JP3769501B2 - How to avoid call failure due to time slot error - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for avoiding a call impossible state due to a time slot error. More specifically, in intermittent reception performed while a mobile phone is waiting for a call, a data reception time slot of a general call channel that should be received for some reason. The present invention relates to a detection method for detecting a time slot error in a mobile phone that has been in a call waiting state at a different timing.
[0002]
[Prior art]
Japanese Patent Application Laid-Open No. 60-62746, which is cited as a first conventional example of this kind of technology, describes one control zone by N radio zones by N radio base stations (N is an integer of 1 or more). And a call control channel and a subsequent incoming control channel are set between the mobile station and the radio base station in the control zone, and the incoming control channel includes a plurality of continuous times. In a mobile radio system that has a frame structure consisting of slots, and that incoming call control is transmitted and received between the radio base station and the mobile station in relation to one incoming call information for one time slot, there was an incoming call. Either one or both of information related to the call number of the mobile device (mobile device number) and the information indicating the position of the time slot in the frame in which this information is broadcasted are received from the base station side. In mobile radio in which the mobile station receives intermittently only the necessary time slots in the frame constituting this channel when receiving the incoming call control channel according to the information received in advance. An intermittent reception method is disclosed.
[0003]
Japanese Laid-Open Patent Publication No. 1-170129, which is cited as a second conventional example, shows a call signal including information for specifying a receiver and information contents transmitted to the receiver specified by the call signal. A signal generator that transmits information signals, a transmitter that transmits each signal transmitted from the signal generator as a radio signal, and a receiver that receives a radio signal transmitted from the transmitter In the wireless communication system, the time slot for signal transmission is divided into a part for sending a call signal and a part for sending an information signal, and the call signal is specified by at least a receiver number and a receiver number indicating the destination of information contents And a reception control signal indicating the timing at which the information signal addressed to the selected receiver is transmitted, and the receiver determines the time at which the information signal addressed to another receiver is transmitted. Selective call communication system to pause the reception, is disclosed Te.
[0004]
Japanese Patent Laid-Open No. 6-112892, which is cited as a third conventional example, discloses that each time slot can be used for transmitting a message signal between a mobile station and a base station in a cellular telephone network. A message signal generating means for generating a message signal to be transmitted as a series of binary bits in a number of time slots of a frame, as a system utilizing a certain number of said time slots of a radio channel frame as Synchronization word generating means for generating an associated time slot related synchronization word for each of the time slots, each time slot indicating whether the time slot is a first type channel or a second type channel. The synchronization word generating means including channel display information to be displayed and a message in each of the time slots. A frame creating means for creating a frame including a plurality of the time slots, a transmitting means for transmitting the frame, a receiving means for receiving the frame, and a detection for detecting channel display information by assigning a signal and an associated synchronization word And means for determining whether each of the time slots should be utilized as a traffic channel or as a control channel in response to detection of either the first type channel or the second type channel. A system characterized by this is disclosed.
[0005]
Furthermore, Japanese Patent Application Laid-Open No. 8-228377, which is cited as a fourth conventional example, allows a single slave unit to be called from the private and public master units. In the system that can respond to necessary incoming calls from the master unit, the slave unit detects the presence or absence of synchronization bursts transmitted from multiple master units through the reception slots at different time periods, and is included in the synchronization burst If it is determined from the identification code that this synchronization burst is addressed to the time station, the synchronization burst to which the identification code of its own station is added via the transmission slot after a predetermined slot counted from the reception slot that received the synchronization burst is sent to the master unit side. The synchronization is established by returning it, and the identification code of the master unit in the received synchronization burst is stored in association with the reception slot, thereby making it possible to send and receive calls via a plurality of master units of one slave unit. Synchronization establishing method of a digital wireless telephone system is enabled, it is disclosed.
