JP2006211016A - Mobile communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent efficient use of radio waves because radio base stations that cannot receive a synchronization signal from a network cannot establish synchronization in a radio section.
SOLUTION: A plurality of radio base stations (general type radio base station 1, IP connection type radio base station 10, digital cordless base unit 2) having different system types, and a slave unit 5A for radio connection to the plurality of radio base stations. 5B and a TDMA mobile communication system 100 having a private branch exchange 4 that is wired to the radio base station, wherein the radio base station is a reference radio base station (reference station) according to a preset synchronization mode. A frame signal including a control CH signal is received from the receiver, and the reception timing of the own station is aligned with the transmission position of the control CH signal in the frame signal, and frame synchronization in the radio section between the own station and the reference station is established. did.
[Selection] Figure 1

Description

  The present invention relates to a plurality of radio base stations having different interface types with a control device, for example, a general radio base station of a PHS radio base station, an IP connection type radio base station, or a digital cordless base unit, and the plurality of radio base stations. The present invention relates to a mobile communication system of, for example, a time division multiple access (hereinafter simply referred to as TDMA) system, which has a wireless slave unit wirelessly connected to a station and establishes frame synchronization in a wireless section between wireless base stations.

  Conventionally, as such a TDMA type mobile communication system, a general wireless base station, a digital cordless base unit, and a private branch exchange equipped with a control device for controlling the general type wireless base station and the digital cordless base unit, A wireless slave device that is wirelessly connected to a general-type wireless base station and a digital cordless slave device that is wirelessly connected to a digital cordless master device, and the wireless slave device can be connected for communication through the general-type wireless base station The digital cordless slave can be connected for communication through the digital cordless master (see, for example, Patent Document 1).

  FIG. 23 is a block diagram showing a schematic configuration inside a conventional TDMA type mobile communication system.

  A mobile communication system 200 shown in FIG. 23 is disposed in a private area such as an office or a factory for private use, and is generally connected through a plurality of general radio base stations 1, a plurality of digital cordless master units 2 for offices, and an ISDN line 3. A private branch exchange 4 having a control device for communication connection with the digital wireless base station 1 and a communication connection with the digital cordless base unit 2, and a wireless slave unit (hereinafter simply referred to as a slave unit) for wireless connection with the general type wireless base station 1 5A and a digital cordless slave unit (hereinafter simply referred to as a slave unit) 5B wirelessly connected to the digital cordless master unit 2.

  The general wireless base station 1 and the digital cordless base unit 2 execute a call control procedure in the wireless section based on the RCR standard that is the Radio Industry Association (ARIB) standard, and the slave unit 5A and the slave unit 5B Services such as voice calls and data communications can be provided.

  Further, in the RCR standard, for example, the communication frequency band between the handset 5A and the general radio base station 1, the carrier number, and the information structure of the control CH signal as a call control signal used for frame synchronization are defined. Yes. However, since the control CH signal is commonly allocated in the mobile communication system of the same method, there is an obligation to avoid radio wave interference with other systems of the same method.

  For example, if the general radio base stations 1 (1A, 1B) in the same system transmit radio waves at arbitrary timings and the radio waves interfere with each other, the use efficiency of the radio waves decreases. Therefore, in order to prevent a decrease in radio wave use efficiency, the general radio base stations 1 (1A, 1B) are combined with the radio transmission timing of the TDMA-TDD frame between the general radio base stations 1 (1A, 1B). It is necessary to ensure frame synchronization.

  FIG. 24 is an explanatory diagram showing the concept of a TDMA-TDD frame used in a radio section of a TDMA type mobile communication system.

  A TDMA-TDD frame 300 shown in FIG. 24 is a slot configuration of a radio section of the second generation cordless telephone system standard standardized by ARIB, and one slot as a minimum unit is configured by 240 bits (625 μs), and 8 One frame (5 ms) is used for the slot.

  One slot 310 includes a 4-bit transient response ramp time 311, 220-bit control information data 312, and 16-bit guard bits 313, and guard bits (16 Bit) 313 and transient response ramp time (4 bits) 311, which is a total of 20 bits, that is, up to 52.1 μs is a tolerance for absorbing a shift between slots.

  Also, when the general wireless base stations 1 (1A, 1B) are in the frame synchronization state, as shown in FIG. 24, the TDMA-TDD frames of the general wireless base station 1A and the general wireless base station 1B are the same. This is a state in which radio waves are transmitted at the timing. In order to maintain these synchronization states, it is necessary to keep the amount of deviation between the TDMA-TDD frame of the general radio base station 1A and the TDMA-TDD frame of the general radio base station 1B within an allowable range.

  Next, the operation until the conventional general radio base stations 1 ensure frame synchronization will be described.

  Each general-type radio base station 1 receives a synchronization signal serving as a frame synchronization reference through the ISDN line 3 of the private branch exchange 4, and matches the transmission timing of the TDMA-TDD frame with the received synchronization signal, so that the general-type radio Frame synchronization between the base stations 1 (1A, 1B) is established.

  Also, according to the conventional TDMA mobile communication system 200, when frame synchronization between the general radio base stations 1 (1A, 1B) is established, it is necessary to determine the timing for transmitting the control CH signal. The transmission position of the control CH signal needs to be controlled so that the general radio base stations 1 (1A, 1B) do not overlap each other.

  Therefore, the control CH signal transmission position sorting process for controlling the transmission positions of the control CH signals so as not to overlap between general wireless base stations 1 will be described. FIG. 25 is an explanatory diagram conceptually showing a general control CH transmission cycle.

  The control CH transmission cycle shown in FIG. 25 is a cycle of 1 frame of 5 ms for N frames (25 ≦ N ≦ 60). That is, each general radio base station 1 has 1 to N in this N interval cycle. The control channel signal of the own station is transmitted at an arbitrary frame position. Also, a multiplexed frame of N frames is called a super frame.

  For example, when the general radio base station 1A transmits the control CH signal at the timing “1”, the transmission timing of the next control CH signal is the control CH signal transmitted at the timing “N + 1”. That is, each general radio base station 1 transmits its own control CH signal once every N intervals.

  Since the general-type radio base station 1 uses its own control CH signal in order of start-up completion when the power is turned on or the like, the transmission position of its own control CH signal is notified within the interval range. In the general radio base station 1 that rises from the base station, the control CH signal between the general radio base stations 1 is avoided based on the broadcast information, avoiding the transmission position of the control CH signal used by the other general radio base stations 1. The transmission position of the control CH signal of the own station is determined within the same interval range so that the transmission positions of the signals do not overlap.

  According to the conventional TDMA type mobile communication system 200 as described above, the synchronization signal is distributed from the private branch exchange 4 to each general radio base station 1 through the ISDN line 3. -Frame synchronization between general-type wireless base stations 1 under the same system can be established by adjusting the transmission timing of the TDD frame.

  Further, according to the conventional TDMA type mobile communication system 200, when frame synchronization between the general radio base stations 1 is established, it does not overlap with the transmission position of the control CH signal of the other general radio base stations 1. The control CH signal transmission position used by the local station is searched within the interval range, and the service operation is started after the transmission position of the control CH signal is determined.

Further, according to the conventional TDMA type mobile communication system 200, since the digital cordless master unit 2 has a one-to-one direct communication method with respect to the slave unit 5, it is synchronized with other general radio base stations 1. Instead, radio waves are transmitted at the self-running timing.
JP 2001-145155 A (refer to paragraph numbers “0001” to “0004”)

  However, according to the conventional TDMA mobile communication system 200, after establishing frame synchronization between the general radio base stations 1 (1A, 1B) using the synchronization signal from the private branch exchange 4, the general radio base station The segregation control is performed so that the control CH signal transmission positions of the stations 1 (1A, 1B) do not overlap. For example, in the case of an IP connection type radio base station connected to the private branch exchange 4 through a LAN line, In order to ensure synchronization in the wireless section with the wireless base station 1, it is possible to transmit the synchronization signal from the private branch exchange 4 to each IP connection wireless base station by using a data packet. Data packet delays and fluctuations occur on the LAN line, and all IP connection type radio base stations cannot receive the synchronization signal at the same timing, and the IP connection type radio base station It is not possible to establish synchronization in the radio section between the IP connection type radio base station and the general type radio base station 1 as well as the master, and accordingly, segregation control for determining the transmission position of the control CH signal is also executed. It is not possible to ensure efficient and efficient use of radio waves.

  Also, according to the conventional TDMA mobile communication system 200, since the digital cordless master unit 2 uses a one-to-one direct communication method with respect to the slave unit 5B, it is synchronized with other general-type radio base stations 1. However, since the digital coreless base unit 2 and the general wireless base station 1 use the same frequency band, for example, a service that operates the general wireless base station 1 is used. When the digital cordless master unit 2 is arranged in the area, the slave unit 5B is affected by the radio waves of the general type radio base station 1 and the digital cordless master unit 2 in the vicinity. There is a high possibility of radio wave interference between the wireless base station 1 and the digital cordless base unit 2, and as a result, the service quality may be degraded.

  The present invention has been made in view of the above points. The object of the present invention is to establish synchronization in a wireless section even between wireless base stations of different system types, and to efficiently use radio waves. An object of the present invention is to provide a mobile communication system capable of ensuring and greatly improving service quality.

  In order to achieve the above object, a mobile communication system of the present invention is a mobile communication system having a plurality of radio base stations of different system types, and a radio slave unit wirelessly connected to the plurality of radio base stations, The radio base station receives a frame signal including a control CH signal from the radio base station serving as a reference for frame synchronization selected from among the plurality of radio base stations other than the own base station according to a preset synchronization mode. The reception timing of the own station is matched with the transmission position of the control CH signal in the frame signal, and frame synchronization in the radio section between the own station and the reference radio base station is established.

  The mobile communication system of the present invention is a public base station synchronous mobile communication system in which the reference radio base station corresponds to a public base station synchronized with a public network, and the radio base station is preset. In accordance with the synchronization mode, a frame signal including a control CH signal is received from the reference radio base station, and the reception timing of the own station is adjusted to the transmission position of the control CH signal in the frame signal, Frame synchronization in the wireless section with the reference wireless base station is established.

  The mobile communication system of the present invention is a direct synchronous mobile communication system in which the reference radio base station corresponds to a radio base station synchronized with a private branch exchange, and the radio base station has a preset synchronization mode. And receiving the frame signal including the control CH signal from the reference radio base station, and adjusting the reception timing of the own station to the transmission position of the control CH signal in the frame signal, and the own station and the reference The frame synchronization in the wireless section with the wireless base station is established.

  The mobile communication system according to the present invention is a public base station in which the reference radio base station uses a radio base station that has established frame synchronization in a radio section as a reference to the public base station synchronized with the public network. In the indirect synchronous mobile communication system, the radio base station receives a frame signal including a control CH signal from the reference radio base station in accordance with a preset synchronization mode, and the control CH in the frame signal The reception timing of the local station is matched with the signal transmission position, and frame synchronization is established in a wireless section between the local station and the reference wireless base station.

  The mobile communication system of the present invention is a direct synchronous mobile communication system in which the reference radio base station corresponds to a radio base station synchronized with a private branch exchange, and the radio base station has a preset synchronization mode. The frame signal including the control CH signal is received from the reference radio base station, and the control in the frame signal is performed only when the identification ID of the base station has the identification ID that the own station should be the reference station. The reception timing of the own station is matched with the transmission position of the CH signal, and frame synchronization in the radio section between the own station and the reference radio base station is established.

  According to the mobile communication system of the present invention configured as described above, control is performed from a radio base station serving as a reference for frame synchronization selected from among a plurality of radio base stations other than the own station, according to a preset synchronization mode. A frame signal including a CH signal is received, the reception timing of the own station is matched with the transmission position of the control CH signal in the frame signal, and frame synchronization is performed between the own station and the reference radio base station. Since frame synchronization is established in the wireless section, for example, a general wireless base station connected to a private branch exchange via an ISDN line, an IP connection wireless base station connected to a private branch exchange connected via a LAN line, and a digital cordless base unit Even when different types of wireless base stations are established, synchronization is established in the wireless section, and the transmission position of the control CH signal after synchronization is established is determined. By implementing split control at a waiting time that absorbs the time difference between startups by synchronous control, it is possible to ensure efficient use of radio waves and prevent radio wave interference between radio base stations, greatly improving service quality. Can be achieved.

  Furthermore, according to the mobile communication system of the present invention, when receiving a control CH signal from a reference radio base station during service operation, the reception timing of the own station is set at the transmission position of the control CH signal in this frame signal. In addition, since frame synchronization in the wireless section between the reference wireless base station and the own station is established, in the stopped state when receiving the control CH signal from the reference wireless base station There is no instantaneous interruption of the line, and as a result, the call quality can be greatly improved.

