JP5084632B2 - Wireless communication system, base station apparatus, dual mode mobile station apparatus, and wireless communication method - Google Patents

Description

  The present invention relates to a radio communication system, a base station apparatus, a dual mode mobile station apparatus, and a radio communication method, and more particularly to allocation of communication channels.

  In recent years, mobile communication systems that employ new wireless communication systems have been introduced one after another. Accordingly, there may be provided a dual mode mobile station corresponding to two different mobile communication systems.

For example, even in PHS (Personal Handy-phone System), the conventional PHS (1.9 GHz band) conforming to the standard defined in Non-Patent Document 1 and the standard conforming to the standard defined in Non-Patent Document 2 are described below. It is planned to provide a dual mode mobile station corresponding to the generation PHS (2.5 GHz band).
"RCR STD-28" 2nd generation cordless telephone system standard "version 5.2", May 29, 2006, Japan Radio Industry Association “ARIB STD-T95“ OFDMA / TDMA TDDBroadband Wireless Access System (Next Generation PHS) ARIB STANDARD ”Version 1.0”, December 12, 2007, Japan Radio Industry Association

  The dual mode mobile station periodically searches each broadcast channel (one of the common control channels) transmitted from the base station of each mobile communication system, and based on the search result (for example, the reception level of the broadcast channel) A connection request (link channel establishment request) for requesting communication channel assignment is made to the base station of either system.

  However, in the above conventional technique, since the dual mode mobile station selects a mobile communication system as a connection destination, when determining a communication channel to be allocated to the dual mode mobile station, the traffic of each base station of each mobile communication system is determined. The situation could not be considered. For this reason, a dual mode mobile station may be denied a connection request from a base station with high traffic (failing to establish a link channel), and it has been necessary to try a connection request to another base station again. .

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a radio communication system, a base station apparatus, a dual mode mobile station apparatus, and a radio communication method that can improve communication channel allocation efficiency. And

  In order to solve the above problems, a radio communication system according to the present invention employs a first base station apparatus and a radio communication system that is close to the first base station apparatus and different from the first base station apparatus. And a dual mode mobile station apparatus compatible with any of the wireless communication schemes employed by the first and second base station apparatuses, wherein the dual mode The mobile station apparatus includes connection request means for transmitting a connection request to the first base station apparatus based on a notification signal transmitted from the first base station apparatus, and the first base station apparatus In response to a connection request from the dual mode mobile station apparatus, resource confirmation means for confirming whether or not the second base station apparatus has an assignable communication channel, and a confirmation result by the resource confirmation means And a channel allocating means for allocating any of the communication channels that can be allocated in the first or second base station apparatus to the dual mode mobile station apparatus. It communicates with said 1st or 2nd base station apparatus using the communication channel allocated by the said base station apparatus.

  According to the present invention, the first base station apparatus that has received the connection request from the dual mode mobile station apparatus assigns one of the communication channels that can be assigned to the first and second base station apparatuses to the dual mode mobile station apparatus. Assign to. That is, in the wireless communication system according to the present invention, when determining the communication channel to be allocated to the dual mode mobile station apparatus, it is possible to consider the traffic conditions of the first and second base station apparatuses. For this reason, the success rate of link channel establishment by a dual mode mobile station apparatus can be raised, and the allocation efficiency of a communication channel can be improved.

  In one aspect of the present invention, when the second base station device has a communication channel that can be allocated, the channel allocation means selects one of the communication channels that can be allocated in the second base station device. When the dual mode mobile station apparatus has no communication channel that can be assigned to the second base station apparatus, any of the assignable communication channels in the first base station apparatus is assigned to the dual mode mobile station. Assign to the device.

  According to this aspect, when both the first base station apparatus and the second base station apparatus have an assignable communication channel, the assignable communication channel in the second base station apparatus is preferentially moved in the dual mode. Can be assigned to stations.

  In the aspect of the present invention, the connection request unit transmits a connection request to the first base station apparatus based on a notification signal transmitted from the second base station apparatus.

  In this aspect, the connection request means includes the base station identification information of the second base station device included in the broadcast signal transmitted from the second base station device to the first base station device, and A connection request including the reception level of the broadcast signal, and the channel allocation means is further configured to further determine, based on the base station identification information and the reception level, included in the connection request from the dual mode mobile station apparatus. Alternatively, any of the assignable communication channels in the second base station apparatus may be assigned to the dual mode mobile station apparatus.

