JPH08163641A - Relief system for call at power failure time - Google Patents

Abstract

PURPOSE: To reduce the size, weight, and cost of the system for relieving a call which is being made with a mobile station at the time of the power failure of a base station by detecting the power failure time from the occurrence of the power failure to its recovery and continuing the call by using a radio signal if the call is already made with the mobile station at the time of the power failure. CONSTITUTION: If the power failure of the base station 2 occurs, a power source hit monitoring means 26 detects it and at the same time, a storage holding means 25 holds the contents of an opposite exchange speaking state managing means 23, a radio state managing means 24, and an information storage means 27. Further, the power source hit monitoring means 26 starts clocking the power failure time. When the base station recovers from the power failure, the power source hit monitoring means 26 detects the power source recovery and power failure time. The whether or not there is a mobile equipment 1 in a speaking state is confirmed and call continuance data in the information storage means 27 and the power failure continuance time are compared with each other; when the power failure continuance time is shorter than call continuance time and there is the mobile equipment in the calling state, a synchronizing signal is sent out to the mobile equipment to restart the call.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile communication system in which a plurality of base stations connected to an exchange by cables wirelessly communicate with mobile stations within the communication service area of the base station, and more particularly to the base station. The present invention relates to a call relief system for a call in progress with a mobile station when a station power failure occurs.

[0002]

2. Description of the Related Art In consideration of the importance of communication, a conventional base station device of a mobile communication system is designed so that the device can be operated for a certain fixed time (several hours) even if a power failure occurs. In addition, the commercial power source is backed up with a storage battery.

[0003]

This backup battery for the commercial power supply requires a considerably large current capacity because it is necessary to compensate for the current consumed by the base station device for several hours. There is a problem of increasing the volume and cost of the device.

On the other hand, in recent years, in a microcell type mobile communication system such as a personal handyphone system (PHS), the service area (cell) covered by one radio base station is compared with that of a car phone or a mobile phone system. Since it is very small, it is necessary to install the base station on a public telephone box, a telephone pole on the road, a road sign, etc. There is a strong need for downsizing / lightening, which conflicts with the measures against blackouts. The present invention was created in view of the above problems, and an object thereof is to reduce the size, weight, and cost of a system for relieving a call during a call with a mobile station during a power outage of a base station. And to simplify the installation work.

[0005]

The basic configuration of the present invention for achieving this object is shown in the principle diagram of FIG. A system for relieving a call during a call with a mobile station at the time of a power outage of a base station that is connected to an exchange and wirelessly communicates with the mobile station, and detects the power outage time from the occurrence of the power outage to the restoration of the base station. Means for determining whether or not the power outage time is within a specified time, and if the power outage time is within the specified time and during a call with the mobile station before the power outage, the call during the call is continued. And means for performing processing using a radio signal. In FIG. 1, reference numeral 1 is a mobile station, and this mobile station 1 is configured to include base station information transmitting / receiving means 11, base station transmission information storage means 12 and mobile station control means 13 described below. .

The base station information transmitting / receiving means 11 of the mobile station 1 is
Receives various system information such as carrier number, base station number, wireless line information, regulation information transmitted by base station 2, and transmits / receives control data and voice data related to call control by wireless signal with base station 2. It is a thing. The base station transmission information storage means 12 stores various system information transmitted by the base station 2, and the mobile station control means 13 controls the entire mobile station 1.

Reference numeral 2 denotes a base station. This base station 2 has a mobile station information transmission / reception means 21, a switch exchange information transmission / reception means 22, an inter-exchange call state management means 23, a radio state management means 24 and a memory which will be described below. It comprises a holding means 25, a power interruption monitoring means 26, and an information storage means 27.

The mobile station information transmitting / receiving means 21 of the base station 2 is
The mobile station 1 transmits and receives call control data and voice data to and from the mobile station by radio signals, and the exchange information transmitting / receiving means 22 transmits and receives call control data and voice data to and from the exchange 3. It is a thing. The call status management means 23 between the exchanges manages the status of each communication path provided between the exchange 3 and the base station 2 (vacant, in use, in trouble, restricted, etc.).

