JPH07327256A - Controlling system for standby of mobile station in mobile radio - Google Patents

Abstract

PURPOSE:To perform smooth switching to the waiting state to improve the responsiveness of a mobile station by periodically performing discrimination using the level difference to acquire a control-channel. CONSTITUTION:A control part 2 uses an input/output interface 21 between the part 2 and an RF part 1 and a RAM 24 as the work memory and executes the control operation in accordance with control processing procedures stored in a ROM 23. First and second thresholds having different levels are set, and the reception channel radio intensity is compared with these thresholds, and the operation is switched to the normal control channel operation when the reception channel radio intensity is lower than the first threshold, and the control channel scanning operation is executed at intervals of a time longer than normal when it is higher than the first threshold and is lower than the second threshold. Thus, the processing is quickly performed in accordance with the radio condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a standby control system for a mobile station in mobile radio, and more particularly to a standby control system for a mobile station in mobile radio for achieving low power consumption and quick control.

[0002]

2. Description of the Related Art In the current mobile radio system, a plurality of service networks often exist as service units such as dividing service areas even for the same operator. In such a system, there are a service network (home network) to which a mobile station contracted as a mobile terminal belongs, and another home network that is not contracted but can operate with the same mobile terminal. The user normally uses the home network, but can also use a service (roaming contract) that enables communication via this other available service network when the user moves greatly.

In a system in which there are a plurality of service networks provided by the same operator, when a mobile station is located near a service network where services are not permitted, it is near the border of the service area of the home network. And
The strength of the radio wave transmitted from the home network is weak. Conventionally, in such a situation, the mobile station performs a control channel scan operation as shown in FIG. 4 in order to capture an effective channel and transit to a standby state.

That is, first, the control channel is scanned (step S31), and the presence or absence of an effective channel is determined (step S32). If there is an effective channel, the active channel transits to a standby state and there is no effective channel. At times, the service is not permitted, that is, the display indicating that the service is out of service is turned on (step S33). Then, the pause timer T1 for intermittent scanning is started (step S34), the time-out of the timer T1 is confirmed (step S35), the control channel scanning operation of step S31 is returned to, and intermittent scanning is performed.

[0005]

As described above, in the conventional mobile station standby control system, when the radio field intensity received by the mobile station is lowered, the control channel is scanned and then an effective channel exists. If not, the same scan is repeated after a certain time has elapsed after entering the sleep state.

However, in the above case, the scanning is unnecessarily repeated and there is a problem in terms of power consumption. This problem can be alleviated to some extent by increasing the time in the dormant state, but if the time in the dormant state is lengthened, the radio wave reception state of the mobile station changes from moment to moment.
It becomes difficult to quickly respond to changes in radio wave conditions.

Further, the control channel scanning operation results in a standby state at the frequency fA having the highest radio field intensity. For example, if the country code and the business group number do not match,
If it does not belong to the home network or the permitted network in the group, is under maintenance regulation, is different from the roaming non-permitted network or location registration failure location number, etc.
If, for some reason, the device cannot be started up and the standby state is not reached, the standby state is reached at the frequency fB having the next highest radio wave intensity.

However, since the radio wave of the frequency fA is stronger than the radio wave of the frequency fB, it exceeds the standard of the zone transition level difference (standby permission level-standby deterioration level), causing quality deterioration and restarting the frequency fA. ,
After that, it falls into an infinite loop, becomes inoperable, and cannot reach a stable standby state. That is, for example, even if the reception level of the frequency fA is equal to or higher than the threshold that can be determined as a predetermined effective channel,
When the reception data of the frequency fA cannot be put into the standby state due to a defect or the like, the frequency fB having the next highest reception level is received. When the difference between the reception levels of the frequencies fA and fB is equal to or more than a certain value, the frequency fA is received again, but the received data content is defective, so the operation of receiving the frequency fB is performed again, and eventually the frequency fA → fB. → fA → f
The operation is repeated indefinitely as B → ..., and the stable standby state cannot be entered.

Therefore, an object of the present invention is to provide a mobile station standby control system in mobile radio capable of reducing the power consumption of the mobile station and rapidly changing to a stable standby state according to the received radio wave state. It is in.

[0010]

In order to solve the above-mentioned problems, a mobile station standby control method in mobile radio according to the present invention captures an effective channel from a plurality of frequency channels transmitted from a base station and waits. Transition to the state,
When there is no effective channel, it is set in advance in the standby control method of the mobile station in the mobile radio that is in the standby state on the frequency channel of the best condition searched by the control channel scanning operation at the predetermined time interval based on the received radio signal. Further, the first and second thresholds having different levels are compared with the reception channel radio field intensity, and when the reception channel radio field intensity is smaller than the first threshold, the control channel scanning operation is started. , The control channel scan operation is performed at a time interval longer than the predetermined time interval when the first channel is larger than the first threshold and smaller than the second threshold. Here, during the operation of shifting to the standby operation, the channel whose condition is insufficient as the standby state is stored in the memory, and the channel stored in the memory is not scanned during the subsequent scanning operation.

