domestic dialing code (of a value of " 0"). Again, the domestic dialing code is required 3 0 to fo~n a portion of a telephonic identification code when an intrasystem call is made.
FIG. 6 is a chart, also similar to the charts of the preceding figures, which lists further examples of telephonic identification codes required to identify a destination telephone, thereby to 3 5 effectuate a communication link between the destination telephone WO 94/22~60 21 ~ O .7 6 PCTIUS94/01849 and an origination telephone. In the first e:~ample of the chart of FIG. 6, the destination telephone is located at a position in Copenhagen, Denmark and may be considered, for purposes of .
illustration, to be the telephone represented by point 22 of FIG. 1. The S origination telephone is located at a position in Stockholm, ~weden and may be considered to be the telephone represented by point 50 of FIG. 1. The telephonic identifilcation code (009-45-30123456) required to form a communication link between the two telephones is shown at the right-hand side of the chart. In addition to the primary telephone 1 0 number (30123456), sequences of prefix digits (009 and 45) are concatenated to the primary telephone number and together form the telephonic identification code. Again, an international access code (009) and a country code (453 comprise the sequences of prefi~ digits concatenated to the prima~y telephone number.
1 5 In the second e~ample of the chart of FIG. 6, the destination telephone is again Copenhagen, Denmark which may again be considered to be the telephone represented by point 60 of FIG. 1. The orig~nation telephone is located at a position in Oslo, No~way. The telephonic identification code (095-45 30123456) required to effectuate 2 0 the communication link between the two telephones is shown at the right-hand side portion of the chart. The telephonic identification code is formed of a primaIy telephone number (30123456) and also sequences of prefix digits (095 and 45) concatenated thereto. Again, the sequences of prefix digits comprise an international access code 2 5 (095) and a country code (45). The two e~amples of the chart of FIG. 6 differ only in that the values of the international access code forming one of the sequences of digits concatenated to the primary telephone number differ corresponding to the position of the origination telephone.
3 0 While portions of the prim~ry telephone numbers for any .
destination telephone listed in any of the preceding e~camples are identical irrespective of the position of the origination telephone, sequences of prefix digits and the values thereof, may have to be concatenated to the portion of the primary telephone number 3 5 depending upon the location of the position of the origination WO 94/22260 ~13 4 9 7 6 PCT/US94/01849 telephone. And, a left-most portion of the prim~ry telephone number may also need to be concatenated or, conversely, truncated, from t~he primary telephone number depending upon the location of the position of the origination telephone~
S When the origination telephone comprises a radio transceiver, such as a cellular phone utilized in a cellular communication system, a communication link may be ef~ectuated when the radio transceiver is positioned at any of many varied locations including, for example, the locations of each of the positions of the origination I O telephones of the examples of the charts of FIGS. 3-6 described hereinabove. Storing each of the telephonic identification codes required to effectuate a communication link between the radio transceiver and telephonic apparatus comprising any destination telephone is impractical as the telephonic identification code required 1 5 to be dialed or otherwi3e entered to identify the destination telephone is dependent upon the location at which the radio tr~n~ceiver (forming the orig~nation telephone) is positioned. However, because at least a portion of the prima~y telephone number of the destination telephone forms a portion of the telephonic identification code 2 0 required to be dialed or otherwise entered to ef~ectuate a communication link, the telephonic identification code may be parsed together (viz., pieced together) to permit effectuation of the communication link between an origination telephone and a destination telephone.
2 5 Turning ne~ct to the block diagram of FIG. 7, a radiotelephone, referred to generally by reference numeral 300, is shown.
Radiotelephone 300 includes circuit 318 of a preferred embodiment of the present invention and is comprised of elements contained within the block shown in hatch. Radiotelephone 300 is operable both to 3 0 transmit and to receive modulated signals in a cellular communi~ation system as described hereinabove. Circuit 318 is operative to store telephonic identification codes pe~mitting parsing J
apart of the stored telephonic identification codes and thereafter parsing together component portions of the stored telephonic 3 5 identification codes to form a desired telephonic identification code WO 94/~21;0 2 1 3 4 9 7 6 PCT/IJ594/01849 which permits initiation of ef~ectuation of a communication link with other telephonic apparatus. When radiotelephone 300 comprises an origination telephone, circuit 318 is operational to form a desired telephonic identification code to permit initiation of ef~ectuation of ~ i S communicatiQn link with a destination telephone.
Circuit 318, shown in the illustration of the preferred embodiment of FIG. 7, includes processing dev~ce 324, here preferably a microprocessor, a memory element, here shown to be formed of stack memory 330, repertoly memo~ 336, and location 1 0 memory 342. Processing device 324 is connected to each of the memories 330-342 to permit the processing device 324 to write data to the memories 330-342 and to retrieve data therefrom.
Interface apparatus, here keypad input 348 and output display 354 are also shown in the figure. Input 348 and display 354 are also 1 5 appropriately coupled to processing dev~ce 324, thereby to permit input and output of data to and from processing device 324.
It should, of course, be understood that the elements of circuit 318 may be additionally utilized fior other functional operations of radiotelephone 300 in addition to the operational functionality of such 2 0 elements in circuit 318.
Transceiver circuitry 360 also forms a portion of radiotelephone 300 and is coupled to processing device 324 to permit thereby transfer of information therebetween.
Telephonic identification codes are stored in stack memory 330 2 5 and repertory memory 336. In the preferred embodiment of the present invention, stack and repertory memories 330 and 336 di~fer only in the manners in which the sequences of digits comprising telephonic identification codes stored in the respective memories are " , , ~
entered therein. A user of radiotelephone 300 stores in repertory 3 0 memory 336 a desired number of sequences of digits forming telephonic identification codes by entering the sequences of digits by ,~:
way of keypad input 348. Repertory memory 336 is, hence, analogous to the conventional memory device used to store freuqently dialed telephone numbers. Processing device 324 includes appropriate 3 5 control circuitry and/or algorithms to cause the sequences of digits WO 94122260 ~ 1 ~ 4 9 7 ~ PCT I 594/01849 1~' input through keypad input 348 into repertory memory 336. Such storage in reperto~y memoly 336 is analogous to storage of telephonic identification codes in conventional telephonic apparatus.
Stack memory 330 is operative to store telephonic identification codes associated with telephonic apparatus with which ef~ctuation of communication links are initiated by a user of radiotelephone 300 irrespective of whether such telephonic identification codes have been stored in repertory memory 336. Hence, stack memory 330 comprises a compilati~n of previously-dialed telephonic identification codes.
1 0 Processing device 324 in the preferred embodiment of the present invention is further operative to prevent redundant entries of the same telephonic identification code into stack memory 330.
A user of radiotelephone 300 also stores data pertaining to the location at which the radiotelephone is positioned in location memory 1 5 342 by inputting such data into location memory 342 by way of keypad input 348. Again, processirlg de~ice 324 is operable to write such data into memory location 342. When radiotelephone 300 is initially positioned in any zone of any telephone system, the user of the radiotelephone 300 inputs such initial location into location memory 2 0 342 by way of input keypad 348. As the radiotelephone 300 is relocated to be repositioned at other zones of the telephone system or within other telephone systems, the user of radiotelephone 300 again inputs data pertaining to such repositioning into location memory 342, thereby to update the location of the position of the radiotelephone.
2 5 The data stored in location memory 342 comprises data associated with international access codes and country codes utilized in the telephone systems.
Therefore, the infoFmation required to ~orm a telephonic identification code, formed of, at least in part, a primary telephone 3 0 number of a previously-stored telephonic identification code, is stored in the memories 330 and 336. And, because information pertaining to the present location of the radiotelephone is stored in location memory 342, sequences of prefilc digits, if any, required to be concatenated to a primary telephone number may be concatenated to 3 5 portions of primary telephone numbers stored in memories 330 and WO 94/22260 ~ l ~ 4 ~ 'I & PCT/11594/01849 336 thereby parsing together a telephonic identification code required to initiate ef~ectuation of a communication link with a destination telephone associated with such parsed-together telephonic identification code.
S A user of radiotelephorle 300, the origination telephone, desiring to initiate ef~ectuation of a communication link with another telephone, i.e., the destination telephone, inputs, by way of keypad input 348, at least a portion of a primary telephone number. For instance, the user may input the final several digits of the primary 1 0 telephone number by way of keypad input 348.
Processing device 324 compares such sequence of digits with colTesponding dig~ts of the telephonic identification codes stored in stack and repertory memories 330 and 336. When the sequence of dig~ts input by the user of radiotelephone 300 matches a 1 5 corresponding ~equence of digits of the p~mary telephone number of a telephonic identification code stored in memory 330 or 336, such stored telephonic identification code iæ parsed into component portions and sequences of prefix digits are concatenated to, removed from, or substituted for, sequences of prefix digits, if any, forming 2 0 portions of the stored, telephonic identification code. Portions of the primary telsphone number are also truncated of~ of, or concatenated to, the portion of the primary telephone num~er of the stored telephonic identification code, if necessary.
Because the location of radiotelephone 300 is known (due to 2 5 storage OI data indicative thereof in location memory 342), appropriate sequences of prefix digits, namely an international access code and a country code, may be concatenated, if necessary, to the primary telephone number of the stored, telephonic identification .
code. ~nce a telephonic identification code required to permit 3 0 initiation of the effectuation of the communication link with the remotely-positioned telephonic apparatus has been parsed-together, such telephonic iderltification code is displayed by output display 354 and the telephonic identification code is transferred to transceiver f~, eircuitry 360 wherefrom a modulated signal representative of the 3 5 telephonic identification code is transmitted in conventional manner.