The radio status management means 24 manages the status of available frequencies / available slots of the base station 2 (used by another base station, used by its own base station, etc.). The memory holding means 25 stores and holds the contents of the communication state management means 23 between the exchanges, the wireless state management means 24, and the information storage means 27 when the power supply to the base station 2 is stopped. Power interruption monitoring means
26 detects the stop and resumption of power supply to the base station 2 and measures and monitors the power failure time. Information storage means 27
Is for storing the time to recover the call until recovery when a power failure or loss of synchronization with the mobile station 1 occurs in the communication state with the mobile station 1.

Reference numeral 3 is an exchange, and the exchange 3 is composed of base station information transmitting / receiving means 31, base station communication state management means 32 and base station operating state management means 33, which will be described below. The base station information transmitting / receiving means 31 of the exchange 3 is the base station 2
Alternatively, it transmits and receives call control data and voice data to and from the mobile station 1 via the base station, and each base station call state management means 32 can use each base station 2 accommodated in the exchange 3. It manages the usage status of various communication paths. Then, each base station operating state management means 33 monitors the operating state of each base station 2 accommodated in the exchange 3.

[0011]

In the present invention, when the call holding duration data is input to the exchange 3 from the maintenance table or the like, the data is stored in each base station operation state management means 33 of the exchange 3 and at the same time to the base station. Each base station 2 is notified via the station information transmitting / receiving means 31. The base station 2 receives the call holding duration data through the exchange information transmitting / receiving means 22, and the information storing means 27
The information is stored in the mobile station 1 and is sent to the mobile station 1 via the mobile station information transmitting / receiving means 21 as one of the system information.
The mobile station 1 receives the system information reported by the base station 2 via the base station information transmission / reception means 11 and stores it in the information storage means 12.

When a power failure occurs in the base station 2 and the power supply to the base station is stopped, it is detected by the power interruption monitor means 26, and at the same time, by the memory holding means 25, the inter-exchange communication state management means 23, the radio State management means 24, information storage means 27
The content of is retained. Further, the power supply interruption monitoring means 26 starts counting the power failure time from the occurrence of the power failure.

When the power failure of the base station 2 is restored, the power interruption monitoring means 26 detects the power restoration and the power failure time. From this power failure time, the communication path state management means between the exchanges
23, the radio condition management means 24 is read, and the mobile device 1 in the call condition
If there is a mobile device that is in the power outage duration or within the call duration time and there is a call in progress, check the presence or absence of the call and compare the call duration data in the information storage means 27 with the power outage duration. The mobile station sends a sync signal to the mobile station to establish synchronization.
Resume the call with 1.

[0014] Further, by transmitting to the exchange 3 the occurrence / recovery of the power outage, the power outage time, and the rescue / non-rescue of the call during the call at the time of the power outage, the maintenance person is notified of the system operation status information. .

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS.
This will be described in detail with reference to FIGS. 4 and 5. The mobile telephone system according to this embodiment generally has a configuration as shown in FIG. In FIG. 5, the exchange 3 synchronizes with a plurality of wired base stations CSa to CSd at the time of system initialization such as power-on, radio channel information, system information, call information, and synchronization with mobile stations. The notification information including the call holding timing information at the time of disconnection is transmitted, and the 5 ms frame clock and the transmission / reception timing clock for determining the absolute position of the basic frame in the wireless section are supplied.
The exchange 3 is also connected to other communication lines and external lines. Mobile stations PSa to PSd can communicate with other mobile stations and other communication lines by communicating with exchange 3 through base station CS whose service area is the location of each mobile station. There is. 2 to 4 are block diagrams showing the configuration of an embodiment of the present invention. FIG. 2 is an embodiment of the mobile station PS, FIG. 3 is an embodiment of the base station CS, and FIG. 4 is an embodiment of the exchange 3. Shows the configuration of.

