JP3102760B2 - Out-of-service standby method for mobile communication - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce power consumption without delaying the time of transition from out-of-zone state to awaiting state so much. SOLUTION: When a mobile station is moved from an awaiting zone to outside the zone of a home mobile communication network to which that mobile station is belongs or a roam mobile communication network in which roaming is permitted, while intermittently turning on the power source of a reception system circuit of a radio unit, the controller of the mobile station intermittently executes a catch operation A for a control channel to be waited for in the home mobile communication network and a catching operation B for a control channel to be waited for in the roam mobile communication network. In this case, the catching operation A for the control channel to be waited for in the home mobile communication network is performed more frequently than the catching operation B for the control channel to be waited for in the roam mobile communication network and when the control channel is caught, the mobile station is changed to the waiting state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an out-of-service standby method for mobile communication, and more particularly, to a mobile station which is different from the home operator mobile communication network to which the mobile station is subscribed but roaming is permitted. The present invention relates to an out-of-service standby method for mobile communication that can be used in both roaming mobile communication networks.

[0002]

2. Description of the Related Art In recent years, call connection by a mobile phone, which has become very popular, is standardized (published by the Radio System Development Center, "Digital car telephone system standard".
(RCRSTD-27 formulated on April 30, 1991, and the revised versions of A to D) will be described as follows. A large number of reception carrier frequencies are allocated to mobile communication. In the case of many reception carriers of the three-channel multiplex TDMA system, a set of slots 2 and 5 of a reception frame is used by the mobile station to receive various control information from the base station. Form a control channel. The frequency of the main reception carrier in which the set of slots 2 and 5 of the reception frame is used as a control channel is called a perch frequency, and is used as a clue for searching for a standby control channel when the power is turned on or out of service area. I remember. A set of slots 2 and 5 of the received frame at the perch frequency is called a perch channel. After the power is turned on, the mobile station performs a perch channel scan and a standby channel selection operation to capture a standby control channel and enters a standby state (standby transition). First, the mobile communication network is tuned to each perch frequency in order to search for a perch channel whose reception level is equal to or higher than a specified value (perch channel scan). Next, in order of the reception level, tuning to the perch channel and starting standby are performed. A determination is made as to whether or not the condition is satisfied (the start condition will be described later). A perch channel when all the standby start conditions are satisfied (or another control channel when another control channel is specified in the control information) Is a standby control channel (standby channel selection operation). And
If necessary, it requests location registration from the mobile communication network. The mobile communication network responds that there is an incoming call through the paging channel (broadcasting channel) PCH among the standby control channels, and switches to the traffic channel (information channel) TCH designated by the single cell channel (individual cell channel) SCCH. Make a ringing tone.
A call path is set off-hook (incoming call). When the mobile station in the standby state goes off-hook, a call request is made after confirming that the SCCH is empty, and if there is a response, the call is switched to the TCH specified by the SCCH, a dial signal is transmitted, and a communication path is set. (Call). If the mobile station or the base station (on the network side) goes on-hook during a call, or if the reception level falls below a predetermined value, a call termination process is performed and the call stands by on the original standby control channel (call termination).

