Abstract:
A method and apparatus for automatic creation of an electronic telephone directory uses intelligent automatic recognition of whether a telephone number is considered by the user as an important one or not. A telephone number is recognized to be an important one when certain user actions or situations relating to this telephone number occur. These include calling back a Caller ID number repeatedly or a certain number of times within a certain time period, receiving the same Caller ID number repeatedly within a certain time period, manually dialing a number that matches one of those in the memories; or, during a Caller ID on Call Waiting, exercising options like dropping the existing call and switching to the new caller, etc. Once a telephone number is determined to be an important one based on these criteria, the number is automatically stored into a permanent memory that is the electronic directory.

Description:
PRIOR ART AND BACKGROUND OF THE INVENTION 
     The present invention relates to the automatic creation of an electronic phone directory via Caller Identification (“Caller ID”) data and via manual dialing of telephone calls. It also relates to remote access of Caller ID and directory data, either via a dedicated hand-held unit, or via audible means over an ordinary telephone. 
     Caller ID service has become popular in recent years. Most Caller ID units have a Caller ID memory, and the data of the incoming calls is stored into the memory in a “first-in-first-out” sequence, i.e. when the memory is full, the data of the oldest caller is erased to make room to store the data of a new incoming call. Some units also have a second memory for permanent storage of data transferred from the Caller ID memory. However, the transfer is usually manually actuated. Furthermore, to access the Caller ID memory, the present Caller ID products use a “scroll up” and a “scroll down” key. This method of access is not convenient when the capacity of the memory is large and full of numbers. 
     The number of a caller sent by the phone company usually includes an area code of the area where the call originates, even if it is a local call. Thus, for local call-back dialing, the area code may have to be excluded. To exclude the dialing of the area code, many Caller ID units require the storage of area code numbers of the user&#39;s location into the memory. When the caller makes a call, the unit will compare the area code of the dialed number with the stored area codes. If they are the same, the area code will not be dialed. As quite a few area codes have to be pre-stored, particularly with the advent of “overlay” area codes, the manual storage of area codes is also tedious. 
     Moreover, “talking Caller ID” or “voice Caller ID” devices exist which plays an audible announcement of the Caller ID information when a call is received, or when reviewing a Caller ID from a list. The number and/or name of the Caller ID is played using voice, so that the user can know the identity of the caller just by listening to the announcement, without having to look at the display screen of the caller ID device. However, such techniques are useful only when the user is at his/her home or office. The voice announcement of Caller ID can only be heard if the user is at the same room/location as the Caller ID device. If the user is on-the-road or otherwise in a remote location, the Caller ID information becomes inaccessible. Similarly, there is no easy way for a user to remotely access the directory stored at a telephone located at a user&#39;s home or office. 
     SUMMARY OF THE INVENTION 
     The present invention provides an improved electronic telephone directory that provides a telephone user greater convenience than is available with prior art units. 
     The first aspect of the present invention is directed to a method and apparatus for automatic selection of those important/frequently used phone numbers and for automatic transfer of them to a permanent memory. A phone number related to certain operation is defined as an important/frequently used number under one or more of the following criteria: 
     (1) a number from Caller ID memory has been called back for one or more than “n” times within a certain length of time; 
     (2) a Caller ID number has been received repeatedly after and before a certain length of time (e.g. after 5 hrs and before 48 hrs.) for 2 or more than “n” times; 
     (3) a number is repeatedly dialed out after and before a certain length of time (e.g. after 5 hrs and before 24 hrs.) for 2 or more than “n” times; 
     (4) the last 7 digits of a manually dial out number is found to be matched with the last 7 digits of a number in Caller ID memory; and 
     (5) For Caller ID on call waiting, that is, a Caller ID of a third party which is received while the user is already engaged in a telephone call, the user has at least 2 options to handle this new call. One option is to ignore this new call, and the other option is to accept the new call and switch to talk to the third party. If the present invention detects and records that a user has manually accepted such a call-waiting, the number found in the Caller ID on call waiting of this call is auto determined to be an important telephone number. 
