Abstract:
A method of sending a short message to a receiver at a predetermined time in a digital mobile phone, which includes the steps of changing the operational mode of the mobile phone from a short message preparation mode to a multiply addressed sending mode, sequentially registering a series of phone numbers designating the receivers to receive the short message, sequentially sending the short message to the receivers according to the order of the registered phone numbers when a send signal is inputted, and setting the mobile phone to a standby mode when the short message has been sent to each of the receivers.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to a digital mobile phone and in particular, to a method of sending a short message in a digital mobile phone. 
     2. Description of the Related Art 
     Digital mobile phones are commonly provided with a short message service (SMS), which enables the user to send a short message constructed as a sequence of characters to another subscriber. The short message is displayed by the receiver as visual information composed of alphanumeric characters representing the sender&#39;s message and telephone number. The conventional SMS mobile phone may only send a short character message to a single subscriber. That is, it cannot simultaneously send the prepared message to several receivers, i.e., by a single key input at a predetermined time. Sending a prepared short message to multiple addressed receivers at a predetermined time may be additionally provided only by employing the system of the service provider. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide a method of sending a prepared short message to several receivers via a single key input at a predetermined time in a digital mobile phone. 
     According to an aspect of the present invention, a method of sending a short message to a plurality of receivers at a predetermined time in a digital mobile phone, includes the steps of: changing the operational mode of the mobile phone from a short message preparation mode to a scheduled sending mode, registering the predetermined time while in the scheduled sending mode, setting a scheduled sending function after registering the short message including the user&#39;s identifying information, and sending the registered message when the present time detected is equal to or exceeds the predetermined time. 
     According to another aspect of the present invention, a method of sending a short message to a plurality of receivers at a predetermined time in a digital mobile phone, includes the steps of: changing the operational mode of the mobile phone from a short message preparation mode to a multiply addressed sending mode, sequentially registering a series of phone numbers corresponding to the plurality of receivers, sequentially sending the short message to the plurality of receivers associated with the registered phone numbers by reading the series of phone numbers when a send signal is inputted, and setting the mobile phone to a standby state when the short message has been sent to each of said plurality of receivers. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a block diagram of a digital mobile phone with a character recognition means, which may provide a short message service (SMS) according to an embodiment of the present invention; 
     FIG. 2A is a flowchart illustrating a method for preparing a message upon entering a short message preparation mode according to an embodiment of the present invention: 
     FIG. 2B is a flowchart illustrating how a multiply addressed short message is transmitted according to an embodiment of the present invention; 
     FIG. 2C is a flowchart illustrating a method for registering scheduled times to send the short message according to an embodiment of the present invention; and 
     FIG. 2D is a flowchart illustrating a method for sending the short message at the scheduled times according to an embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 generally depicts, in block diagram form, the construction of a digital mobile phone in accordance with the invention. Referring to FIG. 1, the digital mobile phone is generally controlled by a one-chip microprocessor  10  according to a control program. A memory device  20  is operatively coupled to the microprocessor  10 , and includes ROM for storing the operational program required to control the phone, and RAM for temporarily storing the data generated during execution of the operational program. The RAM typically serves as a buffer. Also included in the memory device  20  is an electrically erasable and programmable ROM (EEPROM) to store optional data for the operational program. In the present embodiment, the EEPROM includes a subscriber phone number storage area for storing the phone numbers of the subscribers, and a scheduled time storage area for storing scheduled times. 
     Key input part  30  includes a plurality of alphanumeric keys, functional keys, and a message key for entering the short message service (SMS) mode. The key input part  30  generates key data applied to the microprocessor  10 , which controls a display  40  to display the key data in addition to information concerning the operational state of the digital mobile phone in icons and characters. A signal processor  60  converts the sounds inputted through a microphone MIC into digital signals and also converts digital signals into corresponding analog signals to be outputted through a speaker SPK. A radio frequency part (hereinafter referred to as RF part)  50  includes a duplexer  55  for separating the radio signals transmitted and received through an antenna ANT, a receiver  51  for demodulating the radio signals received through the antenna ANT into the base band signals applied to the signal processor  60 , and a transmitter  53  for modulating the signals from the signal processor  60  into the radio signals. The short message is modulated by the transmitter into the radio signal. 
     FIG. 2A is a flow diagram illustrating a method for preparing a short message upon entering the short message preparation mode. FIG. 2B is a flow diagram illustrating how a multiply addressed short message is transmitted. FIG. 2C is a flowchart illustrating the scheduled times to send the short message. FIG. 2D is a flowchart illustrating sending the short message at the scheduled times. Each figure will be described in greater detail below. 
