Location registration system enabling a radio telephone set to automatically start location registration for use in a mobile radio telephone network

Abstract: A mobile radio telephone system has line connection units (34) connected on the one hand to a telephone network (30) and also by lines (35) to radio connection devices (33) which communicate by radio with radio telephone sets (32). Each line connection unit has a subscriber's file (46) identifying which radio telephone sets are located in which of several zones served by the line connection unit. For starting a location information registration operation to enter information concerning the mobile radio telephone sets into the subscriber's file, each radio telephone set is provided with a travel measuring unit (80). The radio telephone set produces a request signal for the location information registration when the travel amount measured exceeds a first threshold value. Alternatively, the radio telephone set resets the measuring unit when the travel amount measured exceeds a first threshold value and thereafter produces a request signal for the location information registration when the travel amount measured goes below a second threshold value smaller than the first threshold value. The radio connection devices broadcast location information signals, and each radio telephone set holds its location information registered in the subscriber's file. When the telephone set receives one of the location information signals which has a location information different from the location information it holds, the radio telephone set produces another request for registration of the different location information.

Description: The present invention relates to a mobile radio telephone network system and, in particular, to a location registration system for registering the location of a radio telephone set in the mobile telephone network system. A mobile telephone network system of the type described generally comprises a telephone line and a plurality of radio telephone sets. The radio telephone sets are movable or travel in an area which is divided into a predetermined number of zones. A plurality of radio connection devices, or radio communication devices, are assigned to the respective zones. Providing that all the radio telephone sets are alive, that is, capable of always carrying out communication, and are moving among the zones, some of the radio telephone sets can use the radio connection device assigned to the zone in which the radio telephone sets in question are present at a given time. Between the telephone line and the radio connection devices, a line connection unit or a line control unit is connected for controlling communication between the telephone line and the radio connection devices. In detail, the line connection unit connects the telephone line with a particular one of the radio connection devices assigned to a particular one of the zones in which a particular one of the radio telephone sets is present, in order to enable the particular radio telephone set to carry out communication with the telephone line through the particular radio connection device and the line connection unit. In order to enable the line connection unit to select the particular one among the radio connection devices, the line connection unit must hold location information therein which is indicative of the particular zone number of the particular radio connection device in which the particular radio telephone set is present. To this end, the mobile telephone network system has a location registration system. In a conventional location registration system, the line connection unit has a subscriber's file for storing a list of the telephone numbers or identification (ID) numbers of the radio telephone sets and the numbers of the zones in which those radio telephone sets are present. Each of the radio telephone sets has a key which is operated by the user of the radio telephone set. When the user operates the key of the particular radio telephone set, the radio telephone set transmits a location registration request signal. One or more of the radio connection devices receive the location registration request signal as one or more received request signals, respectively, and detect the electric field strength or level of the received request signals. That is, those one or more radio connection devices serve as receiving devices. The receiving devices form modified request signals by adding to the received request signal the electric field strength signal and the zone numbers assigned to those receiving devices, and transmit the modified request signals to the line connection unit. The line connection unit receives those modified request signals and compares the electric field strengths in the modified requests signals with one another. Then the line connection unit selects the one of the modified request signals which has the highest electric field strength and registers into the subscriber's file the zone number in that modified request signal, together with the telephone number of the particular radio telephone set. Thus, it is possible to renew the location information of the radio telephone sets registered in the subscriber's file in the line connection unit. However, it is impossible to renew the location information of the radio telephone sets in the subscriber's file, if the user does not operate the key in his radio telephone set when his telephone set travels. Japanese Laid-Open Patent Application JP-A-61 245 639 describes a mobile communication system with a position registration system, in which a standard cycle signal for position registration is periodically transmitted from the radio base station. On receipt of this, the telephone set sends a request for transmission of the position registration information. Simultaneously the telephone set starts to count the time and calculates, from the stored standard cycle time and the speed of travel of the set, a time interval for the next transmission of the position registration information. If the time elapse exceeds this time interval the set again sends a request for position registration information. Thus, congestion arising from many telephone sets making simultaneous requests for position registration information is avoided. Another Japanese Laid-open Patent Application JP-A-2 050 532 describes the use of a movement sensor in a mobile telephone set. A location registration operation is started when