The mobile station PS shown in FIG. 2 has an antenna section 13, a radio section 14, a TDMA control section 15, an A / D, D / A conversion section 16, a microphone section 17, a speaker section 18, and a display control section 19 which will be described below. , Key input section 1
It consists of a, main controller 1b, and main memory 1c. Here, the radio unit 14 includes a modulation unit 14a, a demodulation unit 14b, a clock extraction unit 14c, and a reception level detection unit 14d.The modulation unit 14a modulates transmission data and the demodulation unit 14b demodulates reception data. The clock extraction unit 14c extracts a transmission / reception timing clock from the received data and supplies it to each unit constituting the mobile station PS as a timing clock. The reception level detector 14d
The carrier sense for specifying the reception interference wave and the reception electric field strength measurement during communication are performed. The TDMA control unit 15 receives an instruction from the main control unit 1b between the specific base station CS and
It is for performing frame generation and disassembly of control information such as link allocation request and rejection, and call data, which are transmitted and received by TDMA burst signals in the wireless section. The microphone part 17
Converts the voice of the operator of the mobile station into an analog electric signal,
The speaker unit 18 performs voice conversion of an analog electric signal of the other party who talks with the operator of the mobile station and generation of a warning signal such as a ring tone. The key input unit 1a is used by the operator of the mobile station to input to the mobile station for dialing, calling, answering, etc. of the other party, and the display unit 19 is the dial input from the key input unit 1a. Numbers, incoming call display, mobile station status display such as during a call. The A / D, D / A converter 16 converts an analog voice signal into a digital code signal and a digital code signal into an analog voice signal. The main control unit 1b has an antenna 13 and a radio unit 14 which are base stations CS.
The control information received from the key input unit 1a, the key information input from the key input unit 1a, the received electric field strength data from the reception level detection unit 14d, and the like are analyzed, and each unit of the local station PS is controlled. The storage unit 1c is for temporarily storing control information received from the base station CS, state management information for controlling the own station PS, and call holding timing data received from the base station CS. The base station CS of FIG. 3 is transmitted / received as a TDMA burst signal in a wireless section according to an instruction from the antenna 26, a wireless unit 27 including a modulator 27a, a demodulator 27b, and a reception level detector 27c, and an instruction from the main controller 2b. TDMA control unit 28 that generates and decomposes various control information and call data frames, wired line control unit 2c that controls the exchange 3 and interface of call data, and exchange 3
A clock extraction unit 2d that extracts a transmission / reception timing clock from the received data from the device, a timing generation unit 2f that supplies the timing clock to each unit that configures the base station CS from the clock extraction unit 2d, a mobile station PS, and a switchboard. Communication between the main control unit 2b that controls each unit of the own base station CS from the control information received from 3 and the judgment result at the time of carrying out the carrier sense, the frequency and slot state available in the own base station, and the communication with the mobile station PS The storage unit 2e that stores the status, the call holding timing at the time of out-of-sync, the usage status of the telephone path to the exchange, the status management information for controlling the own base station, and the power supplied from the outside in the own base station CS The power supply unit 29 that converts the voltage to the voltage used by the power supply, and the power cut / recovery monitoring unit 2g that monitors the power supply voltage of its own base station,
It comprises a power supply backup unit 2h that backs up the power supply of the storage unit 2e when the power supply to its own base station is cut off. The exchange 3 shown in FIG. 4 has control carrier broadcast information to the base station CS, broadcast information transmission timing, call holding timing when synchronization is out of sync, base station number information for each base station, base station installation information, and accommodation in the exchange. Maintenance console communication that controls data transmission and reception between the maintenance console (MC) 3e that inputs station data necessary for the operation of the exchange including the mobile station PS number information and the maintenance console (MC) Control unit (IOC) 3a
And a basic frame clock, a data transmission / reception timing clock, a superframe start position clock, and a clock necessary for operating the network in the exchange from the broadcast information transmission timing information.
Master clock block (MCLK) 39 distributed to each component of 3
And the base station subscriber circuit (CSLC) 35, 36 for controlling the communication of voice data and control data with the base station CS, and the communication path with each subscriber circuit including the base station subscriber circuit (CSLC). Network (NW) 34 for setting and controlling a communication path of control data for setting and controlling the exchange processing between the subscriber circuit and the main control unit, and the exchange 3
The call processor (CPR) 37 that controls the call of the switchboard, the management processor (MPR) 38 that controls the status management of the entire switchboard, and the station data input from the maintenance console MC. Call status with each base station CS, call hold timing information when the base station is out of synchronization,
Each base station includes a main storage unit (MM: main memory) 3b that stores base station installation information that stores distance data to neighboring base stations.