[0006]
[Problems to be solved by the invention]
However, in the first conventional example, it is described that the mobile station number is transmitted in the call control channel, and the mobile station receives intermittently in a specific time slot determined by the mobile station number. In the conventional example, it is described that the presence / absence of the local station information is recognized based on the receiver number in the calling signal and the intermittent reception process is performed. In the third conventional example, the mobile station controls the control channel. It is described that the time slot is identified by recognizing the unique indicator of the time slot to be used as the second conventional example. In the fourth conventional example, the time slot is identified based on the identification code included in the synchronization burst transmitted from the master unit. Although it is described that it is determined whether or not it is destined for the station and intermittent synchronization is established, in any of the above conventional examples, the local paging channel that should be received for some reason If the became a call waiting at a timing different from that of the reception time slot, it was not possible to detect the time slot error.
[0007]
That is, each of the first to fourth prior arts is an invention of a part for intermittent reception or a part for receiving a call.
[0008]
The present invention has been made in view of the above-mentioned circumstances inherent in the prior art, and therefore the object of the present invention is to perform an intermittent reception performed while waiting for a mobile phone call for the local station that should be received for some reason. It is an object of the present invention to provide a novel detection method capable of detecting a time slot error in a mobile phone that has been in a call waiting state at a timing different from a data reception time slot of a general call channel.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, a method for avoiding a call impossible state due to a time slot error according to the present invention uses the mobile station identifier MSI in the general call channel PCH received during the intermittent reception operation. The number of radio channels NC in one zone, the number of PCH groups of the general call channels in the radio channel, and the MSI of the local control channel when the transition to the call waiting state is detected. A calculation is performed to determine whether or not the time slot position of the received general call channel PCH is a time slot that should be received by the own station. When a time slot error is detected, the timing of the base station is detected. After the calculation of the local station control channel, the operation shifts to the intermittent reception operation again.
[0010]
A method for avoiding a call impossible state due to a time slot error is also executed by a first processing step for executing synchronization adjustment processing and reception processing with a base station, and subsequent to the first processing step. Following the second processing step, the third processing step that is executed subsequent to the second processing step, and the transition processing from the BCCH reception to the intermittent reception processing, and the third processing step. And a fourth processing step for comparing the expected value with the calculated IP.
[0011]
The first processing step searches the received data for the bit pattern of the synchronization word SW and SSW in order to synchronize with the base, performs data reception processing after the completion of synchronization detection, and determines the CAC control signal from the received data. And the type of the acquired data is determined. As a result of the determination, when the broadcast channel is BCCH, the number of radio channels existing in one zone from the received data is NC / 1. It includes a process of acquiring the grouping number NP of the local call channel PCH of the own station, holding it in the storage unit, and acquiring the mobile station identifier MSI from the storage unit.
[0012]
As a result of determining the type of the acquired data, if it is a general call channel PCH of the own station, the number of radio channels existing in one zone from the storage unit NC / 1 the number of PCH groups existing in one radio channel NP is acquired and the mobile station identifier MSI is acquired from received data.
[0013]
The second processing step calculates n by cutting out the lower 2 octets of the mobile unit identifier MSI acquired from the storage unit and expressing it in decimal, and uses the NC and NP acquired from the MSI and received data. N ′ = (n−1) mod (NC × NP) +1 to calculate n ′, IF = (n′−1) mod NC + 1 to calculate IF, and IP = [(n′−1) / NC] +1 is included, and the process includes determining the BCCH / PCH process by holding the IF / IP in the storage unit.
[0014]
As a result of determining whether BCCH / PCH is being processed, the third processing step is calculated according to the current channel and IF = (n′−1) modNC + 1 formula when BCCH is being processed. IF is compared and determined, and if the comparison results in coincidence, the base timing is extracted from the synchronization detection unit, and the timing and IP calculated by the equation IP = [(n′−1) modNC + 1 are compared and determined. If the comparison results in a match, the process includes a process of shifting to the intermittent reception process and starting the PCH reception process.