  Also, in this aspect, is the dual mode mobile station device capable of wireless communication with the second base station device based on a reception level of a notification signal transmitted from the second base station device? Communication determination means for determining whether or not the connection request means determines the first base station when the communication determination means determines that wireless communication with the second base station apparatus is possible. A connection request including base station identification information of the second base station device is transmitted to the station device, and the resource confirmation unit responds to the connection request from the dual mode mobile station device by the second base station device. If the base station identification information is included, it may be confirmed whether or not the second base station apparatus has an assignable communication channel.

  In this way, the success rate of link channel establishment by the dual mode mobile station apparatus can be further increased, and the communication channel allocation efficiency can be further improved.

  Further, a base station apparatus according to the present invention is a base station apparatus that adopts a radio communication scheme different from that of a neighboring base station apparatus, and whichever of the neighboring base station apparatus and the radio communication scheme adopted by the base station apparatus is used. In response to a connection request from the corresponding dual mode mobile station apparatus, based on the confirmation result by the resource confirmation means, the resource confirmation means for confirming whether or not the adjacent base station apparatus has an assignable communication channel Channel allocating means for allocating either of the adjacent base station apparatus or a communication channel that can be allocated in the base station apparatus to the dual mode mobile station apparatus.

  Moreover, the dual mode mobile station apparatus according to the present invention employs a first radio communication scheme adopted by the first base station apparatus and a second base station apparatus adjacent to the first base station apparatus. 2 is a dual-mode mobile station device corresponding to the wireless communication system 2 and transmits a connection request to the first base station device based on a notification signal transmitted from the first base station device. The first or second communication channel, which is assigned by the first base station device in response to the connection request, and which can be assigned by the first or second base station device. And wireless communication means for communicating with the second base station apparatus.

  In addition, a wireless communication method according to the present invention includes a first base station device and a second base station that adopts a wireless communication method that is close to the first base station device and is different from the first base station device. A wireless communication method in a wireless communication system, comprising: a dual-mode mobile station apparatus compatible with any of the wireless communication systems employed by the first and second base station apparatuses, A step of transmitting a connection request to the first base station device based on a notification signal transmitted from the first base station device; and In response to a connection request from a mobile station device, the step of confirming whether or not the second base station device has an assignable communication channel, and the first base station device based on the result of the confirmation The first Or assigning any of the assignable communication channels in the second base station apparatus to the dual mode mobile station apparatus, and using the communication channel assigned by the first base station apparatus to the dual mode mobile station apparatus And communicating with the first or second base station apparatus.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an overall configuration diagram of a wireless communication system 10 according to an embodiment of the present invention. As shown in the figure, the wireless communication system 10 is compatible with a conventional PHS of 1.9 GHz band that employs TDMA / TDD (Time Division Multiple Access / Time Division Duplex) method. To a next-generation PHS in the 2.5 GHz band that employs a plurality of conventional base stations 12 (only two are shown here) and a TDMA / TDD scheme and an OFDMA (Orthogonal Frequency Division Multiple Access) scheme A corresponding next-generation base station 14 (only two are shown here) and a dual-mode mobile station 16 corresponding to the conventional PHS and the next-generation PHS are configured. The conventional base station 12 and the next generation base station 14 are connected via a network 18 such as an IP network, and transmit and receive control data, communication data, and the like.

  FIG. 2 is a diagram illustrating a conventional PHS radio channel configuration. As shown in the figure, in the conventional PHS, a 5 ms TDMA frame is divided into eight time slots, of which four slots are uplinks (radio channels from the mobile station to the base station) and the remaining four slots are It is assigned to each downlink (radio channel from the base station to the mobile station). In addition, four uplinks and four downlinks make a pair, and the uplink and downlink making a pair have the same control channel (Control Channel: CCH) or the same information channel (Traffic Channel: TCH). ) Are assigned to each.