     Another aspect of the invention is directed to automatic deletion of numbers. When the memory is full, those numbers which have not been dialed for 6 or “n” months or those with least dialing times are automatically deleted except those numbers which with VIP flag are kept for permanent storage. 
     Yet another aspect of this invention is to provide a method and apparatus for automatic storage of a list of area codes. All received Caller ID numbers will be compared with a list of manual dial out and actual call back numbers. The area codes will be extracted and then add to the memory list of area codes. 
     A further aspect of the present invention is to provide a method and apparatus for remote access of Caller ID and directory data. In a first embodiment, a portable hand-held unit is provided to allow the user to access Caller ID and directory information when the user is on-the-road. 
     In accordance with other factors, the invention enables remote access of Caller ID&#39;s and possible directory information by a portable hand-held unit, or by playing a voice announcement of Caller ID and directory data to an ordinary telephone via telephone line. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The preferred embodiment of this invention will be described in detail in conjunction with the following drawings, in which: 
     FIG. 1 is a functional block diagram of the electronic telephone directory according to the present invention and utilizing a base unit and a hand held unit. 
     FIG. 2 is a flow diagram of the routines of processing of “important Caller ID” data and the storage of that data into the directory memory. 
     FIG. 3 is a flow diagram of the routines of storing a called back Caller ID data into the directory memory. 
     FIG. 4 is a flow diagram of the routines for auto storing an “important/frequently manual dialed” number into the directory memory. 
     FIG. 5 is a flow diagram of the routines for automatic deletion of a number when it is least important. 
     FIG. 6 is a side view of the base unit and the plug-in/out hand held unit. 
     FIG. 7 shows a detailed flow diagram of automatic storage of area codes. 
     FIG. 8 is a flow chart for showing the process how calling back a number in Caller ID can be made more convenience and automated by intelligence addition to or removal of area code. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 of the drawings shows a functional block diagram of an electronic telephone directory of the present invention, which includes a base unit  101  and a hand held unit  102 . The base unit includes a Caller ID Receiver  103 , a dialing signal detector  105 , a microprocessor  106 , and a keypad  107 . It also contains a ring detector  128  for detecting the presence of ringing on the telephone line. A speech synthesizer or sound recording/reproducing unit  129 , which can be controlled by the microprocessor, is connected to the telephone line for playing voice announcement over the telephone line. The hand-held unit includes a microprocessor  112  having a DSP (digital signal processing) capability, a DTMF generator  110 , a LCD display  111  and a keypad  108 . The hand-held unit is portable for on-the-road use. 
     Both the base unit  101  and the held-held unit  102  contains a Transmitter &amp; Receiver, namely  104  and  127 . They can be used for transmitting information between the two units. Dialing is also accomplished with the Transmitter/Receiver units  104 ,  127 . 
     The Caller ID receiver  103  receives and converts the Caller ID signals and sends it to microprocessor  112  or  106  for processing. The method and circuitry for processing of receiving, storing, retrieving and calling/dialing back of Caller ID data are conventional known and commercially available. 
     These units  101  and  102  can be combined into a single unit in case a hand held/carry unit is not required. In that case, the microprocessor  106  and keyboard  107  can be omitted, and detector of block  105  may also be omitted and held unit  102  could be a plug-in/out unit into the base. This architecture enables the method of this invention to be flexibly used with any apparatus which contains an electronic phone directory. 
     There are several memories that are used in the base unit: a Redial Numbers Memory  114 , a Caller ID Memory  115 , and a permanent Directory Memory  116 . The Redial Numbers Memory  114  stores a list of numbers that have been recently dialed by the unit. The Caller ID Memory  115  stores the Caller ID data received from the telephone line. The Directory Memory  116  stores telephone numbers and names which are automatically created in a novel way as disclosed in the present invention. The Redial Memory  114  and Caller ID Memory  115  can typically implemented using conventional volatile memory technology such as static RAM, while the Directory Memory  116  is usually implemented using permanent memory technology such as EEPROM or flash memory. The hand-held unit contains “mirror” Redial Memory  124 , Caller ID Memory  125  and Directory Memory  126 . The data in each of these “mirror” memories are mirror copy of the corresponding memory areas in base unit  101 . 