WO 94/22260 21:~ ~ 9 ~ 6 PCT/IJS94/01849 ~' FIG. 8 is a logical flow diagram of the method, referred to generally by reference numeral 500, of a preferred embodiment of the present invention. Method 500 parses together sets of sequences of~
digits to form a telephonic identification code of which a pr~mary S telephone number forms a portion. When the telephonic identification code is transmitted to a telephone system, initiation of effectuation of ~ communication link is permitted with remotely-positioned telephonic apparatus associated with the telephonic identification sode. First, and as indicated in block 506, a first set of 1 0 sequences of digits which form at least the portions of telephonic identification codes, is stored. In circuit 318 of FIG. 3, the first set of sequences of digits is stored in memory element 330 and/or memory element 336.
Next, and as indicated by block 512, a second set of sequences of 1 5 digits which form prefix digits of telephonic identification codes is stored. In circuit 318 of FIG. 7, such second set of sequences of digits is stored in location memory 342.
Next, and as indicated by block 518, at least part of a known portion of a primary telephone number of a selected, remotely-2 0 positioned telephonic apparatus is compared with corresponding parts of the first set of sequences of digits. Responsive to such comparison, a primary telephone number which corresponds with the at least part of the known portion of the primary telephone number is identified. In circuit 318 of FIG. 7, processing device 324is 2 5 operative to compare an input sequence of digits input by way of keypad input 348 with corresponding portions of telephonic identification codes stored in stack and reperto~y memories 330 and 336.
Finally, if required, and as indicated by bloclc 524, selected 3 0 sequences of digits which form the prefi~ digits are concatenated to at ~l least a portion of the primary telephone number identified responsive ~:
to the comparison between the known portion of the primary telephone number and the corresponding stored sequences of digits.
Thereby, a telephonic identification code is parsed together which 3 5 permits initiation of the effectuation of a communication link with WO 94/22260 2 1~ 4 g 7 6 PCT/U594/01849 the selected, remotely-positioned telephonic apparatus. As noted briefly hereinabo~e, in the preferred embodiment, processing device 324 comprises a microprocessor-type device. Algorithms e~ecutable by such microprocessor-type device compare the portions of th S primary telephone number input by a user by way of keypad i~put ~48 with corresponding digits stored in stack and repertory memories 330 and 336. Appropriate algorithms are also utilized to parse together a telephonic identification code which permits initiation of ef~ectuation of a commun~ication link between the radiotelephone and remotely-l O positioned telephonic apparatus.
FIG. 9 is a logical flow diagram of an algorithm executableduring operation of a preferred embodiment of the present invention.
The algorithm compares an input portion of a p~ma~ telephone number with corresponding digits of stored telephonic identification 1 5 codes. In FIG. 9 (and also FIG. 10 to be described hereinbelow), the acronyms "CC" and "IAC" are used to represent the terms country code and international access code, respectively.
- First, and as indicated by block 606, the algorithm is started when a user inputs a phone number. Then, as indicated by block 612, 2 0 the user actuates a particular key of the keypad input, here a FLAG
key to commence e~ecution of the steps of the algorithm. Ne~ct, at decision block 618, a detèrmination is made as to whether the dialing digits memory is empty (i.e., a determination is made as to whether no telephonic identification codes are stored in memory). If so ~i.e., if 2 5 no telephonic identification codes are stored in memory), the yes branch is taken to block 624 and the international access code for the current country of operation is displayed. E~cecution of the algorithm is then terminated.
If the no branch is taken from decision block 618, the memory 3 0 locations of the stack memory are scsnned, as indicated by block 630, to identify a phone number with digits corresponding to the portion of r`
the phone number input by the user. During the scan of each memory location of the stack memory, a determination is made, as '-indicated by decision block 636 as to whether a matching phone 3 5 number has been detected. If no matching phone number has been WO 94122260 2134 9 76 PCT/US94/01849 ``