  FIG. 3 is a diagram illustrating a radio channel configuration of the next generation PHS. As shown in the figure, in the next-generation PHS, as in the conventional PHS, a 5 ms TDMA frame is divided into 8 time slots, of which 4 slots are uplinks and the remaining 4 slots are downlinks. Assigned. Each radio channel of the next-generation PHS is configured by a combination of one of these time slots and one of the subchannels in the 2.5 GHz band according to the OFDMA method, and each is called a PRU (Physical Resource Unit). Among these, a specific PRU (for example, the uppermost PRU shown in FIG. 3) is a radio channel dedicated to the common channel (CCH), and the other PRUs are ANCHs (individually assigned to each mobile station). It is a radio channel for communication channels such as Anchor Channel) and EXCH (Extra Channel). In addition, the four uplinks and the four downlinks are paired, and the same common channel, the same control channel, or the same information channel is assigned to the paired uplink and downlink, respectively. It has become.

  The dual-mode mobile station 16 can perform radio communication with the conventional base station 12 using the conventional PHS radio channel shown in FIG. 2, and can use the next-generation PHS radio channel shown in FIG. 14 and wireless communication. However, the dual mode mobile station 16 transmits a connection request (link channel establishment request) to the conventional base station 12 when communicating with either the conventional base station 12 or the next generation base station 14.

  The conventional base station 12 that has received the connection request from the dual-mode mobile station 16 confirms whether or not the adjacent next-generation base station 14 has an assignable communication channel, and then assigns an assignable communication channel in the own station. (TCH) or one of the communication channels (ANCH) that can be allocated in the next generation base station 14 close to the own station, and selects the selected communication channel (TCH or ANCH) to the dual mode mobile station 16 .

  That is, in the wireless communication system 10 according to the present embodiment, the traffic conditions of the conventional base station 12 and the next-generation base station 14 can be taken into account when determining the communication channel assigned to the dual mode mobile station 16. Thereby, the success rate of link channel establishment by the dual-mode mobile station 16 is increased, and the communication channel allocation efficiency is improved.

  Below, the structure with which the conventional base station 12 and the dual mode mobile station 16 are provided in order to implement | achieve the said process is demonstrated.

  FIG. 4 is a functional block diagram of the conventional base station 12. As shown in the figure, the conventional base station 12 includes an antenna 20, a radio unit 22, a modem unit 24, a conventional PHS processing unit 26, a network I / F unit 28, and a control unit 30 (channel allocation unit 32, resource confirmation unit). 34).

  The antenna 20 receives a radio signal and outputs the received radio signal to the radio unit 22. Further, the antenna 20 transmits a radio signal supplied from the radio unit 22 to the mobile station. Note that reception and transmission of radio signals are switched every four slots.

  The radio unit 22 includes a low noise amplifier, a power amplifier, a local oscillator, a mixer, and a filter. The radio unit 22 amplifies the radio signal input from the antenna 20 with a low noise amplifier, down-converts the radio signal into an intermediate frequency signal, and outputs the intermediate signal to the modem unit 24. The radio unit 22 up-converts the modulation signal input from the modem unit 24 into a radio signal, amplifies the signal to a transmission output level with a power amplifier, and then supplies the radio signal to the antenna 20.

  The modulation / demodulation unit 24 includes an A / D converter, a D / A converter, a demodulation circuit, and a modulation circuit, and performs modulation / demodulation processing on an input signal in accordance with an instruction from the control unit 30. That is, the modem unit 24 converts the analog received signal input from the radio unit 22 into a digital signal, and outputs the received data extracted from the digital signal by demodulation and decoding to the conventional PHS processing unit 26. Further, the modem unit 24 generates a digital modulation signal based on the frame input from the conventional PHS processing unit 26, and outputs an analog modulation signal corresponding to the generated digital modulation signal to the radio unit 22.

  The conventional PHS processing unit 26 is configured by, for example, a CPU (Central Processing Unit) or a DSP (Digital Signal Processor), and performs data processing based on the conventional PHS protocol on input data in accordance with an instruction from the control unit 30. That is, the conventional PHS processing unit 26 extracts payload data from the received data based on a channel identifier (CI) included in the received data input from the modem unit 24, and extracts the extracted payload data from the network. The data is output to the I / F unit 28. Further, the conventional PHS processing unit 26 stores the payload data input from the network I / F unit 28 in a frame corresponding to the radio channel instructed by the control unit 30, and outputs the frame to the modem unit 24.