  According to the mobile communication system of the present invention, even if the reference radio base station is a public base station synchronous mobile communication system corresponding to a public base station synchronized with a public network, the radio base station According to the set synchronization mode, a frame signal including a control CH signal is received from the reference radio base station, and the reception timing of the own station is matched with the transmission position of the control CH signal in the frame signal, Since the frame synchronization in the wireless section between the station and the reference wireless base station is established, even if different types of wireless base stations are in the wireless section in the public base station synchronous mobile communication system, By implementing segregation control that establishes synchronization and determines the transmission position of the control CH signal after synchronization is established at a waiting timing that absorbs the time difference of activation by synchronization control, While securing the rate effectiveness use can prevent radio interference between the wireless base station, it is possible to greatly improve the service quality.

  Furthermore, according to the mobile communication system of the present invention, when a control CH signal is received from a reference radio base station during service operation in a public base station synchronous mobile communication system, the control CH signal in this frame signal is received. In the public base station synchronous mobile communication system, frame synchronization in the wireless section between the base station and the base station is established by matching the reception timing of the base station with the transmission position of the base station. When the control CH signal is received from the reference radio base station, there is no instantaneous interruption of the line in the wave-stopping state, and as a result, the call quality can be greatly improved.

  According to the mobile communication system of the present invention, even if the reference radio base station is a direct synchronization type mobile communication system corresponding to a radio base station synchronized with a private branch exchange, the radio base station is set in advance. In accordance with the synchronization mode, a frame signal including a control CH signal is received from the reference radio base station, and the reception timing of the own station is adjusted to the transmission position of the control CH signal in the frame signal, Since frame synchronization is established in the wireless section with the reference wireless base station, synchronization is established in the wireless section even between different types of wireless base stations in the direct synchronization type mobile communication system. By implementing the segregation control for determining the transmission position of the control CH signal after the synchronization is established at a waiting timing that absorbs the time difference of activation by the synchronization control, While ensuring efficient use, prevents radio wave interference between the wireless base station, it is possible to greatly improve the service quality.

  Furthermore, according to the mobile communication system of the present invention, when a control CH signal is received from a reference radio base station during service operation in a direct synchronous mobile communication system, the control CH signal in this frame signal is transmitted. The frame synchronization in the radio section between the base station and the base station is established by matching the reception timing of the base station with the position, so that the base radio in the direct synchronization type mobile communication system There is no instantaneous interruption of the line in the wave-stopped state when receiving the control CH signal from the base station, and as a result, the call quality can be greatly improved.

  According to the mobile communication system of the present invention, the public base station indirect synchronization type mobile corresponding to the radio base station in which the reference radio base station establishes frame synchronization in the radio section with the public base station synchronized with the public network. Even in a communication system, the radio base station receives a frame signal including a control CH signal from the reference radio base station according to a preset synchronization mode, and transmits a control CH signal in the frame signal. Since the reception timing of the own station is matched with the position, and frame synchronization is established in the radio section between the own station and the reference radio base station, the public base station indirect synchronization type mobile communication system Even if there are different types of radio base stations, synchronization is established in the radio section, and the segregation control for determining the transmission position of the control CH signal after the synchronization is established By performing at a waiting time to yield, while ensuring an efficient effective utilization of radio waves, it is possible to prevent interference between the radio base station, it is possible to greatly improve the service quality.

  Furthermore, according to the mobile communication system of the present invention, when receiving a control CH signal from a radio base station serving as a reference during service operation in a public base station indirect synchronization mobile communication system, the control CH in this frame signal is received. Since the synchronization timing of the local station and the local station are established by matching the reception timing of the local station with the signal transmission position, public base station indirect synchronization type mobile communication In the system, there is no instantaneous interruption of the line in the wave-stopped state when receiving the control CH signal from the reference radio base station, and as a result, the call quality can be greatly improved.

  According to the mobile communication system of the present invention, even if the reference radio base station is a direct synchronous mobile communication system corresponding to a radio base station synchronized with a private branch exchange, the radio base station is set in advance. In accordance with the synchronization mode, a frame signal including a control CH signal is received from the reference radio base station, and only when the identification ID of the base station has an identification ID that the own station should be a reference station, Since the reception timing of the own station is matched with the transmission position of the control CH signal and frame synchronization is established in the radio section between the own station and the reference radio base station, direct synchronization mobile communication Even when different types of radio base stations in the system establish synchronization in the radio section, and start segregation control that determines the transmission position of the control CH signal after establishment of synchronization by synchronization control By performing at a waiting time to absorb the difference, while ensuring an efficient effective utilization of radio waves, it is possible to prevent interference between the radio base station, it is possible to greatly improve the service quality.

  In addition, since it is possible to design a system that clarifies the master-slave relationship of synchronization in the reference station, sub-reference station, and slave station, it is possible to grasp which reference station or sub-reference station the slave station is operating in synchronization with the failure of the reference station. Even if the slave station becomes unable to synchronize with the reference station, the faulty reference station can be easily identified and the maintainability of the system can be improved.

  Hereinafter, a TDMA mobile communication system according to an embodiment of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a block diagram showing a schematic configuration inside a TDMA mobile communication system according to the first embodiment. The same components as those in the TDMA mobile communication system 200 shown in FIG. 23 are denoted by the same reference numerals, and the description of the overlapping configuration and operation is omitted.

  A TDMA type mobile communication system 100 shown in FIG. 1 includes a plurality of general wireless base stations 1, a plurality of IP connection wireless base stations 10, a plurality of digital cordless base units 2, and an ISDN line 3. A private branch exchange 4 having a control device for communication connection with the base station 1, communication connection with the IP connection type radio base station 10 through the LAN line 6 and communication connection with the digital cordless base unit 2, and a general type radio base station 1 and a handset 5A that is wirelessly connected to the IP connection type wireless base station 10, and a handset 5B that is wirelessly connected to the digital cordless base unit 2.

  In the private branch exchange 4, it is assumed that a plurality of IP connection type wireless base stations 10 are connected to a LAN line 6 via a switching HUB 7.

  These general type radio base station 1 and IP connection type radio base station 10 perform the same call control procedure in the radio section based on the RCR STD-28 standard which is the ARIB standard. It is possible to provide services such as a telephone call and data communication by the wireless communication method.

  That is, the slave unit 5A does not identify the general type radio base station 1 and the IP connection type radio base station 10, and any general type radio base station 1 or IP connection type radio base station 10 arranged in the same system. Communication with is possible.

  FIG. 2 is a block diagram showing a schematic configuration inside the IP connection type radio base station 10.

  The IP connection type radio base station 10 shown in FIG. 2 has a radio function block 20 and a LAN function block 30.

  The radio functional block 20 includes two antennas 20A that transmit and receive radio waves, an antenna switching unit 21 that switches between the two antennas 20A, a transmission unit 22 that transmits radio waves, a reception unit 23 that receives radio waves, and a transmission A synthesizer unit 24 that generates a frequency used by the unit 22 and the reception unit 23, a modem unit 25 that modulates or demodulates data, a TDMA-TDD processing unit 26 that converts the data into a TDMA-TDD frame, and a radio functional block 20 An information notification unit 27 such as an LCD or LED that notifies various information, a wireless function memory unit 28 that stores various contents related to the wireless function block 20, and a wireless side CPU 29 that controls the entire wireless function block 20 Have.

  The LAN function block 30 includes a wireless interface unit 31 that controls an interface with the wireless function block 20, a DSP 32 that performs packet processing of voice data received on both the wireless side and the LAN side, and ADPCM that compresses and decompresses 32k ADPCM voice data. A codec 33, a LAN function memory unit 34 for storing various information related to the LAN function block 30, a LAN interface function for communication connection with the LAN line 6, and a LAN side CPU 35 for controlling the LAN function block 30; The power supply unit 36 supplies power to both the functional block 20 and the LAN functional block 30.

  First, points of the TDMA type mobile communication system 100 showing the first embodiment will be described. FIG. 3 is an explanatory diagram simply showing a system configuration (multilayer type) of the TDMA type mobile communication system 100 according to the first embodiment.

  First, the point of the mobile communication system 100 is that synchronization is established in the radio section among the general type radio base station 1, the IP connection type radio base station 10, and the digital cordless base unit 2.

  In this multi-layered mobile communication system 100, for example, the general type radio base station 1 is set as a reference station 1A, and the reference station 1A includes, for example, a first slave station of a child such as the IP connection type radio base station 10 or the digital cordless base unit 2 10A (including a sub-reference station described later) and the first slave station 10A are configured to wirelessly connect, for example, a second slave station 10B that is a grandchild such as the IP connection type radio base station 10 or the digital cordless base unit 2.

  The first slave station 10A receives the radio wave from the reference station 1A, and sets the radio wave transmission timing (TDMA-TDD frame transmission timing) of the local station 10A at the radio wave transmission timing (TDMA-TDD frame transmission timing) of the reference station 1A. In addition, the radio wave of the local station 10A is transmitted. That is, the radio wave transmission timing of the first slave station 10A matches the radio wave transmission timing of the reference station 1A as shown in FIG. 16C, and the radio wave reception timing of the first slave station 10A matches the radio wave reception timing of the reference station 1A. ing.

  Further, as time elapses, as shown in FIG. 16A, a time lag occurs between the radio wave transmission timing of the reference station 1A and the radio wave transmission timing of the first slave station 10A. Therefore, the deviation must be corrected periodically. Don't be.

  Therefore, in order to match the radio wave transmission / reception timing of the first slave station 10A with the radio wave transmission / reception timing of the reference station 1A, it is necessary to receive the radio wave transmitted by the reference station 1A and to synchronize with the radio wave and transmit the radio wave of the local station. There is.

  For this reason, as shown in FIG. 16B, the slave station 10A that normally transmits and receives radio waves in accordance with the reference station 1A switches the transmission process to the reception process (reception mode) at a predetermined cycle, and Is trying to receive the radio waves that are being transmitted. Timing is synchronized with the received transmission wave of the reference station 1A, and synchronization is achieved by transmitting the radio wave of the own station.

  Since the transmission of radio waves is stopped and switched to reception processing at the time of processing that should originally transmit radio waves, this state is called a stopped state.

  Further, the second slave station 10B receives the radio wave of the first slave station 10A, matches the radio wave transmission timing of the local station 10B with the radio wave transmission timing of the first slave station 10A, and transmits the radio wave of the local station 10B. That is, the radio wave transmission timing of the second slave station 10B matches the radio wave transmission timing of the first slave station 10A as shown in FIG. 16C, and the radio wave reception timing of the second slave station 10B is the same as that of the first slave station 10A. It will be adjusted to the reception timing.

  In this way, the radio wave transmission timing of the first slave station (IP connection type radio base station) 10A is matched with the radio wave transmission timing of the reference station 1A, and the second slave station (IP connection type radio base station) is synchronized with the radio wave transmission timing of the first slave station 10A. Station) 10B radio wave transmission timing is sequentially matched to ensure synchronization in the wireless section among the general type wireless base station 1, the IP connection type wireless base station 10, and the digital cordless base unit 2.

  By setting the reference station serving as a reference for radio synchronization to the general type radio base station 1, even if there are a plurality of general type radio base stations 1 in the same system, the general type radio base station 1 is connected to the private branch exchange 4. Since the radio wave is transmitted in synchronization with the synchronization signal from the mobile phone, no matter what type of radio base station 1 radio wave transmission timing is set, the same timing can be obtained, so there is no problem. .

  In addition, in the case of the IP connection type radio base station 10C having a single arrangement in which the radio area does not directly overlap with other radio base stations, an arbitrary radio wave transmission timing is set by setting an operation mode (self-running mode) described later. In some cases, radio wave transmission may be performed, and it is possible to operate in an asynchronous state.

  In addition, even if synchronization is established between the general type radio base station (reference station) 1A and the IP connection type radio base station (first slave station) 10A, the radio wave received as the synchronization signal is actually the IP connection type radio base station. Although 10 uses a highly accurate timing clock, a deviation within a certain range occurs in the hardware of the built-in circuit.

  When such a shift occurs in both of the IP connection type radio base station (first slave station) 10A on the side synchronized with the general type radio base station (reference station) 1A, for example, the TDMA of the general type radio base station 1A, for example A timing shift between the TDD frame and the TDMA-TDD frame of the IP connection type radio base station 10A occurs with time on the time axis.

  Therefore, in order to cope with such a situation, in order to ensure stable operation by radio synchronization, to which radio base station synchronization can ensure the most stable operation state, and the stable state of the entire system Therefore, it is necessary to perform a control related to synchronization control and control to keep the synchronization state even after the system starts operating.

  Furthermore, a synchronization state cannot be maintained due to a failure of a synchronization-destination wireless base station in operation or radio wave interference from a wireless base station or a repeater of another system, and processing when a loss of synchronization is caused is also necessary. Therefore, specific processing contents for dealing with this situation will be described below.

  First, the general-type radio base station 1, the IP connection type radio base station 10 and the digital cordless base unit 2 have various radio synchronizations that define the conditions of the synchronization-destination radio base station in order to ensure stable operation by radio synchronization. The conditions are set. FIG. 4 is an explanatory diagram briefly showing the contents of the wireless synchronization condition.