If the reception level from the base station in the serving zone falls below the standby degradation level and the reception level from the base station in the surrounding zone falls below the standby permission level during standby, it is determined that the mobile station has gone out of the mobile communication network. The mobile station acquires a new standby control channel (out-of-service standby).
Specifically, first, the perch frequency stored in the memory is scanned, the perch channel whose reception level is equal to or higher than a specified value is associated with the reception level, and stored as a selection channel (perch channel scan). Next, while tuning to the selection channel stored in the memory this time in descending order of the reception level, tuning, synchronization establishment, error detection / correction,
It detects the reception level and receives the broadcast channel (broadcast information channel) BCCH. And OSI (Op
layer 1 which is a physical layer of a radio section signal system between a mobile station and a base station as viewed from a seven-layer model of an en Systems Interconnection (a layer that guarantees transmission of a bit string using a communication circuit using an electromagnetic wave as a physical transmission medium) Perform synchronization establishment of a frame and a superframe, detect a color code and activate a scrambler, and perform error detection / correction), whether the reception of the BCCH has been completed, or if the reception level is higher than the standby permission level. It is checked whether or not it has become large (the above is a standby start condition). If all perch channels are satisfied, the perch channel is set as a standby control channel and the standby state is entered (switches when the standby control channel determined by the control channel structure information of the BCCH is different). . If the layer 1 does not operate normally or the reception level becomes equal to or lower than the standby permission level for all the selection channels stored in the memory, the process returns to the perch channel scan. In this manner, in the standby state, the standby control channel transmitted from the nearest base station having the highest reception level in the mobile communication network can be caught, and communication with the base station can be performed with low power (standby control). (A reception permission level, identification information of a mobile communication network, a location registration area number, control channel structure information, regulation information, and the like are received on the BCCH of the channel, and an incoming call signal is received on the PCH.)

[0004]

If the mobile station is located in a place where radio waves of the home operator's mobile communication network to which the mobile station subscribes cannot reach, no matter how much the standby control channel capturing operation is executed, the mobile station will not fail. And cannot be caught. Therefore, in order to prevent rapid consumption of the battery, the power supply of the receiving system circuit of the mobile station is intermittently turned on, and the capturing operation of the control channel to be awaited in the home operator mobile communication network is intermittently executed. . However, the power off time of the receiving system circuit (pause period T _Y )
If it is too long, even if it moves to a place where radio waves can reach, it does not immediately shift to the standby state, and there is an inconvenience that it is impossible to make a call. Therefore, set it to about several seconds (FIG. 6 (1)). reference). By the way, the mobile station is permitted to use the mobile station in any other operator mobile communication network not directly subscribed (roaming, the other operator mobile communication network is called a roaming operator mobile communication network). In this case, when the mobile phone goes out of the service area, it is not known which of the home operator's mobile communication network and the roaming operator's mobile communication network can be captured. It has to do both the acquisition operation of the control channel to wait in the mobile communication network. At this time, as shown in FIG. 6 (2), when the time schedule of the capturing operation in the home operator's mobile communication network, the capturing operation in the roaming operator's mobile communication network, and the suspension is repeated, compared to FIG. 6 (1). As a result, the energization ratio of the receiving system circuit is increased, the battery is consumed greatly, and the standby duration becomes extremely short. Lowering the power energization percentage by extending the T _Y To solve this problem, the transition time to the standby state it takes longer.

The present invention has been made in view of the above-mentioned problems of the prior art,
It is an object of the present invention to provide an out-of-service standby method for mobile communication in which power consumption is kept low without significantly delaying a transition time from an out-of-service to a standby state.

[0006]

SUMMARY OF THE INVENTION In a mobile communication out-of-service standby method according to the present invention, a mobile station is a home operator mobile communication network to which the mobile station subscribes or a roaming operator mobile communication permitted to roam. When the network changes from the standby state to the out-of-service state, while the power of all or a part of the receiving system circuit of the mobile station is intermittently turned on, the operation of capturing the control channel to be awaited by the home operator mobile communication network is performed. The acquisition operation of the control channel to be awaited by the ROHM mobile communication network is executed intermittently, and the acquisition operation of the control channel to be awaited by the home operator mobile communication network is controlled by the control to be awaited by the ROHM mobile communication network. The operation is performed more frequently than the channel acquisition operation, and when the control channel is acquired, the state shifts to the standby state. There.