The operation of transmitting the notification information between the exchange 3 having the above configuration and the base station CS will be described below. When the system is opened, the maintenance person sends to the exchange 3 shown in FIG. 4 the station data such as the mobile station number and the base station number of the mobile station PS accommodated in the exchange and the radio for the base station to transmit the control information. From the maintenance console (MC) 3e, enter channel information, system information, call information, regulation information and transmission interval, channel configuration, and call holding timing when synchronization is lost. The data input from the maintenance console (MC) 3e is used for the maintenance console communication controller (IOC) 3a.
It is notified to the management processor (MPR) 38 via the. The management processor (MPR) 38 obtains the transmission interval data from the above data, and the master clock unit (MC
K) 39, information on the wireless channel for transmitting control information,
Notifying the base station subscriber circuits (CSLC) 35, 36 of the network (NW) 34 accommodated in the exchange 3 together with system information, call information, channel configuration information of regulation information and control information. The master clock unit (MCK) 39 generates the transmission timing clock of the base station and the operation clock of the network (NW) 34 from the transmission interval data of the control information set by the management processor (MPR) 38, and Supply to each part. Base station subscriber circuits (CSLC) 35, 36 are
To each base station CS, wireless channel information for transmitting control information, system information, call information, regulation information, and call holding timing information when out of synchronization is transmitted. In addition to these data, a master frame clock (MCK) 39 is also supplied with a basic frame clock for determining the position of the basic frame in the wireless section, a transmit / receive timing clock, and a superframe start position timing clock. To do.

The base station CS of FIG. 3 sends the information transmitted from the exchange 3 through the wired line control unit 2c and the main control unit 2b.
Read at. Further, the wired line control unit 2c extracts the frame clock, the transmission / reception timing clock, and the superframe start position timing clock from the data supplied from the exchange 3, and the internal timing generation unit of the base station CS.
Supply to 2f. Based on the radio channel information received from the exchange 3, the main control unit 2b determines the transmission interval time of the control slot, the configuration of the basic frame length of the control slot, the number of channels of paging information accommodated in one basic frame, and the number of channels within one superframe. The TDMA control unit analyzes the number of basic frames to be accommodated.
Set the send data to 28. The base station CS performs carrier sensing before investigating the interference radio wave from another base station before starting the transmission of the control carrier to the mobile station PS. In the carrier sense, the electric field strength of the reception signal input from the antenna 26 to the reception level detecting unit 27c of the wireless unit 27 is measured. The main control unit 2b, after collecting the measurement information of the electric field strength only for the superframe time, judges whether or not it is possible to send the control carrier to the mobile station PS, from the judgment result judged at the timing of each transmission timing clock. Then, the transmission start of the broadcast information by the control carrier is set to the TDMA control unit 28. When the TDMA control unit 28 receives the notification information transmission instruction from the main control unit 2b, the timing generation unit
In synchronization with the transmission timing clock distributed from 2f,
Start sending broadcast information.