  The control unit 30 includes, for example, a CPU and a program that controls the operation of the CPU, and controls each unit of the conventional base station 12. In particular, the control unit 30 functionally includes a channel allocation unit 32 and a resource confirmation unit 34, and can be allocated by the mobile station or the next-generation base station 14 adjacent to the mobile station in response to a link channel establishment request from the mobile station. Assign one of the appropriate communication channels to the mobile station.

  Here, the configuration of the control unit 30 for realizing the above function will be described in more detail with reference to FIG.

  When a link channel establishment request is received (S100), the channel assignment unit 32 selects a communication channel to be assigned to the transmission source according to whether or not the transmission source of the link channel establishment request is the dual mode mobile station 16 Is determined (S102).

  When the transmission source of the link channel establishment request is the dual mode mobile station 16 (S102: Y), the channel allocation unit 32 determines whether or not the next-generation base station 14 close to the own station has a communication channel that can be allocated. The resource confirmation unit 34 is confirmed.

  The resource confirmation unit 34 that has received an instruction from the channel allocation unit 32 is based on the base station identification information (base station ID) of the next generation base station 14 registered in advance as a neighboring base station in a storage unit (not shown). Next generation base station 14 that is close to is identified. Then, the resource confirmation unit 34 transmits a resource acquisition request for confirming whether there is a free resource, that is, an assignable communication channel (ANCH), to the identified next-generation base station 14 (S104). The next-generation base station 14 that has received the resource acquisition request determines whether or not there is an ANCH that can be allocated within the own station (for example, a free channel that is not used for communication and that has a jamming wave level less than a predetermined level). If there is an assignable ANCH, a resource acquisition response including the channel ID of the ANCH is returned, and if there is no assignable ANCH, a resource acquisition response indicating rejection is returned.

  When the resource confirmation unit 34 receives the resource acquisition response from the next generation base station 14 (S106), the resource confirmation unit 34 has an ANCH that can be allocated by the next generation base station 14 that is close to the own station based on the received resource acquisition response. (S108), and notifies the channel allocation unit 32 of the determination result.

  When the next-generation base station 14 close to the own station has an assignable ANCH (S108: Y), the channel assignment unit 32 selects one of these ANCHs (S110), and the base of the next-generation base station 14 The conventional PHS processing unit 26 is instructed to transmit the link channel assignment including the station ID and the channel ID of the selected ANCH to the dual mode mobile station 16 as the transmission source (S112).

  On the other hand, when the transmission source of the link channel establishment request is not the dual mode mobile station 16 (S102: N), or when the next-generation base station 14 close to the own station does not have an assignable ANCH (S108: N), the channel The allocating unit 32 selects any TCH from allocable TCHs within the own station (for example, free channels that are not used for communication whose interference wave level is less than a predetermined value) (S114). The conventional PHS processing unit 26 is instructed to transmit the link channel assignment including the channel ID of the TCH to the source mobile station (S116).

  Thereby, in the dual mode mobile station 16 that has transmitted the link channel establishment request to the conventional base station 12, the ANCH that can be allocated in the next generation base station 14 has priority over the TCH that can be allocated in the conventional base station 12. Assigned to.

  The network I / F unit 28 generates an IP packet by adding a predetermined IP header to the payload data input from the conventional PHS processing unit 26, and the generated IP packet is sent to another conventional base station via the network 18. 12 and the next generation base station 14. Further, the network I / F unit 28 receives IP packets transmitted from other conventional base stations 12 and next-generation base stations 14 via the network 18, and conventionally receives payload data included in the received IP packets. The data is output to the PHS processing unit 26.

  FIG. 5 is a functional block diagram of the dual mode mobile station 16. As shown in the figure, the dual-mode mobile station 16 includes an antenna 40, a radio unit 42, a modem unit 44, a conventional PHS processing unit 46, a next-generation PHS processing unit 48, and a control unit 50 (base station information acquisition unit 52, communication A control unit 54) and an upper protocol I / F unit 56.

  The antenna 40 receives a radio signal and outputs the received radio signal to the radio unit 42. Further, the antenna 40 transmits a radio signal supplied from the radio unit 42 to the conventional base station 12 or the next generation base station 14. Note that reception and transmission of radio signals are switched every four slots.