[0007]

According to the mobile communication out-of-service standby method of the present invention, when the mobile station is in the out-of-service state, the power of all or a part of the receiving system circuit of the mobile station is intermittently turned on while the home operator moves. The intermittent operation of capturing the control channel to be awaited in the communication network and the capturing operation of the control channel to be awaited in the ROHM mobile communication network is performed. The operation is performed at a higher frequency than the operation of capturing the control channel to be awaited in the roaming operator's mobile communication network, and when the control channel is successfully captured, the state shifts to the standby state. When the mobile station is in the service area of the home operator mobile communication network, the acquisition operation of the control channel of the home operator mobile communication network is performed at a high frequency per unit time, so the transition time from the out-of-service state to the standby state is Compared to a mobile station that does not have a roaming function, there is not much delay and the user does not have to wait long before he can make a call. When the service area of the home operator's mobile communication network and the ROHM operator's mobile communication network overlap, the priority of the home operator's mobile communication network increases the convenience for users in terms of communication costs and enjoyment of various services. high. In addition, even when the service area of the home operator mobile communication network and the roaming operator mobile communication network do not overlap, the user is often considered to use the mobile station in the home operator mobile communication network. You do not have to wait until you are in the standby state. Even when the user is in a place where communication is possible only through the ROHM mobile communication network, the operation of capturing the control channel of the ROHM mobile communication network can be reliably performed.
Roaming can be used. In addition, since the frequency of the operation of capturing the control channel of the ROHM mobile communication network is low, it is possible to keep the power consumption low and the standby duration long.

[0008]

EXAMPLES overall configuration diagram 1 is a block diagram showing the structure of an embodiment of a mobile station embodying the out-of-service standby method for a mobile communication according to the present invention (the mobile phone). Here, the mobile station is a home operator mobile communication network (hereinafter referred to as a home network) to which the mobile station subscribes.
And a roaming operator mobile communication network (hereinafter referred to as a roaming network) permitted to roam. An operation / display unit 1 includes various keys such as a power key, an off-hook key, and a dial key, and a display that performs various displays such as an out-of-range display, a reception level display, a dial display, and a battery exhaustion display. Reference numeral 3 denotes a speaker, 4 denotes a voice coder / decoder (CODEC), 5 denotes an antenna, and 6 denotes a radio unit (RFU). The duplexer 6A performs amplification of an antenna reception signal, frequency conversion, and IF amplification. Receiving circuit 6B, demodulator (π / 4 shift QPSK)
Demodulator) 6C, modulator (π / 4 shift QPSK modulator)
6D, a transmission circuit 6E for performing frequency conversion and power amplification of the modulator output, and a frequency synthesizer 6F for outputting a local oscillation signal for frequency conversion and the like. When performing intermittent reception, the power of each circuit except the transmission system circuit (the modulator 6D and the transmission circuit 6E) of the wireless unit 6 is intermittently turned on under the control of a controller described later. The power of the transmission circuit is turned on only when transmission is required. The receiving circuit 6B also has a built-in receiving level detector (not shown).

Reference numeral 7 denotes a TDMA circuit (time division multiplexing / demultiplexing circuit), which combines information data such as control channel data for transmission and audio data and a synchronization word and stores them in a predetermined time slot in a TDMA frame. Burst output to modulator 6D or TDMA input from demodulator 6C
A necessary time slot is extracted from the frame, frame synchronization and super frame synchronization are performed, color code detection, activation of a scrambler, error detection / correction, and the like are performed, and control channel data and audio data are separately output. The TDMA circuit 7 has a function of detecting synchronization between a frame and a superframe for a received slot,
It also has a function of detecting whether or not the correction is normal. Reference numeral 8 denotes a controller constituted by a microcomputer, which uses a program stored in a built-in memory, its own model number, a perch channel frequency of each of the home network and the ROHM network, information for identifying the home network and the ROHM network, and the like. By controlling the various parts of the mobile station and performing various judgment processes, the power is turned on according to the operation of the power key, out-of-service standby for the home network and the ROHM network, normal standby after capturing the standby control channel, incoming call, off-hook key and dialing A control process such as calling and ending a call in response to a key operation is executed while exchanging various control information with a base station.

