JPH0670361A - Radio base station equipment for mobile communication system - Google Patents

Abstract

PURPOSE:To provide the radio base station of the mobile communication system in which monitor/control of a radio signal sent from an antenna section is implemented by a radio transmission reception section connected to the antenna section through an optical fiber transmission line. CONSTITUTION:Part of signal 308 sent to a mobile terminal equipment 400 is synthesized with a reception radio signal 312 by an antenna section 300 and the synthesis signal is converted into an optical signal 202. The optical signal 202 is sent to a radio transmission reception section 100 through an optical fiber transmission line 206, and the radio transmission section 100 monitors a transmission radio signal 308 included in the optical signal 202. That is, the radio transmission reception section 100 detects the intensity or frequency of the transmission radio signal 308 to apply negative feedback to the intensity or frequency of the radio signal 104 sent through the optical fiber transmission line 200 to the antenna section 300, and the intensity and frequency of the transmission radio signal 308 is controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio base station apparatus of a mobile communication system in which a radio transmitter / receiver section and an antenna section are separated, and more particularly to a radio base station apparatus having an improved supervisory control method for the antenna section.

[0002]

2. Description of the Related Art In a mobile communication system such as a car telephone system, a service area is divided into a plurality of zones called cells, and a radio base station for exchanging radio signals with mobile stations in the zone is arranged in each zone. ing. The radio base station in the car phone system is described in the literature (published by The Institute of Electronics and Communication Engineers, Car Phone, Moruji Kuwahara, No.
As described on page 52), it is composed of an antenna unit, a transmitting / receiving device for communication and control, a base station control device, and the like.

In the mobile communication system described above, a micro cell system is currently attracting attention, in which a service area is divided into small cells having a diameter of several hundred meters or less to improve frequency utilization efficiency. When this microcell system is realized, the wireless base station will be installed on a streetlight or a utility pole. However, current wireless base stations include transmitters / receivers and base station controllers, and installing them on streetlights or power poles is extremely difficult in terms of size, weight, power consumption, reliability, etc. There was a problem that it was difficult. As a method for solving this problem, a method of separating a wireless base station into a wireless transmission / reception unit including a wireless transmission / reception device and a base station control device and an antenna unit and connecting them with an optical fiber transmission line is under study. (For example, a paper of the Institute of Electronics, Information and Communication Engineers, a study group of wireless communication systems by Shibuya et al., "Radio Signal Collection and Delivery Method for Optical Microcell Mobile Communication" RCS90-12). According to this method, the radio signal transmitted / received by the antenna section is transmitted as it is to the radio transmission / reception section through the optical fiber transmission line, where modulation / demodulation and radio line control are performed. Since the antenna unit installed in each cell only needs to convert an optical signal and an electric signal and amplify a radio signal, the antenna unit can be dramatically reduced in size and weight and highly reliable.

[0004]

The radio base station connecting the radio transmission / reception section and the antenna section by the above-mentioned optical fiber transmission line needs a function of monitoring and controlling whether or not the radio signal is transmitted from the antenna in a good state. Is. However, it is necessary to avoid increasing the size of the antenna part due to this monitoring control function.

Further, in the future microcell mobile communication system, it is considered that the antenna section of the radio base station is installed in each microcell, and the radio transmitting / receiving section is collectively installed in the center station. In such a configuration,
It is desirable that the center station collectively monitor the transmission status of wireless signals.

In the microcell mobile communication system,
The transmission output from the antenna unit is frequently changed with the increase or decrease of communication traffic or the change of cell arrangement or size. At this time, if the transmission output can be changed by the wireless transceivers collectively installed in the center station, it is not necessary to adjust the level in the antenna unit installed in each cell.

Further, in a radio base station that connects an antenna section and a radio transmission / reception section by an optical fiber transmission line, it has been considered to use a pair of optical fiber transmission lines by using a frequency conversion technique. There is. For example, even if the radio signal frequency transmitted from each antenna unit is in the same 800 MHz band, the radio signal is transmitted at a different frequency for each antenna unit in the optical fiber, and each antenna unit allocates the frequency Of the wireless signal is extracted by a filter, frequency-converted to the 800 MHz band and transmitted. Regarding the application of frequency conversion to a mobile communication system using such an optical fiber, details are described in, for example, the patent specification of Japanese Patent Application No. 3-277649 "Micro base station, center base station and mobile communication device". Has been.

In the above mobile communication system, it is necessary to control the frequency of the radio signal extremely accurately in order to prevent radio wave interference and the like. Therefore, in order to increase the frequency stability of the transmission radio signal when using the above frequency conversion technique, it is necessary to make the frequency stability of the local oscillator used in the frequency conversion circuit very high. Further, in the microcell mobile communication system, since the antenna unit is installed outdoors, a local oscillator that is stable against large temperature changes is required. However, such a local oscillator having high frequency stability has a complicated structure, and is large and expensive. Therefore, it is desirable to install a small and low-priced local oscillator in each antenna section and correct the frequency fluctuation of the transmission radio signal due to the frequency deviation of the local oscillator at the center station.