     FIG. 2 shows a detailed flow diagram of the routines of processing an “important” Caller ID data and storage of the data into the permanent memory directory. When a Caller ID data is received, as shown in step  201  of FIG. 2, microprocessor  112  or  106  of FIG. 1, will examine, at step  202 , if there is the same number in Caller ID Memory  115 ; and, if the same number was received after m hours and before n hours, and will further examine at step  203 , if the same number is in Redial Memory  114 . If either test results in a YES, the data will be further examined at step  206 , to see if a name is included. If it is included, the data will be processed at step  208  for adding a flag of “store into directory” to the data and then sent to store into the Caller ID Memory as shown at step  209 . When the Caller ID Memory is full, the oldest caller&#39;s data will be removed from the Caller ID Memory. It is then further examined at step  210  to see if a “store into directory” flag is included; and, if YES, then the data will be stored back into the Directory Memory  116 . If the flag is not present, the data will be deleted and discarded as shown at step  211 . 
     If at step  206 , if the answer is NO, as shown at step  207  a prompt of “Enter name” which for/showing in LCD with the number will be add to the data/number and then further processed at step  208  as previously mentioned. 
     If at step  203 , if the answer is NO, the microprocessor will further examine, at step  204 , whether the same number is in the directory but without a name. If the answer is YES, the number will also further processed as shown at step  207 , as mentioned previously. 
     As shown in block  213  of FIG. 2, the alphanumeric key board of  107  or  108  of FIG. 1 not only can be used to access the Directory Memory  116 , but also can be used to access the Caller ID Memory  115 . This arrangement not only helps to quickly and easily search for a desired phone number, but also enhances the efficiency of using of memory capacity. 
     It should be noted that Caller ID can be classified into two types. Caller ID which is received when the phone is not in-use (on-hook), and which is usually accompanied by ringing, is called type I Caller ID. Caller ID which is received when the phone is already in-use (off-hook); that is, when the user is already engaged in a telephone conversation with a second party, is called type II Caller ID, or Caller ID on Call Waiting. The type II Caller ID provides another opportunity for determining if a telephone number is important or not. 
     When Caller ID on Call Waiting is received, a telephone user has at least two options on how to treat the new call. The first option is to ignore the new call, and continue the existing telephone conversation. Obviously, in this case the user thinks that this new call is unimportant. The second option is to accept the new call, to switch to talk to the new call-waiting caller, and put the call of the second party on hold. The fact that the user decides to interrupt an existing call to switch to the new third party caller, after seeing the Caller ID of the new caller, is a strong suggestion that the caller considers this telephone number an important one. Hence, the present invention can be made to automatically mark the Caller ID of these manually accepted call-waiting call as important, and store the number into the Directory Memory  116 . To do this, the Dialing Signal Detectors  105  must monitor any “flash” signal which is used for switching to another caller during call waiting. If the “flash” signal, which is usually generated when a user manually presses a “flash” key to accept a call-waiting, is detected, then the Caller ID received by Caller ID Receiver  103  during the call waiting is determined by the microprocessor  112  as an important number, and can be stored into the Directory Memory  116 . The routine for automatically storing such important Caller ID on call waiting into the Directory Memory is very similar to that described in the flow chart of FIG.  2 . In fact, it is entirely possible to use the same routine to store this important Caller ID on Call Waiting, by requiring this kind of call only has to be received one time within a certain time period for it to be considered important. The important Caller ID on Caller Waiting data is thus automatically stored into the permanent directory memory. 