In this embodiment, when waiting in the out-of-service state, the controller 8 controls the acquisition operation of a control channel to be awaited while giving priority to the home network. That is, as shown in FIG. 2, the power supply of the wireless unit 6 (excluding the transmission system circuit) is intermittently turned on while a pause period of T _Y seconds is taken, and the control to wait for the home network during each ON period is performed. Although the channel acquisition operation is performed once each time, the operation of capturing the control channel to be awaited by the ROHM network is the same as that of the home network.
/ N (n is an integer of 2 or more). In places where the service areas of the home network and the ROHM network overlap, the home priority has advantages in terms of communication costs, answering machine service, transfer phone service, and the like.

FIG. 3 is a flowchart showing a process after the power is turned on by the controller 8, FIG. 4 is a flowchart showing an out-of-service standby process, and FIG. 5 is an explanatory diagram of an out-of-service standby operation. The out-of-service standby operation of the embodiment will be described. Note that, here, the frequency band of the home network and the frequency band of the ROHM network are different, but the service areas are assumed to overlap (see FIG. 5; symbols Z ₁ and Z ₂ in the figure indicate mobile stations). . Also, it is assumed that the mobile station is permitted to use the mobile station in both the home network and the roam network, and T _Y = 2 seconds and n = 4. Status flag AF
Is set to 0 when the operation of capturing the control channel to be awaited is performed only for the home network (fixed mode), and is set to 1 when the operation is performed for both the home network and the ROHM network (variable mode).

Powering On Now, assuming that the mobile station is in a place where radio waves of the home network can be received, when the power key is pressed on the operation / display unit 1,
The controller 8 turns on the power of each unit such as the wireless unit 6 (excluding the transmission system circuit) and the TDMA circuit 7 (step S1), sets the AF to 1, and sets the variable mode (step S2). Next, a control operation for capturing a control channel to be awaited in the home network is controlled (step S3). Specifically, it performs reception tuning control for the wireless unit 6, scans the perch frequency of the home network stored in the built-in memory, associates a perch channel whose reception level is equal to or higher than a specified value with its reception level, and selects Store as a channel (perch channel scan). Next, while tuning to the selected channel this time in the order of higher reception level,
The TDMA circuit 7 establishes synchronization between the frame and the superframe, activates the scrambler, detects and corrects errors, and outputs control channel data. And (1) TDMA
In the circuit 7, the synchronization is detected, the error detection / correction is normally performed (the layer 1 is operating normally), and (2) each information of the BCCH in the control channel (standby permission level, movement Communication network identification information, location registration area number, control channel structure information, regulation information, etc.) are correctly received, (3) the reception level is higher than the standby permission level defined by the BCCH, and (4) the movement of the BCCH. It is checked whether all the stand-by start conditions such as that the identification information of the communication network matches the identification information of the home network stored in the built-in memory are satisfied (step S4). It enters a standby state as a control channel to be standby in the home network (step S5). At this time, if a transition to another control channel is instructed on the BCCH, the mobile station shifts to the other control channel as a control channel to be awaited, and enters a standby state. If an event such as an outgoing call or an incoming call occurs with the home network during standby, the controller 8 performs predetermined call control, incoming call control, and the like on each unit according to the event.

[0013] The out-of-service standby (see Z ₁ of FIG. 5) (Fig. 2, see FIG. 5) during the standby in the home network, to go out of the reach of radio waves, waiting the reception level from the base station of the serving zone deterioration level When the reception level from the base station in the peripheral zone falls below the standby permission level, the controller 8 determines that the mobile station is out of the home network and proceeds to the flow of FIG. 4 to execute the out-of-service standby process. First, it is checked whether the status flag AF is 0 (step S10),
Since it is NO, it is set to 0 and the scan target is fixed to the home network,
The count value C of a counter (not shown) that counts the number of intermittent receptions in the fixed mode is cleared (step S1).
1, S12). And the radio unit 6 only for T _Y = 2 seconds
Of the receiving circuit (the receiving circuit 6B and the demodulator 6C) is turned off (the transmitting circuit remains in the power-off state), and TD
The MA circuit 7 is suspended in a standby mode, which is a low power consumption mode (step S13).