[0015]
In the fourth processing step, as a result of determining whether BCCH / PCH is being processed in the second processing step, if the PCH is being processed, the IP calculated at the time of BCCH reception is obtained from the storage unit. And comparing the IP and the IP calculated from the PCH data, and if the result of the comparison is a coincidence, the reception timing is not shifted, so the process proceeds to the intermittent reception process, and the PCH reception process is continued. It is out.
[0016]
As a result of comparing and judging the IP calculated at the time of BCCH reception from the storage unit and the IP calculated from the PCH data, if they do not coincide with each other, the reception timing is shifted, so that the process shifts to the timing adjustment process again.
[0017]
An avoidance apparatus for a call impossible state due to a time slot error according to the present invention includes: a wireless unit for transmitting and receiving data; a synchronization detecting unit connected to the wireless unit for synchronizing at a bit level with data of a base station; Display means for notifying the user of the status of an incoming call, input means for the user to operate the mobile phone, the transmission / reception data and display data, input data from the user, mobile phone status Storage means for holding, and the like, connected to the synchronization detection means, the display means, the input means, and the storage means, respectively, to analyze and create the transmission / reception data, control the display means, and change the status of the input means CPU means for performing monitoring and the like.
[0018]
[Prerequisite technology of the invention]
The following is a description of the previous technology for understanding the present invention.
[0019]
FIG. 2 shows a data format of a TDMA time slot used in a mobile phone and a general call channel (hereinafter abbreviated as PCH) in the radio section.
[0020]
In FIG. 2, 21 indicates a time slot of one superframe, and a time slot of one superframe is composed of 36 subframes and has a length of 720 ms.
[0021]
Reference numeral 22 denotes a subframe, and one subframe is a three-time slot including three units, which is a minimum unit having a length of about 6.6 ms, and has a length of 20 ms.
[0022]
Reference numeral 23 denotes a minimum time slot, which is a unit having a length of about 6.6 ms.
[0023]
The unit 23 includes 4 bits R: burst transient response time 24, 48 bits P: preamble 25, 20 bits SW: synchronization word 26, 8 bits CC: color code 27, 112 bits CAC: control signal 28, It consists of 18 bits G: guard time 29, S7 to S9: a synchronization word (SSW) pattern representing the beginning of the superframe, and S1 to S3: a synchronization word (SW) pattern representing other than the beginning of the superframe. ing.
[0024]
FIG. 3 is a diagram showing a signal (20-bit synchronization word pattern) for synchronizing with the base station at the bit level.
[0025]
In FIG. 3, a 20-bit synchronization word (hereinafter abbreviated as SSW or SW) for identifying the head of the superframe and other units. SSW is a synchronization word 30 used in a unit in the first subframe of the superframe, and SW is a synchronization word 31 used in a unit other than the first unit of the superframe. What can be seen here is that in the mobile phone, the synchronization word identifies the beginning of the superframe and the other slots.
[0026]
FIG. 4 is a diagram showing a basic structure of a radio channel.
[0027]
FIG. 5 is a diagram showing an example of the local station control channel = local station calling slot transition operation based on the radio channel (see FIG. 4) and the mobile station identifier (hereinafter abbreviated as MSI) inside the mobile station.
[0028]
The time slot of the general call channel PCH43 received by the mobile phone is determined by the selection operation shown in FIG.
[0029]
In addition, a time slot in which the same calculation is performed in the base station and the mobile phone receives the PCH 43 is a system synchronized with the base station and the mobile phone.
[0030]
FIG. 6 is a timing chart showing an example of intermittent reception operation for receiving the PCH 43 selected in FIG. 5 and reducing the operating current. This intermittent operation is an operation of receiving only the PCH 43 of the own station.
[0031]
FIG. 7 is a diagram showing a data format in the network layer of the PCH 43. By determining the MSI in the received data, the mobile phone determines whether or not it is a call of the own station.
[0032]
The mobile phone shifts to an intermittent reception operation waiting for a call from the base station through the specifications and operations shown in FIGS.