     Furthermore, more advanced Caller ID technology, sometimes known as type 2.5 gives the user even more options and flexibility in handling a call-waiting call. Besides the two options described, additional options are made available to the users. One of them is “Take Message”. Under this option, the new call-waiting caller is redirected to a voice mail system, so that the call-waiting caller can leave an voice recording. It is also possible to redirect the call to any other telephone number, for example to a human telephone receptionist. Another option is to “Play Announcement”. If this option is selected, a voice message will be played to inform the call-waiting caller that the user is unavailable to take the call, and then the new caller will be disconnected. Yet another option is called “Drop Current Call.” A user may select this option to disconnect the call with the existing second party, and switch to talk to the new caller instead. The fourth option is “Conference.” This option allows the new call-waiting call and the existing call to be joined into a telephone conference, so that all the three parties can talk to each other at the same time. 
     If the user&#39;s telephone line is equipped with this more advanced type 2.5 Caller ID technology, the option manually selected by user during call-waiting can also be recorded by the present invention, and the Caller ID number can be determined to be important or not, and be transferred to the directory memory accordingly. Obviously, if the user selects the “Take Message” or “Play Announcement” option to handle a call-waiting call, this indicates that the user thinks the telephone call is mostly unimportant. On the other hand, if the user selects the “Drop Current Call” option to switch to talk to the new caller, or selects the “Conference” option to join the new caller into a telephone conference, certainly the user regards the call-waiting caller as highly important and worthy of his/her immediate attention. The present invention can thus be made to determine that call-waiting call handled by the user in these ways as important, and store them into the directory. To ensure call-waiting calls handled by these additional options are determined as important, it can be easily implemented in the same way as that for the two basic call-waiting options as described above. The Dialing Signal Detectors  105  can be made to monitor the signals generated when the user selects the “Drop Current Call” or “Conference” options. Usually, the signal generated when the user press keys to select one of these actions are “flash” plus DTMF ‘7’, and “flash” plus DTMF ‘3’, for the “Drop Current Call” and “Conference” options respectively. If these dialing signal are detected during call-waiting, the Caller ID number received for the call-waiting is determined to be important, and is thus stored into the telephone directory. 
     In a similar manner, it is also possible to determine if a type I (on-hook) Caller ID number is important or not, by having the present invention to monitor and record if the user picks up the handset to answer the call or not. Circuit to detect if a telephone line is in-use is well known in the arts. If, after a on-hook Caller ID is received, it is found that the telephone line becomes in-use, it is obvious that the user has answered that call, so the Caller ID number is probably considered by the user to be an important one. Hence, the present invention can be made to automatically store these Caller ID numbers of answered calls into the telephone directory. Similarly, if it is found that the telephone line does not become in-use within a short time period after a on-hook Caller is received, this indicates that the user decided not to answer the call, and the Caller ID number must have been an unimportant one. Furthermore, using the method similar to that in the flowchart of FIG. 2, it is not necessary to treat the Caller ID number of all answered call as important. It can be made in such a way that, only if a call of same Caller ID number is received and answered by the user repeatedly after and before a certain length of time (e.g. after 5 hrs and before 48 hrs.) for 2 or more than “n” times; then the Caller ID number is determined to be important, and automatically stores into the telephone directory. 
     FIG. 3 is a detailed flow chart of the routine of storing a calling/dialing back Caller ID data into a permanent Directory Memory  116 . When a Caller ID number is called/dialed back from the Caller ID Memory for 1 or n times, as shown in step  301  of FIG. 3, and is detected by microprocessor  112  or  106  then, at step  302 , the microprocessor will further examine, whether the number is included with a name or not. If it is included, the number and name will be stored into the directory memory RAM of block  116  of FIG. 1 immediately as shown at step  306 . Currently, most Caller ID services provide both number and name delivery service. However, if the number is not included with a name, microprocessor  112  or  106  will prompt the user to key in a name and then store into the directory as shown at steps  303  to  306  of FIG.  3 . 
     As shown by a dotted line  307 , steps  304  and  305  can be skipped by automatically adding the prompt of “Enter name” to the number and then storing the number with the prompt into the directory. The skipping of these steps may be automatically performed simply after a certain time delay without any key pressing, and the name of such number may entered later by the user or automatically entered when there is an incoming call of same number with name, and such processing will appear as shown at step  204  of FIG. 2 as previously mentioned. 
     As also shown by dotted line  308 , step  304  may also be skipped by itself, i.e. the user can press the STORE key to end the storage if the user is reluctant to key in a name at the moment. 