Next, it is checked whether or not C is smaller than (n-1) (step S14). Since it is initially NO, the process returns to step S3 in FIG. Power supply to all parts except TDMA
The standby mode of the circuit 7 is released, and the control channel to be awaited in the home network is captured. If the mobile station is still out of the range of the home network where radio waves cannot reach and cannot be captured, and the result of step S4 is NO, it is checked whether the status flag AF is 0 (step S6).
After step S10, the process proceeds to step S15, where the count value C of the counter is incremented by one. Hereinafter, until the control channel to be awaited in the home network can be captured or C reaches (n-1),
The same processing is repeated, and the operation of capturing the control channel to be awaited in the home network is intermittently repeated.

When C reaches (n-1) while the control channel cannot be captured by the home network, the controller 8 sets the status flag AF to 1 and sets the mode to the variable mode (steps S14 and S16). Then, after the operation of capturing the control channel to be awaited in the home network is performed once (step S3), the answer is NO in step S6, so the process proceeds to step S7, where the power of the receiving system circuit of the wireless unit 6 is turned on, and the TDMA circuit 7, while the standby mode is released, the control channel to be awaited in the ROHM network is captured (step S7). This capturing operation is almost the same as in the case of the home network, except that the perch channel scan of the ROHM network is performed first and (4) in the standby start conditions (1) to (4) are replaced by (4). 'The identification information of the mobile communication network of the BCCH is identical to the identification information of the ROHM network stored in the internal memory.

Thereafter, the controller 8 checks whether all the standby start conditions are satisfied for the ROHM network (step S8). If the mobile station is out of reach of the ROHM network and cannot be captured, and the result is NO, step S
The process proceeds to S11 via 10, and the mode is again set to the fixed mode, and C is cleared (step S12). Then, the intermittent operation (n-1) times is performed for the control channel to be awaited for only the home network while taking the idle period every two seconds.
If it is still not possible to capture, the home network and the roaming network are continuously connected to perform the control channel capturing operation once, and if it is still not possible to capture, the control channel is intermittently (n-1) times.
The process of performing the operation of capturing the control channel to be awaited only for the home network is repeated (above, out-of-service standby; see FIG. 2).

Transition from out-of-service standby to home network standby
When the mobile station comes to a position where radio waves can reach both the home network and the roaming network during the out-of-range standby mode, the operation of capturing the home network is higher than that of the roaming network. There is a high probability that the channel will be acquired. Therefore, the control channel of the home network is immediately captured, and if all the standby conditions are satisfied, the state shifts to the standby state in the home network (steps S4 and S5). The home network is more advantageous in terms of communication costs and services than the ROHM network, and if communication is possible, catching the home network is more convenient for the user.

Transition from out-of-service standby to roaming network standby
When the mobile station comes to a position where radio waves can reach only the ROHM network during the out-of-range standby mode, the control channel of the ROHM network is also captured in step S7. Therefore, the control channel of the ROHM network is captured, and the standby condition is satisfied. If all holds,
Transition to the standby state in the ROHM network (step S8,
S9). This enables communication in a wide area utilizing the roaming function.

When the control channel acquisition operation of the home network is performed when the power is turned on, if the standby activation condition is not satisfied (NO in step S4), AF is initially 1 and the process advances to step S7 via step S6, and the roaming operation is performed. An operation of capturing a control channel to be awaited in the network is performed. If all the standby start conditions are satisfied for the ROHM network, the standby state is set (steps S8 and S9). If not satisfied, the process shifts to the out-of-service processing of FIG.