[0033]
The problem with the conventional mobile phone is that if a time slot error is received for some reason during the intermittent reception operation shown in FIG. 6, the PCH transmission time slot of the base station and the PCH reception time slot of the mobile station do not match. It was in the point where it would be unable to call.
[0034]
The time other than the PCH 43, which should not be received while waiting for a call, can receive a data other than the PCH 43 in a call waiting state in a time slot of an information channel, so that a time slot error can be detected. If the synchronization with the slot is erroneously received and the pattern data of the synchronization word SW 26 can be received, the mobile phone cannot detect that the timing with the base station has shifted, and the reception time slot is assumed to be correct from the base station. The intermittent reception operation is continued while waiting for the call. As a result, the call was disabled.
[0035]
Therefore, in the present invention, calculation of an automatic control channel performed when the mobile station identifier MSI in the PCH 43 received during intermittent operation reception is changed to a call waiting state in addition to whether or not there is a call of the own station (see FIG. 5).
[0036]
Since the PCH 43 can be received by a plurality of mobile phones, the PCH 43 for other stations can also be received.
[0037]
Since NC44 and NP45 are parameters common to the radio channels, the time slot position of the received general call channel PCH43 is obtained by calculating the own station control channel using the mobile station identifier MSI (see FIG. 5). It is possible to determine whether or not it is a time slot that the next station should be receiving.
[0038]
When a time slot error is detected, the base station timing is detected, and after calculating the own station control channel, the operation shifts to the intermittent reception operation again. By controlling in this way, a call impossible state is avoided.
[0039]
DETAILED DESCRIPTION OF THE INVENTION
Next, a preferred embodiment of the present invention will be described in detail with reference to the drawings.
[0040]
FIG. 1 is a functional block configuration diagram showing an embodiment according to the present invention.
[0041]
Configuration of Embodiment
Referring to FIG. 1, a receiving apparatus according to an embodiment of the present invention uses a radio unit 10 for transmitting data, a synchronization detection unit 11 for synchronizing the data of a base station at a bit level, and use Display unit 12 for notifying the user of the status of an incoming call, etc., input unit 13 for the user to operate the mobile phone, transmission / reception data and display data, input data from the user, It comprises a storage unit 14 for holding the status and the like, and a CPU unit 15 for analyzing and creating the transmission / reception data, controlling the display unit, monitoring the change in the state of the input unit, and the like.
[0042]
[Operation of the embodiment]
Next, the operation of the embodiment according to the present invention will be described.
[0043]
First, a description will be given with reference to FIGS.
[0044]
A radio section format (TDMA system) used in a mobile phone will be described with reference to FIG.
[0045]
First, the super frame 21 is used as a reference in the radio channel, and this period is 720 ms. In this superframe 21, 36 subframes 22 are arranged. This subframe 22 has a period of 20 ms. Three units 23 are arranged in the subframe 22.
[0046]
The unit 23 is a minimum unit of received data, in which the burst transient response time 24 (hereinafter abbreviated as R) is 4 bits, the preamble 25 (hereinafter abbreviated as P) is 48 bits, the SW 26 is 20 bits, and a color code. 27 (hereinafter abbreviated as CC) is 8 bits, control signal 28 (hereinafter abbreviated as CAC) is 224 bits in total, and guard time 29 (hereinafter abbreviated as G) is 18 bits.
[0047]
Further, S1 to S3 and S7 to S9 described in FIG. 2 will be described with reference to FIG.
[0048]
Next, the 20-bit pattern of the synchronization word SW26 shown in FIG. 2 will be described with reference to FIG.
[0049]
S7 to S12 are synchronization words (SSW) 26 used in the unit 23 in the first subframe 22 of the superframe 21, and S7 to S9 (30) are used particularly in the radio channel when the PCH 43 is received. It has been.
[0050]
S1 to S6 are synchronization words (SW) 26 used in units other than the head unit of the superframe 21, and S1 to S3 (31) are used in the PCH reception radio channel as in the case of SSW. 2).