  The radio synchronization condition shown in FIG. 4 includes a call code indicating a radio base station (general type radio base station 1, IP connection type radio base station 10 and digital cordless base unit 2) in the same system group, There are three conditions: a reception level specification indicating a threshold level for determining whether or not the reception level between stations is good, and an individual own station additional ID assigned to each radio base station. The call code and the local station additional ID are identification IDs for identifying the radio base station.

  The call code recognizes that it is a radio base station in the same system group when the call codes match.

  The reception level regulation determines that the reception level between radio base stations is equal to or higher than the threshold level, and that the reception level with the radio base station is good, and the stability of periodic radio wave reception in synchronous operation This is a condition for ensuring operation.

  The self-station additional ID is assigned to each radio base station in consideration of the arrangement of devices in the actual service area of the radio base station (general type radio base station 1, digital cordless base unit 2, and IP connection type radio base station 10). For example, the general wireless base station 1 that can obtain a stable synchronization signal from the private branch exchange 4 is assigned a small number, and the digital cordless base station 2 and the IP connection close to the general wireless base station 1 are assigned. Numbers are assigned in the order in which the wireless base stations 10 are arranged. That is, in the physical arrangement of the radio base stations, the reference radio base station is set as the youngest additional ID, and other IP connection type radio base stations 10 synchronized with the radio base station have a higher number. For example, the IP connection type radio base station 10 physically located far away from the base radio base station as a reference is placed so that the additional ID has a larger number.

  Comparing the additional ID of the own station and the additional ID of the radio base station, and selecting the same radio base station as the synchronization target radio base station when the additional ID of the radio base station is smaller than the additional ID of the own station is there.

  That is, it can be determined that the conditions of the synchronization destination radio base station are satisfied when all the radio synchronization conditions such as the call code, the reception level specification, and the own station additional ID are satisfied.

  Further, when the system is started, an IP connection type radio base station 10 arranged in the vicinity of the reference type general radio base station 1 starting from the reference type radio base station, for example, the general type radio base station 1 is used. The wireless synchronization operation is started in order, and the startup sequence is such that the far-end IP connection type wireless base station 10 and the digital cordless master unit 2 operate synchronously last.

  As a result, the entire system forms a pyramid-shaped multi-layer wireless synchronization having the reference station 1A as a vertex as shown in FIG. 3, so that the synchronization state can be easily grasped. In addition, even when out-of-synchronization occurs and the self-running mode is entered, other radio base stations that are based on the radio base station where the out-of-synchronization has occurred by continuing to transmit radio waves at the timing before the out-of-synchronization occurs ( (Slave station) can continue the synchronous operation, and can partially limit the range of influence. Furthermore, recovery from the out-of-synchronization state can be performed autonomously and partially without affecting the entire system.

  The general type radio base station 1, the IP connection type radio base station 10, and the digital cordless base unit 2 have individual setting information related to radio synchronization control. FIG. 5 is an explanatory diagram briefly showing the contents of individual setting information related to wireless synchronization control.

  The setting information shown in FIG. 5 is assumed to be stored in the designated address of the built-in ID-ROM inside each general type radio base station 1, IP connection type radio base station 10, and digital cordless base unit 2.

  The setting information shown in FIG. 5 includes a reference timer time (timer unit) that is a parameter for the start mode time for starting the segregation control for determining the operation mode set for the own station and the transmission position of the control CH signal of the own station. And the lower effective number of bits of the additional ID of the own station, and the synchronous retry control execution time for executing the synchronous retry control which is a maintenance function of the wireless synchronization control described later of the own station.

  The operation mode is a self-running mode that outputs radio waves at any radio wave transmission timing of its own station, and outputs radio waves after establishing radio synchronization between its own station and the reference radio base station, that is, to other radio base stations There is a synchronization mode for wireless synchronization.

  The reference timer time is set between 0 and 60 seconds, the number of lower significant bits of the additional ID is set between 00 and 04, the reference timer time is 30 seconds, and the number of lower significant bits is “4”. The divided waiting timing time is 30 seconds × 4, 120 seconds. The number of lower significant bits of the additional ID corresponds to the group number.

  The synchronous retry control execution time is set between 00 and 23:00. For example, if it is set at 2 am, it is “02”. When the synchronous retry execution time is set to a value other than “00 to 23”, for example, XX, it is assumed that no time is set for the synchronous retry control execution time.

  The wireless synchronization conditions shown in FIG. 4 and the setting information shown in FIG. 5 can be arbitrarily changed by a command operation from a maintenance terminal connected to the control device of the private branch exchange 4, for example.

  The mobile communication system described in the claims corresponds to the TDMA mobile communication system 100, and the radio base station corresponds to the general radio base station 1, the IP connection radio base station 10, and the digital cordless base unit 2. .

  Next, the operation of the TDMA mobile communication system 100 showing the first embodiment will be described. Note that the software control shown in each flowchart regarding the wireless synchronization control described in the first embodiment is based on the independent standard system established in the ARIB second generation cordless telephone system standard (RCR STD-28 standard). This is done in accordance with the communication control method. Further, for convenience of explanation, the reference station is assumed to be a general radio base station 1 and the radio base station (slave station) that is radio-synchronized with the reference station is assumed to be an IP connection type radio base station 10.

  FIG. 6 is a flowchart showing processing operations related to the wireless synchronization control processing of the IP connection type wireless base station 10.

  The wireless synchronization control process shown in FIG. 6 starts up the power supply of the IP connection type wireless base station 10 and performs various processes until the IP connection type wireless base station 10 operates the self-running mode service or the synchronous mode service. In addition, it has a maintenance function for stabilizing the service operation.

  In FIG. 6, when the power is turned on (step S11), the wireless CPU 29 of the IP connection type wireless base station 10 executes an internal software initialization process (step S12), and then the internal ID-ROM (wireless) shown in FIG. The operation mode set in the function memory unit 28), that is, the operation mode setting of the own station is confirmed (step S13).

  When it is determined in step S13 that the operation mode is the synchronization mode “01”, the wireless CPU 29 searches for nearby wireless base stations and sends out the control CH signal of the detected synchronization destination candidate wireless base station. A control CH signal scanning process for scanning the position is executed (step S14). This control CH signal scanning process is a process for detecting the transmission position of the control CH signal in the interval range of the control CH transmission cycle shown in FIG.

  The radio side CPU 29 is a synchronization destination candidate radio base that simultaneously satisfies the radio synchronization condition shown in FIG. 4 within the interval range of the control CH transmission cycle shown in FIG. 7 during the control CH signal scan processing in step S14. It is determined whether or not the control CH signal of the station has been detected (step S15).

  If the control CH signal is not detected in step S15, the radio side CPU 29 determines whether or not the detection execution time Tx for detecting the control CH signal has elapsed (step S16). Note that the detection execution time Tx starts the time measuring operation when the control CH signal scanning process is activated.

  If the detection execution time Tx has elapsed, the radio side CPU 29 detects the control CH signal of the radio base station that is the synchronization destination candidate that simultaneously satisfies the radio synchronization conditions shown in FIG. 4 within the detection execution time Tx. Therefore, it is determined that the wireless synchronization has failed, and the operation in the self-running mode service is forcibly started (step S17). In the self-running mode service, the segregation control process is executed to determine the transmission position of the control CH signal of the local station at an arbitrary radio timing of the local station without synchronizing with other radio base stations. In this way, the service operation in the self-running mode is started.

  If the detection execution time Tx has not elapsed in step S16, the radio side CPU 29 proceeds to step S15 in order to detect the control CH signal of the synchronization destination candidate radio base station within the interval range.

  If the radio side CPU 29 detects the transmission position of the control CH signal of the radio base station that is the synchronization destination candidate in step S15, the radio side CPU 29 sets the control CH signal of the radio base station that is the synchronization destination candidate to the transmission position of the own station. A control CH alignment process for adjusting the transmission position of the control CH signal is executed (step S18). This control CH positioning process is a process for matching the timings of the TDMA-TDD frame of the synchronization target candidate radio base station and the TDMA-TDD frame of the local station.

  In step S18, the wireless side CPU 29 matches the transmission destination of the control CH signal of the synchronization destination candidate radio base station and the own station, and then measures the amount of time deviation from the synchronization destination control CH signal for each specified period. Then, a basic deviation amount measurement process is performed in which the basic deviation amount data is added to the basic deviation amount accumulation counter as basic deviation amount data in bit units (step S19).

  After executing the control CH signal scan process in step S14, the control CH alignment process in step S18, and the basic deviation amount measurement process in step S19, the radio side CPU 29 performs frame synchronization between the radio base station that is the synchronization destination and its own station. To establish.

  After executing the basic deviation amount measurement process in step S19, the radio side CPU 29 executes a segregation start waiting process for the control CH signal transmission position of the local station (step S20). In this segregation start waiting process, the start timing of segregation control for determining the transmission position of the control CH signal of the own station is shifted in time, and thereafter the transmission position of the control CH signal of the other radio base station. In this process, the transmission position of the control CH signal of the own station is determined as an optimal transmission position.

  When the segregation start waiting process is completed in step S20, the radio side CPU 29 completes all processes related to radio synchronization control, and monitors and synchronizes the synchronization destination radio base station in order to maintain the synchronization operation state. The service operation in the wireless synchronization mode is started while continuing the deviation correction process (step S21).

  On the other hand, if it is determined in step S13 that the operation mode is the free-running mode “00”, the wireless-side CPU 29 does not perform wireless synchronization control such as a single arrangement in which radio waves do not overlap with other wireless base stations. The operation using the mode service is started (step S22). In the self-running mode service, the segregation control process is executed to determine the transmission position of the control CH signal of the local station at an arbitrary radio timing of the local station without synchronizing with other radio base stations. In this way, the service operation in the self-running mode is started.

  In addition, during the self-running mode service in step S17 due to a failure in wireless synchronization, the wireless CPU 29 executes a synchronous retry control process that is a maintenance function when the current time reaches the synchronous retry control execution time shown in FIG. 5 (step S23). ). This synchronous retry control process executes the wireless synchronous control process again by autonomously resetting and restarting the device at the synchronous retry control execution time set in the internal ID-ROM. is there.

  The wireless side CPU 29, after executing a synchronization retry control process in step S23, restarts, and then proceeds to step S12 to execute the wireless synchronization control process again.

  In addition, the wireless synchronization retry control process in step S23 is not limited to the self-running mode service in step S17, but after the service operation is started in the wireless synchronization mode in step S21, the synchronization-destination wireless base station malfunctions or external radio waves. Even when a loss of synchronization occurs due to factors such as interference and the process shifts to the self-running mode service in step S17, the synchronous retry control process is started when the current time reaches the synchronous retry control execution time described above. is there.

  Next, the control CH signal scan process of step S14 in the wireless synchronization control process of FIG. 6 will be described. FIG. 8 is a flowchart showing a processing operation related to the control CH signal scanning process of the IP connection type radio base station 10.

  In FIG. 8, the radio side CPU 29 initializes the maximum reception level for the set control CH signal frequency (step S31), and sets the maximum number of reception times of the control CH signal to the control CH transmission cycle (N = 25 to 60) defined by the RCR standard. ) In FIG. 16 (b) to forcibly switch from the normal mode to the reception mode so that the control CH signal can be received (step S32A). ).

  As shown in FIG. 16C, the normal mode corresponds to a mode on the radio base station side that matches the transmission and reception timings of the reference station 1A, and the reception mode refers to FIG. 16B. As shown in FIG. 5, even when the radio wave transmission timing is reached, it corresponds to a mode on the radio base station side forcibly receiving radio waves. During the reception mode, the radio wave cannot be transmitted, so that the wave is stopped. In the process of this initial state (step S14), the slave station continues to be in the reception mode state until the radio wave transmitted by the reference station is received and synchronization is established.

  When the radio side CPU 29 switches to the reception mode in step S32A, the radio side CPU 29 starts the control CH signal reception operation within the N interval range (step S33).

  The radio side CPU 29 determines whether or not the call code of the received control CH signal matches the call code of its own station related to the radio synchronization condition shown in FIG. 4 (step S34). Note that the call code of the control CH signal is acquired by control information (hereinafter simply referred to as control CH information) included in the control CH signal periodically broadcast at N intervals.

  When it is determined that the call codes match, the radio side CPU 29 determines whether or not the reception level of the received control CH signal is equal to or higher than the threshold level defined for the reception level related to the radio synchronization condition shown in FIG. (Step S35). The reception level of the control CH signal is acquired by control CH information that is periodically broadcast at N intervals.

  If the radio side CPU 29 determines that the reception level is equal to or higher than the threshold level, the additional ID of the radio base station related to the received control CH signal is more than the additional ID of the own station related to the radio synchronization condition shown in FIG. It is determined whether the number is a young number (step S36). The additional ID of the radio base station related to the control CH signal is obtained from control CH information periodically broadcast at N intervals.