  The radio unit 42 includes a low noise amplifier, a power amplifier, a local oscillator, a mixer, and a filter. The radio unit 42 amplifies the radio signal input from the antenna 40 with a low noise amplifier, down-converts it to an intermediate frequency signal, and outputs the intermediate signal to the modem unit 44. The radio unit 42 up-converts the modulation signal input from the modulation / demodulation unit 44 into a radio signal, amplifies it to a transmission output level with a power amplifier, and supplies the signal to the antenna 40.

  The modem unit 44 includes an A / D converter, a D / A converter, a serial-parallel converter, a parallel-serial converter, an FFT (Fast Fourier Transform) operation unit, and an IFFT (Inverse Fast Fourier Transform). (Fourier transform) A calculation unit is included, and modulation / demodulation processing according to the type of the input signal is performed in accordance with an instruction from the control unit 50.

  That is, when the frequency of the analog reception signal input from the radio unit 42 to the modem unit 44 is a frequency corresponding to the conventional PHS, the modem unit 44 converts the analog signal into a digital signal, and digitally demodulates and decodes the digital signal. The received data extracted from the signal is output to the conventional PHS processing unit 46.

  Further, the modem unit 44 generates a digital modulation signal based on the frame input from the conventional PHS processing unit 46, and outputs an analog modulation signal corresponding to the generated digital modulation signal to the radio unit 42.

  On the other hand, when the frequency of the analog reception signal input from the wireless unit 42 to the modem unit 44 is a frequency corresponding to the next generation PHS, the modem unit 44 adds GI (Guard Interval) to the analog signal. Removal, A / D conversion, serial / parallel conversion, discrete Fourier transform, parallel / serial conversion, and the like are performed to obtain a continuous complex symbol sequence. Then, the modem unit 44 extracts a data bit sequence (received data) corresponding to the symbol modulation scheme from the obtained complex symbol sequence, and outputs the extracted received data to the next generation PHS processing unit 48.

  Further, the modem unit 44 performs symbol mapping (assignment of amplitude and phase) according to the modulation scheme specified by the control unit 50 on the frame input from the next-generation PHS processing unit 48, and converts the complex symbol sequence to obtain. Then, the modem unit 44 performs serial-parallel conversion, inverse discrete Fourier transform, parallel-serial conversion, D / A conversion, and the like on the obtained complex symbol sequence, and outputs a signal obtained by adding GI to the generated baseband OFDM signal. Output to the radio unit 42.

  The conventional PHS processing unit 46 is constituted by, for example, a CPU or a DSP, and performs data processing based on the conventional PHS protocol on input data in accordance with an instruction from the control unit 50. That is, the conventional PHS processing unit 46 extracts the payload data from the received data based on the channel identifier (CI) included in the received data input from the modem unit 44, and extracts the extracted payload data as the upper protocol I. / F unit 56 outputs. Further, the conventional PHS processing unit 46 stores the payload data input from the upper protocol I / F unit 56 in a frame corresponding to a radio channel (CCH, TCH, etc.) instructed by the control unit 50, and stores the frame. The result is output to the modem unit 44.

  The next-generation PHS processing unit 48 is configured by, for example, a CPU or a DSP, and performs data processing based on the next-generation PHS protocol on input data in accordance with an instruction from the control unit 50. That is, the next-generation PHS processing unit 48 extracts payload data from the received data based on a channel identifier (CI) included in the received data input from the modem unit 44, and uses the extracted payload data as a higher-level protocol. Output to the I / F unit 56. Further, the next generation PHS processing unit 48 stores the transmission data input from the upper protocol I / F unit 56 in a frame corresponding to a radio channel (ANCH, EXCH, etc.) instructed by the control unit 50, and the frame Is output to the modem unit 44.

  The control unit 50 includes, for example, a CPU and a program for controlling the operation of the CPU, and controls each unit of the dual mode mobile station 16 so that the dual mode mobile station 16 is compatible with both conventional PHS and next generation PHS systems. In particular, the control unit 50 functionally includes a base station information acquisition unit 52 and a communication control unit 54, and controls a series of processes related to communication with the conventional base station 12 or the next-generation base station 14.

  The base station information acquisition unit 52 is a broadcast channel (one of the control channels (CCH)) periodically transmitted from the conventional base station 12 or a broadcast channel periodically transmitted from the next generation base station 14 ( A common channel (one of the common channels (CCH)) is received, and the reception level of the received broadcast channel and the base station ID included in the broadcast channel are acquired.

