JP2006270524A - Mobile radio terminal unit, radio base station, and mobile communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable common use between an existing public mobile communication system and a proprietary mobile communication system with a relatively low cost. <P>SOLUTION: A signal received from a mobile station unit in a receiving RF section 120 is inverse spread in inverse spreading sections 1211-121m, among which a high level signal is selected by a selection section 124 and demodulated in a demodulating section 125. Meanwhile, as to transmission to the mobile station unit, a signal primarily modulated in a modulating section 111 is secondarily modulated in a spreading section 112, and further frequency modulated in a transmitting RF section 113 and radio transmitted. In the spreading section 112, channelization spreading and scrambling spreading processing specified in a W-CDMA communication system being used for the public mobile communication system are performed in a first spreading section 112a, and further, spreading processing is performed in a second spreading section 112b. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a mobile radio terminal apparatus, a radio base station apparatus, and a mobile communication system used in a mobile communication system employing a CDMA (Code Division Multiple Access) system.

  As is well known, in a CDMA mobile communication system composed of a plurality of base stations and a plurality of mobile stations, each base station performs downlink transmission using a carrier frequency and a scramble spreading code assigned to the base station. . Cell design is performed by combining these two, and the base stations of each other are installed so that radio waves do not interfere with each other. In addition, the mobile station finds a base station to be a communication partner based on the reception level of the downlink carrier signal and the scramble spreading code.

  If the base station has a high density of mobile stations in its own cell and the capacity of the base station cannot be covered, the base station can either increase the spreading capacity so that more channelization processing can be performed, or Is insufficient by adding another carrier signal with a different frequency. Of course, this carrier signal having a different frequency is selected so as not to cause radio wave interference by using a signal different from the frequency used in the surrounding base station.

  Thus, although a CDMA mobile communication system is established, providing a mobile communication system having a different management system in a carrier frequency band approved by each communication carrier helps an exchange located above the base station. It becomes necessary (see, for example, Non-Patent Document 1).

  For example, when a private network having a management system different from that of a mobile communication system (public mobile communication network) operated by a telecommunications carrier is to be built in a certain office building, the system uses a mobile station within the office building. It is necessary to perform a process for determining whether a call is a public mobile communication or a private communication by referring to a subscriber database included in the exchange, and distinguishing the type of communication for each call. This imposes an extra processing burden on the exchange.

  In addition, when connecting to the base station of the office building and the exchange outside the building through the entrance line, the traffic amount of the entrance line increases due to the processing for distinguishing the type as described above. Measures to increase are needed. In addition, borrowing an entrance line from another company will increase the borrowing fee.

As another implementation method, it is conceivable to construct a wireless local area network using an ISM band wireless LAN that does not require use authorization. In this case, since the carrier frequency band is different, it can be used without radio wave interference with the above public mobile communication, but since the ISM band is a frequency band that anyone can use, Another problem is that it cannot avoid radio wave interference. In addition, it is necessary to configure the mobile station so that it can be used in a plurality of bands.
"Nikkei Communication 2003.9.8 No.398", Nikkei Business Publications, September 8, 2003, p. 52-62.

  Conventionally, for example, when an original mobile communication system is to be constructed in an office building, if the same band is used, the operation cost becomes high. There was a problem that interference could occur.

  The present invention has been made to solve the above-described problem, and can be realized at a relatively low cost, and can be shared with an existing public mobile communication system and an original mobile communication system, a mobile radio terminal apparatus, a radio base station apparatus, and An object is to provide a mobile communication system.

  In order to achieve the above object, the present invention is used in a mobile communication system adopting a CDMA system, and in a radio base station apparatus that performs radio communication with a mobile radio terminal apparatus, transmission information is spread using a first spreading code. The first spreading means for modulating, the second spreading means for spreading and modulating the modulation result obtained from the first spreading means using the second spreading code, and the modulation result obtained from the second spreading means as the mobile radio terminal apparatus And a transmission means for wireless transmission.

  The present invention also relates to a mobile radio terminal device used in a mobile communication system adopting a CDMA system and wirelessly communicating with a radio base station device connected to a network, receiving a radio signal from the radio base station device, Receiving means for frequency conversion, first despreading means for despreading the output signal of the receiving means using the first spreading code, and despreading the output signal of the first despreading means using the second spreading code And a second despreading means.

  Furthermore, the present invention provides a mobile communication system in which a mobile radio terminal apparatus and a radio base station apparatus perform radio communication using a CDMA system, wherein the radio base station apparatus performs first modulation for spreading transmission information using a first spreading code. Means, second spreading means for spreading and modulating the modulation result obtained from the first spreading means using the second spreading code, and wirelessly transmitting the modulation result obtained from the second spreading means to the mobile radio terminal apparatus The mobile radio terminal apparatus receives a radio signal from the radio base station apparatus, and frequency-converts the radio signal from the radio base station apparatus, and despreads the output signal of the reception means using a second spreading code. The first despreading means and a second despreading means for despreading the output signal of the first despreading means using the first spreading code are provided.

  As described above, according to the present invention, in the radio base station apparatus, similarly to the public radio base station connected to the public network, spread modulation is performed using the first spreading code, and further, the second spreading code is used. Then, spread modulation is performed to perform radio transmission toward the mobile radio terminal apparatus, and the mobile radio terminal apparatus performs despreading corresponding to the two spread modulations.

  Therefore, according to the present invention, in addition to the conventional spreading / despreading, another spreading / despreading is performed, so that the same frequency band as that used for communication with the public radio base station can be used. Therefore, it is possible to provide a mobile radio terminal apparatus, a radio base station apparatus, and a mobile communication system that can be implemented at a relatively low cost and can share an existing public mobile communication system and an original mobile communication system.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows the configuration of a local base station apparatus of a mobile communication system according to the first embodiment of the present invention.

  The local base station apparatus includes an antenna 101, a duplexer 102, a control unit 100a, a radio frame configuration unit 110, a modulation unit 111, a spreading unit 112, a transmission RF unit 113, a reception RF unit 120, Despreading units 1211 to 121m, level measuring units 1221 to 122m, a level comparison unit 123, a selection unit 124, and a demodulation unit 125 are provided.

  The control unit 100a controls each part of the local base station apparatus, calculates the number of bits of the radio frame, the spreading code, the spreading factor, and the amplification factor, and sends the information to each part that needs the information. By supplying each, the number of bits, spreading code, spreading factor, and amplification factor are controlled.

  As the spreading code, two kinds of spreading codes are designated for transmission, and one kind of spreading code is designated for reception. As the spreading factor, a spreading factor suitable for the amount of transmission information to be transmitted is selected.