[0051]
It should be noted that when the time slot of the base station is detected using the SW26 pattern, the SW26 pattern repeats S1 to S3 (31) except for the unit 23 in the first subframe 22 of the superframe 21. However, if there is a timing shift in units of subframes for some reason, the mobile phone cannot detect the timing shift.
[0052]
FIG. 4 shows a basic configuration of the radio channel. FIG. 4 shows an example in which there are two radio channels NC in one zone.
[0053]
Referring to FIG. 4, first, a broadcast channel (hereinafter abbreviated as BCCH) 41, a dedicated cell channel (hereinafter abbreviated as SCCH) 42, and a general call channel (PCH) 43 will be described.
[0054]
The BCCH 41 is an information channel used to notify the mobile phone of basic configuration information of the radio channel shown in FIG.
[0055]
The SCCH 42 is a channel used when it is necessary to temporarily transmit and receive data of each mobile phone, such as during outgoing / incoming operations.
[0056]
The PCH 43 is a channel for receiving a call signal from the base station when the mobile phone transitions to a call waiting state from the base station, and the PCH 43 is a channel that is simultaneously received by a plurality of mobile phones. The mobile phone to be called is identified with the mobile station identifier MSI in the middle.
[0057]
In FIG. 4, B is abbreviated as BCCH, S is abbreviated as SCCH, and P is abbreviated as PCH.
[0058]
Next, NC44, NP45, AB46, AP47, AS1 (48), and AS2 (49), which are parameters for determining the basic configuration of the radio channel, will be described.
[0059]
NC44 represents the number of radio channels existing in one zone.
[0060]
NP45 represents the number of groupings of PCH43 existing in one radio channel.
[0061]
AB 46 represents the number of BCCHs 41 existing from the head of one superframe.
[0062]
AS1 (48) represents the number of SCCHs 42 arranged after BCCH41.
[0063]
AP 47 represents the number of PCHs 43 and is arranged subsequent to the SCCH 42.
[0064]
AS2 (49) represents the number of SCCHs 42 arranged between the PCH 43 and the next PCH 43.
[0065]
With these parameters, the mobile phone is notified of the placement of each information channel placed in the radio channel, and based on this, the mobile phone calculates its own PCH position and waits for a call from the base station. Transition to some intermittent reception.
[0066]
FIG. 5 is a diagram showing an example of the own station control channel shift operation (own station control channel selection operation example) based on the radio channel shown in FIG. 4 and the mobile station identifier MSI inside the mobile station.
[0067]
The mobile station identifier MSI is an individual identification number that contributes to each radiotelephone. Using MSI and NC 44 and NP 45 described in FIG. 4, self group control channel selection = standby time slot of own station is calculated.
[0068]
Further, the same calculation is performed in the base station, and the unit 23 in which the mobile phone receives the PCH 43 is a system that synchronizes between the base station and the mobile phone.
[0069]
The calculation formula used for calculation of the own group control channel is as follows.
[0070]
n = Decimal representation value of lower 2 octets of MSI (hexadecimal representation)
n ′ = (n−1) mod (NC × NP) +1
IF = (n′−1) mod NC + 1
IP = [(n′−1) / NC] +1
In this embodiment, the values calculated from the MSI and base station data are as follows.
[0071]
NC = 3 NP = 3 n = 9
When calculating using the above parameters, the following values are calculated.
[0072]
n ′ = 9 IF = 3 IP = 3
FIG. 6 is a timing chart for explaining the intermittent reception operation for receiving the PCH selected in FIG. 5 and reducing the operating current. This explanatory diagram shows the case where AP47 = 1.
[0073]
The mobile phone is designed to receive only the PCH 43 of its own group while waiting for a call from the base station. This is because the system does not need to receive the data of other units 23, and there is a merit that the current consumed can be reduced by not performing the receiving operation.
[0074]
FIG. 7 is a diagram showing a data format in the PCH network layer.