According to this embodiment, when the wireless unit 6 enters the out-of-service state, the power of the wireless unit 6 is intermittently turned on, and the control channel to be awaited in the home network and the control channel to be awaited in the ROHM network are captured. The operation is performed intermittently. At this time, the operation of capturing the control channel to wait on the home network is performed more frequently than the operation of capturing the control channel to wait on the ROHM network. The frequency of operation can be reduced, the power consumption can be kept low, and the standby duration can be kept long. When the mobile station is in the service area of the home network, the operation of capturing the control channel of the home operator mobile communication network is performed at a high frequency per unit time, so the transition time from the out-of-service state to the standby state is a roaming function. Is not much delayed compared to a mobile station that does not have, and the user does not have to wait long before he can make a call. When the service areas of the home network and the ROHM network overlap, the home network is given priority,
It is highly convenient for users in terms of communication costs and enjoyment of various services. In addition, even when the service areas of the home network and the ROHM network do not overlap, in many cases, it is considered that the user uses the mobile station in the home network, so that the user does not have to wait until the state changes from the out-of-service state to the standby state. Even if the user is in a place that can only communicate via the ROHM network,
Since the operation of capturing the control channel of the roaming network can be reliably performed, roaming can be used.

Although the above embodiment has been described by taking a cellular phone as an example, the present invention can be similarly applied to other types of mobile communication such as PHS, PDA, MCA, and pager. In addition, T _{Y is set} to 2 seconds, but may be set to another time such as 1.5 seconds or 3 seconds, or T _Y may be changed in the middle of out-of-service standby. Further, n is 3, 5,
Other settings such as 6 may be used. The suspension of the reception may be performed by turning off only a part of the power supply such as the reception circuit 6B in the reception system circuit. Further, the first pause period after the mobile phone goes out of the service area may be omitted.

[0022]

According to the mobile communication out-of-service standby method of the present invention, when the mobile station is out of service, all or a part of the power supply of the receiving system circuit of the mobile station is turned on intermittently.
Intermittently executes the control channel capture operation to be awaited by the home operator mobile communication network and the control channel capture operation to be awaited by the roaming operator mobile communication network. Is performed more frequently than the capturing operation of the control channel to be awaited in the ROHM mobile communication network, so that when the mobile station is within the service area of the home operator mobile communication network, the home operator mobile communication network Control channel acquisition operations are performed at a high frequency per unit time,
The transition time from the out-of-service state to the standby state is not so much delayed as compared with a mobile station that does not have a roaming function, and the user does not have to wait long before he can make a call. When the service area of the home operator's mobile communication network and the ROHM operator's mobile communication network overlap, the priority of the home operator's mobile communication network increases the convenience for users in terms of communication costs and enjoyment of various services. high. In addition, even when the service area of the home operator mobile communication network and the roaming operator mobile communication network do not overlap, the user is often considered to use the mobile station in the home operator mobile communication network. You do not have to wait until you are in the standby state. Even when the user is in a place where communication is possible only through the roaming carrier mobile communication network, the control channel of the roaming carrier mobile communication network can be reliably captured, so that roaming can be used. In addition, since the frequency of the operation of capturing the control channel of the ROHM mobile communication network is low, it is possible to keep the power consumption low and the standby duration long.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an embodiment of a mobile station embodying a mobile communication out-of-service standby method according to the present invention.

FIG. 2 is an explanatory diagram showing a time schedule at the time of out-of-service standby;

FIG. 3 is a flowchart showing the operation of the controller.

FIG. 4 is a flowchart showing the operation of the controller.

FIG. 5 is an explanatory diagram of an out-of-service standby operation.

FIG. 6 is an explanatory diagram of a conventional out-of-service standby operation.

[Explanation of symbols]

1 operation / display unit 5 Antenna 6 wireless unit 6B receiving circuit 6C demodulator 7 TDMA circuit 8 controller Z _1, Z ₂ mobile station

Claims (1)

(57) [Claims] When a mobile station changes from a standby state to an out-of-service state with respect to a home operator mobile communication network to which the mobile station subscribes or a roam operator mobile communication network permitted to roam, the mobile station moves. While intermittently turning on all or some of the receiving system circuits of the station, the operation of capturing the control channel to be awaited by the home operator mobile communication network and the operation of capturing the control channel to be awaited by the roaming operator mobile communication network are performed. It is executed intermittently. At this time, the operation of capturing the control channel to be awaited in the home operator mobile communication network is performed more frequently than the operation of capturing the control channel to be awaited in the roaming mobile communication network. The mobile communication system is configured to transition to a standby state when the mobile phone can be captured.