     FIG. 4 shows a detailed flow diagram of the routines for automatically storing an important/frequently manually dialed number into the Directory Memory  116 . 
     In the present invention, the Redial Number Memory  114  of FIG. 1, is provided for storage of a list of dialed numbers. These numbers can be used for redial, and are also used for selecting important/frequently dialed numbers and auto transfer the selected numbers into the Directory Memory  116 . 
     After completion of the manual dialing a number and the end of a call (and the hanging up of the receiver), the microprocessor will store the number into the Redial Number Memory  114  as shown at steps  401  and  402  of FIG.  4 . And at step  403 , the microprocessor will examine, whether the number is matched with any number in the Caller ID Memory  115 . If there is a matched number, this number with its other data in the Caller ID Memory  115  will be further examined as shown in step  302  and further processed as shown at steps  303  to  306  of FIG.  3  and then stored into the Directory Memory  116 . 
     If there is not a matched number in the Caller ID Memory  115 , as shown at step  404 , the microprocessor will examine if the number matches with a number in the redial numbers memory stored for within n hour(s) (and after m secs.). If YES, the number will be further processed as shown at step  303  to  305  and then stored into the directory. 
     FIG. 5 shows a flow chart for the detail routines for automatically deleting a number and its associated data for making room for a new entry when the directory memory is full. When a new entry is started, the microprocessor will examine at step  502  of FIG. 5 whether the directory memory is full or not. If YES, as shown at step  504 , the microprocessor will search for a number which has not been dialed for the longest time and then examine at step  505 , whether the number has a VIP flag. If NO, the microprocessor will further examine at step  508 , whether it is has not been dialed for more than m months. If YES, as shown at step  509 , this number will be deleted. If NO, as shown at step  510 , a visual indicator or sound alerting signal or both for full of memory will be activated. 
     With regard to step  505 , if the number has a VIP flag, which is defined as not for automatic deletion, then, at step  506 , the microprocessor will further examine, whether it is a last/recently stored number. If YES, it will be processed to a same step  510 . If NO, as shown at step  507 , the microprocessor will search a number in the directory which has not been dialed for next to the previous longest time and then repeat the processing of step  505  and the following steps again. 
     This invention also provides a method and apparatus for automatic storage of area codes. All received Caller ID numbers will be compared with a list of manual dial out and/or actual call back (from Caller ID Memory) numbers. The area code will be extracted and stored to add it to the list of area codes. The list of numbers for comparison must be the numbers of a “successful” call. The way to judge whether or not a call is a successful call is to check, after completion of dialing, if there is time for conversation. The way to check this is to check the length of time from the end of completion of dialing to the start of hang up of the telephone line. Thus, if it takes more than 30 seconds, it is deemed to be a successful call. 
     The list of the successful call numbers exists in the Redial Numbers Memory  114  and Directory Memory  116 . The method for processing of comparison and extraction of area code data and the storage into the memory is shown in FIGS. 7 and 8 and is similar to the processes discussed earlier. 
     FIG. 7 shows a detailed flow diagram for the automatic storage of area codes. Every time an outgoing call is determined by the microprocessor as a successful call at step  701 , the number dialed for that call is extracted from the redial numbers memory  114  at step  702 . At step  703 , if the number consists of 7 digits or less, then the number dialed has no area code, and it is dismissed at step  704 . If the number has more than 7 digits, the first n digits, where n is normally 3, is added to area code memory  117 . 
     FIG. 8 is a flow chart showing how the process of calling back a number in Caller ID can be made more convenient and automated by intelligence addition to or removal of area code. At step  801 , every time a user requests a number in Caller ID Memory  115 , the area code of the number is first extracted at step  802 , and then compared with the multiple area codes stored in the Area Code Memory  117  at step  803 . If the area code of the Caller ID/redial number matches one of the entries in the Area Code Memory  117 , then it is known that the number is outside of the user&#39;s area. A prefix of digit “1” is added to the number at step  804 , as usually required by long distance calls. The modified number, including the “1” prefix and the area code, is then dialed to make a call. On the other hand, if the area code of the Caller ID/redial number has no matched entry in the Area Code Memory  117 , then it is impossible to determine whether the number is inside or outside the user&#39;s area from the dialing history of the user. At this point, at step  805  a prompt can be displayed in the LCD to ask if the user wants to remove the area code from the number before dialing. If the user presses a button to indicate yes, then, at step  806 , the area code is removed from the number. At step  807 , the modified number is dialed. 