The mobile station PS shown in FIG. 2 performs the following standby processing when the power is turned on. When the power is turned on, the main control unit 1b sets the TDMA control unit 15 so as to be able to receive the broadcast information from all the base stations CS, and also activates the wireless unit 14. The TDMA control unit 15 takes in the broadcast information received via the demodulation unit 14b of the radio unit 14 and the reception level data measured by the reception level detection unit 14d at the timing of receiving the broadcast information, and the main control unit 1b Notify to. By performing the above operation for a certain period of time, the main control unit 1b receives the notification information transmitted by the base station CS around the area where the mobile station PS is located and measures the received electric field strength thereof. Of the received electric field strength measured during the reception period of this notification information, the maximum one is determined to be the base station CS closest to the mobile station PS,
The base station number of the closest base station CS is recognized from the received notification information, and the base station number is set in the TDMA control unit 15. Since the specific base station number is set, the TDMA control unit 15 shifts to an operation (standby operation) of receiving only the broadcast information broadcast by the specific base station CS. The out-of-sync call holding timing included in the notification information is stored in the out-of-sync call holding timing storage unit 1d in the storage unit 1c. After shifting to the standby operation, the operator of the mobile station PS inputs the telephone number of the calling party and the call request from the key input unit 1a of the mobile station PS so that the operator can talk. The main control unit 1b recognizes the call origination request and sets the data of the link establishment request information to the TDMA control unit 15 in order to send the link establishment request information to the base station CS, and activates the transmission. TDMA controller 15
The link establishment request data set to is input to the radio unit 14, modulated, and then sent out from the antenna 13. The link establishment request data transmitted from the mobile station PS of FIG.
It is input from the antenna 26 of the base station CS to the radio section 27, demodulated by the demodulation section 27c, and then input to the TDMA control section 28. TD
The MA control unit 28 notifies the main control unit 2b that data has been received from the mobile station PS. The main controller 2b analyzes the received data stored in the TDMA controller 28 and recognizes the reception of the link allocation request. The main control unit 2b reads the data of the communication path management portion between the exchanges and the wireless state management portion in the storage unit 2e, and determines whether there is a vacancy in the communication path between the exchanges or a newly assignable wireless connection. Determine if there are carrier slots. Then, if there is a space, the link allocation information is set in the TDMA control unit 28 and transmitted to the mobile station PS. The data for the management of the communication path between the exchanges can be updated when the call is made possible by the mobile station PS and when the call from the exchange 3 enables connection with the mobile station PS. In this case, the used slot is stored. The data update in the radio status management part is performed for each carrier sense determination result performed when the link allocation request from the mobile station PS is received, or for the carrier performed when the available slot in the base station CS is in the unused state. At the time of sensing and when shifting to a call with the mobile station PS, the call use slot or frequency is written.

The operation of holding a call at the time of power failure of the base station CS in the above case will be described below. When a power failure occurs in the base station CS, the power failure / recovery monitoring section 2g detects a decrease in the output voltage of the power supply section 29 of the base station CS and starts counting the power failure time. Further, the power supply backup unit 2h supplies a backup voltage to the storage unit 2e of the main control unit 2b of the base station CS, so that the data in the storage unit 2e is held. When the power failure of the base station CS is restored, the power supply unit 29
The power-off / recovery monitoring unit 2g detects that the output voltage of has been restored, and stops counting the power failure time. Main control unit
2b is a power-off / recovery monitoring unit that starts up when the power is turned on.
Read how long the power failure time measured by 2g was,
The call holding timing in the storage unit 2e is compared with the time stored in the storage unit 2e3. As a result, if the power failure time is within the call holding timing, the wireless state management unit in the storage unit 2e
2e1 and the inter-exchange call path management unit 2e2 are read and the mobile station number, radio frequency, wireless slot number used, and inter-exchange call slot number that were in communication before the power failure are set as data in the TDMA control unit 28. Then, the wireless unit 27 and the wired line control unit 2c are activated to perform the operation of establishing synchronization for continuing the call. If the power failure time is equal to or longer than the call holding timing, even if the mobile station PS is in a call state before the power failure, the call relief operation is not performed and the notification information transmission operation is performed. When the base station CS recovers from the power failure, the base station CS notifies the exchange 3 of the occurrence / recovery of the power failure and the relief / non-relief of the call during the call. Even if the synchronization with the base station CS is suddenly lost, the mobile station PS and the exchange 3 continue the synchronization establishing process for re-establishing the synchronization if the call holding timing is not reached. When the call holding timing is exceeded, the call release processing is performed. The power backup unit 2h of the base station CS is composed of a small secondary battery (button battery) and a capacitor (super capacitor). In addition, by configuring the storage unit 2e that stores various data processed by the main control unit 2b of the base station CS by a so-called EEPROM or flash memory that retains the stored contents even when the drive power supply is cut off, A configuration without the power backup unit 2h is also possible.