  When the dual mode mobile station 16 communicates with either the conventional base station 12 or the next generation base station 14, the communication control unit 54 is based on the broadcast channel reception level acquired by the base station information acquisition unit 52. A link channel establishment request is transmitted to the selected conventional base station 12. For example, the communication control unit 54 selects the conventional base station 12 that is the transmission source of the broadcast channel with the highest reception level as the transmission destination of the link channel establishment request. Then, the communication control unit 54 instructs the conventional PHS processing unit 46 to transmit a link channel establishment request to the selected conventional base station 12.

  Further, when the link control unit 54 receives the link channel assignment from the conventional base station 12, the communication control unit 54 uses the communication channel (TCH or ANCH) identified by the channel ID included in the link channel assignment. Alternatively, the conventional PHS processing unit 46 is instructed to communicate with the next-generation base station 14.

  Specifically, when only the channel ID is included in the received link channel assignment, the communication control unit 54 uses the TCH identified by the channel ID and the conventional base station 12 that is the transmission source of the link channel assignment. The conventional PHS processing unit 46 is instructed to perform communication. On the other hand, when the received link channel assignment includes a base station ID and a channel ID, the communication control unit 54 uses the ANCH identified by the channel ID to identify the next generation base station 14 identified by the base station ID. To the next-generation PHS processing unit 48.

  The upper protocol I / F unit 56 supplies payload data input from the conventional PHS processing unit 46 or the next generation PHS processing unit 48 to an upper layer (not shown). Further, the upper protocol I / F unit 56 outputs transmission data input from an upper layer (not shown) to the conventional PHS processing unit 46 or the next generation PHS processing unit 48.

  Next, it is performed between the conventional base station 12, the next generation base station 14 (here, only the next generation base stations 14-1 and 14-2 adjacent to the conventional base station 12 are shown), and the dual mode mobile station 16. An example of communication channel assignment processing will be described with reference to the sequence diagram shown in FIG.

  As shown in the figure, the conventional base station 12 and the next-generation base stations 14-1 and 14-2 regularly transmit broadcast channels including their own base station IDs (S200 to S204). The dual-mode mobile station 16 that has received these broadcast channels acquires the received broadcast channel reception level and the base station ID included in the broadcast channel (S206).

  When the dual mode mobile station 16 starts communication, the dual mode mobile station 16 selects the conventional base station 12 selected based on the reception level of the broadcast channel acquired in S206 (for example, the transmission source of the broadcast channel with the highest reception level). The link channel establishment request is transmitted (S208).

  When receiving the link channel establishment request from the dual-mode mobile station 16, the conventional base station 12 transmits resource acquisition requests to the next-generation base stations 14-1 and 14-2 registered in advance as neighboring base stations. (S210, S212).

  The next-generation base stations 14-1 and 14-2 that have received the link channel establishment request confirm whether or not there is an assignable ANCH in their own station, and if there is an assignable ANCH, the channel of that ANCH. A resource acquisition response including the ID is returned to the conventional base station 12, and if there is no assignable ANCH, a resource acquisition response indicating rejection is returned to the conventional base station 12 (S214, S216).

  When receiving the resource acquisition responses from the next generation base stations 14-1 and 14-2, the conventional base station 12 determines a communication channel to be allocated to the dual mode mobile station 16 based on the resource acquisition responses (S218). . That is, when the conventional base station 12 has an ANCH that can be assigned by either of the next-generation base stations 14-1 and 14-2, any one of those ANCHs (for example, one having the minimum jamming wave level). Is a communication channel to be assigned to the dual mode mobile station 16, and neither of the next generation base stations 14-1 and 14-2 has an assignable ANCH, The communication channel assigned to the dual-mode mobile station 16 is the one having the minimum disturbing wave level).

  Then, the conventional base station 12 transmits the link channel assignment including the channel ID of the communication channel (TCH or ANCH) determined in S218 to the dual mode mobile station 16 (S220). When the communication channel determined in S218 is ANCH, the link channel assignment transmitted in S220 further includes the base station ID of the next generation base station 14-1 or 14-2 having the ANCH.