the telephone set begins to move sufficiently to cause a weight to come into contact with walls surrounding it. There is no measurement of the amount of travel. Finally, European Patent Specification EP-A-0 295 678 describes a system in which location registration is performed without keeping the power supplies of the telephone sets on continuously. This is achieved by the base station transmitting the identification (ID) number of its zone for a duration which is longer than the off duration of the power supplies of the telephone sets. A request for registration is issued when the zone ID number received by the telephone set differs from the zone ID number which it has held in its own memory. The invention is defined in the independent claims below, to which reference should now be made. Advantageous features of the invention are set forth in the appendant claims. Preferred embodiments are described in detail below with reference to the drawings. In these embodiments each radio telephone set is provided with a unit for measuring the amount of travel of the set. The radio telephone set produces a request signal for the location information registration, when the measured travel amount exceeds a first threshold value. Alternatively, the radio telephone set resets the measuring unit when the travel amount measured exceeds a first threshold value. Thereafter the radio telephone set produces a request signal for the location information registration when the measured travel amount does not exceed a second threshold value which is smaller than the first threshold value. The invention will now be described in more detail, by way of example, with reference to the drawings, in which:- Fig. 1 is a schematic diagram view of a mobile communication system; Fig. 2 is a block diagram view of a mobile communication system according to one embodiment of the present invention; Fig. 3 is a diagram illustrating the contents of a RAM in a line connection unit in Fig. 2; Fig. 4 is a diagram illustrating the contents of a RAM in a radio telephone set in Fig. 2; Fig. 5 is a view illustrating the control operation of a travel measuring unit by a set controller in Fig. 2; Fig. 6 is a flow chart illustrating a travel deciding operation of the set controller; Fig. 7 is a diagram illustrating a first location registration operation according to a first embodiment; Fig. 8 is a flow chart illustrating the operation of the set controller for the first location registration according to the first embodiment; Fig. 9 is a flow chart illustrating the operation of a device controller in Fig. 2 for the first location registration according to the first embodiment; Fig. 10 is a flow chart illustrating the operation of a unit controller in Fig. 2 for the first location registration according to the first embodiment; Fig. 11 is a diagram illustrating the operation of a RAM in the radio telephone set in Fig. 2 according to a second embodiment; Fig. 12 is a flow chart illustrating the operation of the device controller for transmission of a location announcement signal according to the second embodiment; Fig. 13 is a diagram view illustrating the relation between the reception of the location announcement signal and power saving in the radio telephone set; Fig. 14 is a diagram illustrating the relation between the reception field levels from each radio connection device and the operation of an announcement detection timer in the radio telephone set; Fig. 15 is a flow chart illustrating a location announcement signal deciding operation by the radio telephone set according to the second embodiment; Fig. 16 is a diagram illustrating the operation of a second location registration in the second embodiment; Fig. 17 is a flow chart illustrating the operation of the set controller for the second location registration; Fig. 18 is a flow chart illustrating the operation of the device controller for the second location registration; Fig. 19 is a flow chart illustrating the operation of the unit controller for the second location registration; and Fig. 20 is a flow chart illustrating the registration deciding operation of the set controller in the second embodiment. Generally speaking, a mobile telephone network system comprises a telephone network 30, a plurality of telephone lines 31 connected to the telephone network 30 and a plurality of radio telephone sets (RTS) 32 which 25 can travel or are movable in an area which is divided into a plurality of zones Zl to Zn. Different telephone numbers are assigned to the radio telephone sets 32 and different zone numbers are also assigned to the zones Z1 to Zn. One or more radio connection or communication devices (RCD) 33 are assigned to each zone Zl to Zn and carry out communication with radio telephone set or sets 32 which are currently present in the zone. The radio connection devices in one zone have the same zone number and different device numbers. One of the radio connection devices in one zone serves as a main control device. In the following description, each zone will be described as having a single radio connection device as the main control device, for simplification of the description. A line connection or communication unit (LCU) 34 is connected between the telephone lines 31 and the radio connection devices 33 for carrying out communication therebetween. The line connection unit 34 is connected to the telephone lines 31, and to the radio connection devices 33 through a plurality of connection lines 35. The line connection unit 34 is provided with a subscriber's file which has the telephone numbers of the radio telephone sets 32 and the zone numbers as registered zone numbers in which those radio telephone sets 32 are currently present. When a particular one of the radio telephone sets 32 is called by one of the telephone lines, the line connection unit 34 refers to the subscriber's file and connects the particular radio telephone set 32 through the corresponding one of the radio connection devices. However, the radio telephone sets are movable in the area. Therefore, it is necessary to renew the registered zone numbers of the radio telephone sets 32 in the subscriber's file in the line connection unit. The present invention is directed to a location registration system for registering the number of the zone in which each radio telephone set is present after it has travelled. Referring to Fig. 2, the line connection unit (LCU) 34 comprises a matrix switch 40, a plurality of primary interfaces 