[0075]
The cellular phone compares the MSI in the PCH 43 data with the MSI of the own station to determine whether or not the call is for the own station. The MSI data is compared, and if it matches the MSI of the own station, it is assumed that a call has been made from the base station and the operation proceeds to a call operation or the like. If the received MSI and the MSI of the local station do not match, the intermittent reception operation described in FIG.
[0076]
2 to 6, the mobile phone shifts to an intermittent reception operation (see FIG. 6) that waits for a call from the base station.
[0077]
If a time slot error of the mobile phone occurs for some reason during the intermittent reception operation, the PCH transmission time slot of the base station and the PCH reception time slot of the mobile station do not match, and the call cannot be made.
[0078]
When the intermittent reception operation is started in the time slot of BCCH 41 or SCCH 42 that should not be received while waiting for a call, data other than PCH 43 can be received, so a time slot error can be detected, but the time slot that PCH 43 can receive is erroneous. If the expected pattern data of the SW 26 is received, the mobile phone cannot detect that the timing with the base station has shifted, and it is assumed that the reception time slot from the base station is not incorrect. Keep waiting for the call. As a result, the call cannot be made.
[0079]
Therefore, in the present invention, the calculation of the local station control channel performed when the mobile station enters the call waiting state in addition to whether the local station is called using the MSI in the PCH 43 received during the intermittent reception operation (see FIG. 5). ).
[0080]
Since the PCH 43 can be received by a plurality of mobile phones, the PCH 43 for other stations can also be received.
[0081]
Since NC44 and NP45 are parameters common to the radio channels, the local station originally receives the time slot position of PCH43 received by calculating the local station control channel using MSI (see FIG. 5). It is possible to determine whether or not it is a time slot. Further, since these processes are processes conventionally performed at the time of transition to the standby operation, the processes are easy.
[0082]
When a time slot error is detected, the timing of the base station is detected, and the self-station control channel is calculated. By controlling in this way, it is possible to avoid a call impossible state.
[0083]
Next, the operation of the embodiment according to the present invention will be described in more detail with reference to the flowcharts shown in FIGS.
[0084]
8 shows a synchronization process with the base and data reception processing flow, FIG. 9 shows a PCH reception timing determination processing flow, FIG. 10 shows a transition processing flow from BCCH reception to intermittent reception processing, and FIG. 11 calculates an expected value. FIG. 8 to FIG. 11 are continuous, and (1) to (5) are connected.
[0085]
[Synchronization processing with base and data reception processing]
First, in step S1 in FIG. 8, synchronization with the base is performed.
[0086]
Next, in step S2, the synchronization detection unit 11 in FIG. 1 searches the received data for the SW and SSW bit patterns.
[0087]
In step S3, it is determined whether or not the synchronization detection is completed.
[0088]
Next, if the result of determination in step S3 is Yes, that is, if synchronization detection is completed, data reception processing is performed in step S4, and CAC data is acquired in step S5.
[0089]
Next, the type of data acquired in step S6 is determined.
[0090]
As a result of the determination in step S6, if the acquired data type is BCCH, NC / NP is acquired from the received data in step S7 and stored in the storage unit 14 in FIG.
[0091]
In step S8, the MSI is acquired from the storage unit 14.
[0092]
As a result of the determination in step S6, if the acquired data type is PCH, NPC / NP is acquired from the storage unit 14 in step S7 ′, and MSI is acquired from the received data in step S8 ′. At the time of receiving the PCH, the MSI in the received data is used for comparison with an expected value (calculated from MSI / NC / NP in the storage unit of the mobile station).
[0093]
[PCH reception timing determination processing]
Next, referring to FIG. 9, the process proceeds to step S9 in FIG. 9, where n is calculated, that is, the lower 2 octets of the MSI are cut out and expressed in decimal.
[0094]
Subsequently, in step S10, step S11, and step S12, calculation of n ′ (intermediate value) by the following equation (1), calculation of IF by equation (2), and calculation of IP by equation (3), respectively.
n ′ = (n−1) mod (NC × NP) +1 (1)
IF = (n′−1) mod NC + 1 (2)
IP = [(n′−1) / NC] +1 (3)
mod: Remainder calculation operation after division
Execute.