  The radio frame configuration unit 110 generates a radio frame by inserting transmission information into a radio frame having the number of bits specified by the control unit 100a. Modulation section 111 performs primary modulation on the radio frame generated by radio frame configuration section 110 and outputs the modulation result to spreading section 112.

  The diffusion unit 112 plays a role of secondary modulation, and includes a first diffusion unit 112a and a second diffusion unit 112b. First, the first spreading unit 112a similarly performs spread modulation on the modulation result of the modulating unit 111 with one spreading code designated by the control unit 100a at a spreading factor designated by the control unit 100a.

  The first spreading unit 112a performs processing corresponding to channelization spreading and scramble spreading processing defined by the W-CDMA communication method used in the public mobile communication system, and is a spreading factor designated by the control unit 100a. Is the same as the spreading factor used in the public mobile communication system, and is one of a plurality of predetermined values, such as spreading factors 64, 128, and 256, for example. Note that the spreading factor is the ratio of the number of spreading code chips (spreading chip rate) to one bit (information bit rate) of a radio frame.

  Then, the signal spread-modulated by the first spreading unit 112a is similarly transmitted at the spreading factor designated by the control unit 100a using the other spreading code designated by the control unit 100a by the second spreading unit 112b. Perform spread modulation. This modulation result is output to transmission RF section 113.

  Here, the spreading factor assigned to the second spreading unit 112b by the control unit 100a is taken into consideration so that the frequency bandwidth is not excessively widened, and the public mobility is set to one of a plurality of predetermined values. The value is smaller than the spreading factor used in the communication system, for example, a spreading factor of 2 or 4. When the spreading factor is 2, two types of spreading codes are used, and when the spreading factor is 4, four types of spreading codes are used.

  The transmission RF unit 113 up-converts the modulation result of the second spreading unit 112b to the radio frequency of the band used in the public mobile communication system specified by the control unit 100a, and amplifies it with the amplification factor specified by the control unit 100a To do. The radio signal generated in this way is transmitted from the antenna 101 to the mobile station apparatus described later through the duplexer 102.

  On the other hand, a radio signal transmitted from the mobile station apparatus is received by the antenna 101 and input to the reception RF unit 120 through the duplexer 102. In the reception RF unit 120, the radio signal in the carrier frequency band designated by the control unit 100a is down-converted to an intermediate frequency, amplified, and then input to the despreading units 1211 to 121m.

  The despreading units 1211 to 121m perform processing corresponding to channelization despreading and scrambled despreading processing defined by the W-CDMA communication method used in the public mobile communication system, and are designated by the control unit 100a. The received signal output from the reception RF unit 120 is despread using the spreading code.

  The despreading units 1211 to 121m correspond to the spreading rates used in the mobile station devices described later. That is, m corresponds to the number of types of spreading factors used in the mobile station apparatus described later. For example, if there are three spreading factors, m is 3. A signal obtained by the despreading process is input to the selection unit 124 and the corresponding level measurement units 1221 to 122m.

  The level measurement units 1221 to 122m measure the levels of signals input from the corresponding despreading units 1211 to 121m, and output the measurement results to the level comparison unit 123. The level comparison unit 123 compares the measurement results input from the level measurement units 1221 to 122m, detects a signal having the largest signal level, and notifies the selection unit 124 of information for identifying the signal.

  The selection unit 124 selects a signal specified by the identification information from the level comparison unit 123 among the signals input from the despreading units 1211 to 121m, and outputs this to the demodulation unit 125. Demodulation section 125 performs data demodulation corresponding to primary modulation in a mobile station apparatus to be described later, acquires reception information, and outputs the received information to a subsequent data processing section (not shown).

Next, the configuration of the mobile station apparatus of the mobile communication system according to the first embodiment of the present invention will be described with reference to FIG.
The mobile station apparatus includes an antenna 201, a duplexer 202, a control unit 200a, a radio frame configuration unit 210, a modulation unit 211, a spreading unit 212, a transmission RF unit 213, a reception RF unit 220, and a reverse A diffusion unit 230 and a demodulation unit 221 are provided.

  The control unit 200a controls each unit of the mobile station apparatus in an integrated manner, and according to mode settings set by the user through a key operation unit (not shown), the number of bits of the radio frame, the spreading code, and the spreading factor The number of bits, the spreading code, the spreading factor, and the amplification factor are controlled by calculating the amplification factor and supplying the information to each unit that requires the information.

  As the spreading code, one kind of spreading code is designated for transmission, and two kinds of spreading codes are designated for reception. As the spreading factor, a spreading factor suitable for the amount of transmission information to be transmitted is selected.

  The radio frame configuration unit 210 generates a radio frame by inserting transmission information into a radio frame having the number of bits specified by the control unit 200a. Modulation section 211 performs primary modulation on the radio frame generated by radio frame configuration section 210 and outputs the modulation result to spreading section 212.

  The spreading unit 212 plays a role of secondary modulation, and performs processing corresponding to channelization spreading and scramble spreading processing defined by the W-CDMA communication method used in the public mobile communication system.

  Spreading section 212 similarly spread-modulates the modulation result of modulating section 211 with the spreading factor specified by control section 200a, using one spreading code specified by control section 200a. Here, the spreading code designated by the control unit 200a is used properly depending on whether the address is for the local base station apparatus or the public base station apparatus, depending on the mode setting.

  The spreading factor designated by the control unit 200a is the same as the spreading factor used in the public mobile communication system, and is one of a plurality of predetermined values, such as spreading factors 64, 128, 256, for example. It is.

  The transmission RF unit 213 up-converts the modulation result of the spreading unit 212 to a radio frequency in a band used in the public mobile communication system specified by the control unit 200a, and amplifies it with the amplification factor specified by the control unit 200a. The wireless signal generated in this way is transmitted from the antenna 201 through the duplexer 202 to the above-described local base station apparatus and public base station apparatus used in the public mobile communication system.

  On the other hand, a radio signal transmitted from the above-described local base station apparatus or the public base station apparatus is received by the antenna 201 and input to the reception RF unit 120 through the duplexer 202. In the reception RF unit 120, the radio signal in the carrier frequency band specified by the control unit 200a is down-converted to an intermediate frequency, amplified, and then input to the despreading unit 230.

  The despreading unit 230 selects one of the radio signal transmitted from the above-described local base station device and the radio signal transmitted from the public base station device according to the mode setting designated by the control unit 200a. It selectively despreads and is configured as shown in FIG. 3, for example.