found in the stack memory, the no branch is taken from decision block 636 to block 642 whereat the repertory memory is ~canned. A
determination is made, as indicated by decision block 648 as to whether a matching phone number was found during such scan. If no matching phone number was found, the no branch is taken from decision block 648 to decision block 654 where a determination is made as to whether at least one matching phone number is found in either stack or repertoIy memory. If not, the no branch is taken and execution of~ the algorithm is te~ninated as no matching telephone number has been found in memory.
If the yes branches are taken from either decision block 636 or 648, the identified phone number is parsed and displayed, as indicated by block 660. Block 660 is indicati~e of a parsing algorithm, the steps of which are shown in FIG. 10. The parsing algorithm, l S which shall be discussed more fully hereinbelow with respect to FIG.
10, is operative to parse together, i.e., piece together, a telephonic identification code.
Once an identified phone number is parsed and displayed, actuation of any keys of the keypad is monitored, as indicated by block 2 0 666. Then, as indicated by decision block 672, a determination is made as to whether any keys have been actuated. If not, the no branch is taken to decision block 678 whereat a dete~ll,ination is made whether a ten second period has elapsed without actuation of a key. If not, the no branch is ta~en back to block 666 until the ten 2 5 second period has elapsed; otherwise the yes branch is taken and execution of the algorithm is terminated.
If the yes branch is taken from decision block 672 indicating that a key has been actuated, a determination is made, as indicated by decision block 679 whethe~ the key, detected to have been actuated, 3 0 was a particular key, namely an "asterisk" key. A user actuates the asterisk key when the user desires not to select the displayed, telephonic identification code, but, rather, desires continued ea:ecution of the algorithm to attempt to select another stored number. If the asterisk key is not actuated, the no branch is taken 3 S and execution of the algorithm is terminated. If the yes branch is W(~94/2226~ 1; PCTIU594/01849 !~:~