[0095]
In step S13, the IF / IP is held in the storage unit 14 of FIG.
[0096]
Next, in step S14, it is determined which of BCCH / PCH is being processed.
[0097]
[Transition processing from BCCH reception to intermittent reception processing]
If the result of the determination in step S14 is that BCCH is being processed, the process proceeds to step S15 in FIG. 10, and in step S15, the current channel is compared with the IF calculated in step S11.
[0098]
If they match as a result of the comparison determination in step S15, the base timing is extracted from the synchronization detection unit 11 in step S16, and the timing extracted in step S17 and the IP calculated in step S12 are compared and determined.
[0099]
As a result of the comparison determination in step S17, if they match, the process proceeds to the intermittent reception process in step S18, the PCH reception process is started, and the process returns to step S4 in FIG.
[0100]
[Comparison of expected value and calculated IP]
As a result of the determination in step S14 in FIG. 9, in the case of PCH processing, the process proceeds to step S19 in FIG. 11, and the IP calculated in step S12 is acquired from the storage unit 14 in FIG.
[0101]
Next, in step S20, a comparison is made with the IP calculated from the PCH data.
[0102]
If the result of determination in step S20 is a match, the process proceeds to step S21. In this case, since the reception timing is not shifted, the intermittent reception process is performed, the PCH reception process is executed, and the process returns to step S4 in FIG. .
[0103]
As a result of the determination in step S20 in FIG. 11, if they do not match, the process proceeds to step S22, and the reception timing is shifted. Therefore, the process returns to step S1 in FIG. 8, and the timing adjustment process is performed again.
[0104]
As a result of the determination in step S6 in FIG. 8, in the case of PCH, NC / NP is acquired from the storage unit 14 in step S7 ′, and MSI is acquired from the received data in step S8 ′. In step S9, the same processing as described above is executed.
[0105]
[Other embodiments]
In the example of the embodiment of the present invention, a mobile phone has been described. However, if the following conditions are met, the present invention can be applied to other communication devices. CDMA communication equipment. These communication devices perform the following functions.
[0106]
Point-to-multipoint communication.
[0107]
Receive a call or other signal at regular intervals.
[0108]
There is identification data of the local station in the call signal from the other party.
[0109]
In the embodiment of the present invention, as shown in FIG. 7, the method of calculating the local station control channel by analyzing the received data of the PCH 43 is described. Similar control is possible if there are incoming signals. As a notification method in a mobile phone, it is possible to enter an MSI during the link layer format for notification.
[0110]
【The invention's effect】
The present invention is configured and operates as described above. According to the present invention, the following effects can be obtained.
[0111]
In the call waiting state of the mobile phone, it is possible to avoid a state where the call cannot be made.
[0112]
Since the existing control and calculation are performed in combination, the adaptation to the apparatus is easy.
[0113]
Since dedicated hardware is not required, adaptation to other devices is easy.
[0114]
In the present invention, the existing intermittent reception cannot recognize the timing shift in units of subframes, so that the incoming call cannot be received. However, in the present invention, even when the timing shift occurs, the timing shift can be detected and recovered. Features that can be obtained.
[Brief description of the drawings]
FIG. 1 is a functional block configuration diagram showing an embodiment according to the present invention.
FIG. 2 shows a time slot and PCH data format used in the present invention.
FIG. 3 shows a 20-bit sync word pattern.
FIG. 4 is a diagram illustrating a basic structure of a radio channel (an example in the case where the number of radio channels is two).
FIG. 5 is a diagram showing an example of operation for selecting a local control channel.
FIG. 6 is a timing chart for explaining an operation example of intermittent reception (an example in the case of AP = 1).
FIG. 7 is a diagram illustrating a data format in a network layer of PCH.
FIG. 8 is a flowchart showing a synchronization process with a base and a data reception process flow;
FIG. 9 is a flowchart showing a PCH reception timing determination processing flow.