  The despreading unit 230 includes a switching unit 2300, first despreading units 2311 to 231n, first level measurement units 2321 to 232n, a first level comparison unit 233, a first selection unit 234, and a second despreading unit. Units 2351 to 235o, second level measurement units 2361 to 236o, a second level comparison unit 237, and a second selection unit 238.

  The switching unit 2300 outputs the received signal to the first despreading units 2311 to 231n when the reception signal output from the reception RF unit 220 is input and the local mode is designated from the control unit 200a. When the public mode is designated from the control unit 200a, the received signal is output to the second despreading units 2351 to 235o in the subsequent stage.

  That is, when the public mode is designated, the first despreading units 2311 to 231n, the first level measurement units 2321 to 232n, the first level comparison unit 233, and the first selection unit 234 are bypassed.

  The first despreading units 2311 to 231n perform the despreading process corresponding to the second spreading unit 112b of the local base station apparatus described above, and use the spreading code specified by the control unit 200a to switch the switching unit 2300. The received signal output from is despreaded.

  The first despreading units 2311 to 231n correspond to the spreading rates used in the second diffusion unit 112b. That is, n corresponds to the number of types of diffusivities used in the second diffusing unit 112b. For example, if there are three diffusivities, n is 3. A signal obtained by the despreading process is input to the first selection unit 234 and the corresponding first level measurement units 2321 to 232n.

  The first level measurement units 2321 to 232n measure the levels of the signals input from the corresponding first despreading units 2311 to 231n, and output the measurement results to the first level comparison unit 233.

  The first level comparison unit 233 compares the measurement results input from the first level measurement units 2321 to 232n, detects the signal having the highest signal level, and notifies the first selection unit 234 of information for identifying the signal. To do.

  The first selection unit 234 selects a signal specified by the identification information from the level comparison unit 233 from among the signals input from the first despreading units 2311 to 231n, and selects the selected signal as the second despreading unit. 2351 to 235o.

  The second despreading units 2351 to 235o correspond to the first spreading unit 112a of the private base station apparatus described above, and are channelization reverses defined by the W-CDMA communication method used in the public mobile communication system. A process corresponding to the spreading and scrambled despreading process is performed, and the signal output from the first selection unit 234 or the switching unit 2300 is reversed using the spreading code specified by the control unit 200a. Diffusion processing.

  The second despreading units 2351 to 235o correspond to the spreading factors used in the first diffusion unit 112a. That is, o corresponds to the number of types of spreading factors used in the first spreading unit 112a. For example, when there are three spreading factors, o is 3. The signal obtained by the despreading process is input to the second selection unit 238 and the corresponding second level measurement units 2361 to 236o.

  The second level measurement units 2361 to 236o measure the levels of the signals input from the corresponding second despreading units 2351 to 235o, and output the measurement results to the second level comparison unit 237.

  The second level comparison unit 237 compares the measurement results input from the second level measurement units 2361 to 236o, detects the signal having the highest signal level, and notifies the second selection unit 238 of information for identifying the signal. To do.

  The second selection unit 238 selects a signal specified by the identification information from the level comparison unit 233 among the signals input from the first despreading units 2311 to 231n, and selects the selected signal from the demodulation unit 221 at the subsequent stage. Output to.

  The demodulator 221 performs data demodulation corresponding to the primary modulation of the local base station apparatus and the public base station apparatus described above to acquire reception information, and outputs the received information to a subsequent data processing unit (not shown).

  As described above, in the mobile communication system configured as described above, when a mobile station apparatus communicates with a public base station apparatus, a mode setting using the public mode is made in advance by the user, and the switching unit 2300 is switched and controlled. As a despreading process corresponding to a radio signal from a public base station apparatus using a despreading unit 2351 to 235o, a second level measurement unit 2361 to 236o, a second level comparison unit 237, and a second selection unit 238, public mobile communication Channelization despreading and scrambled despreading processing specified by the W-CDMA communication system used in the system is performed for reception.

  For transmission, the mobile station apparatus uses a spreading code addressed to the public base station apparatus in the spreading unit 212, and channelization spread and scramble spread processing defined by the W-CDMA communication method used in the public mobile communication system. To generate a radio signal with the transmission target as a public base station apparatus.

  That is, the mobile station apparatus performs switching setting of the switching unit 2300 in accordance with the public mode setting, selects a circuit necessary for communication with the public base station apparatus, and uses the spread code addressed to the public base station apparatus. Wireless signals are transmitted and received. Thereby, the mobile station apparatus can perform public wireless communication through the public base station apparatus as in the conventional case.

  On the other hand, when the mobile station apparatus communicates with the local base station apparatus, the local base station apparatus uses the first spreading unit 112a to perform channelization spreading defined by the W-CDMA communication method used in the public mobile communication system. In addition to this, the scramble spreading process is performed, and in addition to this, the second spreading unit 112b further performs a spreading process to perform wireless transmission.

  On the other hand, in the mobile station apparatus, mode setting using the premise mode is made in advance by the user, and the switching unit 2300 is switched and controlled, and the first despreading units 2311 to 231n, the first level measuring units 2321 to 232n, and the first level are controlled. The comparison unit 233 and the first selection unit 234 are used to perform the despreading process corresponding to the second spreading unit 112b of the local base station apparatus, and then the second despreading units 2351 to 235o and the second level measuring unit 2361 ˜236o, the second level comparison unit 237, and the second selection unit 238 are used to perform reception by performing a despreading process corresponding to the first spreading unit 112a of the local base station apparatus.

  For transmission, the mobile station apparatus uses a spreading code addressed to the local base station apparatus in spreading section 212, and channelization spreading and scramble spreading processing defined in the W-CDMA communication system used in the public mobile communication system. To generate a radio signal with the transmission target as the local base station apparatus.

  On the other hand, the local base station apparatus uses the despreading units 1211 to 121m, the level measurement units 1221 to 122m, the level comparison unit 123, and the selection unit 124 to perform the despreading process corresponding to the spreading unit 212 of the mobile station apparatus. To implement.

  That is, communication from the mobile station device to the local base station device is performed by one spreading process as in the case of communication with the public base station device, while the local base station device to the mobile station device is in addition to the above spreading process. In addition, another spreading process is performed for communication. Thereby, the mobile station apparatus can perform private wireless communication through the carrier frequency band used by the public base station apparatus.

  FIG. 4 shows an image of the carrier signal spectrum transmitted from the local base station device (FIG. 4A) and an image diagram of the carrier signal spectrum obtained by the despreading process of the mobile station device (FIG. 4B). . In this figure, an example is shown in which four waves of bandwidth W are used in public wireless communication, and spread processing is further quadrupled in private wireless communication.