[0021]

As described above, according to the present invention, a base station device of a mobile station of a mobile telephone system is installed without a large capacity backup power supply as a countermeasure against a power failure in the base station. Can be configured, and the effects of miniaturization / light weight / cost reduction of the device and simplification of device installation can be obtained.

[Brief description of drawings]

FIG. 1 is a principle diagram showing a basic configuration of a call relief system when a power failure occurs according to the present invention.

FIG. 2 is a block diagram showing a circuit configuration of a mobile station according to an embodiment of the present invention.

FIG. 3 is a block diagram showing a circuit configuration of a base station according to an embodiment of the present invention.

FIG. 4 is a block diagram showing a circuit configuration of an exchange according to an embodiment of the present invention.

FIG. 5 is a diagram showing a general configuration of a mobile telephone system.

[Explanation of symbols]

1 is a mobile station PS, 2 is a base station CS, 3 is an exchange, 1a is a mobile station
1 key input section, 1b main control section, 1c storage section, 1d call holding timing storage section when synchronization is lost, 14 radio section of mobile station 1, 15 TDMA control section, 2b of base station 2 Main control part, 2d
Is a clock extraction unit, 2e is a storage unit, 2f is a timing generation unit, 2g is a power interruption / recovery monitoring unit, 2h is a power backup unit, 27 is a radio unit of the base station 2, 28 is a TDMA control unit, and 3a is a switch 3 Maintenance console communication controller IOC, 3b is main memory
MM, 3c is analog subscriber circuit LC, 3e is maintenance console M
C, 34 are networks NW in the exchange 3, 35, 36 are base station subscriber circuits CSLC, 37 is a call processing control unit, 38 is a main control unit MPR,
39 is a master clock block MCK.

Claims (5)

[Claims] 1. A system for relieving a call during a call with a mobile station at the time of a power failure of a base station which is connected to an exchange and wirelessly communicates with the mobile station, from the occurrence of the power failure to the restoration of the base station. Means for detecting the power outage time of the device, means for determining whether or not the power outage time is within a specified time, and if the power outage time is within the specified time and a call is in progress with the mobile station before the power outage, the call A call relieving system in the event of a power failure, characterized in that it comprises means for performing continuous processing of the inside call using a radio signal. 2. The base station further comprises means for notifying the mobile station of a rescue time for recovering a call during disconnection when a loss of synchronization with the mobile station occurs, to the mobile station by using a radio signal. The call relief system when a power failure occurs according to claim 1. 3. The call when a power failure occurs according to claim 1, wherein the base station includes means for changing a relief time for performing a call recovery operation from the outside (switch) when the power failure is restored. Relief system. 4. The power outage according to claim 1, wherein the base station has means for notifying the exchange of information on occurrence and recovery of power outage, relief of call during communication or non-relief. Call relief system. 5. A power supply by using a storage unit for storing various data processed by the main control unit of the base station as an EEPROM or a flash memory that retains the stored contents even when the drive power supply is cut off. The call relieving system in the event of a power failure according to claim 1, wherein the system has no backup unit.