  When it is determined that the additional ID of the received control CH signal is a lower number than that of the own station, the radio side CPU 29 determines that the control CH signal satisfies all the radio synchronization conditions shown in FIG. The control CH signal is determined as the control CH signal of the synchronization destination candidate radio base station.

  Further, the radio side CPU 29 performs a correction process for matching the timings of the detected synchronization destination candidate radio base station and the own station in units of frames (step S37). In this correction process, the shift amount is sequentially corrected every time the control CH signal is received.

  The radio side CPU 29 determines whether or not the absolute slot position information has been received with the control CH information periodically notified at N intervals (step S38). The absolute slot position information is the transmission slot position of the control CH signal in the TDMA-TDD frame of the synchronization target candidate radio base station, and this absolute slot position information is all control CH information transmitted every N intervals. It is broadcast as radio channel information in a super frame (which is a multiplexed N frame shown in FIG. 7) which is a component unit.

  If the wireless side CPU 29 has received the absolute slot position information, the wireless side CPU 29 recognizes the transmission position of the control CH signal of the synchronization destination candidate radio base station in slot units, and adds the additional ID and reception level of the synchronization destination candidate radio base station. The transmission position of the control CH signal is stored in the wireless function memory unit 28 (step S39).

  Further, the wireless side CPU 29 determines that the control CH signal has been successfully received at this scan timing, and forcibly sets the number of receptions to avoid unnecessary reception operation of the control CH signal in the prescribed interval range. (Step S40), and the reception mode set in step S32A is switched to the normal mode (step S40A).

  When returning to the normal mode, the wireless side CPU 29 determines whether or not the number of receptions has reached the maximum number of receptions (step S41). If the number of receptions reaches the maximum number of receptions, the radio side CPU 29 shifts the timing to delay the timing by 10 bits in 240 bits per slot (step S42), and this control CH signal is assigned. It is determined whether or not the search for the timing of all 240 bits in the slot has been completed (step S43).

  Note that the process of shifting the timing by 10 bits in step S42 in the direction of delaying the timing is defined by the bit width that can be scanned by one process according to the hardware performance of the device, and the set transmission position of the control CH signal In step S32, the control CH signal is repeatedly scanned until the timing of all 240 bits of the slot to which the control CH signal is allocated at the 10-bit interval is completed. To do.

  If the search for all 240 bits is completed for the N intervals in step S43, the radio side CPU 29 recognizes the transmission position of the control CH signal in slot units and bit units by the timing shift of 10 bits in step S42. The exact sending position of this control CH signal is stored in step S39.

  Accordingly, if all 240 bits have been searched in step S43, the radio side CPU 29 determines that the transmission position of the control CH signal of the synchronization target candidate radio base station has been scanned over the entire range of N intervals. Then, the timing is advanced by 240 bits to the search start position (step S44), the original position is restored, and the control CH signal is successfully received and the synchronization destination candidate radio base station is detected by a series of control CH signal scan processes. It is determined whether or not (step S45).

  The radio side CPU 29 detects the synchronization destination candidate radio base station, and if the reception of the absolute slot position of the control CH signal is successful, the control CH reception processing data (call code, reception level, reception) (Timing deviation amount) is processed (step S46), and the process proceeds to the control CH positioning process of step S18 of FIG. 6 (step S47).

  On the other hand, if it is determined that the absolute slot position information is not received despite the wireless synchronization condition being satisfied in step S38, the wireless CPU 29 continues to monitor the reception of the absolute slot position information. The maximum number of times of reception is extended (step S48), and the counter of the number of times of reception is incremented by +1 (step S49) to return to the normal mode, as in the case where the wireless synchronization conditions in steps S34, S35 and S36 are not satisfied. The process proceeds to step S40A.

  On the other hand, if the number of receptions has not reached the maximum number of receptions in step S41, the radio side CPU 29 proceeds to step S32A to switch to the reception mode again.

  In addition, if the wireless side CPU 29 has not detected the synchronization destination candidate radio base station in step S45, the radio side CPU 29 determines whether or not the guard time (detection execution time) for Tx possessed by the control software has elapsed. (Step S50).

  If the guard time (detection execution time) for Tx has elapsed, the wireless side CPU 29 recognizes the synchronization position detection failure (step S51) and forcibly operates in the free-running mode service in step S17 of FIG. (Step S52).

  On the other hand, if the Tx guard time has not elapsed in step S50, the wireless CPU 29 determines whether or not the control CH mode is “3” (step S53). For the control CH mode, the setting when both the control CH signals assigned to the two frequencies of 12CH and 18CH are used is “3”, and the case where only the control CH signal of 12CH is used is “ The case where only 1 "and 18CH control CH signals are used is set as" 2 ".

  When it is determined that the control CH mode is “3”, the radio side CPU 29 switches the control CH signal to a frequency in which scanning is not performed (step S54), and controls the frequency in which scanning is not performed. In order to receive the CH signal, the process proceeds to step S32.

  On the other hand, if it is determined in step S53 that the control CH mode is not “3”, the radio side CPU 29 proceeds to step S32 in order to receive the same control CH signal again until Tx has elapsed.

  According to the control CH signal scan processing shown in FIG. 8, the accurate transmission position of the control CH signal related to the synchronization destination candidate radio base station that satisfies the radio synchronization condition within the interval range is determined not only in slot units but also in bit units. Can be detected.

  Next, the control CH positioning process of step S18 in the wireless synchronization control process of FIG. 6 will be described. FIG. 9 is a flowchart showing a processing operation related to the control CH positioning process of the IP connection type radio base station 10.

  In FIG. 9, the radio side CPU 29 initializes the retry counter (step S61), and then sets the control CH signal frequency of the synchronization destination radio base station (step S62).

  The radio side CPU 29 avoids the failure of the alignment process due to the shift of the transmission timing of the control CH signal of the synchronization destination radio base station due to the passage of time from the control CH signal scan process of FIG. 8 to the shift to the control CH alignment process. Accordingly, the own station timing is shifted to one slot ahead of the transmission position of the control CH signal of the synchronization destination radio base station (step S63), and the normal mode is switched to the reception mode (step S63A). During the reception mode, the wave is stopped.

  Further, the radio side CPU 29 executes the receiving operation of the control CH signal of the synchronization destination radio base station (step S64), switches the reception mode set in step S63A to the normal mode (step S64A), and this control CH signal. It is determined whether or not the reception has succeeded (step S65). Note that at the beginning of reception of the control CH signal, the own station timing is shifted one slot ahead of the synchronization destination in step S63, and therefore the control CH signal of the synchronization destination radio base station cannot be received.

  If the radio side CPU 29 has not successfully received the control CH signal at step S65, the radio side CPU 29 delays the reception timing by 10 bits so that the own station timing matches the transmission position of the control CH signal of the synchronization destination radio base station. (Step S66), and the retry counter is incremented by +1 for each shift (step S67).

  The radio side CPU 29 determines whether or not the retry counter has reached the number of times (25 times) exceeding the timing shift for one slot (240 bits), that is, whether or not the retry has been over (step S68).

  If the CPU 29 on the wireless side has retried over, the radio wave of the synchronization destination wireless base station cannot be received for some reason, and it is determined that the synchronization is impossible, and the device is forcibly reset and restarted. (Step S69), the process proceeds to step S63A in order to switch to the reception mode again in order to receive the control CH signal of the synchronization destination radio base station. At this time, since the device has been reset, the processing of the entire software is resumed from the wireless base station power ON in step S11 shown in FIG. If retry over is not performed in step S68, the process proceeds to step S63A to switch to the reception mode.

  If the CPU-side radio 29 succeeds in receiving the control CH signal in step S65, the radio-side CPU 29 determines that the transmission position of the control CH signal of the synchronization-destination radio base station and that of the own station match, By correcting the shift amount (step S70), the synchronization target radio base station and the own station are completely locked in a synchronized state.

  Further, the radio side CPU 29 initializes the retry counter, the measurement number counter, and the deviation amount accumulation counter (steps S71, 72, 73), and proceeds to the basic deviation amount measurement process shown in step S19 of FIG. 6 (step S74).

  According to the control CH positioning process shown in FIG. 9, the timing of the transmission position of the control CH signal of the local station is adjusted in bit units to the transmission position of the control CH signal of the synchronization target radio base station. The base station and the own station can be synchronized.

  Next, the basic deviation amount measurement process of step S19 in the wireless synchronization control process of FIG. 6 will be described. FIG. 10 is a flowchart showing processing operations related to the basic deviation amount measurement processing of the IP connection type radio base station 10.

  In radio synchronization, the time-acceptable deviation width in a TDMA-TDD frame is within 52.1 μS, but this tolerance inherently absorbs the transient response time for radio wave transmission and stop by the hardware of the radio equipment. Since it is necessary to consider about 40 μs as a hardware error, the allowable error range that can be assigned to this wireless synchronization software control is about 12 μs obtained by subtracting the hardware error 40 μs from 52.1 μs and converted into bits. Then it is 5 bits.

  The basic deviation amount measurement processing shown in FIG. 10 is to perform timing monitoring and correction processing of the synchronization target radio base station periodically after the start of actual operation in order to maintain the synchronization state within an allowable error range of a bit margin of 5 bits. The data of the basic deviation amount m is acquired.

  In FIG. 10, the radio side CPU 29 increments the measurement number counter initialized in step S72 of FIG. 9 by 1 (step S81), switches the normal mode to the reception mode (step S81A), and again performs the synchronization destination radio. The control channel signal reception operation of the base station is executed, and it is determined whether or not the synchronization target radio base station has successfully received the control CH signal (step S82). During the reception mode, the wave is stopped.

  If the radio side CPU 29 succeeds in receiving the control CH signal, the radio side CPU 29 switches the reception mode to the normal mode (step S82A), clears the retry counter (step S83), and sets the synchronization destination radio based on this reception information. The shift amount of the TDMA-TDD frame timing between the base station and the local station is corrected in bit units (step S84).

  Further, the wireless side CPU 29 adds the timing shift amount based on the received information to the shift amount accumulation counter (step S85), and determines whether 30 seconds have elapsed (step S86).

  Note that the series of processes does not require a lot of startup time at the start of actual operation, while operating the normal service function, minimizing the impact on the call quality on the service function, and stabilizing the wireless synchronization state This is repeatedly executed for the optimum 30 seconds for acquiring the data of the basic deviation amount necessary for continuing the operation.

  If 30 seconds have elapsed in step S86, the wireless side CPU 29 multiplies the accumulated value of the deviation amount accumulation counter by T / 30 (monitoring period T seconds shown in FIG. 7), thereby correcting the subsequent correction processing period. A basic deviation amount m corresponding to T seconds is calculated (step S87), and a measurement number counter and a deviation accumulation counter are initialized (step S88). The basic deviation amount m in step S87 is used as basic data for basic deviation amount prediction / correction processing in FIG.

  Thereafter, in order to monitor the synchronization timing of the TDMA-TDD frame with the synchronization target radio base station in parallel with the actual operation of the device, the radio CPU 29 controls the control CH signal of the synchronization target radio base station as shown in FIG. Is set to t1 seconds, which is the initial monitoring period after the start of actual operation (step S89), and the radio wave reception mode is switched from the reception mode of the control CH signal of the synchronization destination radio base station to the normal mode ( Step S90), the wireless synchronization control is completed. Thereafter, the process proceeds to the sorting start waiting process in step S20 shown in FIG. 6 (step S92).

  On the other hand, if the reception of the control CH signal is not successful in step S82, the wireless CPU 29 switches the reception mode set in step S81A to the normal mode (step S82B) and increments the retry counter by +1 ( Step S93), it is determined whether or not the retry counter has reached the maximum value (Step S94).

  If the retry counter has not reached the maximum value, the radio side CPU 29 proceeds to step S81 to execute the control CH signal reception operation. If the retry counter reaches the maximum value in step S94, the radio side CPU 29 determines that the radio reception of the synchronization target radio base station has failed, resets the device of the own station, and executes the restart. (Step S95).

  According to the basic deviation amount measurement processing shown in FIG. 10, after matching the transmission position of the control CH signal of the synchronization destination candidate radio base station and the own station, the time difference between the synchronization destination control CH signal and the synchronization destination control CH signal for each specified period. The deviation amount can be measured and held in the timing adjustment table as basic deviation amount data in bit units.

  Next, the sorting start waiting process of step S20 in the wireless synchronization control process of FIG. 6 will be described. FIG. 11 is a flowchart showing the processing operation related to the segregation start waiting process of the IP connection type radio base station 10.

  In the segregation start waiting process shown in FIG. 11, the start timing of segregation control for determining the transmission position of the control CH signal of the own station is shifted in time, and thereafter, the control CH signal of the other radio base station is controlled. In this process, the transmission position of the control CH signal of the own station is determined as an optimal transmission position so as not to overlap with the transmission position.