     Any number that is stored into the Redial Memory  114  and Directory Memory  116 , and which originates from manual dialing, should be a successful call and which can be further examined and processed simply as just mentioned above. Area codes can be extracted from the number stored in these memories, and then stored in the area code memory. 
     As mentioned and shown in FIG. 1, block  102  of FIG. 1 can be a plug in/out hand held/carry unit. This architecture enables the method and apparatus of this invention to be used and combined with any apparatus which with electronic phone directory. Beside corded, cordless and mobile telephones and telephone add-on devices, other apparatus, such as data banks, organizers, PDAs (personal data assistant), hand-held computers and even traveling clocks, can use the method of this invention to automatically create a phone directory. 
     However, the plug-in architecture in only one of the architectures of the present invention. The base unit  101 , including a microprocessor block  106  and a keyboard  107 , can do all of the processing for the electronic directory. The created phone directory will be stored in the Directory Memory  116  which is connected to the microprocessor  106 . Many recent microprocessors are available which provide build-in small and medium size RAM: for example, the Zilog Z8 series. In this case, to transfer the data of the directory from base unit  101  to hand held unit  102  needs only to use a single Input/Output port. Thus, the data transfer can simply be done using a wire pair or via a single channel of infrared or Radio Frequency (RF) signal. It can also be transferred via the telephone line by Dual Tone Multiple Frequency (DTMF). Or, Frequency Shifted Keying (FSK) coding and decoding can be used to enhance the reliability of data transfer. The coding/decoding of FSK can be simply processed by the microprocessor with built-in Digital Signal Processing (DSP) capability, as shown in block  112  of FIG.  1 . And in this embodiment, remote data transfer can be performed. 
     Part of the circuitry, e.g., the Transmitter &amp; Receiver circuitry of block  104  of the base unit  101  of FIG. 1 can be built as a small plug-in accessory, or the hand-held/hand carry unit can be combined with the Transmitter &amp; Receiver circuitry and with a telephone jack. This accessory or combined hand-held unit can be used to plug into any telephone line, and dial a call/number to the base unit, and then send/dial a corresponding code for transferring a corresponding selection of data, e.g., the data of all calls or the data of only the new calls from the Caller ID memory of the base unit via the telephone line. 
     In a further embodiment of the present invention, an audio/voice facility is also added for audible presentation of the Caller ID and directory data. Any data, such as the name and numbers of the Caller ID, can be audibly alerted and announced. When the user review the Caller ID, in addition to displaying the Caller ID data on the screen, a speech synthesizer can also used to spell out the digits of the number in the Caller ID, and announce it via a speaker. This technology is commonly called “Voice Caller ID” or “Talking Caller ID”, and one example can be found in the U.S. Pat. No. 5,265,145 from the same inventor of the present invention. Speech synthesizers commonly available in the market, or voice record/reproducing IC, or microprocessor with build-in DSP capability like block  112  of FIG. 1 can be utilized for converting the Caller ID data into audible speech. 