taken, a determination is made, as indicated by decision block 684 as to which memory is being scanned. Responsive to such determination, a branch is taken to either block 630 or 642.
E~ecution of the algorithm of FIG. 9 permits a telephonic r 5 identification code stored in either stack or repertory memo2y which corresponds to an input sequence of digits to be identified.
FIG. 10 is a flow diagram of an algorithm executable by a microprocessor-type device to parse together (i.e., piece together) a telephonic identification code which permits initiation of ef~ectuation l 0 of a communication link with remotely-positioned telephonic apparatus. While the flow diagram of FIG. 10 is described with particular reference to a radiotelephone operable in the telephone systems of the Nordic countries, analogous flow diagrams may be constructed ~or operation in other telephone systems.
1 5 Once a telephonic identification code stored in either stack or repertoly memory has been identified responsive to execution of the algorithm of FIG. 9, the stored, telephonic identification code is recalled for parsing, as indicated by block 806 of FIG. 10. (As noted pre~iously, the parsing algo2ithm is e:~ecuted at block 660 of FIG. 9.) 2 0 Once recalled, and as indicated by block 812, the parsing algorithm commences.
First, a determination is made, as indicated by decision block 818, as to whether the stored, telephonic identification code (i.Q., the phone number recalled for parsing) contains at least four dig~ts. If 2 5 not, the no branch is taken to decision block 824 whereat a determination is made as to whether the location at which the country code of the phone number matches the country wherein the recalled number was stored. That is, a determination is made as to s.
whether the country code associated with the stored, telephonic 3 0 identification code corresponds with the present location (the operational country) of the radiotelephone. If so, the yes branch is taken and e~cecution of the algorithm is terminated as the stored, telephonic identification code is identical to the telephonic identification code required to initiate effectuation of the 3 5 communication link with the selected, telephonic apparatus.