     Referring initially to FIG. 2A, when the digital mobile phone is in a standby state in step  210 , upon depressing the message key of the key input part  30 , in step  211 , the short message service (SMS) menu is displayed in step  212 . The SMS menu displays the functional modes which include, for example, a message preparation mode and a message confirmation mode. Upon determining that the message preparation mode has been selected from the SMS menu in step  213 , a submenu of the message preparation mode is displayed in step  214 . Otherwise, if a mode other than the message preparation mode is selected at decision step  213 , a branch is taken to step  218  for performing one of the other modes displayed in the SMS menu, for example, the message confirmation mode. The submenu of the message preparation mode contains choices for editing, retrieving and composing a sentence. Step  215  is a decision step for determining if a method of editing has been selected by the user. If not, the process returns to step  214 , the display step. Otherwise, the process continues at step  216  describing methods for composing and editing a sentence. Then, it is determined whether a key input has been received to enter the multiply addressed sending mode, described below with reference to FIG.  2 D. 
     The method for transmitting a short message in a multiply addressed sending mode will now be described in connection with FIG.  2 B. The microprocessor  10  initializes the index of the subscriber phone number storage in step  221  (i.e., the index counter is initialized to zero). This step is performed in preparation for making a new index of the subscribers&#39; phone numbers newly inputted after deleting a previously set index of the subscribers&#39; phone numbers. Messages are sent in accordance with the order of the current index. For each message sent, a previously set phone number to which the message has been sent is deleted from the new sending index of the subscriber phone number storage, so that a new phone number may be stored for a next sending operation. In step  222 , it is determined whether a previously stored phone number is to be used for the sending of the message. If so, a search mode is started to search the stored phone numbers in step  224 . The retrieved phone number is stored in step  225  in a sending buffer “Temp” in step  226 . However, if it is determined in step  222  that the phone number previously stored is not to be used, the user may input the receiver&#39;s phone number in step  223 . Likewise, the receiver&#39;s phone number inputted by the user is stored into the sending buffer “Temp” in step  226 . If the user requires the input of an additional phone number in step  227 , in step  229 , the index of the subscriber phone number storage is increased by one (presently initialized to NULL) after storing the receiver&#39;s phone number into the sending index of the subscriber phone number storage. Then, the process returns to step  222  to store the additional phone number. However, if there is no demand for an additional phone number in step  227 , the process proceeds to step  228  to input the sender&#39;s phone number who is to receive the SMS response message in step  228 . 
     In step  230 , the message transmission rate is determined according to whether the message should be sent as speed mail, urgent mail or ordinary mail. The message is then sent in step  231 . The receiver&#39;s phone number is retrieved from the buffer “Temp” and stored into a given region of the EEPROM in step  232 , so that it may be reused later, for example, sending another message to the same receiver. In step  233 , it is determined whether the index of the subscriber phone number storage is zero. A zero index means that the message has been sent to all of the phone numbers stored. In step  233 , if it is determined that the index is zero, the sending of the message is terminated in step  234 . However, if the index of the subscriber phone number storage is not zero, the index is decreased by one in step  235  to return to step  231  to continue the sending of the message to the phone number associated with the decreased index. Namely, the buffer “Temp” is written with the phone number of the decreased index. 
     FIG. 2C is a flowchart illustrating the method for sending the SMS message. Referring to FIG. 2C, if the key input represents the ordinary sending mode instead of the multiply addressed sending mode as described in step  217  of FIG. 2A, the receiver&#39;s phone number is entered in step  240 . Thereafter, the message transmission rate is specified in step  241 . If the scheduled sending mode is not selected in step  242 , the message is sent in accordance with the conventional sending method, in step  244 . However, if the scheduled sending mode is selected in step  242 , the time scheduled to send the message is entered in step  243 . If the scheduled time entered is determined to be a past time in step  245 , the process returns to step  243 . Otherwise, if the scheduled time entered is determined to be a future time in step  245 , there are stored in step  246  the prepared message, receiver&#39;s phone number, sender&#39;s phone number and the scheduled time. In step  247 , the scheduled sending function is set to be further described with reference to FIG.  2 D. 
     With reference to FIG. 2D, the reference time is first set to the present time in step  250 . In step  251 , the microprocessor  10  enters the standby mode. If, in decision step  253 , it is determined that the scheduled sending function has been set, a reference time Time1 is set to the scheduled sending time in step  254 . If it is determined in step  255  that the present time is equal to or greater than the reference time, the message is sent in step  256 . Otherwise, the method remains in loop  255  until the present time is equal to or greater than the reference time. Then, the scheduled sending function is released in step  257 , deleting all the stored data in step  258 . Though not described in FIG. 2D, step  256  may be repeated when the sending of the message fails. 
     While the invention has been shown and described with reference to a certain preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.