Therefore, a first object of the present invention is mobile communication in which the strength and frequency of a radio signal transmitted from an antenna unit can be monitored and controlled by a radio transmitter / receiver unit connected to the antenna unit by an optical fiber transmission line. It is to provide a wireless base station device of the system.

A second object of the present invention is to provide a radio base station apparatus for the mobile communication system, which can improve the reliability of an antenna section which is often installed outdoors and is troublesome to maintain. is there.

[0011]

According to a first aspect of the present invention, there is provided a radio base station apparatus for a mobile communication system, wherein an antenna section and a radio transmission / reception section are separated from each other, and the antenna section and the radio transmission / reception section are provided by an optical fiber transmission line. In a wireless base station device in which the transmission of a wireless signal between is performed, a part of the transmission wireless signal transmitted from the antenna unit to the mobile station is transmitted to the wireless transmission / reception unit by the optical fiber transmission path,
The wireless transmission / reception unit monitors the transmitted wireless signal.

Further, in the radio base station apparatus of the mobile communication system of the second invention, the antenna section and the radio transmission / reception section are separated, and the radio signal between the antenna section and the radio transmission / reception section is provided by the optical fiber transmission line. In the wireless base station device in which the transmission is performed, a part of the transmission wireless signal transmitted from the antenna unit to the mobile station is transmitted to the wireless transmission / reception unit via the optical fiber transmission line, and the wireless transmission / reception unit described above It is characterized in that the strength of the transmission wireless signal is detected and the strength of the wireless signal transmitted from the wireless transmission / reception unit to the antenna unit is controlled according to the detected strength.

In the radio base station device of the mobile communication system according to the third aspect of the invention, the antenna section and the radio transmission / reception section are separated, and the radio signal between the antenna section and the radio transmission / reception section is transmitted by an optical fiber transmission line. The radio signal transmitted and transmitted from the radio transmission / reception unit to the antenna unit via the optical fiber transmission line is frequency-converted by the frequency conversion circuit in the antenna unit and then transmitted to the mobile station. In the radio base station device, a part of the output of the local oscillator that supplies the local oscillation signal to the frequency conversion circuit is transmitted to the radio transmission / reception unit via the optical fiber transmission line, and the frequency of the local oscillator output in the radio transmission / reception unit. To detect the frequency and control the frequency of the radio signal transmitted from the radio transmission / reception unit to the antenna unit accordingly. And butterflies.

In the base station apparatus of the mobile communication system according to the fourth aspect of the present invention, the antenna section and the radio transmission / reception section are separated, and a radio signal between the antenna section and the radio transmission / reception section is transmitted by an optical fiber transmission line. A radio signal transmitted and transmitted from the radio transmission / reception unit to the antenna unit by the optical fiber transmission line is frequency-converted into a transmission radio signal by the first frequency conversion circuit in the antenna unit, and then the mobile station. In the wireless base station device that is transmitted toward the wireless base station device, a part of the transmission wireless signal transmitted from the antenna unit is frequency-converted into a wireless signal again by the second frequency converter to which the local oscillation signal is supplied. A radio signal is transmitted to the radio transmission / reception unit via the optical fiber transmission line, and the frequency of the transmission radio signal is detected in the radio transmission / reception unit. , And controlling the frequency of the radio signal transmitted from the wireless transceiver to the antenna unit accordingly.

[0015]

In the first aspect of the invention, a part of the transmission radio signal transmitted from the antenna section of the radio base station apparatus to the mobile station is transmitted to the radio transmission / reception section through the optical fiber transmission line. Therefore, since the state of the transmission radio signal can be monitored by the wireless transmission / reception unit, the antenna unit does not require a detector for monitoring, and the antenna unit installed in each zone can be prevented from increasing in size. .

According to the second aspect of the invention, the radio transmitter / receiver of the radio base station device detects the strength of the transmission radio signal transmitted from the antenna section, and in accordance with this, the strength of the radio signal transmitted to the antenna section. To control. This makes it possible to keep the output intensity of the transmission wireless signal from the antenna unit constant. Therefore, since the intensity detector and the intensity adjusting circuit are not required in the antenna section, the configuration of the antenna section is simplified. Further, by changing the strength of the radio signal transmitted to the antenna section by the radio transmission / reception section, the strength of the transmission radio signal transmitted from the antenna section can be changed. Therefore, even if it is necessary to change the intensity of the transmission wireless signal, it is not necessary to adjust the level of the transmission wireless signal in the antenna section installed in each zone.