  FIG. 4A shows a situation in which the carrier signal B is used among the four waves of the carrier signals A to D by public wireless communication, and the carrier signal E is used by the local base station apparatus. . Since the carrier signal E is spread four times with respect to the carrier signal B, the power density is 6 dB lower.

  For this reason, when the reception level is detected with the bandwidth W in the mobile station apparatus, the carrier signal B is dominant, and this carrier signal B is selected and subjected to W-CDMA despreading processing and demodulation processing.

  On the other hand, when the first despreading units 2311 to 231n perform the despreading process in the mobile station apparatus, the carrier signal B is spread and the power density is reduced as shown in FIG. The carrier signal E has an increased power density in one of the four spreading codes. At this time, the power density of the carrier signal B is 6 dB lower than the carrier signal E, and the carrier signal E becomes dominant. Therefore, by detecting the reception level with the bandwidth W, the carrier signal E is selected, and the despreading process is performed on the carrier signal E by the second despreading units 2351 to 235o to receive from the local base station apparatus.

  Here, when the carrier signal E does not exist, even if the despreading process by the first despreading units 2311 to 231n is performed in the mobile station apparatus, as shown in FIG. No carrier signal is detected.

  In uplink communication from the mobile station apparatus to the local base station apparatus, as described above, the carrier signal defined by the W-CDMA communication system is also used in the local area communication. In public communication, as shown in FIG. 4 (d), an uplink carrier signal b that is paired with a downlink carrier signal B is selected. In private communication, any of the remaining a, c, d is selected. Select one of them. For this purpose, the mobile station apparatus stores a table in which the uplink carrier signals a, b, c, d and the downlink carrier signals A, B, C, D are associated with each other, and selects an uplink carrier based on this table. To do.

  For example, if the power density is increased in the carrier signal C as a result of the despreading process by the first despreading units 2311 to 231n in the mobile station device, the uplink carrier signal c is applied from the above table as the corresponding band, Select c as the carrier signal. Here, in order to avoid selecting the same band as the uplink carrier signal b for public wireless communication, the local base station apparatus must avoid using at least the carrier signal B, but selects from the remaining three spreading codes. There is no problem in using.

  Note that the mobile station apparatus shown in FIG. 2 shows a configuration including a plurality of despreading means and a plurality of level measuring means. This can also be realized by using the diffusing unit and the level measuring unit in a time-sharing manner.

  In the mobile station apparatus shown in FIG. 2, the configuration is shown in which the operation mode is switched between the private mode and the public mode. However, the reception system may be configured in a redundant configuration so that the private mode and the public mode are waited at the same time.

Next explained is the second embodiment of the invention.
FIG. 5 shows the configuration of a local base station apparatus of a mobile communication system according to the second embodiment of the present invention.

  The local base station apparatus includes an antenna 101, a duplexer 102, a control unit 100b, a radio frame configuration unit 110, a modulation unit 111, a spreading unit 112, a transmission RF unit 113, a reception RF unit 120, A despreading unit 130 and a demodulation unit 125 are provided.

  The control unit 100b controls each part of the local base station apparatus, calculates the number of bits of the radio frame, the spreading code, the spreading factor, and the amplification factor, and sends the information to each part that needs the information. By supplying each, the number of bits, spreading code, spreading factor, and amplification factor are controlled.

  As the spreading code, two types of spreading codes are designated for transmission, and two types of spreading codes are designated for reception. As the spreading factor, a spreading factor suitable for the amount of transmission information to be transmitted is selected.

  The radio frame configuration unit 110 generates a radio frame by inserting transmission information into a radio frame having the number of bits specified by the control unit 100b. Modulation section 111 performs primary modulation on the radio frame generated by radio frame configuration section 110 and outputs the modulation result to spreading section 112.

  The diffusion unit 112 plays a role of secondary modulation, and includes a first diffusion unit 112a and a second diffusion unit 112b. First, the first spreading unit 112a similarly performs spread modulation on the modulation result of the modulating unit 111 with one spreading code designated by the control unit 100b at a spreading factor designated by the control unit 100b.

  The first spreading unit 112a performs processing corresponding to channelization spreading and scramble spreading processing defined by the W-CDMA communication method used in the public mobile communication system, and is a spreading factor designated by the control unit 100b. Is the same as the spreading factor used in the public mobile communication system, and is one of a plurality of predetermined values, such as spreading factors 64, 128, and 256, for example. Note that the spreading factor is the ratio of the number of spreading code chips (spreading chip rate) to one bit (information bit rate) of a radio frame.

  Then, the signal spread-modulated by the first spreading unit 112a is similarly transmitted at the spreading factor designated by the control unit 100b using the other spreading code designated by the control unit 100b by the second spreading unit 112b. Perform spread modulation. This modulation result is output to transmission RF section 113.

  Here, the spreading factor assigned to the second spreading unit 112b by the control unit 100b is taken into consideration so that the frequency bandwidth is not excessively widened, and the public mobility is set to one of a plurality of predetermined values. The value is smaller than the spreading factor used in the communication system, for example, a spreading factor of 2 or 4. When the spreading factor is 2, two types of spreading codes are used, and when the spreading factor is 4, four types of spreading codes are used.

  The transmission RF unit 113 up-converts the modulation result of the second spreading unit 112b to the radio frequency of the band used in the public mobile communication system specified by the control unit 100b, and amplifies it with the amplification factor specified by the control unit 100b To do. The radio signal generated in this way is transmitted from the antenna 101 to the mobile station apparatus described later through the duplexer 102.

  On the other hand, a radio signal transmitted from the mobile station apparatus is received by the antenna 101 and input to the reception RF unit 120 through the duplexer 102. In the reception RF unit 120, the radio signal in the carrier frequency band specified by the control unit 100b is down-converted to an intermediate frequency, amplified, and then input to the despreading unit 130.

  The despreading unit 130 despreads the radio signal transmitted from the mobile station apparatus described above, and is configured as shown in FIG. 6, for example.

  The despreading unit 130 includes a first despreading unit 1311 to 131p, a first level measurement unit 1321 to 132p, a first level comparison unit 133, a first selection unit 134, and a second despreading unit 1351 to 135q. , Second level measuring units 1361 to 136q, a second level comparing unit 137, and a second selecting unit 138.

  The first despreading units 1311 to 131p perform a despreading process corresponding to the second spreading unit 240b of the mobile station apparatus described later, and use the spreading code specified by the control unit 100b, from the reception RF unit. Each received reception signal is despread.