41 between respective telephone lines 31 and the matrix switch 40, and a plurality of secondary interfaces 42 between the matrix switch 40 and the respective connection lines 35. Each of the primary interfaces 41 is operable as an interface for use in connecting each of the telephone lines 31 to the matrix switch 40. Each of the secondary interfaces 42 is operable as another interface for use in connecting each of the connection lines 35 and the matrix switch 40. Each of the connection lines is a two-wire transmission line. A tone trunk 43 is connected to the primary interfaces 41, to the secondary interfaces 42, and to the matrix switch 40, for generating various tone 25 signals, such as a call tone signal and other tone signals. A unit controller 44 is connected to the primary interfaces 41, the secondary interfaces 42, the matrix switch 40, and the tone trunk 43. The unit controller 44 is formed of a CPU and is associated with a read only memory (ROM) 45 and a random access memory (RAM) 46. The ROM 45 contains various control programs, such as a communication control program and a first location registration program, and control data. The RAM 46 contains various data. Referring to Fig. 3, the RAM 46 contains a subscriber's file which comprises a registration area 50 and a candidate area 51. The registration area 50 comprises a telephone number column 52 and a location number column 53. In the telephone number column 52 and held the telephone numbers assigned to the radio telephone sets 32. In the location number column 53, the numbers of the zones in which the corresponding radio telephone sets are currently present are written as registered location numbers. The candidate area comprises a zone number column 54 and a level data column 55. In the zone number column 54 is written the zone number which is in a modified first registration request signal received during the first location registration operation. In the level data column 55 is written the reception field level which is in the modified first registration request signal received during the first location registration operation. Returning to Fig. 2, attention will be directed to one of the radio connection devices (RCD) that is illustrated at 33 in Fig. 2. The illustrated radio connection device 33 comprises a line interface 60 and a speech signal controller 61. The line interface 60 is connected to the connection line 35, the speech signal controller 61 and a control signal transceiver 62. The line interface 60 is operable as an interface for use in connecting the connection line 35 and the speech signal controller 61 for a speech signal. The line interface 60 is also operable as an interface for use in connecting the connection line 35 and the control signal transceiver 62 for a control signal. A radio transceiver 63 is connected to the speech signal controller 61 and the control signal transceiver 62 and provides one end of a multichannel access system for carrying out radio communication with one of the radio telephone sets 32 through a communication antenna 64. The multichannel access system comprises a control channel and a prescribed number of speech or other communication channels. The control and the communication channels are of different radio frequencies and are shared by the radio connection devices 33 and the radio telephone sets 32. The control channel is used for transmitting a control signal between the radio connection device 33 and one of the radio telephone sets 32. The location registration which is directed by the present system is carried out by use of the control channel. The radio connection device 33 further comprises a device controller 65 which is connected to the control signal transceiver 62 and the radio transceiver 63. The device controller 65 comprises a CPU and is associated with a read only memory (ROM) 66. The ROM 66 contains various control programs, such as the first location registration program and other programs, and various control data, including the zone number assigned to that radio connection device 33. It should be understood that each of the other radio connection devices has a structure similar to the illustrated radio connection device 33. One of the radio telephone sets (RTS) 32 is shown in Fig. 2. The illustrated radio telephone set 32 comprises a radio transceiver 70 forming the other end of the multichannel access system, for carrying out radio communication with one of the radio connection devices 33 through a set antenna 71. The radio transceiver 70 is similar to the radio transceiver 63 of the radio connection device 33 and is operable in the similar manner. A handset 72 is connected to the radio transceiver 70 through a speech processing circuit 73. A control signal transceiver 74 and a set controller 75 are also connected to the radio transceiver 70. The control signal transceiver 74 is 5 operable for use in connection between the radio transceiver 70 and the set controller 75 for the control signal. The set controller 75 is operable for use in control of the speech processing circuit 73, and the control signal transceiver 74. A dialing key 76 is connected to the set controller 75. The dialing key 76 generates a dialing signal representative of either one of other radio telephone sets or one of subscriber telephone sets (not shown) connected to the telephone network 30 to supply a dialing signal to the set controller 75. A registration start key 77 is also connected to the set controller 75. The registration start key 77 is for generating a start signal representative of start of the first location registration to the set controller 75. The set controller 75 is also formed of a CPU and is associated with a read only memory (ROM) 78 and a random access memory (RAM) 79. The ROM 78 memorizes various control programs such as a travel deciding program, a first location registration program and other programs, and various control data including the telephone number of the particular radio telephone set 32. Fig. 4 illustrates a portion of the control data in the ROM 78. The control data shown comprise the travel monitoring time, a first threshold value, and a second threshold value smaller than the first threshold value which are used in execution of the travel deciding program. The RAM 79 is for use in memorizing rewritable data, including the registered zone number, and the number of the zone in which the radio telephone set in question is present. A travel measuring unit 80 