  The dual mode mobile station 16 that has received the link channel assignment from the conventional base station 12 receives the communication channel (TCH or ANCH) identified by the conventional base station 12 or the next-generation base station 14 and the channel ID included in the link channel assignment. ) Is established (S222). Specifically, when only the channel ID is included in the received link channel assignment, the dual mode mobile station 16 establishes a TCH identified by the channel ID with the conventional base station 12.

  On the other hand, if the received link channel assignment includes a base station ID and a channel ID, the dual-mode mobile station 16 determines that the next-generation base station 14-1 or 14-2 identified by the base station ID and the channel An ANCH identified by the ID is established. In this case, TDMA frame synchronization is established between the conventional base station 12 and the next-generation base stations 14-1 and 14-2, and the dual-mode mobile station 16 is based on the notification signal received in S200. If the downlink frame synchronization is established with the base station 12, the dual mode mobile station 16 can omit the uplink frame synchronization establishment process with the next generation base station 14-1 or 14-2.

  The dual-mode mobile station 16 wirelessly communicates with the next-generation base station 14-1 or 14-2 based on the reception level of the notification level from the next-generation base station 14-1 or 14-2 acquired in S206. It is determined whether or not communication is possible (for example, whether or not the reception level is equal to or higher than a predetermined level). In S208, the base station ID of the next generation base station 14 determined to be capable of wireless communication is determined. A link channel establishment request including this may be transmitted to the conventional base station 12. In this way, the conventional base station 12 only needs to transmit a resource confirmation request to the next-generation base station 14 identified by the base station ID included in the link channel establishment request, thus reducing the processing load for resource confirmation. can do. Further, the conventional base station 12 can assign an ANCH that is highly likely to succeed in establishing a link channel to the dual mode mobile station 16.

  Further, in S208, the dual-mode mobile station 16 includes a link including the base station IDs of the next generation base stations 14-1 and 14-2 acquired in S206 and the reception level of the notification level transmitted from those base stations. A channel establishment request may be transmitted to the conventional base station 12. Then, in S218, the conventional base station 12 may determine a communication channel to be allocated to the dual mode mobile station 16 based further on the base station ID and the reception level included in the link channel establishment request. In this way, the conventional base station 12 can assign an ANCH that is likely to succeed in establishing a link channel to the dual mode mobile station 16.

  Further, the dual mode mobile station 16 may specify an ANCH with good communication quality by carrier sense, for example, and may transmit a link channel establishment request specifying the specified ANCH to the conventional base station 12 in S208. In this way, the conventional base station 12 can assign an ANCH that is more likely to succeed in establishing a link channel to the dual mode mobile station 16.

  According to the radio communication system 10 described above, the communication channel to be allocated to the dual mode mobile station 16 is determined based on the traffic conditions (presence / absence of an assignable communication channel) of the conventional base station 12 and the next generation base station 14. can do. Therefore, the success rate of link channel establishment by the dual mode mobile station 16 can be increased, and the communication channel allocation efficiency can be improved.

  The present invention is not limited to the above embodiment.

  For example, the present invention includes a first base station, a second base station that is close to the first base station and adopts a wireless communication scheme different from the first base station, and the first and second base stations. The present invention can be widely applied to all wireless communication systems including dual mode mobile stations compatible with any of the wireless communication systems employed by the.

It is a block diagram of the radio | wireless communications system which concerns on embodiment of this invention. It is a figure which shows the radio channel structure of conventional PHS. It is a figure which shows the radio channel structure of next generation PHS. It is a functional block diagram of the next generation base station which concerns on embodiment of this invention. It is a functional block diagram of the dual mode mobile station which concerns on embodiment of this invention. It is a flowchart which shows an example of the allocation process of the communication channel which concerns on embodiment of this invention. It is a sequence diagram which shows an example of the allocation process of the communication channel which concerns on embodiment of this invention.

Explanation of symbols

  10 wireless communication systems, 12 conventional base stations, 14 next-generation base stations, 16 dual-mode mobile stations, 18 networks, 20, 40 antennas, 22, 42 radio units, 24, 44 modem units, 26, 46 conventional PHS processing units, 28 Network I / F unit, 30, 50 control unit, 32 channel allocation unit, 34 resource confirmation unit, 48 next generation PHS processing unit, 52 base station information acquisition unit, 54 communication control unit, 56 upper protocol I / F unit.