  The first despreading units 1311 to 131p correspond to the diffusion rates used in the second diffusion unit 240b. That is, p corresponds to the number of types of diffusivities used in the second diffusing unit 240b. For example, if there are three diffusivities, p is 3. The signal obtained by the despreading process is input to the first selection unit 134 and the corresponding first level measurement units 1321 to 132p.

  The first level measuring units 1321 to 132p measure the levels of the signals input from the corresponding first despreading units 1311 to 131p, and output the measurement results to the first level comparing unit 133.

  The first level comparison unit 133 compares the measurement results input from the first level measurement units 1321 to 132p, detects the signal having the largest signal level, and notifies the first selection unit 134 of information for identifying the signal. To do.

  The first selection unit 134 selects a signal specified by the identification information from the level comparison unit 133 from among the signals input from the first despreading units 1311 to 131p, and uses the selected signal as the second despreading unit. It outputs to 1351-135q.

  The second despreading units 1351 to 135q correspond to the first spreading unit 240a of the mobile station apparatus to be described later, and are channelization despreading defined by the W-CDMA communication method used in the public mobile communication system. Further, a process corresponding to the scrambled despreading process is performed, and the signal output from the first selection unit 134 is despread using the spreading code specified by the control unit 100b.

  The second despreading units 1351 to 135q correspond to the spreading rates used in the first diffusion unit 240a. That is, q corresponds to the number of types of diffusivities used in the first diffusing unit 240a. For example, when there are three diffusivities, q is 3. The signal obtained by the despreading process is input to the second selection unit 138 and the corresponding second level measurement units 1361 to 136q.

  The second level measuring units 1361 to 136q measure the levels of the signals input from the corresponding second despreading units 1351 to 135q, and output the measurement results to the second level comparing unit 137.

  The second level comparison unit 137 compares the measurement results input from the second level measurement units 1361 to 136q, detects the signal having the highest signal level, and notifies the second selection unit 138 of information for identifying the signal. To do.

  The second selection unit 138 selects a signal specified by the identification information from the level comparison unit 133 among the signals input from the first despreading units 1311 to 131p, and selects the selected signal from the demodulation unit 221 at the subsequent stage. Output to.

  Demodulation section 221 performs data demodulation corresponding to primary modulation of the mobile station apparatus to be described later, acquires reception information, and outputs it to a subsequent data processing section (not shown).

Next, with reference to FIG. 7, the structure of the mobile station apparatus of the mobile communication system concerning the 2nd Embodiment of this invention is demonstrated.
The mobile station apparatus includes an antenna 201, a duplexer 202, a control unit 200b, a radio frame configuration unit 210, a modulation unit 211, a spreading unit 240, a transmission RF unit 213, a reception RF unit 220, and a reverse A diffusion unit 230 and a demodulation unit 221 are provided.

  The control unit 200b controls the respective units of the mobile station apparatus in an integrated manner, and according to mode settings set by the user through a key operation unit (not shown), the number of bits of the radio frame, the spreading code, and the spreading factor The number of bits, the spreading code, the spreading factor, and the amplification factor are controlled by calculating the amplification factor and supplying the information to each unit that requires the information.

  As the spreading code, two types of spreading codes are designated for transmission, and two types of spreading codes are designated for reception. As the spreading factor, a spreading factor suitable for the amount of transmission information to be transmitted is selected.

  Radio frame configuration section 210 generates a radio frame by inserting transmission information into a radio frame having the number of bits specified by control section 200b. Modulation section 211 performs primary modulation on the radio frame generated by radio frame configuration section 210 and outputs the modulation result to spreading section 240.

  The spreading unit 240 plays a role of secondary modulation, and includes a first spreading unit 240a, a switching unit 240c, and a second spreading unit 240b. Here, the spreading code designated by the control unit 200b is used properly depending on whether it is for the local base station apparatus or the public base station apparatus, depending on the mode setting.

  First, the first spreading unit 240a spread-modulates the modulation result of the modulating unit 211 with the spreading factor designated by the control unit 200b in the same manner using one spreading code designated by the control unit 200b.

  The first spreading unit 240a performs processing corresponding to channelization spreading and scramble spreading processing defined by the W-CDMA communication method used in the public mobile communication system, and is a spreading factor designated by the control unit 200b. Is the same as the spreading factor used in the public mobile communication system, and is one of a plurality of predetermined values, such as spreading factors 64, 128, and 256, for example. Note that the spreading factor is the ratio of the number of spreading code chips (spreading chip rate) to one bit (information bit rate) of a radio frame.

  The signal spread-modulated by the first spreading unit 240a is input to the switching unit 240c. The switching unit 240c outputs the spread-modulated signal to the second spreading unit 240b when the local mode is designated from the control unit 200b, while the public mode is designated from the control unit 200b. The spread-modulated signal is output to the transmission RF section 213 at the subsequent stage. That is, when the public mode is designated, the second diffusion unit 240b is bypassed.

  Similarly, the second spreading unit 240b uses the other spreading code designated by the control unit 100b to the signal spread-modulated by the first spreading unit 240a, and similarly, the spreading factor designated by the control unit 100b. To spread and modulate. This modulation result is output to transmission RF section 213.

  Here, the spreading factor assigned to the second spreading unit 240b by the control unit 200b is taken into consideration so that the frequency bandwidth is not excessively widened, and the public mobility is set to one of a plurality of predetermined values. The value is smaller than the spreading factor used in the communication system, for example, a spreading factor of 2 or 4. When the spreading factor is 2, two types of spreading codes are used, and when the spreading factor is 4, four types of spreading codes are used.

  The transmission RF unit 213 up-converts the modulation result of the spreading unit 212 to a radio frequency of a band used in the public mobile communication system specified by the control unit 200b, and amplifies it with the amplification factor specified by the control unit 200b. The wireless signal generated in this way is transmitted from the antenna 201 through the duplexer 202 to the above-described local base station apparatus and public base station apparatus used in the public mobile communication system.

  On the other hand, a radio signal transmitted from the above-described local base station apparatus or the public base station apparatus is received by the antenna 201 and input to the reception RF unit 120 through the duplexer 202. In the reception RF unit 120, the radio signal in the carrier frequency band specified by the control unit 200b is down-converted to an intermediate frequency, amplified, and then input to the despreading unit 230.

  The despreading unit 230 selects one of the radio signal transmitted from the above-described local base station device and the radio signal transmitted from the public base station device according to the mode setting designated by the control unit 200b. It selectively despreads and is configured as shown in FIG. 3, for example.

  The despreading unit 230 includes a switching unit 2300, first despreading units 2311 to 231n, first level measurement units 2321 to 232n, a first level comparison unit 233, a first selection unit 234, and a second despreading unit. Units 2351 to 235o, second level measurement units 2361 to 236o, a second level comparison unit 237, and a second selection unit 238.