is connected to the set controller 75. The travel measuring unit 80 is operable for sensing movement of the own radio telephone set 32 to calculate the amount or distance of its travel. The calculated travel amount of the travel measuring unit 80 is periodically read out by the set controller 75 and is reset by the set controller 75. The travel measuring unit 80 is disposed separate from the telephone set 32 and is connected to the radio telephone set 32 through a connection terminal 81. It is needless to say that the travel measuring unit 80 may alternatively be mounted within the radio telephone set 32. As the travel measuring unit 80, a device is used which comprises an eccentric pendulum and a counter. The eccentric pendulum vibrates in response to motion of the unit, and the number of vibrations of the pendulum is counted by the counter. Thus, the count of the counter is representative of the amount of travel of the unit. An odometer or trip meter may be also used as the travel measuring unit. The radio telephone set 32 has a battery 82 as a power source therefor and a power switch 83 for switching on or off power supply to various portions within the radio telephone set 32. The radio telephone set 32 is also provided with a power saving circuit 85 for controlling the electric power level supplied. Referring to Figs. 5 and 6, a travel decision by the set controller 75 will be described below. The set controller 75 periodically monitors the travel measuring unit 80 according to the travel deciding program in the ROM 78, after the radio telephone set 32 starts at a time instant t 1 (Fig. 5) and continues to travel together with the travel measuring unit 80. The travel measuring unit 80 measures the travel amount. The travel amount is read out and compared with a first threshold value TH 1 (Figs. 4 and 5) by the set controller 75, as shown at step 100 in Fig. 6. When it is decided that the travel amount exceeds the first threshold value TH 1 as shown at t 2 in Fig. 5, the set controller 75 resets the travel measuring unit 80 at step 101 (Fig. 6) and starts a travel monitoring timer at step 102 (Fig. 6). In detail, the set controller 75 has a timer 86 (Fig. 2). The travel monitoring time (78 in Fig. 4) is set into the timer 86. Alternatively, the time value of the travel monitoring time is written in a memory area in the RAM 79 (Fig. 2) and is reduced by subtraction as the time elapses. The travel monitoring time value is pre-determined to be small relative to the time within which the travel measuring unit can measure travel of the radio telephone set. The travel monitoring time is, for example, 20 seconds. When the travel monitoring time elapses at step 103 (Fig. 6), the set controller 75 again reads out the travel amount from the travel measuring unit 80 and compares the travel amount with a second threshold value TH 2 (Figs. 4 and 5) at step 104 (Fig. 6). When the travel amount exceeds the second threshold value TH 2 as shown at t 3 in Fig. 5, the set controller 75 again resets the travel measuring unit 80. That is, the control step by the set controller 75 returns to step 101. Thus, a series of control steps 101-104 are repeated. When the travel amount is lower than the second threshold value TH 2 , the set controller 75 decides that the travel of the radio telephone set 32 has stopped, that is, it detects that travel has been completed. When the set controller 75 detects the travel completion, it starts an operation for executing the first location registration operation of the system. In the travel decision described above, steps 101-104 may be omitted. As a result, when it is decided that the travel amount exceeds the first threshold value TH1 at step 100, the step proceeds from 100 to 105 directly as shown by a dotted line in Fig. 6. Now, the first location registration operation will be described referring to Figs. 7-10, below. The set controller 75 produces a first registration request signal (step 106 in Fig. 8) which is then transmitted through the control signal transceiver 74 and the radio transceiver 70 (Fig. 2) as shown at SQ 1 in Fig. 7. The first registration request signal comprises a preamble, a synchronizing signal and the sets own telephone number. The first registration request signal is received at one or more radio connection devices 33 in one or more zones Z 1 -Z n . In Fig. 7, radio connection devices in two zones Z 1 and Z 2 are presumed to receive the first registration request signal. Referring to Fig. 2, in each of the radio connection devices 33, the first registration request signal is received at the radio transceiver 63 through antenna 64 and is supplied to the device controller 65 through the control signal transceiver 62. The radio transceiver 63 detects the electric field strength of the first registration request signal as the reception field level signal. The reception field level signal is supplied to the device controller 65. Referring to Fig. 9, the device controller 65 receives the first registration request signal at step 107 and then produces a modified first registration request signal by adding to it the reception field level signal and the zone number at step 108. The modified first registration request signal is transmitted, as shown at SQ 2 in Fig. 7, to the line connection unit 34 through the control signal transceiver 62, the line interface 60, and the connection line 35 (Fig. 2). In Fig. 7, the radio connection device 33 in zone Z 1 transmits the modified first registration request signal earlier than the radio connection device 33 in zone Z 2 . In the line connection unit 34, the modified first registration request signal is supplied to the unit controller 44 through the secondary interface 42. Referring to Fig. 10, when the unit controller 44 receives the modified registration request signal at step 109 as an earlier modified first registration request signal, it starts an operation according to the first location registration program in the ROM 45. Then, the unit controller 44 writes the zone number and the reception field level signal in the earlier modified first registration request signal into the candidate area (46 in Fig. 3) corresponding to the telephone number in the earlier modified first registration request signal at step 110. Then, the unit controller 44 starts a request waiting timer at step 111 as shown at SQ 3 in Fig. 7. The ROM 45 has a request waiting time value as one of the control data. The request waiting time value