     As a further extension to the invention, any data from the base unit can be remotely audibly accessed by any telephone by dialing a phone call. The user can hear via the handset of the remote telephone the audible announcement of the number and/or name contained in the Caller ID, for the calls that have been received by the base unit. Before the user leaves his/her home or office where the base unit is located, the user first sets a switch on the unit to tell the unit to automatically answer a call to provide remote voice Caller ID after a number of ringing. Then, when the user is on the road, the user can make a phone call to the unit using, for example, a public pay phone, to hear the Caller ID of any call that the base unit received while the user was away. After the base unit automatically answers the call, a voice prompt can be played to the user via the telephone line: for example, “Enter the pass code.” The user can use the digit keypad on the remote payphone to enter a 3 digit pass code. The digits are transmitted by DTMF tone via the telephone line. The base unit will decode the DTMF tone to obtain the pass code. If the pass code is incorrect, the base unit will automatically hang-up and terminate the call. If the pass code is correct, the base unit will play an audible announcement to tell the user how many new calls have been received, for example, “You have Six New Calls”. The base unit will then proceed to play an audible announcement of the number and/or name, time and date of new Caller ID received in turns. For example, the base unit may play an voice announcement for the first Caller ID, “Call One, one-two-three-five-five-five-one-two-one-two, at nine-thirty AM, on twenty first of March.” If the Caller ID includes name information, the name can also be spelled and played; or, alternatively, if the user had pre-recorded a voice representing the name that is associated with the Caller ID number, the pre-recorded voice can be played. 
     The user at the remote payphone may instruct the base unit to play the next Caller ID or the previous Caller ID by issuing commands via the digit keypad of the payphone. For example, if the base unit received a DTMF tone “1” sent from the payphone, it will be interpreted as a command for listening to the next voice Caller ID. The currently playing voice Caller ID will be interrupted, and the voice announcement of next Caller ID will be played instead. Similarly, if the user wants to hear the previous voice Caller ID again, the user can press the “2” digit key. Upon receiving the DTMF tone from the payphone, the base unit will play the voice announcement of the previous Caller ID. 
     The present invention can also be used for remote audible announcement of directory entries. Instead of number and name contained in Caller ID, the number and name in a directory entry can be played by voice announcement. The name in the directory can be spelled out, or the user can be required to speak the name in his/her own voice while adding the entry to the directory. The user&#39;s voice is recorded by base unit, which is then converted into digital form and stored in a voice memory. Then, when a voice announcement of the directory entry is to be played, the pre-recorded voice that was stored in the voice memory are converted back to audible voice, and played via the telephone line to the user. 
     In addition to playing all the entries in the directory one-by-one, further commands can be provided to allow easier access of the directory. For example, when the user presses “*01” in the keypad of the remote telephone, the base unit will respond by playing directory entries whose name begin with the character “A”. Similarly, when the user presses “*02” in the keypad of the remote telephone, the base unit will respond by playing directory entries whose name begin with the character “B,” etc. 
     In accordance with additional features of the invention, the base unit can be provided with power charging facility for charging the battery of the hand held unit when it is plugged in. The Dialing Signal Detectors  105  are used to detect/decode other dialing numbers by other telephones connected to the same telephone line. The method and circuitry of this block is also conventional and known. The number detected/acquired by this detector will be processed by the Microprocessor  112  for the automatic creation of phone directory, just as processing the number dialed by the Key Board  108  or  107 . This detector will speed up the automatic creation of phone directory. However, it is an optional functional block. 
     If instead of an ordinary telephone, the user makes use of the hand-held unit  102  to place a call to the base unit  101 , then it is not necessary to use audible means for accessing the Caller ID or directory information in the base unit. Instead, as mentioned before, because the Hand-held Unit  102  can be equipped with a transmitter-receiver unit, it can access the Caller ID or directory information in the base unit  101  by faster electronic means. For example, signal modulation using FSK modulation can be used for accessing the data. The process of remote access is very similar to that of using audio means. The user at a remote location makes use of a hand-held unit  102  to make a phone call to the base unit  101 . The base unit  101  automatically answers the call after a certain number of ringing is detected. Via the transmitter-receiver units, the hand-held unit  102  sends access code signal to the base unit  101  to request Caller ID or directory data. The base unit  101  then send the requested Caller ID or directory data to the hand-held unit  102 . The hand-held unit  102  store that data into its own memory  124  to  126  according, for later display on the LCD  111  to the user. 
     In the foregoing description of the invention, a preferred embodiment and several additional features have been disclosed. The invention is not limited thereto, however, and encompasses a variety of other embodiments and alternatives within the skill of those working in the art.