  When the reception signal output from the reception RF unit 220 is input to the switching unit 2300 and the local mode is designated from the control unit 200b, the switching unit 2300 outputs the reception signal to the first despreading units 2311 to 231n. When the public mode is designated from the control unit 200b, the received signal is output to the second despreading units 2351 to 235o in the subsequent stage.

  That is, when the public mode is designated, the first despreading units 2311 to 231n, the first level measurement units 2321 to 232n, the first level comparison unit 233, and the first selection unit 234 are bypassed.

  The first despreading units 2311 to 231n perform the despreading process corresponding to the second spreading unit 112b of the local base station apparatus described above, and use the spreading code specified by the control unit 200b to switch the switching unit 2300. The received signal output from is despreaded.

  The first despreading units 2311 to 231n correspond to the spreading rates used in the second diffusion unit 112b. That is, n corresponds to the number of types of diffusivities used in the second diffusing unit 112b. For example, if there are three diffusivities, n is 3. A signal obtained by the despreading process is input to the first selection unit 234 and the corresponding first level measurement units 2321 to 232n.

  The first level measurement units 2321 to 232n measure the levels of the signals input from the corresponding first despreading units 2311 to 231n, and output the measurement results to the first level comparison unit 233.

  The first level comparison unit 233 compares the measurement results input from the first level measurement units 2321 to 232n, detects the signal having the highest signal level, and notifies the first selection unit 234 of information for identifying the signal. To do.

  The first selection unit 234 selects a signal specified by the identification information from the level comparison unit 233 from among the signals input from the first despreading units 2311 to 231n, and selects the selected signal as the second despreading unit. 2351 to 235o.

  The second despreading units 2351 to 235o correspond to the first spreading unit 112a of the private base station apparatus described above, and are channelization reverses defined by the W-CDMA communication method used in the public mobile communication system. A process corresponding to the spreading and scrambled despreading process is performed, and the signal output from the first selection unit 234 or the switching unit 2300 is reversed using the spreading code specified by the control unit 200b. Diffusion processing.

  The second despreading units 2351 to 235o correspond to the spreading factors used in the first diffusion unit 112a. That is, o corresponds to the number of types of spreading factors used in the first spreading unit 112a. For example, when there are three spreading factors, o is 3. The signal obtained by the despreading process is input to the second selection unit 238 and the corresponding second level measurement units 2361 to 236o.

  The second level measurement units 2361 to 236o measure the levels of the signals input from the corresponding second despreading units 2351 to 235o, and output the measurement results to the second level comparison unit 237.

  The second level comparison unit 237 compares the measurement results input from the second level measurement units 2361 to 236o, detects the signal having the highest signal level, and notifies the second selection unit 238 of information for identifying the signal. To do.

  The second selection unit 238 selects a signal specified by the identification information from the level comparison unit 233 among the signals input from the first despreading units 2311 to 231n, and selects the selected signal from the demodulation unit 221 at the subsequent stage. Output to.

  The demodulator 221 performs data demodulation corresponding to the primary modulation of the local base station apparatus and the public base station apparatus described above to acquire reception information, and outputs the received information to a subsequent data processing unit (not shown).

  As described above, in the mobile communication system configured as described above, when a mobile station apparatus communicates with a public base station apparatus, a mode setting using the public mode is made in advance by the user, and the switching unit 2300 is switched and controlled. As a despreading process corresponding to a radio signal from a public base station apparatus using a despreading unit 2351 to 235o, a second level measurement unit 2361 to 236o, a second level comparison unit 237, and a second selection unit 238, public mobile communication Channelization despreading and scrambled despreading processing specified by the W-CDMA communication system used in the system is performed for reception.

  For transmission, the mobile station apparatus switches the switching unit 240c in the spreading unit 240 according to the setting of the premises mode, and uses the first spreading unit 240a to use the W-CDMA communication system used in the public mobile communication system. The channelization spread and scramble spread processing defined in the above is performed, and a radio signal is generated with the transmission target as a public base station apparatus.

  That is, the mobile station apparatus performs switching setting of the switching unit 240c and the switching unit 2300 according to the setting of the public mode, and selects a circuit necessary for communication with the public base station apparatus to transmit and receive radio signals. The Thereby, the mobile station apparatus can perform public wireless communication through the public base station apparatus as in the conventional case.

  On the other hand, when the mobile station apparatus communicates with the local base station apparatus, the local base station apparatus uses the first spreading unit 112a to perform channelization spreading defined by the W-CDMA communication method used in the public mobile communication system. In addition to this, the scramble spreading process is performed, and in addition to this, the second spreading unit 112b further performs a spreading process to perform wireless transmission.

  On the other hand, in the mobile station apparatus, mode setting using the premise mode is made in advance by the user, and the switching unit 2300 is switched and controlled, and the first despreading units 2311 to 231n, the first level measuring units 2321 to 232n, and the first level are controlled. The comparison unit 233 and the first selection unit 234 are used to perform the despreading process corresponding to the second spreading unit 112b of the local base station apparatus, and then the second despreading units 2351 to 235o and the second level measuring unit 2361 ˜236o, the second level comparison unit 237, and the second selection unit 238 are used to perform reception by performing a despreading process corresponding to the first spreading unit 112a of the local base station apparatus.

  For transmission, the mobile station apparatus switches the switching unit 240c in the spreading unit 240 according to the setting of the premises mode, first performs spreading processing using the first spreading unit 240a, and further performs the second spreading unit 240b. Is used to generate a radio signal with the transmission target as a local base station device.

  On the other hand, the local base station apparatus uses the first despreading units 1311 to 131p, the first level measurement units 1321 to 132p, the first level comparison unit 133, and the first selection unit 134 in the despreading unit 130. Then, the despreading process corresponding to the second spreading unit 240b of the mobile station apparatus is performed, and then the second despreading units 1351 to 135q, the second level measuring units 1361 to 136q, the second level comparing unit 137, and the second selection Using the unit 138, despreading processing corresponding to the first spreading unit 240a of the mobile station apparatus is performed.

  That is, each of the mobile station apparatus and the local base station apparatus generates and transmits a radio signal targeting each other by two spreading processes, and performs two despreading processes corresponding to the two spreading processes. A radio signal is received. Thereby, the mobile station apparatus can perform private wireless communication through the carrier frequency band used by the public base station apparatus.