is set to a timer as shown at 47 in Fig. 2. Alternatively, the request waiting time value is written into an area in the RAM 46. The unit controller 44 a-waits another reception of the modified registration request signal until lapse of the request waiting time is decided as shown at step 112. On the reception of another modified first registration request signal at step 113 as a later modified first registration request signal, the field level signal in the later modified first registration request signal is compared with the field level signal in the candidate area 51 at step 114. When the former is larger than the latter, the unit controller 44 renews the candidate area 51 by the zone number and the field level signal in the later modified first registration request signal on the other reception, at step 115. Then, the unit controller 44 produces a registration end signal at step 116. The registration end signal is transmitted to the one of the radio connection devices 33 which transmitted the earlier modified first registration request signal. In the example shown in Fig. 7, the registration end signal is transmitted to the radio connection device 33 in the zone Z 1 as shown at SQ 4 . If the field level signal in the later modified first registration request signal is equal to or smaller 0 than that in the candidate area 51 at step 114, the registration end signal is also produced at step 116 and is transmitted to the radio connection device 33 which transmitted the later modified first registration request signal. When lapse of the request waiting time is decided at step 112, the unit controller 44 produces a registration complete signal at step 117. The registration complete signal is transmitted through the secondary interface 42 to the radio connection device which has the zone number written in the candidate area 51. In the example shown in Fig. 7, the registration complete signal is transmitted to the radio connection device 33 of the zone Z 2 as shown at SQ 5 . Returning to Fig. 9, the device controller 65 a-waits reception of the registration end signal and the registration complete signal at steps 118 and 119 after producing the modified first registration request signal at step 108. When the device controller 65 receives the registration end signal through the line interface 60 and the control signal transceiver 62 (Fig. 2), the device controller 65 stops the operation for the first location registration. In the example shown in Fig. 7, the device controller 65 of the radio connection device 33 in the zone Z 1 stops operation. When the device controller 65 receives the registration complete signal, it produces a modified registration complete signal at step 120 which is transmitted through the control signal transceiver 62, the radio transceiver 63 and the device antenna 64 to radio telephone sets 32, as shown at SQ 6 in Fig. 7. The modified registration complete signal has the zone number of the radio connection device which transmits the modified registration complete signal, and the telephone number of the radio telephone set 32 which transmitted the first registration request signal. Returning to Fig. 8, the set controller 75 a-waits reception of the modified registration complete signal at step 121 after producing the first registration request signal. When the set controller 75 receives the modified registration complete signal having its own telephone number, it writes the zone number in the modified registration complete signal into the RAM 79 as the registered zone number at step 122. Then, the set controller produces a confirmation signal having the registered zone number and its own telephone number at step 123. The confirmation signal is transmitted to the radio connection devices 33 through the control signal transceiver 74, the radio transceiver 70 and the antenna 71 as shown at SQ 7 in Fig. 7. Returning to Fig. 9, the device controller 65 a-waits the confirmation signal at step 124 after producing the modified registration complete signal at step 120. When the device controller 65 receives the confirmation signal having its own zone number through the device antenna 64, the radio transceiver 63 and the control signal transceiver 62, it repeats the signal as the modified confirmation signal at step 125. The modified confirmation signal is transmitted to the line connection unit 34 as shown at SQ 8 in Fig. 7. Returning to Fig. 10, the unit controller 44 a-waits reception of the modified confirmation signal at step 126 after producing the registration complete signal at step 117. On reception of the modified confirmation signal, the unit controller 44 compares the zone number in the modified confirmation signal with the zone number in the candidate area 51 (Fig. 3). After the unit controller 44 confirms that then are consistent with each other at step 127, it renews the location number in the registration area 50 by the zone number in the candidate area 51 at step 128. Thus, the first location registration is completely finished. The first location registration can also be started by manual operation of key 77 (Fig. 2) as shown at step 129 in Fig. 8. Now, description will be made to the location registration system according to the second embodiment. The second embodiment is also applicable in the similar mobile radio telephone network system as shown in Fig. 2. Accordingly, the second embodiment is also described in connection with Fig. 2 for the purpose of simplification. However, it should be noted that control operation of the unit controller 44, the device controller 65 and the set controller 75 is different from the first embodiment, as will be understood with the description proceeding. Further, the RAM 79 in the radio telephone set 32 is also different from that in the first embodiment. Referring to Fig. 11, the RAM 79 comprises a registration file 130 and a candidate file 131. The registration file 130 is for memorizing a zone number as the registered zone number, a field level indicative of the electrical field strength of a signal received at the radio telephone set 32, and "Present" or "Wait" indicative of the reception status of the radio telephone set 32. The candidate file 131 is also for memorizing a zone number, a field level and a reception status which are similar to those in the registration file 130 but are as yet candidates for being registered ones. The unit controller 44 produces an announcing signal at predetermined time intervals. The time