Claims (8)

A first base station apparatus, a second base station apparatus that is close to the first base station apparatus and adopts a radio communication scheme different from the first base station apparatus, and the first and second bases A dual-mode mobile station device that supports any of the wireless communication methods employed by the station device,
The dual mode mobile station apparatus is:
Connection request means for transmitting a connection request to the first base station device based on a notification signal transmitted from the first base station device;
The first base station apparatus
Resource confirmation means for confirming whether or not the second base station apparatus has an assignable communication channel in response to a connection request from the dual mode mobile station apparatus;
Channel allocating means for allocating, to the dual mode mobile station apparatus, any communication channel that can be allocated in the first or second base station apparatus, based on a confirmation result by the resource confirming means;
Including
The dual mode mobile station apparatus communicates with the first or second base station apparatus using a communication channel assigned by the first base station apparatus.
A wireless communication system. The wireless communication system according to claim 1,
The channel allocation means is
When the second base station device has an assignable communication channel, assign one of the assignable communication channels in the second base station device to the dual mode mobile station device,
When the second base station device does not have an assignable communication channel, assign any of the assignable communication channels in the first base station device to the dual mode mobile station device.
A wireless communication system. The wireless communication system according to claim 1 or 2,
The connection request means further transmits a connection request to the first base station device based on a notification signal transmitted from the second base station device;
A wireless communication system. The wireless communication system according to claim 3,
The connection requesting unit is configured to send base station identification information of the second base station device included in a broadcast signal transmitted from the second base station device to the first base station device and the broadcast signal. Send a connection request including the receive level,
The channel allocating means may further determine which of the communication channels allocatable in the first or second base station apparatus is further based on the base station identification information and the reception level included in the connection request from the dual mode mobile station apparatus. Assigning to the dual mode mobile station device,
A wireless communication system. The wireless communication system according to claim 3,
The dual mode mobile station apparatus is:
Communication determining means for determining whether wireless communication with the second base station apparatus is possible based on a reception level of a notification signal transmitted from the second base station apparatus;
Further including
The connection requesting unit is configured to send the second base station device to the first base station device when the communication determining unit determines that wireless communication with the second base station device is possible. Send a connection request containing base station identification information for
The resource confirmation unit has a communication channel that can be allocated by the second base station apparatus when the connection request from the dual mode mobile station apparatus includes base station identification information of the second base station apparatus. Check whether or not,
A wireless communication system. A base station device that adopts a wireless communication method different from the neighboring base station device,
Whether the neighboring base station apparatus has a communication channel that can be allocated in response to a connection request from a dual-mode mobile station apparatus that supports both the neighboring base station apparatus and the wireless communication method adopted by the base station apparatus A resource confirmation means for confirming,
Channel allocation means for allocating to the dual mode mobile station apparatus any of the communication channels that can be allocated in the neighboring base station apparatus or the base station apparatus based on the confirmation result by the resource confirmation means;
A base station apparatus comprising: Dual mode movement corresponding to the first radio communication system adopted by the first base station apparatus and the second radio communication system adopted by the second base station apparatus close to the first base station apparatus A station device,
Connection request means for transmitting a connection request to the first base station apparatus based on a notification signal transmitted from the first base station apparatus;
The first or second base station apparatus using any of the communication channels that can be allocated in the first or second base station apparatus that is allocated by the first base station apparatus in response to the connection request. Wireless communication means for communicating with;
A dual-mode mobile station apparatus. A first base station apparatus, a second base station apparatus that is close to the first base station apparatus and adopts a radio communication scheme different from the first base station apparatus, and the first and second bases A wireless communication method in a wireless communication system including a dual-mode mobile station device that supports any of the wireless communication methods employed by the station device,
The dual mode mobile station apparatus transmits a connection request to the first base station apparatus based on a notification signal transmitted from the first base station apparatus;
The first base station apparatus confirming whether or not the second base station apparatus has an assignable communication channel in response to a connection request from the dual mode mobile station apparatus;
The first base station apparatus assigning to the dual-mode mobile station apparatus one of the assignable communication channels in the first or second base station apparatus based on the result of the confirmation;
The dual mode mobile station apparatus communicates with the first or second base station apparatus using a communication channel assigned by the first base station apparatus;
A wireless communication method comprising:

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