  The wireless CPU 29 shown in FIG. 11 recognizes the completion of the wireless synchronization control (step S101), and thereafter, the parameter for the start time for waiting for separation set in the address “106” of the built-in ID-ROM described in FIG. The number of lower significant bit digits (up to 8 bits) of the local station additional ID is stored (step S102), and is set to the lower significant bit number of the local station additional ID and the address “105” of the ID-ROM. By integrating the reference timer time, the start timer time of segregation control is calculated (step S103). For example, when the reference timer time is “30 seconds”, the number of lower significant bit digits is 4, the additional ID of the own station is “02”, the lower valid bit value is “2”. It is 60 seconds by calculating second × 2.

  The wireless CPU 29 determines whether or not the calculated start timer time is “0” (step S104). When it is determined that the start timer time is “0”, the radio side CPU 29 determines that there is no selection start waiting time, and immediately determines the transmission position of its own control CH signal within the interval range. The control operation is started (step S105), and the transmission position of the control CH signal of the own station is determined so as not to overlap with another IP-connected radio base station 10 within the interval range, and then shown in step S21 of FIG. Service operation in the wireless synchronization mode is started (step S106).

  On the other hand, if it is determined in step S104 that the start timer time is not “0”, the radio side CPU 29 activates the start timer time (step S107), and when the start timer times out (step S108), The process proceeds to step S105 in order to start the control operation for sorting the transmission positions of the control CH signal.

  According to the segregation start queuing process shown in FIG. 11, after establishing synchronization in the wireless section with the reference wireless base station, the number of lower significant bits of the additional ID of the own station and the reference timer time are integrated. The start timer time is calculated, and after starting the start timer time and the start timer time has elapsed, the processing operation of the segregation control for determining the transmission position of the control CH signal of the own station is executed. Situation where the start timing of the split control is shifted in time to perform the split control for determining the transmission position of the control CH signal simultaneously with other radio base stations, and the individual transmission positions are determined as overlapping positions Thus, smooth segregation control can be provided.

  Next, the state monitoring / correction control process in the wireless synchronization mode service process of step S21 in the wireless synchronization control process of FIG. 6 will be described. FIG. 12 is a flowchart showing processing operations related to the state monitoring / correction control processing of the IP connection type radio base station 10.

  The state monitoring / correction control process shown in FIG. 12 is for one cycle of the TDMA-TDD frame of the synchronization target wireless base station, as shown in FIG. 7, in order to maintain the wireless synchronization state in the synchronous mode service operation. The synchronization timing corresponding to the monitoring period (T seconds) is scanned every set scanning period t1 (or t2) seconds, and the frame timing of the synchronization destination radio base station obtained every scanning period t1 (or t2) And an updated value of the basic deviation amount m corresponding to one monitoring period (T seconds) is obtained based on the scanning result of the scanning period t1 (or t2). It can be processed. The updated value of the basic deviation amount m becomes basic data for the integrated value of the deviation amount counter in the deviation amount prediction / correction process of FIG.

  The wireless CPU 29 shown in FIG. 12 switches the normal mode to the reception mode to receive the control CH signal after incrementing the measurement number counter by +1 (step S112) during the synchronous mode service operation (step S111). Thus (step S112A), the receiving operation to the control CH signal of the synchronization destination radio base station is executed, and it is determined whether or not the control CH signal has been successfully received (step S113). During the reception mode, the wave is stopped.

  If the radio side CPU 29 succeeds in receiving the control CH signal, the radio side CPU 29 switches the reception mode set in step S112A to the normal mode (step S113A), and sets the control CH signal of the synchronization destination radio base station and the own station. The deviation amount from the control CH signal is accumulated in the continuous monitoring deviation amount accumulation counter (step S114).

  The radio side CPU 29 determines whether or not a bit shift of ± 3 bits or more has occurred between the control CH signal of the synchronization destination radio base station and the control CH signal of the local station (step S115). If it is determined that a bit shift of ± 3 bits or more has occurred, the wireless side CPU 29 corrects the bit shift amount (step S116). Note that the reason why the bit shift of less than ± 3 bits is allowed in step S115 is that the sequential shift correction is performed in the range of ± 1 bit by interruption for each slot in the basic shift amount prediction / correction processing of FIG. 14 described later. Because.

  When correcting the bit shift amount, the wireless side CPU 29 determines whether or not the number of measurements for one cycle of the monitoring period T (seconds) is equal to or greater than the specified number (T / t1) (step S117). When it is determined that the number of measurements is equal to or greater than the specified number (T / t1), the wireless CPU 29 determines whether or not the number of measurements is the specified number (T / t1) (step S118).

  When it is determined that the number of measurements is the specified number of times T / t1, the wireless side CPU 29 calculates the total data amount (1000 T / 5) corresponding to the monitoring cycle T seconds for one cycle shown in FIG. An updated value of the basic deviation amount m is calculated by dividing by the sum of the basic deviation amount m calculated in S87 and the accumulated value of the deviation amount accumulation counter measured this time (step S119).

  The radio side CPU 29 updates the basic deviation amount m held in the current timing adjustment table based on the calculation result of step S119.

  Further, after calculating the update value of the basic deviation amount m, the radio side CPU 29 sets the control CH signal reception interval of the synchronization destination radio base station to the first cycle, for example, at the time of power activation as shown in FIG. The setting is changed from the scan cycle t1 second to the scan cycle t2 seconds (= t1 × 10 seconds) after the second cycle, for example, during service operation, which becomes longer (step S120).

  There are two reasons for changing the scan period from t1 seconds to t2 seconds. First, even during an instantaneous time of 5 ms for scanning, since switching from the normal mode to the reception mode is performed only for synchronization monitoring, a communication error occurs in the wireless section during that time. This is to keep the error rate to a minimum and prevent the deterioration of the voice call quality of the normal service. Further, the second point is that the basic shift amount measurement process (see FIG. 10) and the first cycle process have already been successful in the monitoring after the second cycle, so that the wireless synchronization state can be reliably maintained. The point is that it can be determined that data of the basic deviation amount m has been acquired.

  When the setting is changed to the monitoring cycle t2 seconds in step S120, the radio side CPU 29 initializes the measurement number counter and the deviation monitoring cumulative amount counter for continuous monitoring (step S121), and then shifts to the monitoring operation in the next cycle and thereafter. (Step S122).

  On the other hand, if the reception of the control CH signal is not successful in step S113, the wireless CPU 29 switches the reception mode being set in step S112A to the normal mode (step S113B), and increments the retry counter by +1. (Step S123), it is determined whether or not the retry counter has retried over (Step S124).

  When it is determined that the retry counter has retried over, the radio side CPU 29 forcibly sets the reception interval (scan cycle) to t2 seconds that does not affect the call quality (step S125), and then synchronizes as radio synchronization failure. The self-running mode service is operated in a disconnected state (step S126).

  On the other hand, when the radio side CPU 29 shifts to the monitoring operation of the next cycle in step S122, it shifts to the processing operation of step S111. In this case, the specified number of times for the number of measurements in step S117 and step S118 is not T / t1, but T / t2. (T1 second applies only to the first cycle monitoring).

  According to the state monitoring / correction control process shown in FIG. 12, the synchronization timing corresponding to the monitoring period (T seconds) of one cycle of the TDMA-TDD frame of the synchronization target radio base station is set to the set scan period t1 (or t2) Scans every second, corrects the amount of bit deviation from the frame timing of the synchronization-destination radio base station obtained every scan period t1 (or t2), and displays the monitoring result of the scan period t1 (or t2). Based on this, since the update value of the basic deviation amount m corresponding to the monitoring cycle (T seconds) for one cycle is obtained, the wireless synchronization state in the synchronous mode service operation can be stably maintained.

  Next, the wireless synchronization retry control process of step S23 in the wireless synchronization control process of FIG. 6 will be described. FIG. 13 is a flowchart showing processing operations related to the wireless synchronization retry control processing of the IP connection type wireless base station 10.

  The wireless synchronization retry control process shown in FIG. 13 is a case where the synchronization state is lost due to failure or reset of the synchronization destination wireless base station, or due to radio wave interference by other wireless devices, and when synchronization is lost. When the current time becomes the retry control execution time, this is a process of executing a retry operation for wireless synchronization according to a predetermined condition.

  When the wireless CPU 29 shown in FIG. 13 executes an interrupt monitoring process at an arbitrary Y-second cycle (step S131), the operation mode setting set in the address “29” of the built-in ID-ROM shown in FIG. 5 is synchronized. It is determined whether or not the mode is selected (step S132).

  If it is determined that the operation mode setting is the synchronous mode, the wireless CPU 29 determines whether the synchronous retry control execution time set in the address “30” of the built-in ID-ROM shown in FIG. It is determined whether or not (step S132A).

  If it is determined that the synchronous retry control execution time is not other than 0 to 23, the wireless side CPU 29 determines whether or not the current time is the synchronous retry control execution time set in the address “30” of the ID-ROM. (Step S133).

  When it is determined that the current time is the synchronous retry control execution time, the radio side CPU 29 determines whether or not the own station currently holds the operation state in the synchronous mode (step S134).

  If it is determined that the own station does not currently maintain the operation state in the synchronous mode, the wireless side CPU 29 determines that the voice CH in use by performing the reset when it is in the free-running mode due to loss of synchronization. In order to prevent forcible disconnection in advance, it is determined whether or not all voice channels are empty (step S135).

  If it is determined that all voice channels are empty, the wireless side CPU 29 has already performed the retry operation on the same day in order to prevent a problem that the service operation is stopped unnecessarily by repeating the reset operation. It is determined whether or not a reset execution flag indicating ON is ON (step S136).

  When it is determined that the reset execution flag is not ON, the wireless side CPU 29 determines that the same retry operation is not performed on the same day, sets the reset execution flag to ON (step S137), and performs wireless synchronization retry operation. The reset operation is executed by (Step S138), and this processing operation is terminated.

  If it is determined in step S132 that the mode is not the synchronization mode, or if it is determined in step S132A that the synchronous retry control execution time is other than 0 to 23, or the radio side CPU 29 is performing the synchronous operation in step S134. If it is determined that there is, or if it is determined in step S135 that all voice CHs are not empty, this processing operation is terminated without executing the reset operation by the wireless synchronization retry operation.

  When determining that the reset execution flag is ON in step S136, the wireless side CPU 29 determines that the same wireless synchronization retry operation has been performed on the same day, and executes the reset operation by this wireless synchronization retry operation. This processing operation is finished without.

  If it is determined in step S133 that the current time is not the synchronous retry control execution time, the wireless CPU 29 sets the reset execution flag to OFF (step S139), and ends this processing operation.

  According to the wireless synchronization retry control process shown in FIG. 13, the current time becomes the retry control execution time during loss of synchronization, and if all the conditions of steps S132, 132A, 133, 134, 135, 136 are satisfied, By executing the resetting of the device and executing the processing operation of the wireless synchronization control again, it is possible to autonomously recover to the synchronization mode and guarantee the stable operation of the system.

  FIG. 14 is a flowchart showing processing operations related to the basic deviation amount prediction / correction processing of the synchronization timing of the IP connection type radio base station 10.

  The basic deviation amount prediction / correction process shown in FIG. 14 is always performed by an interrupt process using a subroutine program with built-in firmware, and the basic TDMA-TDD frame timing deviation between the own station and the synchronization target radio base station with respect to the next monitoring cycle is basically determined. Based on the deviation amount m, the value accumulated in the deviation amount accumulation counter is fed back to the frame correction register built in the hardware TDMA-TDD processing unit 26, and the timing deviation is within a range of ± 1 bit. This is a subroutine process for predictive correction.

  In FIG. 14, the radio side CPU 29 generates an interrupt process for each slot of the TDMA-TDD frame (step S141), and determines whether or not the value of the deviation accumulation counter is other than 0 (step S142).

  If it is determined that the value of the deviation amount accumulation counter is other than 0, the wireless side CPU 29 determines that correction control is necessary, increments the timing correction counter by +1 (step S143), and then performs this timing correction. It is determined whether or not the counter has reached the number of frames shifted by 1 bit (step S144).

  When determining that the timing correction counter has reached the number of frames shifted by 1 bit, the wireless CPU 29 determines whether or not the value of the shift amount accumulation counter is 0 or more (step S145).

  When it is determined that the value of the shift amount accumulation counter is 0 or more, the radio side CPU 29 determines that the shift is in the plus direction and sets 1 in the frame correction register built in the hardware TDMA-TDD processing unit 26. Addition is performed (step S146).

  When the radio side CPU 29 adds 1 to the frame correction register, the radio side CPU 29 corrects the bit width in the slot at the time when the timing shift occurs based on the predicted shift amount calculated for the frame width of the local station. By clearing the timing correction counter (step S147), this processing operation is terminated.

  On the other hand, if it is determined in step S145 that the value of the deviation amount accumulation counter is not greater than or equal to 0, the radio side CPU 29 determines that the deviation is in the minus direction and subtracts 1 from the frame correction register (step S148). Then, based on the predicted deviation amount calculated for the frame width of the own station, correction is performed in bit units in the slot at the time when timing deviation occurs, and after completion of this correction processing, the process proceeds to step S147 to clear the timing correction counter To do.