interval is memorized in the ROM 45 as one of the control data. The time interval is, for example, five (5) minutes. The announcing signal is supplied to all of the radio connection devices 33. Referring to Fig. 12, when the device controller 65 in the radio connection device 33 receives the announcing signal at step 132, it produces a location announcement signal at step 133. The location announcement signal has the zone number which is assigned to the particular radio connection device 33. The location announcement signal is repeatedly transmitted from the device antenna 64 in the zone, for example, five (5) times as shown at step 134. Referring to Fig. 13, the power saving circuit 85 (Fig. 2) controls the power level supplied from the battery 82 to the various portions in the radio telephone set 32 during an ON time period of the power switch 83. In detail, the power saving circuit 85 is active for a predetermined time duration and is inactive for another predetermined time duration. The total time duration of the active and the inactive time durations is called the power saving period which is usually selected to be 0.3 to 2 seconds. A ratio of the inactive or OFF duration to the active or ON duration is selected for example to be 1 : 3. During the inactive duration, the power level supplied from the battery 82 to the various portions of the radio telephone set 32 is the maximum. That is, the various portions are supplied with the power at a sufficient level and is active. On the other hand, during the active duration of the power saving circuit 85, the minimum power only is supplied to the various portions. Therefore, various portions are almost inactive. Thus, the power consumption of the battery 82 can be maintained low. The power saving circuit 85 is stopped or made inactive under control of the set controller 75 when the maximum power is desired for carrying out the telephone communication and other control operation. In order to make the radio telephone set 32 reliably receive the location announcement signal during the power saving period, the radio connection device 33 transmits the location announcement signal repeatedly for a time period which is larger than the power saving period by a predetermined short time α. Accordingly, at least one of the repeated location announcement signals is received at the radio telephone set 32 during the inactive or OFF duration of the power saving circuit 85. Referring to Figs. 14 and 15, description will be made as to processing the location announcement signal by the set controller 75. It is assumed in Fig. 14 that the radio telephone set 32 receives the location announcement signal from the radio connection device 33 in the zone Z 1 , repeatedly as shown at t001 - t005 and also receives the location announcement signal from the radio connection device 33 in the zone Z 2 repeatedly as shown at t101 - t104. The electric field level of the received signal is illustrated by the length of each arrow. Referring to Fig. 15, the set controller 75 sets an announcement detection timer at step 135 when the power switch 83 (Fig. 2) is turned on. In detail, the ROM 78 (Fig. 2) has an announcement detection time value. The set controller 75 sets the announcement detection time value in the timer 86 (Fig. 2). The timer 86 operates even during the active duration of the power saving circuit 85. When the announcement detection timer counts up the announcement detection time value, the announcement detection timer is again set. Thus, the announcement detection timer is repeatedly set as shown at t201 to t204 in Fig. 14. The announcement detection time value should be selected to be longer than the repeating period of the location announcement signal, for example, six minutes. After step 135, the set controller 75 a-waits reception of the location announcement signal at step 136. When the set controller 75 detects the reception of the location announcement signal, for example, from the radio connection device 33 in the zone Z 1 , at t001 as shown in Fig. 14, the set controller 75 compares the zone number in the location announcement signal with the zone number in the registration file 130 (Fig. 11) at step 137. When they are not consistent with each other, the set controller 75 writes the zone number in the location announcement signal as the candidate zone number, the field level signal of the location announcement signal as the candidate field level, and "Present" as the reception status, respectively, into 5 the candidate file 131 (Fig. 11) at step 138. The field level signal is detected at the radio transcriber 70 (Fig. 2) and is supplied to the set controller 75. On the other hand, if the zone number of the location announcement signal is coincident with the zone 0 number in the registration file 130, the set controller 75 rewrites the field level in the registration file 130 by the field level of the location announcement signal and writes "Present" as the reception status in the registration file 130 at step 139. The set controller 75 further resets the travel measuring unit 80 at step 139. Thereafter, when the announcement detection timer is still in operation at step 140, the set controller 75 again executes the operation of steps 136-140. During the operation, the set controller 75 receives the location announcement signal from the zone Z 2 at the time t101 shown in Fig. 14. When the announcement detection timer counts up the announcement detection time value at step 140, the set controller 75 accesses the registration file 130 (Fig. 11) at step 141. When "Present" is held as the reception status in the registration file 130, the set controller 75 writes "Wait" as the reception status into both of the registration and the candidate files 130 and 131 at step 142. Thereafter, the set controller 75 returns to the step 135. When "Present" is not held as the reception status in the registration file 130, the set controller 75 accesses the candidate file 131 at step 143. When "Present" is not held as the reception status in the candidate file 131, the set controller 75 returns to step 135. When "Present" is held as the reception status in the candidate file 131, the set controller 75 starts an operation for a second location registration at step 145. Now, description will be made as regards the second location registration referring to Figs. 16-19. The set controller 75 reads out the second location registration program from the ROM 78 and executes the program