FIG. 10 is a flowchart showing a transition process flow from BCCH reception to intermittent reception processing;
FIG. 11 is a flowchart illustrating a comparison processing flow between an expected value and a calculated IP.
[Explanation of symbols]
10 ... Radio part
11 ... Synchronization detector
12 ... Display section
13 ... Input section
14: Storage unit
15 ... CPU
21 ... Superframe
22 ... Subframe
23 ... Unit
24 ... Hearst transient response time
25 ... Preamble
26 ... Synchronization word SW
27 ... Color code (CC)
28 ... Control signal (CAC)
29 ... Guard time (G)
30, 31 ... synchronization word
43 ... PCH
44 ... NC
45 ... NP

Claims (1)

The mobile station identifier MSI in the general call channel PCH received during the intermittent reception operation is used to detect whether or not there is a call of the local station, and the number of radio channels NC in one zone when transitioning to a call waiting state PCH grouping number NP of the general call channel in one radio channel, the local station control channel is calculated using the MSI, and the time slot position of the received general call channel PCH is originally received by the local station It is determined whether it is a time slot that should be present, and when a time slot error is detected, the timing of the base station is detected. A method of avoiding the condition ,
A first processing step that executes synchronization processing and reception processing with the base station, a second processing step that is executed subsequent to the first processing step, and that executes PCH reception timing determination processing; The third processing step is executed subsequent to the processing step, and the transition processing from the BCCH reception to the intermittent reception processing is executed, and the expected value and the calculated IP comparison processing are executed subsequent to the third processing step. A fourth processing step of executing
The first processing step searches the received data for the bit pattern of the synchronization word SW and SSW in order to synchronize with the base, performs data reception processing after the completion of synchronization detection, and determines the CAC control signal from the received data. And the type of the acquired data is determined. As a result of the determination, when the broadcast channel is BCCH, the number of radio channels existing in one zone from the received data is NC / 1. Including the process of acquiring the grouping number NP of the local call channel PCH of the local station and holding it in the storage unit, and acquiring the mobile station identifier MSI from the storage unit,
As a result of determining the type of the acquired data, if it is a general call channel PCH of the own station, the number of radio channels existing in one zone from the storage unit NC / 1 the number of PCH groups existing in one radio channel NP is acquired, the mobile station identifier MSI is acquired from the received data,
The second processing step calculates n by cutting out the lower 2 octets of the mobile unit identifier MSI acquired from the storage unit and expressing it in decimal, and uses the NC and NP acquired from the MSI and received data. N ′ = (n−1) mod (NC × NP) +1 to calculate n ′, IF = (n′−1) mod NC + 1 to calculate IF, and IP = [(n′−1) / NC] +1 to calculate IP, and then hold IF / IP in the storage unit and determine whether BCCH / PCH is being processed,
As a result of determining whether BCCH / PCH is being processed, the third processing step is calculated according to the current channel and IF = (n′−1) modNC + 1 formula when BCCH is being processed. IF is compared and determined, and if the comparison results in coincidence, the base timing is extracted from the synchronization detection unit, and the timing and IP calculated by the equation IP = [(n′−1) modNC + 1 are compared and determined. And, if the result of the comparison determination is a match, includes a process of shifting to the intermittent reception process and starting the PCH reception process,
In the fourth processing step, as a result of determining whether BCCH / PCH is being processed in the second processing step, if the PCH is being processed, the IP calculated at the time of BCCH reception is obtained from the storage unit. Then, the IP and the IP calculated from the PCH data are compared and judged, and if the result of the comparison and judgment is the same, the reception timing is not shifted, so the process proceeds to the intermittent reception process, and the PCH reception process is continued.
When the IP calculated at the time of BCCH reception from the storage unit and the IP calculated from the PCH data are compared and determined to be inconsistent, the reception timing is shifted, so that the time is shifted to the timing adjustment process again. How to avoid call failure due to slot error.

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