[0011]

In the present invention, the first having different levels
And a second threshold are set, the reception channel radio field intensity is compared with these thresholds, and when the reception channel radio field intensity is smaller than the first threshold value, a normal control channel scan operation is performed, Further, when it is larger than the first threshold and smaller than the second threshold, the control channel scan operation is executed at a time interval longer than the normal time interval to immediately respond to low power consumption and radio wave conditions. Enables quick processing. At this time, a channel whose condition is insufficient as a stand-by state is stored in the memory, and no scanning is performed during the subsequent scanning operation, thereby enabling real-time operation.

[0012]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a flowchart showing a processing procedure of an embodiment of a mobile station standby control system in mobile radio according to the present invention. Further, FIG. 3 shows a configuration example of the mobile station.

In FIG. 3, the mobile station comprises an RF section 1 and a control section 2, and outputs a signal inputted from an antenna ANT to the RF section.
It is received by the section 1 and passed to the control section 2. The RF unit 1 has a synthesizer unit 11 for setting a transmission / reception frequency to establish superframe synchronization, and the control unit 2 has an input / output interface (I / F) 21 with the RF unit 1 and a RAM 24.
Is used as a work memory, and has a CPU 22 for executing a control operation in accordance with a control processing procedure program stored in a ROM 23. Further, the control unit 2 stores an error table 2 for storing the condition-deficient channels in the standby state.
5 are provided.

In this embodiment, after the power is turned on, first,
The control channel is scanned (so-called perch channel scan) (step S1), and it is determined whether or not there is an effective channel (step S2). This determination is based on the following five conditions, # 1: reception level equal to or higher than the standby permission level, # 2: country code / business group number match, #
3: Belong to home network or group permission network,
# 4: Maintenance regulation is not applied, and # 5: Different from the roaming non-permitted network or the location registration failure location number stored. If all of the above 5 items are satisfied, it is determined that there is an effective channel,
Transition to the standby state. Also, when one item condition is not satisfied, it is determined that there is no effective channel, but the above-mentioned item conditions: # 1 and # are not entered unconditionally in the dormant state (scan after a certain period of time) as in the conventional case. When there is a channel satisfying 2 (necessarily required for discontinuous reception), the channel shifts to the discontinuous reception state after waiting for a change in BCCH on that channel.

In the above, the perch channel is the channel that initially looks for the call channel information by default.
Maintenance regulations include regulations that make it unusable during maintenance by the supplier side.
BCCH means a channel for broadcasting control information.
Incidentally, the channel is composed of a control channel (CCH) and an information channel (TCH), and the control channel has a broadcast channel (BCCH), a common control channel (CCCH), a user packet channel (UPCH), an associated control channel, etc. The information channel contains call information. About these, RC version of B revised edition issued on December 10, 1992 from the Radio System Development Center of Japan.
It is defined and explained in detail in R STD-27B “Digital Car Telephone System Standard”.

The BCCH change indicates a change in broadcast information,
It is possible to check that the state is changed to satisfy the above items # 3 to # 5, and if there is a change in the notification content of items # 4 and # 5, a reset start is applied. In the BCCH change waiting state, when the message of the broadcast information is received by paging, the state is exited, but this alone cannot quickly respond to the change in the radio wave state by the mobile station. This is because, for example, while moving to another zone, the BCCH change waiting state continues even though the frequency (effective channel) having the next highest reception level can be received.

Therefore, in order to periodically check the radio field intensity (level) of the currently received channel frequency, two threshold levels ("HIGH" and "HIGH" and " LOW ")
Is set, and the level of the electric wave being received and the above two threshold levels are compared periodically,
The next operation is determined based on the comparison result.

In the present embodiment, the radio field intensity currently being received is
Check at the level of the receiving slot of the own station in the TDMA method.

This comparison operation will be described with reference to the flow chart of FIG. If it is determined in step S2 that there is no valid channel, it is determined whether or not there is a home network or a non-permitted network within the group of item # 3 (step S3
3) If there is none, scanning is performed after a certain period of rest, and if there is, the out-of-range display is turned on (step S4), and a change waiting timer (20 seconds) is started (step S5). Next, BC
Wait for CH change, receive intermittently (step S6), and determine whether the timer has timed out (20 seconds elapsed) (step S6).
7) The steps S6 and S7 are repeated until the time-out is reached. This process checks the change of the BCCH every 20 seconds, waits for the change, and determines whether or not the intermittent reception can be cancelled.