after step 145 in Fig. 15. Referring to Fig. 17, the set controller 75 produces a second registration request signal which has the telephone number assigned to the radio telephone set and the candidate zone number in the candidate file 131, at step 146. The second registration request signal is radiated from the antenna 71 through the control signal transceiver 74 and the radio transceiver 70, as shown at SQ 10 in Fig. 16. Referring to Fig. 18, when the radio connection device 33 receives the second registration request signal at step 147 and when the device controller 65 decides that the candidate zone number in the second registration request signal is equal to the zone number assigned to the radio connection device, at step 148, the device controller 65 repeats the second registration request signal and transmits it to the line connection unit 34 as a modified second registration request signal at step 149 and as shown at SQ 11 in Fig. 16. Referring to Fig. 19, when the unit controller 44 receives the modified second registration request signal at step 150, the unit controller 44 renews the location number in the registration area 53 (Fig. 3) by the candidate zone number in the modified second registration request signal at step 151. Thus, the second location registration for the line connection unit 34 is completed. Then, the unit controller 44 produces a registration complete signal at step 152. The registration complete signal has the telephone number and the zone number equal to those in the modified second registration request signal, and is sent back to the radio connection device 33 as shown at SQ 12 in Fig. 16. Referring to Fig. 18, when the device controller 65 detects the registration complete signal which has its own zone number at step 153, it repeats the registration complete signal as a modified registration complete signal at step 154. The modified registration complete signal is radiated from the device antenna 64 through the control signal transceiver 62 and the radio transceiver 63 as shown at SQ 13 in Fig. 16. Returning to Fig. 17, the set controller 75 receives the modified registration complete signal which has its own telephone number at step 155, and it renews the contents in the registration file 130 (Fig. 11) by the content in the candidate file 131 (Fig. 11) at step 156. The set controller 75 carries out the travel decision in Fig. 6 in addition to the location announcement signal processing in Fig. 15. When the travel is decided to be complete at step 105 in Fig. 6, the set controller 75 starts an operation for selecting one of the first and the second location registration programs. Referring to Fig. 20, the set controller 75 accesses the registration file 130 (Fig. 11) in the RAM 79 after the step 105 in Fig. 6. When "Present" is held as the reception status in the registration file 130 at step 157, the set controller 75 ends the selecting operation. On the other hand, when "Present" is not held in the registration file 130, the set controller accesses the candidate file 131 (Fig. 11). When "Present" is held as the reception status in the candidate file 131 at step 158, the set controller 75 starts the second location registration at step 159. Then, the second location registration is carried out as described above in connection with Figs. 16-19. On the other hand, when "Present" is not held in the candidate file 131 at step 158, the set controller 75 starts the first location registration at step 160. Then, the first location registration is 5 carried out as described above in connection with Figs. 7-10.

Claims: A location registration system for carrying out the registration of location information of each of a plurality of movable radio telephone sets (32) in a mobile telephone network system into a subscriber's file of a line connection unit (34) through a radio connection device (33) connected to the line connection unit (34), the system comprising: travel amount measuring means (80) associated with each of said radio telephone sets (32) for measuring the amount of travel of each radio telephone set (32) ; and each of said radio telephone sets (32) comprising: monitoring means (75) coupled with said travel amount measuring means (80) for monitoring the travel amount in said travel amount measuring means as a monitored travel amount; and registration starting means (75) coupled with said monitoring means and responsive to start signals for starting said registration of location information; characterized by: travel completion detecting means (75) coupled between said monitoring means and said registration starting means for detecting completion of the travel of each radio telephone set to produce said start signals. A location registration system as claimed in claim 1, wherein each of said radio telephone sets (32) further comprises holding means (78) for holding a threshold value (TM1), and said travel completion detecting means (75) is further coupled with said holding means (78) and decides said completion of the travel when said monitored travel amount exceeds said threshold value. A location registration system as claimed in claim 1, wherein each of said radio telephone sets (32) further comprises: first holding means (78) for holding a first threshold value (TM1); second holding means (78) for holding a second threshold value (TM2) smaller than said first threshold value (TM1); timer means (86) having a predetermined operable time period after start; and resetting and starting means (78) coupled with said first holding means (78), said monitoring means (75), said travel amount measuring means (80), and said timer means (86) for resetting said travel amount measuring means (80) and starting said timer means (86) when said monitored travel amount exceeds said first threshold value; said monitoring means (78) being further coupled with said timer means (86) and monitoring said travel amount measuring means (80) to produce a monitored value as said monitored travel amount when said timer means (86) stops its operation after start; and said travel completion detecting means (75) being further coupled with said second holding means (78) and detecting said completion of the travel when said monitored value is smaller than said second threshold value. A location registration system as claimed in claim 3, wherein said resetting and starting means (78) further resets said travel amount measuring means (80) and starts said timer means (86) when said monitored