W0 94/22260 ~ 13 ~ 9 7 6 PCT/11594/01849 '~

If the no branch is taken from decision block 824, when the country code of the stored, telephonic identification code is dissimilar with the present location of the position of the radiotelephone, a dete~nination is then made, as indicated by decision block 830, as to S whether the stored, telephonic identification code includes a dcml~stic dialing code of the destination country as a portion thereof. If so, the yes branch is taken, and the direct dialing code digits are truncated from the stored, telephonic identification code. Then, the sequence of pref~ digits ~f the countly code of the country of the stored, 10 telephonic identification code are concatenated to the primary telephone number portion of the stored, telephonic identification code. And if the stored, telephonic identification code as determined by decision block 830, does not include a domestic dialing code as a portion thereof, the ~equence of digits comprising the country cocle of 1 5 the location-countrg wherein the stored, telephonic identification code was stored in memory is concatenated directly to the primary telephone number of the stored, telephonic identification code in block 842.
Then, as indicated by block 848, the sequence of prefL~c digits 2 0 corresponding to the international access code of the country in which the radiotelephone is presently locPted is concatenated to the telephonic identification code formed during e~ecution of block 842.
A telephonic identification code re~uired to initiate effectuation of a communication link with the selected, telephonic apparatus, and 2 5 e~ecution of the algorithm may be terminated.
If the yes branch is taken from decision block 818, a determination is made as to whether the first digits of the stored, telephonic identification code are comprised of a sequence of prefix digits fo~ning an international access code. If not, the no branch is 3 0 taken to decision block 824; if yes, the yes branch is taken from decision block 854 to decision block 860. ~ -At decision block 860, a dete~nination is made as to whether the country code of the stored, telephonic identification code matches the country code of the count~y in which the radiotelephone is 3 5 presently located. If not, the no branch is taken to decision block 866 WO 94/22260 2 I ~ ~ 9 7 G PCT/US94/01849 whereat a determination is made as to whether the stored, international access code matches the international access code of the country in which the radiotelephone is presently located. If yes, the yes branch is taken, and execution of the algorithm is terminated ;j S as the sto.ed, telephonic identification code forrns the telephonic identification code required to initiate ef~ectuate of a communication link with the selected, telephonic apparatus.
If not, the no branch is taken from decision block 866 to block 872 whereat the international access code of the stored, telephonic identification code is removed, and substituted with the international access code of the country in which the radiotelephone is presently located, and execution of the algorithm is then terminated.
If the yes branch is taken from decision block 860, both the inte~national access code and the country code are removed from the 1 5 stored telephonic identification code, as indicated by block 878. Then, as indicated by decision block 884, a determination is made as to whether the operational country, that is, the country in which the radiotelephone is located uses a domestic dialing code. If yes, the yes branch is taken to block 890 whereat the domestic dialing code is 2 0 concatenated to the prima~y telephone number and then e~ecution of the algorithm is terminated. If the no branch is taken from decision block 884, the no branch is taken, and execution of the algorithm is similarly terminated.
Because circuit 318 of the present invention and radiotelephone 2 5 300 incorporating such circuit permit parsing together of a telephonic identification code required to initiate effectuation of a communication link with any selected, telephonic apparatus, while not requiring each possible telephonic identification code to be stored t in memory elements of the radiotelephone, dialing of the desired 3 0 telephonic identification code is facilitated.
Operation of the algorithm of FIG. 10 to parse together a telephonic identification code may be illustrated with the e~amples of ,~
FIGs. 4-6. The telephonic identification codes of the second-listed e~amples of each of the figures may be parsed together once the 3 5 telephonic identification codes of the first-listed examples of such WO 94/2;2260 213 4 9 7 6 PCT/USg4/01849 ~ ~

figures are stored in memory 330 or 336 of circuit 318. When a user enters digits corresponding to the at least portion of the telephonic identification code stored in memory, the algorithm of FIG. 9 selects the stored telephonic identification code as a match with the user- ¦
5 entered digits. The selected telephonic identification code is pro~ided for operation of the parsing algorithm of FIG. 10.
With particular respect to the e~camples of FIG. 4, if the first-listed telephonic identification code is identified as the match with the user-entered digits, the second-listed telephonic identification code I O may be parsed-together therefrom. In execution of the algorithm, the no branch is taken from decision block 854, then decision block 824.
The domestic dialing code is truncated after talcing the yes branch from decision block 830 at block 836. The country code and international access codes are concatenated to form the telephonic 1 5 identification code at blocks 842 and 848.
With particular respect to the e2camples of FIG. 5, if the first-listed telephonic identification code is identified as the match with the user-entered digits, the second-listed telephonic identification code may also be parsed-together therefrom. In e~ecution of the 2 0 algorithm, the yes br~nches are taken from decision blocks 8~4 and 860. Then, the international access code and the country code are truncated at block 878, and the yes branch is taken from decision block 884 and the domestic dialing code is added at block 890 to form the telephonic identification code.
2 5 And, with particular respect to the e~amples of FIG. 6, if the first-listed tele~honic identification code is identified as the match with the user-entered digits, the second-listed telephonic identification code may be parsed-together therefrom. In e~ecution of the algorithm, the yes branch is taken from decision block 854, then 3 0 the no branch is taken from decision block 860. Thereafter, the no branch is taken from decision block 866, and the international access ~~
code is replaced at block 872 to form the telephonic identification code.
While the present invention has been described in connection with the preferred embodiments shown in the various figures, it is to 3 5 be understood that other similar embodiments may be used and WO 94/2~60 2 1 3 ~ 9 7 6 : PCT~594/01849 ~