  According to the basic deviation amount prediction / correction process shown in FIG. 14, it is always performed by the interruption process, and the deviation of the TDMA-TDD frame timing between the local station and the synchronization destination radio base station with respect to the next monitoring period is set to the basic deviation amount m. Based on the value accumulated in the deviation accumulation counter, the result is fed back to the frame correction register built in the TDMA-TDD processing unit 26 of the hardware, and the timing deviation is predicted and corrected within a range of ± 1 bit. Can do.

  According to the first embodiment, when it is determined that the own station is in the synchronization mode, the control CH signal is transmitted from the selected radio base station serving as a reference for frame synchronization among the plurality of radio base stations other than the own station. The frame signal transmission timing of the local station is matched with the transmission position of the control CH signal in the frame signal, and the frame synchronization in the wireless section between the local station and the reference wireless base station is performed. For example, a general wireless base station 1 connected to the private branch exchange 4 through the ISDN line 3, an IP connection wireless base station 10 connected to the private branch exchange 4 connected through the LAN line 6, and a digital cordless base unit Synchronous control of segregation control that establishes frame synchronization in the wireless section and determines the transmission position of the control CH signal after synchronization is established even between two different types of wireless base stations such as 2 By performing the waiting time to absorb the time difference between start with, while ensuring an efficient effective utilization of radio waves, it is possible to prevent interference between the radio base station, it is possible to greatly improve the service quality.

  According to the first embodiment, as shown in the control CH signal scanning process of FIG. 8, when a frame signal including a control CH signal is received from a radio base station other than the own station, control information included in this frame signal is received. The call code, reception level and additional ID of the radio base station that sent this frame signal are detected, the call codes of the radio base station and the own station match, and the reception level between the radio base station and the own station is If it is determined that the wireless base station satisfies the reference condition for the wireless synchronization of the local station based on the comparison of the additional IDs of the wireless base station and the local station, the wireless base station is Since the reference radio base station is determined, each radio base station in the entire system can set the optimum radio base station as the reference radio base station.

  According to the first embodiment, as shown in the wireless synchronization retry control process of FIG. 13, even if the synchronization state in the wireless section between the local station and the reference wireless base station cannot be maintained, When the current time is the synchronization retry control execution time, since the wireless synchronization processing for reestablishing synchronization in the wireless section between the local station and the reference wireless base station is executed, the local station and the wireless base station It is possible to autonomously recover the synchronization state.

  According to the first embodiment, as shown in the control CH signal scanning process of FIG. 8, when it is determined that the local station is in the synchronous mode, the timer for measuring the detection execution time Tx is started and this detection is performed. If the synchronization in the radio section between the own station and the reference radio base station cannot be established within the execution time Tx, the radio signal of the frame signal is output at an arbitrary radio wave transmission timing of the own station. Since the operation in the self-propelled mode is started, the situation where the synchronization between the base radio base station and the own station in the radio section cannot be established and the service operation cannot be started reliably is ensured. It can be avoided.

  According to the first embodiment, the self-running mode for outputting the radio wave of the frame signal at an arbitrary radio wave transmission timing of the own station and the synchronization in the radio section between the own station and the reference radio base station are established. After that, the radio base station has an operation mode including a synchronization mode for outputting a radio wave of a frame signal, and the operation mode of each radio base station is set according to a predetermined operation from a maintenance terminal connected to the control device of the private branch exchange 4. Since the setting can be arbitrarily changed, even if the setting of the operation mode of the radio base station needs to be changed after the system operation, such a setting change can be sufficiently dealt with.

  According to the first embodiment, as shown in the segregation start waiting process in FIG. 11, after establishing synchronization in the radio section with the reference radio base station, the additional ID of the own station (maximum 8 The start timer time is calculated by integrating the number of lower significant bits) and the reference timer time. The start timer time is activated, and after the start timer time has elapsed, the transmission position of the control CH signal of the own station is determined. Since the processing operation of segregation control is executed, segregation control is performed in which a plurality of radio base stations simultaneously determine the transmission position of the control CH signal by shifting the start timing of segregation control in time. Such a situation can be avoided, and as a result, smooth segregation control can be provided.

  In the first embodiment, the embodiment has been described in which the reference station is the general wireless base station 1 and the wireless base station that is wirelessly synchronized with the reference station is the IP-connected wireless base station 10A. It goes without saying that the same effect can be obtained even if the wireless base station synchronized with the reference station is the digital cordless base unit 2.

  In the first embodiment, the operation mode, additional ID, etc. that are in operation are set for each radio base station (general type radio base station 1, IP connection type radio base station 10, and digital cordless base unit 2). Information, status information, and the like may be set, and the setting information and status information of the radio base station may be identified by various confirmation means as shown in FIG.

  For example, when the operation mode and additional ID during operation of each radio base station are collectively managed by the control device of the private branch exchange 4 and a maintenance command is input from the maintenance terminal connected to the serial port of this control device, the maintenance terminal , The operation mode of a specific radio base station, status information such as starting, self-running mode, synchronous mode, blocking, failure or power off, additional ID of the synchronization target radio base station, Control CH information or the like may be displayed on the screen. Note that various information such as setting information and status information of a specific radio base station may be displayed on the screen from a PC terminal connected to the LAN line in accordance with a designation operation.

  Further, the information notification unit 27 of the IP connection type radio base station 10 includes an LED lamp and an LCD display unit. For example, the operation content during operation of the radio base station with the display content of the LED lamp, for example, blue and synchronous operation Medium, green may be informed of self-running operation, and red may be informed of closure, and the LCD display unit may be informed of the additional ID of the synchronization target wireless base station, the operation mode of the own station, and the like.

  Further, in the first embodiment, as shown in FIG. 16 (b), the control CH signal of the synchronization destination radio base station (reference station) 1A is forced from the normal mode to receive on the first slave station 10A side. The reception mode is switched to the reception mode and the control CH signal reception operation of the synchronization target radio base station is executed. However, the reception mode is stopped.

  Therefore, a mobile communication system 100A that can improve call quality by avoiding such a wave stop state will be described as a second embodiment.

(Embodiment 2)
FIG. 17 is an explanatory diagram briefly showing the system configuration of a mobile communication system 100A according to the second embodiment. Note that the same components as those in the mobile communication system 100 according to the first embodiment are denoted by the same reference numerals, and the description of the overlapping configuration and operation is omitted.

  A mobile communication system 100A shown in FIG. 17 has a single-layer system configuration in which a plurality of first slave stations 10A are wirelessly connected to a reference station 1A.

  When the first slave station 10A switches from the normal mode to the reception mode when the power is turned on and receives the control CH signal of the reference station 1A, as shown in FIG. 18, the first slave station 10A receives the control station 1A radio wave transmission timing. The radio wave reception timing is matched, the radio wave reception timing of the first slave station 10A is matched with the radio wave reception timing of the reference station 1A, and then the mode is switched to the normal mode.

  In addition, even if the first slave station 10A receives the control CH signal from the reference station 1A during service operation, the control from the reference station 1A remains in the normal mode without switching the normal mode to the reception mode. The CH signal is received. During service operation, the normal mode is maintained without switching to the reception mode, so that a wave stop state does not occur.

  In this single-layer mobile communication system 100A, the radio side CPU 29 of the first slave station 10A performs radio synchronization control processing shown in FIG. 6, control CH signal scan processing shown in FIG. 8, and control CH alignment processing shown in FIG. , Basic deviation amount measurement processing shown in FIG. 10, segregation start waiting processing shown in FIG. 11, state monitoring correction control processing shown in FIG. 12, wireless synchronization retry control processing shown in FIG. 13, basic deviation amount prediction / Correction processing is executed.

  However, since the radio side CPU 29 of the first slave station 10A receives the control CH signal from the reference station 1A in the normal mode during service operation, the steps S32A and S40A of FIG. 8 and FIG. It is possible to eliminate the processing operation for setting the switching between the normal mode and the reception mode in step S63A and step S64A, step S81A in FIG. 10, step S82A and step S82B, step S112A in FIG. 12, step S113A and step S113B. is there.

  According to the second embodiment, the first slave station 10A receives the frame signal including the control CH signal from the reference station 1A, and the first slave station 10A receives the control CH signal transmission position in the frame signal. The reception timing is matched, the transmission timing of the first slave station 10A is matched with the reception timing of the reference station 1A, and frame synchronization in the wireless section between the first slave station 10A and the reference station 1A is established. Therefore, for example, the general type radio base station 1 connected to the private branch exchange 4 through the ISDN line 3, the IP connection type radio base station 10 connected to the private branch exchange 4 connected through the LAN line 6, and the digital cordless base unit 2 are different types. By establishing frame synchronization in the wireless section even between wireless base stations, and performing segregation control to determine the transmission position of the control CH signal after synchronization is established at the waiting timing that absorbs the time difference of activation by synchronization control In addition to ensuring efficient and efficient use of radio waves, radio wave interference between radio base stations can be prevented, and service quality can be greatly improved.

  Furthermore, according to the second embodiment, even if the first slave station 10A receives the control CH signal from the reference station 1A during service operation, the normal mode is not switched to the reception mode. Since the control CH signal from the reference station 1A is received as it is, there is no instantaneous interruption of the line in the stop state when receiving the control CH signal from the reference station 1A. As a result, the call quality is greatly improved. Can be planned.

  In the second embodiment, the single-layer mobile communication system 100A has been described. However, various modes are conceivable as the single-layer mobile communication system.

  Then, next, the mobile communication system of various aspects of a single layer type is demonstrated sequentially.

(Embodiment 3)
FIG. 19 is an explanatory diagram showing a system configuration of a mobile communication system according to the third embodiment. The same components as those in the mobile communication system 100A according to the second embodiment are denoted by the same reference numerals, and the description of the overlapping configuration and operation is omitted.

  A mobile communication system 100B shown in FIG. 19 is a public base station synchronous mobile communication system in which the reference station 1A is a public base station and the first slave station 10A is an IP connection type radio base station 10. The first slave station 10A receives the frame signal including the control CH signal from the public base station serving as the reference station 1A, and matches the reception timing of the first slave station 10A with the transmission position of the control CH signal in the frame signal. The transmission timing of the first slave station 10A is matched with the reception timing of the public base station, and the frame synchronization in the radio section between the first slave station 10A and the reference station 1A is established. Note that the first slave station 10A uses the public base station having the highest reception level among the plurality of public base stations as the reference station 1A of the own station.

  Even if the radio side CPU 29 of the first slave station 10A receives the control CH signal from the public base station that becomes the reference station 1A during service operation, the normal mode remains in the normal mode without switching the normal mode to the reception mode. The control CH signal is received from the reference station 1A.

  Further, if the first slave station 10A becomes unable to synchronize with the reference station 1A due to maintenance work of the reference station 1A, for example, the first slave station 10A shifts to a self-running state, and a plurality of public By searching for a public base station having the highest reception level among the base stations and setting the public base station having the highest reception level as the reference station 1A of the own station, frame synchronization in the wireless section between the own station and the reference station 1A is performed. Is to establish.

  According to the third embodiment, the first slave station 10A receives the frame signal including the control CH signal from the public base station serving as the reference station 1A, and at the transmission position of the control CH signal in the frame signal, The reception timing of the first slave station 10A is matched, the transmission timing of the first slave station 10A is matched with the reception timing of the public base station, and frame synchronization in the radio section between the first slave station 10A and the public base station is established. ing. Therefore, for example, even between the public base station and the IP connection type wireless base station 10, frame synchronization is established in the wireless section, and the segregation control for determining the transmission position of the control CH signal after the synchronization is established is activated by the synchronization control. By carrying out at the waiting timing that absorbs the time difference, it is possible to ensure efficient and efficient use of radio waves, to prevent radio interference between radio base stations, and to greatly improve service quality.

  Further, according to the third embodiment, even when the control signal is received from the public base station serving as the reference station 1A during service operation at the first slave station 10A, the normal mode is switched to the reception mode. Without receiving the control CH signal from the reference station 1A in the normal mode without any instantaneous interruption of the line in the wave-stopping state when receiving the control CH signal from the reference station 1A. The quality can be greatly improved.

  Further, according to the third embodiment, for example, even if the synchronization with the reference station 1A cannot be taken due to maintenance work or the like of the reference station 1A, the mobile station shifts to a self-running state, and when this self-running or scheduled reset comes, Since the public base station with the highest reception level is searched from among the plurality of public base stations and the public base station with the highest reception level is designated as the reference station 1A of the own station, Even if synchronization with the reference station 1A is lost, frame synchronization can be automatically established in the radio section with the other reference station 1A.

(Embodiment 4)
FIG. 20 is an explanatory diagram showing a system configuration of a mobile communication system according to the fourth embodiment. The same components as those in the mobile communication system 100A according to the second embodiment are denoted by the same reference numerals, and the description of the overlapping configuration and operation is omitted.