value exceeds said second threshold value. A location registration system as claimed in claim 1, wherein said travel amount measuring means (80) comprises an eccentric pendulum which swings in response to motion due to the travel of each radio telephone set and a counter for counting the number of swings as a count number, said count number representing said travel amount. A location registration system as claimed in claim 1, wherein said travel amount measuring means (80) is a trip meter. A location registration system for carrying out the registration of location information of each of a plurality of movable radio telephone sets (32) into a subscriber's file of a line connection unit (34) through radio connection device (33) connected to the line connection unit (34) in a mobile telephone network system, the first operation for said registration being started in response to a first start signal caused in each of the movable telephone sets (32), wherein each of said radio connection devices (32) comprises means (68) for transmitting an individual location announcement signal having an individual zone number, and each of said radio telephone sets (32) comprises: a first memory file (79, 130) for memorizing a first status signal and first location information having a first zone number; a second memory file (79, 101) for memorizing a second status signal and second location information having a second zone number; receiving means (75) for receiving said individual location announcement signal as a particular location announcement signal having said individual zone number as a particular zone number; comparing means (75) coupled with said first memory file (130) and said receiving means (75) for comparing said first zone number with said particular zone number, said comparing means producing a coincident signal when said first zone number is coincident with said particular zone number, said comparing means producing an error signal when said first zone number is different from said particular zone number; first writing means (75) coupled with said comparing means and said first memory file (130) responsive to said coincident signal for writing particular status information in said first memory file as said first status signal; second writing means (75) coupled with said comparing means and said second memory file (131) responsive to said error signal for writing said particular zone number and said particular status information in said second memory file (131) as said second zone number and said second status signal, respectively; first reading means (75) coupled with said first memory file and responsive to a first reading signal caused in the telephone set for reading (step 191) said first status signal in said first memory file to produce a first access signal when said first status signal is not indicative of said particular status information; second reading means (75) coupled with said first reading (78) means and said second memory file (131) responsive to said first access signal for reading (STEP 143) said second status signal in said second memory file (131) to produce said first start signal when said second status signal is indicative of said particular status information; and first starting means (75) coupled with said second reading means (75) responsive to said first start signal for starting said first operation for said registration of location information; wherein a second operation for registration is started in response to a second start signal caused in the telephone set (32), by provision of: travel amount measuring means (80) associated with each of said radio telephone sets (32) for measuring a travel amount of each radio telephone set (32); each of said radio telephone sets (32) comprising: monitoring means (75) coupled with said travel amount measuring means (80) for monitoring the travel amount in said travel amount measuring means (80) as a monitored travel amount; travel completion detecting means (75) coupled with said monitoring means for detecting, from said monitored travel amount, completion of the travel of each radio telephone set (32) to produce a second reading signal; said first reading means (75) further coupled with said detecting means (75) and reading said first status signal in said first memory file (130) responsive to said second reading signal to produce a second access signal when said first status signal is not indicative of said particular status information; said second reading means (75) reading said second status signal in said second memory file (131) responsive to said second access signal to produce said second start signal when said second status signal is not indicative of said particular status information, said second reading means (78) producing said first start signal when said second status signal is indicative of said particular status information; and second starting means (75) coupled with said second reading means (75) responsive to said second start signal for starting said second operation for said registration of location information. A location registration system as claimed in claim 7, wherein each of said radio telephone sets (32) further comprises: timer means (86) coupled with said receiving means (75) and being set when said receiving means (75) receives the particular location announcement signal said timer means (86) being in operation for a predetermined time duration after being set; and signal generating means (75) coupled to said timer means (86) and generating said first reading signal when said timer means (88) becomes out of operation due to elapse of the predetermined time duration after being set. A location registration method for carrying out the registration of location information of each of a plurality of movable radio telephone sets, the method comprising: measuring the amount of travel of each radio telephone set; monitoring the travel amount as a monitored travel amount; and starting said registration of location information in response to start signals; characterized by: detecting completion of the travel of each radio telephone set to produce said start signals.

Inventors: MOMMA KOHJI, NAGASHIMA NORIAKI, MOMMA, KOHJI, NAGASHIMA, NORIAKI, NAGASHIMA, NORIAKI, C/O NEC CORPORATION
Applicants: NIPPON ELECTRIC CO, NIPPON TELEGRAPH & TELEPHONE, NEC CORPORATION, NIPPON TELEGRAPH AND TELEPHONE CORPORATION, NTT MOBILE COMMUNICATIONS NETWORK INC.
Application year: 1991
Main classification: H04Q7
IPC codes: H04W60