  FIG. 8 shows an image of the carrier signal spectrum transmitted from the local base station device (FIG. 8A) and an image diagram of the carrier signal spectrum obtained by the despreading process of the mobile station device (FIG. 8B). . In this figure, an example is shown in which four waves of bandwidth W are used in public wireless communication, and spread processing is further quadrupled in private wireless communication.

  FIG. 8A shows a situation in which the carrier signal B is used among the four waves of the carrier signals A to D by public wireless communication, and the carrier signal E is used by the local base station apparatus. . Since the carrier signal E is spread four times with respect to the carrier signal B, the power density is 6 dB lower.

  For this reason, when the reception level is detected with the bandwidth W in the mobile station apparatus, the carrier signal B is dominant, and this carrier signal B is selected and subjected to W-CDMA despreading processing and demodulation processing.

  On the other hand, when the first despreading units 2311 to 231n perform the despreading process in the mobile station apparatus, the carrier signal B is spread and the power density is lowered as shown in FIG. The carrier signal E has an increased power density in one of the four spreading codes. At this time, the power density of the carrier signal B is 6 dB lower than the carrier signal E, and the carrier signal E becomes dominant. Therefore, by detecting the reception level with the bandwidth W, the carrier signal E is selected, and the despreading process is performed on the carrier signal E by the second despreading units 2351 to 235o to receive from the local base station apparatus.

  FIG. 8 shows an image of the carrier signal spectrum transmitted from the mobile station apparatus (FIG. 8C) and an image diagram of the carrier signal spectrum obtained by the despreading process of the local base station apparatus (FIG. 8D). Show.

  FIG. 8C shows a situation where the carrier signal b is used among the four waves of the carrier signals a to d by public wireless communication, and the carrier signal e is used by the mobile station apparatus. Since the carrier signal e is spread four times with respect to the carrier signal b, the power density is 6 dB lower.

  For this reason, when the reception level is detected with the bandwidth W in the local base station apparatus, the carrier signal b is dominant, and this carrier signal b is selected and subjected to W-CDMA despreading processing and demodulation processing.

  On the other hand, when the first despreading units 1311 to 131p perform the despreading process in the local base station, the carrier signal b is spread and the power density is lowered as shown in FIG. The carrier signal e increases in power density in one of the four spreading codes. At this time, the power density of the carrier signal b is 6 dB lower than the carrier signal e, and the carrier signal e becomes dominant. Therefore, by detecting the reception level with the bandwidth W, the carrier signal e is selected, and the despreading process by the second despreading units 1351 to 135q is performed on the carrier signal e, and reception from the local base station apparatus is performed.

  Therefore, according to the mobile communication system configured as described above, since carrier signals spread over a wide range are used for both downlink communication and uplink communication, any one of the four carrier signals can be transmitted without being aware of the carrier signals used in public wireless communication. Can also be used.

  In addition, although the local base station apparatus shown in FIG. 5 and the mobile station apparatus shown in FIG. 7 show a configuration including a plurality of despreading means and a plurality of level measuring means, the despreading means and the level measuring means are It can be realized by using each one despreading means and level measuring means in a time division manner.

  In the mobile station apparatus shown in FIG. 7, the configuration is shown in which the operation mode is switched between the private mode and the public mode. However, the reception system may be configured in a redundant configuration so that the private mode and the public mode are waited at the same time.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. Further, for example, a configuration in which some components are deleted from all the components shown in the embodiment is also conceivable. Furthermore, you may combine suitably the component described in different embodiment.

  For example, as the spreading process, the channelization and scramble process defined in the W-CDMA communication system has been described as an example, but other CDMA multiplexing systems defined in the CDMA-2000 communication system, etc. are applied. You can also.

Further, the diffusion process is described as being performed in two stages of the first diffusion process and the second diffusion process. However, it is not necessary to divide the function into two functional means. There is no problem even if the method is divided. The same applies to the configurations of the first despreading process and the second despreading process.
In addition, it goes without saying that the present invention can be similarly implemented even if various modifications are made without departing from the gist of the present invention.

The circuit block diagram which shows the structure of 1st Embodiment of the local base station apparatus of the mobile communication system concerning this invention. The circuit block diagram which shows the structure of 1st Embodiment of the mobile station apparatus of the mobile communication system concerning this invention. The circuit block diagram which shows the structure of the de-spreading part of the mobile station apparatus shown in FIG. The figure which shows the carrier signal spectrum each handled by the local base station apparatus shown in FIG. 1, and the mobile station apparatus shown in FIG. The circuit block diagram which shows the structure of 2nd Embodiment of the local base station apparatus of the mobile communication system concerning this invention. The circuit block diagram which shows the structure of the de-spreading part of the local base station apparatus shown in FIG. The circuit block diagram which shows the structure of 2nd Embodiment of the mobile station apparatus of the mobile communication system concerning this invention. The figure which shows the carrier signal spectrum each handled by the local base station apparatus shown in FIG. 5, and the mobile station apparatus shown in FIG.

Explanation of symbols

  100a, 100b ... control unit, 101 ... antenna, 102 ... duplexer, 110 ... radio frame configuration unit, 111 ... modulation unit, 112 ... spreading unit, 112a ... first spreading unit, 112b ... second spreading unit, 113 ... transmission RF unit, 120 ... reception RF unit, 1211-121m ... despreading unit, 1221-122m ... level measurement unit, 123 ... level comparison unit, 124 ... selection unit, 125 ... demodulation unit, 130 ... despreading unit, 1311-131p ... 1st despreading part, 1321-132p ... 1st level measurement part, 133 ... 1st level comparison part, 134 ... 1st selection part, 1351-135q ... 2nd despreading part, 1361-136q ... 2nd level measurement Part, 137 ... second level comparison part, 138 ... second selection part, 200a, 200b ... control part, 201 ... antenna, 202 ... duplexer, 210 ... radio frame configuration part 211: Modulation unit, 212: Spreading unit, 213: Transmission RF unit, 220 ... Reception RF unit, 221 ... Demodulation unit, 230 ... Despreading unit, 2300 ... Switching unit, 2311-231n ... First despreading unit, 2321- 232n ... first level measuring unit, 233 ... first level comparing unit, 234 ... first selecting unit, 2351-235o ... second despreading unit, 2361-236o ... second level measuring unit, 237 ... second level comparing unit 238, second selection unit, 240, diffusion unit, 240a, first diffusion unit, 240b, second diffusion unit, 240c, switching unit.