Then, when the reception level of the own station slot is between the above-mentioned two thresholds "HIGH" and "LOW", for example, near the boundary of the service area, the flag (Flag) set is set. It is determined whether or not it has been set (step S8), and if it is set, the flag is reset (step S12), and then step S1.
Return to the process of No. and if not set, the own station slot reception level (RSSI) is the threshold "LOW".
It is determined whether it is lower than (step S9).

Here, when the receiving level of the own station slot is lower than the threshold "LOW", that is, when the received signal is extremely low or absent, it is considered that another base station exists nearby. Then, the process returns to step S1 to perform the control channel scan. If the reception level is higher than "LOW", it is determined in step S10 whether it is lower than "HIGH". Where Y
If it is ES, the signal level is between "HIGH" and "LOW", that is, it is determined that the signal is considerably weak, a flag indicating that is set in step S11, and the processes of steps S5 to S7 are executed again. Then, the process branches to the YES side in step S8, the flag is reset in step S12, and the process returns to the initial setting reception state step S1. On the other hand, if NO in step S10, the process returns to step S5, but in this case, since the flag is not set, the process continues between steps S5 and S10 until the BCCH changes. If the reception level is higher than the threshold "HIGH", it is considered that the home network is not present nearby.

FIG. 2 shows how the reception level changes when the mobile station is moving.

Now, consider a case where a strong signal exceeding "HIGH" is received outside the service area of the home network in the state after step S5 in FIG. At this time, since the flag in step S11 is not set, as described above, only intermittent reception is performed to see the change in BCCH once every 20 seconds. Therefore, the power consumption is the lowest.

Next, when the mobile station moves as shown by the arrow in FIG. 2 and comes between "HIGH" and "LOW", the signal outside the service area being received has weakened, so that the own station It is determined that the service area has been approached, the flag is set in step S11, the flag is recognized in step S8, the loop is exited, and a normal control channel scan is started. At this time, if the home network base station can receive at a level of "LOW" or higher, communication through the home network becomes possible. When the home network base station cannot receive the signal, a control channel scan is performed every two rounds of the loop of FIG. 1 to monitor the home network. Further, when the mobile station moves and enters the range of the home network, the normal operation of performing a normal control channel scan is performed. It goes without saying that the reverse operation is performed when the direction of movement is within-range → out-of-range.

By the way, in the above-mentioned standby transition operation, the channel for which the condition is insufficient to enter the standby state is
Even if the level is high, it is not efficient to go to start-up each time a scan is performed, and there is a problem of real-time operation of the mobile station. Therefore, in the present embodiment, as shown in FIG. 3, an error table 25 as a memory is built in the control unit 2, and a channel with insufficient conditions is not activated from the second time and is created after scanning. It is not included in the level order table. Further, the error table 25 is used to prevent the restart even if the level difference causes quality deterioration.

[0026]

As described above, according to the present invention,
Intermittent reception with reduced power consumption is possible, and by making periodic judgments using level differences, it is possible not only to capture the control channel and make a smooth transition to the standby state, but The processing is eliminated and the responsiveness of the mobile station is also improved.

[Brief description of drawings]

FIG. 1 is a flowchart showing an operation processing procedure of an embodiment of a mobile station standby control system in mobile radio according to the present invention.

FIG. 2 is a diagram for explaining the operation of the embodiment shown in FIG.

FIG. 3 is a block diagram showing a configuration example of a mobile station in the embodiment of the present invention.

FIG. 4 is a flowchart showing an operation processing procedure of a mobile station standby control method in conventional mobile radio.

[Explanation of symbols]

 1 RF Unit 2 Control Unit 11 Synthesizer 21 Input / Output IF 22 CPU 23 ROM 24 RAM 25 Error Table

Claims (2)

[Claims] 1. An effective channel is captured from a plurality of frequency channels transmitted from a base station and transits to a standby state,
When there is no effective channel, it is preset in the standby control method of the mobile station in the mobile radio that is in the standby state on the frequency channel of the best condition searched by the control channel scanning operation at the predetermined time interval based on the received radio signal. First and second with different levels
Of the threshold and the reception channel radio field intensity, when the reception channel radio field intensity is smaller than the first threshold, shift to the control channel scanning operation, larger than the first threshold, A mobile station standby control method in mobile radio that executes the control channel scan operation at a time interval longer than the predetermined time interval when the value is smaller than the second threshold. 2. A channel whose condition is insufficient as a stand-by state is stored in a memory during the stand-by operation transition operation, and a channel stored in the memory is not scanned during a subsequent scan operation.
2. A mobile station standby control method in the mobile radio described in.