  A mobile communication system 100C shown in FIG. 20 includes a reference station 1A and a plurality of sub-reference stations 1B as a plurality of general wireless base stations 1 that are wired to the private branch exchange 4, and a first slave station 10A as a plurality of IP connection wireless base stations. The station 10, the reference station 1A, and the plurality of sub-reference stations 1B are direct synchronization type mobile communication systems synchronized with the ISDN network 4A connected to the private branch exchange 4 by wire.

  Further, the first slave station 10A receives and synchronizes the frame signal including the control CH signal from either the reference station 1A synchronized with the ISDN network 4A or the plurality of sub-reference stations 1B.

  The first slave station 10A matches the reception timing of the first slave station 10A with the transmission position of the control CH signal in the frame signal, matches the transmission timing of the first slave station 10A with the reception timing of the reference station 1A, Frame synchronization is established in a wireless section between one slave station 10A, the reference station 1A, and a plurality of sub-reference stations 1B.

  Even if the radio side CPU 29 of the first slave station 10A receives a control CH signal from either the reference station 1A or the plurality of sub-reference stations 1B during service operation, the normal mode is not switched to the reception mode. The control CH signal from the reference station 1A is received in the normal mode.

  The first slave station 10A does not designate the other first slave station 10A as its own reference station 1A, and the general radio base station 1 synchronized with the ISDN network 4A as its own reference station 1A or sub-reference station 1B. Assume that different call codes are assigned to the first slave station 10A, the reference station 1A, and the sub-reference station 1B so that they can be specified.

  The first slave station 10A searches for a radio base station having a call code of the reference station 1A and the sub-reference station 1B among the plurality of radio base stations and having the highest reception level, and uses the radio base station as its own station. The reference station 1A or the sub-reference station 1B is used.

  Further, the first slave station 10A shifts to a self-running state when the synchronization with the reference station 1A is lost due to, for example, a failure of the reference station 1A, and the plurality of radio base stations Among the stations, the base station 1A or the sub base station 1B having a call code and having the highest reception level is searched for, and the base station is set as the base station of the base station. This establishes frame synchronization in the wireless section. In this case, the calling codes of the reference station 1A and the sub reference station 1B may be the same as long as they are different from those of the slave station.

  According to the fourth embodiment, the first slave station 10A receives the frame signal including the control CH signal from the reference station 1A or the sub-reference station 1B synchronized with the ISDN network 4A through the private branch exchange 4, and the frame signal The reception timing of the first slave station 10A is adjusted to the transmission position of the control CH signal, the reception timing of the reference station 1A is adjusted to the transmission timing of the first slave station 10A, and the wireless communication between the first slave station 10A and the reference station 1A is performed. Since the frame synchronization is established, for example, the general wireless base station 1 connected to the ISDN network 4A through the private branch exchange 4, the IP connection type wireless base station 10 connected to the private branch exchange 4 connected through the LAN line 6, and the digital cordless Establish frame synchronization in the wireless section even between different types of wireless base stations such as the base unit 2 By implementing the segregation control for determining the transmission position of the control CH signal after establishment of the period at the waiting timing that absorbs the time difference of activation by the synchronous control, the radio base stations can be efficiently and efficiently used. Radio wave interference can be prevented, and service quality can be greatly improved.

  Further, according to the fourth embodiment, even if the first slave station 10A receives the control CH signal from the reference station 1A during service operation, the normal mode is not switched to the reception mode. Since the control CH signal from the reference station 1A is received in the mode, there is no instantaneous interruption of the line in the stop state when receiving the control CH signal from the reference station 1A, and as a result, the call quality is greatly improved. Can be achieved.

  Furthermore, according to the fourth embodiment, even if the first slave station 10A becomes unable to synchronize with the reference station 1A due to, for example, a failure of the reference station 1A, When a scheduled reset arrives, a radio base station having a call code of the reference station 1A and having the highest reception level is searched for from among a plurality of radio base stations, and the searched radio base station is designated as the reference station 1A of the own station. As described above, even if synchronization with the reference station 1A of the local station cannot be established due to a failure or the like, frame synchronization in the wireless section with another reference station 1A can be automatically established.

(Embodiment 5)
FIG. 21 is an explanatory diagram showing a system configuration of a mobile communication system according to the fifth embodiment. The same components as those in the mobile communication system 100A according to the second embodiment are denoted by the same reference numerals, and the description of the overlapping configuration and operation is omitted.

  In the mobile communication system 100D shown in FIG. 21, the reference station 1A is a single general radio base station 1 connected to the private branch exchange 4 by wire, and the sub reference station 10C, the first slave station 10A, and the second slave station 10B An IP connection type wireless base station 10 is used, and the reference station 1A is an indirect synchronization type mobile communication system synchronized with an ISDN network 4A connected to the private branch exchange 4 by wire.

  The sub-reference station 10C and the first slave station 10A receive and synchronize the frame signal including the control CH signal from the reference station 1A synchronized with the ISDN network 4A, but the sub-reference station 10C is the first embodiment. Similar to the slave station related to the form, the transmission timing of the sub reference station 10C is matched with the transmission position of the control CH signal in this frame signal, and the reception timing of the sub reference station 10C is matched with the reception timing of the reference station 1A. Of course, when a control CH signal is received from the reference station 1A during service operation, synchronization correction is performed while switching the normal mode to the reception mode.

  In the case of the first slave station 10A, the reception timing of the first slave station 10A is matched with the transmission position of the control CH signal in the frame signal, and the transmission timing of the first slave station 10A is set to the reception timing of the reference station 1A. In addition, frame synchronization in the wireless section between the first slave station 10A and the reference station 1A is established.

  Also, the second slave station 10B in the mobile communication system 100D receives a frame signal including a control CH signal from the sub-reference station 10C that is frame-synchronized with the reference station 1A, and at the transmission position of the control CH signal in this frame signal, 2) The reception timing of the slave station 10B is matched, the transmission timing of the second slave station 10B is matched with the reception timing of the sub-reference station 10C, and frame synchronization in the radio section between the sub-reference station 10C and the second slave station 10B is established. It is a thing.

  Further, even if the radio side CPU 29 of the first slave station 10A and the second slave station 10B receives the control CH signal from the reference station 1A or the sub reference station 10C during service operation, the normal mode is switched to the reception mode. Instead, the control CH signal is received from the reference station 1A or the sub-reference station 10C in the normal mode.

  The first slave station 10A and the second slave station 10B can designate the general wireless base station 1 synchronized with the ISDN network 4A as the reference station of the own station without designating the other slave stations as the reference stations of the own station. Assume that different call codes are assigned to the first slave station 10A and the second slave station 10B and the reference station 1A and the sub-reference station 10C.

  The first slave station 10A and the second slave station 10B search for a radio base station having a call code of the reference station 1A or the sub-reference station 10C and having the highest reception level among the plurality of radio base stations. The base station is set as a reference station of the own station. In this case, the calling codes of the reference station 1A and the sub reference station 10C may be the same as long as they are different from those of the slave station.

  According to the fifth embodiment, the first slave station 10A receives the frame signal including the control CH signal from the reference station 1A synchronized with the ISDN network 4A through the private branch exchange 4, and the control CH signal in this frame signal is transmitted. The reception timing of the first slave station 10A is matched with the transmission position, the reception timing of the reference station 1A is matched with the transmission timing of the first slave station 10A, and frame synchronization in the radio section between the first slave station 10A and the reference station 1A is established. At the same time, the second slave station 10B receives the frame signal including the control CH signal from the sub reference station 10C synchronized with the reference station 1A, and the second slave station 10B receives the control CH signal in the transmission position of the frame signal. Match the timing and match the transmission timing of the second slave station 10B with the reception timing of the sub-reference station 10C. Sub reference station 10C and is configured to establish frame synchronization in the radio section with the second slave station 10B.

  Accordingly, different types of radio base stations such as the general type radio base station 1 connected to the private branch exchange 4, the IP connection type radio base station 10 connected to the private branch exchange 4 connected via the LAN line 6 and the digital cordless base station 2 are connected. Even so, by establishing frame synchronization in the wireless section and performing segregation control that determines the transmission position of the control CH signal after synchronization is established at the waiting timing that absorbs the time difference of activation by synchronization control, Effective use can be ensured, radio wave interference between radio base stations can be prevented, and service quality can be greatly improved.

  According to the fifth embodiment, even if the control CH signal is received from the reference station 1A or the sub-reference station 10C during service operation at the first slave station 10A and the second slave station 10B, the normal mode is changed to the reception mode. Since the control CH signal is received from the reference station 1A or the sub-reference station 10C in the normal mode without switching to the normal mode, there is no instantaneous interruption of the line in the wave stop state when receiving the control CH signal. As a result, the call quality can be greatly improved.

(Embodiment 6)
FIG. 22 is an explanatory diagram showing a system configuration of a mobile communication system according to the sixth embodiment. The same components as those in the mobile communication system 100A according to the second embodiment are denoted by the same reference numerals, and the description of the overlapping configuration and operation is omitted.

  A mobile communication system 100E shown in FIG. 22 is a public base station indirect synchronization mobile communication system in which the reference station 1A is a public base station, and the sub-reference station 10C and the second slave station 10B are IP connection type radio base stations 10.

  The sub-reference station 10C receives the frame signal including the control CH signal from the public base station serving as the reference station 1A, matches the reception timing of the sub-reference station 10C with the transmission position of the control CH signal in the frame signal, and receives the reference station 1A. The transmission timing of the sub-reference station 10C is matched with the timing to establish frame synchronization in the radio section between the sub-reference station 10C and the public base station.

  The second slave station 10B receives a frame signal including a control CH signal from the sub-reference station 10C synchronized with the reference station 1A, and the reception timing of the second slave station 10B at the transmission position of the control CH signal in the frame signal. , The transmission timing of the second slave station 10B is matched with the reception timing of the sub-reference station 10C, and frame synchronization in the radio section between the sub-reference station 10C and the second slave station 10B is established.

  Even if the radio side CPU 29 of the sub reference station 10C receives the control CH signal from the public base station that becomes the reference station 1A during service operation, the normal mode remains in the normal mode without switching the normal mode to the reception mode. The control CH signal from 1A is received.

  The sub-reference station 10C searches for a public base station having a call code of the reference station 1A among the plurality of radio base stations and having the highest reception level, and uses this public base station as its own reference station 1A. is there.

  Further, the sub-reference station 10C shifts to a self-running state when the synchronization with the reference station 1A is lost due to maintenance work or failure of the reference station 1A, for example. Among the base stations, the public base station having the call code of the reference station 1A and having the highest reception level is searched for, and the public base station is set as the reference station 1A of the own station, so that the wireless communication between the own station and the reference station 1A This establishes frame synchronization in the section.

  Further, even if the radio side CPU 29 of the second slave station 10B receives the control CH signal from the sub reference station 10C during service operation, the radio mode CPU 29 does not switch the normal mode to the reception mode and does not change the normal mode. The control CH signal is received from the reference station 10C.

  The second slave station 10B does not designate the other second slave station 10B as its own synchronization destination radio base station, and can designate the sub reference station 10C as its own synchronization destination radio base station. Assume that different call codes are assigned to 10C and the second slave station 10B.

  The second slave station 10B searches for a radio base station having a call code of the sub-reference station 10C among the plurality of radio base stations and having the highest reception level, and uses the sub-reference station 10C as a synchronization destination radio of its own station. The base station.

  In addition, the second slave station 10B shifts to a self-running state when, for example, the sub-reference station 10C is out of synchronization due to maintenance work or failure of the sub-base station 10C, and during this self-run or when a scheduled reset arrives, By searching for a radio base station having a call code of the sub-reference station 10C among the plurality of radio base stations and having the highest reception level, and making this sub-reference station 10C a synchronization-destination radio base station of the own station, This establishes frame synchronization in the radio section between the own station and the sub-reference station 10C.

  According to the sixth embodiment, the sub-reference station 10C receives a frame signal including the control CH signal from the public base station serving as the reference station 1A, and the sub-reference station 10C is located at the transmission position of the control CH signal in this frame signal. The base station is synchronized with the transmission timing of the sub-reference station 10C, the reception timing of the public base station is matched with the transmission timing of the sub-base station 10C, and the frame synchronization in the radio section between the sub-base station 10C and the public base station is established. The frame signal including the control CH signal from 10C is received by the second slave station 10B, and the reception timing of the second slave station 10B is adjusted to the transmission position of the control CH signal in the frame signal, and the second slave station 10B The transmission timing is matched with the reception timing of the sub reference station 10C, and the sub reference station 10C and the second slave station 10B It was to establish the frame synchronization of a line segment.

  Accordingly, different types of radio base stations such as the general type radio base station 1 connected to the private branch exchange 4, the IP connection type radio base station 10 connected to the private branch exchange 4 connected via the LAN line 6 and the digital cordless base station 2 are connected. Even so, by establishing frame synchronization in the wireless section and performing segregation control that determines the transmission position of the control CH signal after synchronization is established at the waiting timing that absorbs the time difference of activation by synchronization control, Effective use can be ensured, radio wave interference between radio base stations can be prevented, and service quality can be greatly improved.