Claims (15)

In a radio base station apparatus that is used in a mobile communication system adopting a CDMA system and wirelessly communicates with a mobile radio terminal apparatus,
First spreading means for spreading and modulating transmission information using a first spreading code;
Second spreading means for spreading and modulating the modulation result obtained from the first spreading means using a second spreading code;
A radio base station apparatus comprising: a transmission means for wirelessly transmitting a modulation result obtained from the second spreading means to the mobile radio terminal apparatus. Furthermore, receiving means for receiving a radio signal from the mobile radio terminal device and frequency-converting the radio signal;
The radio base station apparatus according to claim 1, further comprising: a despreading unit that despreads the output signal of the receiving unit using a third spreading code. Furthermore, receiving means for receiving a radio signal from the mobile radio terminal device and frequency-converting the radio signal;
First despreading means for despreading the output signal of the receiving means using a third spreading code;
The radio base station apparatus according to claim 1, further comprising: a second despreading unit that despreads the output signal of the first despreading unit using a fourth spreading code. In a mobile radio terminal device that is used in a mobile communication system employing a CDMA system and communicates with a radio base station device connected to a network,
Receiving means for receiving a radio signal from the radio base station apparatus and converting the frequency thereof;
First despreading means for despreading the output signal of the receiving means using a first spreading code;
A mobile radio terminal apparatus comprising: a second despreading unit that despreads the output signal of the first despreading unit using a second spreading code. And spreading means for spreading and modulating transmission information using a third spreading code;
A mobile radio terminal apparatus comprising: a transmission means for wirelessly transmitting a modulation result obtained from the spreading means to the radio base station apparatus. A first spreading means for spreading and modulating transmission information using a third spreading code;
Second spreading means for spreading and modulating the modulation result obtained from the first spreading means using a fourth spreading code;
A mobile radio terminal apparatus comprising: a transmission means for wirelessly transmitting a modulation result obtained from the second spreading means to the radio base station apparatus. In a mobile communication system in which a mobile radio terminal apparatus and a radio base station apparatus perform radio communication by CDMA,
The wireless base station device
First spreading means for spreading and modulating transmission information using a first spreading code;
Second spreading means for spreading and modulating the modulation result obtained from the first spreading means using a second spreading code;
Transmission means for wirelessly transmitting the modulation result obtained from the second spreading means to the mobile radio terminal device;
The mobile radio terminal device
Receiving means for receiving a radio signal from the radio base station apparatus and converting the frequency thereof;
First despreading means for despreading the output signal of the receiving means using the second spreading code;
2. A mobile communication system comprising: a second despreading unit that despreads the output signal of the first despreading unit using the first spreading code. Furthermore, the mobile radio terminal device
Spreading means for spreading and modulating transmission information using a third spreading code;
Transmission means for wirelessly transmitting a modulation result obtained from the spreading means to the radio base station apparatus,
The wireless base station device
Receiving means for receiving a radio signal from the mobile radio terminal device and converting the frequency thereof;
8. The mobile communication system according to claim 7, further comprising despreading means for despreading the output signal of the receiving means using the third spreading code. Furthermore, the mobile radio terminal device
First spreading means for spreading and modulating transmission information using a third spreading code;
Second spreading means for spreading and modulating the modulation result obtained from the first spreading means using a fourth spreading code;
Transmission means for wirelessly transmitting the modulation result obtained from the second spreading means to the radio base station apparatus;
The wireless base station device
Receiving means for receiving a radio signal from the mobile radio terminal device and converting the frequency thereof;
First despreading means for despreading the output signal of the receiving means using the fourth spreading code;
The mobile communication system according to claim 7, further comprising second despreading means for despreading the output signal of the first despreading means using the third spreading code. A public base station device connected to a public network, and a mobile radio terminal device capable of wireless communication with a local base station device connected to the network,
Receiving means for receiving a radio signal from the public base station apparatus or the local base station apparatus and frequency-converting the radio signal;
When receiving a radio signal from the public base station apparatus, despreading the output signal of the receiving means using a first spreading code, while receiving a radio signal from the local base station apparatus Comprises a despreading means for despreading the output signal of the receiving means using a first spreading code and further despreading using a second spreading code. Furthermore, spreading means for spreading and modulating transmission information using a third spreading code, and
A mobile radio terminal apparatus comprising: a transmission means for wirelessly transmitting a modulation result obtained from the spreading means to the public base station apparatus or the private base station apparatus. Further, when a radio signal is transmitted to the public base station apparatus, transmission information is spread-modulated and output using a third spreading code, while on the other hand, when a radio signal is transmitted to the local base station apparatus Spreading means for spreading and modulating the transmission information using the third spreading code and further spreading and modulating the transmission information using the fourth spreading code;
A mobile radio terminal apparatus comprising: a transmission means for wirelessly transmitting a modulation result output from the spreading means to the public base station apparatus or the private base station apparatus. In a mobile communication system in which a mobile radio terminal apparatus and a radio base station apparatus perform radio communication by CDMA,
The wireless base station device
First spreading means for spreading and modulating transmission information using a first spreading code;
Second spreading means for spreading and modulating the modulation result obtained from the first spreading means using a second spreading code;
Transmission means for wirelessly transmitting the modulation result obtained from the second spreading means to the mobile radio terminal device,
The mobile radio terminal device
Receiving means for receiving a radio signal from a public base station apparatus connected to a public network or the radio base station apparatus, and converting the frequency thereof;
When receiving a radio signal from the public base station apparatus, despreading the output signal of the receiving means using a first spreading code, while receiving a radio signal from the local base station apparatus Comprises a despreading unit that despreads the output signal of the receiving unit using a second spreading code and despreads using the first spreading code. Furthermore, the mobile radio terminal device
Spreading means for spreading and transmitting transmission information using a third spreading code; and
Transmission means for wirelessly transmitting the modulation result obtained from the spreading means to the public base station apparatus or the radio base station apparatus,
The wireless base station device
Receiving means for receiving a radio signal from the mobile radio terminal device and converting the frequency thereof;
14. The mobile communication system according to claim 13, further comprising despreading means for despreading the output signal of the receiving means using the third spreading code. Furthermore, the mobile radio terminal device
When transmitting a radio signal to the public base station apparatus, the transmission information is spread-modulated using a third spreading code and output. On the other hand, when transmitting a radio signal to the radio base station apparatus, the transmission information is transmitted. Spreading means for spreading and modulating information using a third spreading code, and further spreading and modulating information using a fourth spreading code;
A transmission unit that wirelessly transmits the modulation result output by the spreading unit to the radio base station device;
The wireless base station device
Receiving means for receiving a radio signal from the mobile radio terminal device and converting the frequency thereof;
First despreading means for despreading the output signal of the receiving means using the fourth spreading code;
14. The mobile communication system according to claim 13, further comprising second despreading means for despreading the output signal of the first despreading means using the third spreading code.

Images