modifications and additions may be made to the described embodiments for performing the same function of the present invention without deviating therefrom. Therefore, the present invention should not be limited to any single embodiment, but rather 5 construed in breadth and scope in accordance with the recitation of the appended claims.

, .

Claims (10)

What is claimed is:

1. A circuit operable with origination telephonic apparatus, said circuit for forming a telephonic identification code of which a primary telephone number forms at least a portion and which, when transmitted to a telephone system, permits initiation of effectuation of a communication link with destination telephonic apparatus associated with the telephonic identification code, said circuit comprising:

means for storing a first set of sequences of digits which form at least the portions of telephonic identification codes which comprise primary telephone numbers;

means for storing a second set of sequences of digits which form prefix digits of telephonic identification codes;

means for comparing at least part of a known portion of a primary telephone number of a selected, destination telephonic apparatus with corresponding parts of the first set of sequences of digits stored by said means for storing the first set and for identifying a primary telephone number stored therein which corresponds with the at least part of the known portion of the primary telephone number; and means for parsing together the telephonic identification code which permits initiation of the effectuation of a communication link with the selected, destination telephonic apparatus, wherein at least a portion of the telephonic identification code parsed together thereat is formed of at least a portion of the primary telephone number identified by said means for comparing.

2. The circuit of claim 1 wherein said means for storing the first set of sequences of digits comprises at least one memory element for storing a plurality of the at least portions of the telephonic identification codes which comprise the primary telephone numbers.

3. The circuit of claim 2 wherein said means for storing the first set of sequences of digits further comprises means for inputting the sequences of digits comprising each of the at least portions of the telephonic identification codes which comprise primary telephone numbers.

4. The circuit of claim 3 wherein said means for inputting the sequences of digits comprises a telephonic keypad comprised of a plurality of manually-actuatable actuation keys.

5. The circuit of claim 1 wherein the sequences of digits forming the prefix digits stored by the means for storing the second set comprise digits corresponding to access codes which permit telephonic apparatus located in a first telephonic system to access a second telephonic system.

6. The circuit of claim 5 wherein the sequences of digits forming the prefix digits stored by the means for storing the second set further comprise digits corresponding to identifying codes which identify the second telephonic system.

7. The circuit of claim 1 wherein said means for comparing comprises a processing device having an algorithm embodied therein operative to compare the at least part of the known portion of the primary telephone number associated with the destination telephonic apparatus with the corresponding parts of the first set of the sequences of digits forming the primary telephone numbers stored by said means for storing the first set.

8. The circuit of claim 1 wherein the at least part of the known portion of the primary telephone number associated with the destination telephonic apparatus compared by said means for comparing comprises at least one digit of the primary telephone number associated with the destination telephonic apparatus.

9. The circuit of claim 1 wherein said means for parsing further comprises means for truncating selected digits off of the primary telephone number identified by said means for comparing, thereby to form the portion of the primary telephone number to which the selected sets of prefix digits are concatenated.

10. A method for parsing together sets of sequences of digits to form thereby a telephonic identification code of which a primary telephone number forms a portion and which, when transmitted to a telephone system, permits initiation of effectuation of a communication link with destination telephonic apparatus associated with the telephonic identification code, said method comprising the steps of:

storing a first set of sequences of digits which form at least the portions of telephonic identification codes which comprise primary telephone numbers;

storing a second set of sequences of digits which form prefix digits of telephonic identification codes;

comparing at least part of a known portion of a primary telephone number of a selected, destination telephonic apparatus with corresponding parts of the first set of sequences of digits stored during said step of storing the first set and identifying a primary telephone number which corresponds with the at least part of then known portion of the primary telephone number; and, if necessary, parsing together the telephonic identification code which permits initiation of the effectuation of a communication link with the selected, destination telephonic apparatus.