  According to the sixth embodiment, even if the control channel signal is received from the public base station during service operation at the sub-reference station 10C, the normal mode is maintained without switching the normal mode to the reception mode. In addition to receiving the control CH signal from the public base station, the normal mode is switched to the reception mode even if the second slave station 10B receives the control CH signal from the sub-reference station 10C during service operation. Since the control CH signal is received from the sub-reference station 10C in the normal mode, there is no instantaneous interruption of the line when the control CH signal is received, and as a result, the call quality is greatly improved. Can be achieved.

  Further, according to the sixth embodiment, for example, even if the sub-reference station 10C becomes unable to synchronize with the reference station 1A due to maintenance work or the like of the reference station 1A, it shifts to the self-running state, and this self-running or fixed time When a reset arrives, a public base station having the highest reception level is searched from among a plurality of public base stations, and the public base station having the highest reception level is designated as the reference station 1A of the own station. Thus, even if synchronization with the reference station 1A of the local station cannot be established, it is possible to automatically establish frame synchronization in the radio section with the other reference station 1A.

(Embodiment 7)
A mobile communication system according to the seventh embodiment will be described with reference to FIG. The same components as those in the mobile communication system 100C according to the fourth embodiment are denoted by the same reference numerals, and the description of the overlapping configuration and operation is omitted.

  A mobile communication system 100C shown in FIG. 20 includes a reference station 1A and a plurality of sub-reference stations 1B as a plurality of general wireless base stations 1 that are wired to the private branch exchange 4, and a first slave station 10A as a plurality of IP connection wireless base stations. The station 10, the reference station 1A, and the plurality of sub-reference stations 1B are direct synchronization type mobile communication systems synchronized with the ISDN network 4A connected to the private branch exchange 4 by wire.

  Further, the first slave station 10A receives and synchronizes the frame signal including the control CH signal from either the reference station 1A synchronized with the ISDN network 4A or the plurality of sub-reference stations 1B.

  The first slave station 10A matches the reception timing of the first slave station 10A with the transmission position of the control CH signal in the frame signal, matches the transmission timing of the first slave station 10A with the reception timing of the reference station 1A, and Frame synchronization in the radio section between the slave station 10A, the reference station 1A, and the plurality of sub-reference stations 1B is established.

  Even if the radio side CPU 29 of the first slave station 10A receives a control CH signal from either the reference station 1A or the plurality of sub-reference stations 1B during service operation, the normal mode is not switched to the reception mode. The control CH signal from the reference station 1A is received in the normal mode.

  However, in the fourth embodiment, different call codes are assigned to the first slave station 10A, the reference station 1A, and the sub-reference station 1B, and the first slave station 10A includes a plurality of radio base stations, The base station 1A and the sub base station 1B having the call codes and having the highest reception level are searched for, and this base station is set as the base station 1A or sub base station 1B of its own station. In this embodiment, the first slave station 10A searches for a specific reference station based on the calling code and its own additional ID, and synchronizes with the reference station, regardless of the strength of the reception level of the radio wave transmitted from the reference station. It is something to take.

  Hereinafter, the operation will be described. First, the first slave station 10A stores the calling code and the own station additional ID of the reference station that it should synchronize with, and does not designate the other first slave station 10A as the reference station of its own station. The first slave station 10A, the reference station 1A, and the sub-reference station 1B are assigned different self-station additional IDs so that the general wireless base station 1 synchronized with the network 4A can be designated as the reference station 1A or sub-reference station 1B of the own station. Yes. In this case, the local station additional IDs of the reference station 1A and the sub-reference station 1B are different from those of the slave station, and the calling codes of the reference station 1A and the plurality of sub-reference stations 1B are different from each other.

  The first slave station 10A uses, as a reference station of its own station, a radio base station having a call code and a base station additional ID of the reference station to be synchronized among the plurality of wireless base stations.

  Here, not only the local station additional ID but also the call code match determination is performed even if the local station additional ID does not overlap in the same system group, there are other systems in the adjacent area. Since there is a possibility of overlapping with the assigned local station additional ID, a different calling code is also checked for each system.

  By doing so, it is possible to prevent erroneous connection such that a radio base station of another system is used as a reference station.

  Further, the first slave station 10A shifts to a self-running state when synchronization with the reference station becomes impossible due to, for example, a failure of the reference station.

  According to the seventh embodiment, similarly to the fourth embodiment, the frame signal including the control CH signal is transmitted from the reference station 1A or the sub-reference station 1B synchronized with the ISDN network 4A through the private branch exchange 4 to the first slave station 10A. The reception timing of the first slave station 10A is matched with the transmission position of the control CH signal in this frame signal, the reception timing of the reference station 1A is matched with the transmission timing of the first slave station 10A, and the first slave station Since the frame synchronization in the wireless section between 10A and the reference station 1A is established, for example, the general wireless base station 1 connected to the ISDN network 4A through the private branch exchange 4 and the private branch exchange 4 connected through the LAN line 6 are connected. Even if different types of radio base stations such as the IP connection type radio base station 10 and the digital cordless base unit 2 are used, In order to ensure efficient and efficient use of radio waves, frame segregation control is established in order to determine the transmission position of the control CH signal after synchronization is established at the waiting timing that absorbs the time difference of activation due to synchronization control. In addition, radio wave interference between radio base stations can be prevented, and service quality can be greatly improved.

  Even if the first slave station 10A receives a control CH signal from the reference station 1A during service operation, the control CH from the reference station 1A remains in the normal mode without switching the normal mode to the reception mode. Since the signal is received, there is no instantaneous interruption of the line in the wave stop state when receiving the control CH signal from the reference station 1A, and as a result, the call quality can be greatly improved.

  Furthermore, according to the seventh embodiment, the first slave station 10A is synchronized with the reference station of the specific call code. In other words, the master slave of the reference station 1A, the sub reference station 1B, and the first slave station 10A Since the system is designed to clarify the relationship, it is understood which reference station 1A or sub-reference station 1B is operating in synchronization with the first slave station 10A.

  For example, if the first slave station 10A becomes unable to synchronize with the reference station 1A due to a failure of the reference station 1A or the like, if the first slave station 10A is configured to notify the maintenance person that the first slave station 10A has entered a free-running state, It becomes easy to identify the failed reference station 1A, and the maintainability of the system can be improved.

  Although the seventh embodiment has been described based on the fourth embodiment shown in FIG. 20, when the slave station or sub-reference station is synchronized with a reference station having a specific calling code in the radio, the present invention When applied to the other embodiments described in the above, it becomes easy to identify the failed reference station 1A as described above, and the maintainability of the system can be improved.

  The mobile communication system of the present invention includes different types of wireless bases such as a general wireless base station connected to a private branch exchange via an ISDN line, an IP connection wireless base station connected to a private branch exchange connected via a LAN line, and a digital cordless base unit. Even between stations, synchronization is established in the wireless section, and by performing segregation control for determining the transmission position of the control CH signal after the synchronization is established, the radio base By preventing radio interference between stations, the service quality can be greatly improved, and there is no instantaneous interruption of the line when the control CH signal is received. As a result, the call quality is greatly improved. This is useful for a TDMA type mobile communication system and the like.

1 is a block diagram showing a schematic configuration inside a TDMA type mobile communication system according to a first embodiment of the present invention. FIG. 1 is a block diagram showing a schematic configuration inside an IP connection type base station related to a TDMA type mobile communication system showing a first embodiment; FIG. 1 is an explanatory diagram simply showing a system configuration (multilayer type) of a TDMA type mobile communication system according to a first embodiment; FIG. It is explanatory drawing which shows the radio | wireless synchronization conditions of the radio base station in 1st Embodiment. It is explanatory drawing which shows the setting information of the wireless base station in 1st Embodiment. It is a flowchart which shows the processing operation in connection with the radio | wireless synchronous control process of the IP connection type | mold radio base station in 1st Embodiment. It is explanatory drawing which shows directly the relationship of each monitoring period in the control CH transmission period concerning 1st Embodiment. It is a flowchart which shows the processing operation in connection with the control CH signal scanning process of the IP connection type | mold radio base station in 1st Embodiment. It is a flowchart which shows the processing operation regarding the control CH positioning process of the IP connection type | mold radio base station in 1st Embodiment. It is a flowchart which shows the processing operation in connection with the basic deviation amount measurement process of the IP connection type radio base station in the first embodiment. It is a flowchart which shows the processing operation in connection with the segregation start waiting process of the IP connection type | mold radio base station in 1st Embodiment. It is a flowchart which shows the processing operation regarding the state monitoring and the correction | amendment process of the IP connection type | mold radio base station in 1st Embodiment. It is a flowchart which shows the processing operation in connection with the synchronous retry control process of the IP connection type | mold radio base station in 1st Embodiment. It is a flowchart which shows the processing operation regarding the basic deviation amount prediction / correction process of the IP connection type radio base station in the first embodiment. It is explanatory drawing which shows the example for alerting | reporting the status information etc. of the wireless base station in connection with 1st Embodiment. It is explanatory drawing which shows the relationship of the electromagnetic wave transmission timing between the reference | standard station and slave station (IP connection type | mold radio base station) in 1st Embodiment. It is explanatory drawing which shows simply the system configuration | structure (single layer type) of the mobile communication system which shows 2nd Embodiment. It is explanatory drawing which shows the relationship of the electromagnetic wave transmission timing between the reference | standard station and slave station (IP connection type | mold radio base station) in 2nd Embodiment. It is explanatory drawing which shows simply the system configuration | structure (public base station synchronous type) of the mobile communication system which shows 3rd Embodiment. It is explanatory drawing which shows simply the system configuration | structure (direct synchronous type) of the mobile communication system which shows 4th Embodiment. It is explanatory drawing which shows simply the system configuration | structure (indirect synchronous type) of the mobile communication system which shows 5th Embodiment. It is explanatory drawing which shows simply the system configuration | structure (public base station indirect synchronization type) of the mobile communication system which shows 6th Embodiment. 1 is a block diagram showing a schematic configuration inside a general TDMA type mobile communication system. FIG. It is explanatory drawing which shows the concept of the TDMA-TDD frame used in the radio | wireless area of the mobile communication system of a general TDMA system. It is explanatory drawing which shows simply the control CH transmission period in the general TDMA type mobile communication system.

Explanation of symbols

1 General radio base station (radio base station)
2 Digital cordless master unit (wireless base station)
4 Private branch exchange 5A, 5B Slave unit (wireless slave unit)
10 IP connection type wireless base station (wireless base station)
100A, 100B, 100C, 100D, 100E Mobile communication system (mobile communication system)

Claims (5)

A mobile communication system having a plurality of radio base stations of different system types and a wireless slave unit that is wirelessly connected to the plurality of radio base stations,
The radio base station is
According to a preset synchronization mode, a frame signal including a control CH signal is received from a radio base station serving as a reference for frame synchronization selected from among the plurality of radio base stations other than the own station, A mobile communication system, characterized in that a reception timing of the own station is matched with a transmission position of a control CH signal, and frame synchronization is established in a radio section between the own station and the reference radio base station. The reference radio base station is a public base station synchronous mobile communication system corresponding to a public base station synchronized with a public network,
The radio base station is
In accordance with a preset synchronization mode, a frame signal including a control CH signal is received from the reference radio base station, and the reception timing of the own station is adjusted to the transmission position of the control CH signal in the frame signal, The mobile communication system according to claim 1, wherein frame synchronization is established in a radio section between the local station and the reference radio base station. The reference radio base station is a direct synchronous mobile communication system corresponding to a radio base station synchronized with a private branch exchange,
The radio base station is
A wireless communication system having a wireless slave connected wirelessly to a base station, wherein the wireless base station receives a frame signal including a control CH signal from the reference wireless base station according to a preset synchronization mode The reception timing of the own station is matched with the transmission position of the control CH signal in the frame signal, and frame synchronization in the radio section between the own station and the reference radio base station is established. The mobile communication system according to claim 1. The reference radio base station is a public base station indirect synchronous mobile communication system in which a radio base station that has established frame synchronization in a radio section with a public base station synchronized with a public network is used as a reference radio base station. And
The radio base station is
A wireless communication system having a wireless slave connected wirelessly to a base station, wherein the wireless base station receives a frame signal including a control CH signal from the reference wireless base station according to a preset synchronization mode The reception timing of the own station is matched with the transmission position of the control CH signal in the frame signal, and frame synchronization in the radio section between the own station and the reference radio base station is established. The mobile communication system according to claim 1. The reference radio base station is a direct synchronous mobile communication system corresponding to a radio base station synchronized with a private branch exchange,
The radio base station is
Only when a frame signal including a control CH signal is received from the reference radio base station according to a preset synchronization mode, and the identification ID of the base station has an identification ID that the own station should be a reference station. The frame synchronization in the radio section between the own station and the reference radio base station is established by matching the reception timing of the own station with the transmission position of the control CH signal in the frame signal. The mobile communication system according to 1.

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