Further, in the third and fourth aspects of the invention, in the radio base station apparatus to which the frequency conversion technique is applied, one of the local oscillator output and the transmission radio signal frequency-converted by the local oscillator is transmitted from the antenna section. It is transmitted to the wireless transceiver. The wireless transmission / reception unit detects the frequency of the local oscillator output and the transmission wireless signal, and controls the frequency of the wireless signal transmitted to the antenna unit accordingly. Therefore, even when the oscillation frequency of the local oscillator of the antenna unit fluctuates, the frequency of the transmission radio signal can be kept constant.

[0018]

The present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of the first embodiment of the present invention. The mobile communication system to which the base station apparatus of this embodiment is applied is a radio transmitting / receiving unit 100 and an optical fiber transmission line 20.
0,202 and the antenna unit 300, the wireless base station device, the mobile terminal 400, and the car telephone exchange 50.
Contains 0 and. The mobile terminal 400 and the car switching center 500 are similar to the devices used in a general mobile communication system, and their configurations are widely known by those skilled in the art, and therefore will not be described in detail here.

A radio signal 10 output from the modulator 102 of the radio transmitter / receiver 100 and containing a telephone signal (call signal) 502.
4 is converted into an optical signal 204 by an electric / optical conversion circuit 106 composed of a semiconductor laser and a driver circuit thereof, and the antenna section 300 is transmitted via a fiber transmission path 200.
Be transmitted to. In the antenna unit 300, the optical signal 204 is converted into a radio signal again by the optical / electrical conversion circuit 302 including a photodiode and a front end circuit, amplified by the high output amplifier 304, and passed through the demultiplexer 320. Most of this amplified signal is the transmitted radio signal 3
It is transmitted from the antenna 310 to the mobile terminal 400 as 06.

On the other hand, the received radio signal 312 transmitted from the mobile terminal 400 and received by the antenna 314 passes through the band pass filter 316, is further amplified by the low noise amplifier 318, and is then demultiplexed by the demultiplexer 320. A part of the transmitted radio signal 308 is multiplexed by the multiplexer 322. The combined radio signal is converted into an optical signal 206 by the electrical / optical conversion circuit 324, and is transmitted to the radio transmission / reception unit 100 by the optical fiber transmission line 202.
The optical signal 206 sent from the antenna unit 300 to the wireless transmission / reception unit 100 is converted again by the optical / electrical conversion circuit 110 into a transmission wireless signal 114 (same as the transmission wireless signal 308) and a reception wireless signal 112, and both are transmitted. Duplexer 116
Separated by. The received wireless signal 112 is demodulated by the demodulator 118 into a telephone signal (call signal) 504. On the other hand, the transmission radio signal 114 is input to the spectrum analyzer 120, and the strength, frequency, distortion of the signal, the presence or absence of unnecessary radiation, etc. are monitored.

FIG. 2 is a block diagram of the second embodiment of the present invention. The base station device of this mobile communication system controls the intensity of the transmission radio signal 306 in addition to monitoring the transmission radio signal 308. In the antenna unit 300A of the base station device,
A pilot signal 332 is output from the oscillator 330, and this signal 332 is combined with the transmission radio signal 308 supplied from the demultiplexer 320 and the reception radio signal 312 that has passed through the amplifier 318 and the limiter circuit 334 by the multiplexer 336. , And inputs the combined signal to the electric / optical conversion circuit 324.
In this embodiment, the strength of the pilot signal 332 is 0.1 m.
It was W. The branching ratio of the signal to the antenna 310 and the multiplexer 336 by the demultiplexer 320 is 1: 100. For example, when the intensity of the transmission radio signal 306 output from the antenna 310 is 10 mW, the signal is supplied to the demultiplexer 332. The intensity of the transmitted wireless signal 308 is 0.1 mW. Note that the reception wireless signal 312 is amplitude-limited by the limiter circuit 334 before being combined with the pilot signal 332 and the transmission wireless signal 308 in order to protect the electrical / optical conversion circuit 324. In this embodiment, the limiter circuit 334 limits the intensity of the received radio signal 312 input to the electrical / optical conversion circuit 324 to 1 mW or less regardless of the intensity of the reception at the antenna 314.

The radio transmission / reception section 100A of the base station apparatus receives the reception radio signal 11 output from the optical / electrical conversion circuit 110.
2, the pilot signal 122 (same as the pilot signal 332) and the transmission radio signal 114 are passed through the band pass filter 13
Separated by 0, 132, and 134, the pilot signal 122 and the transmission radio signal 114 are supplied to the transmission strength control circuit 136. The transmission strength control circuit 136 controls the strength of the radio signal 104 based on the pilot signal 122 and the transmission radio signal 114, and the antenna unit 300.
The strength of the transmission wireless signal 306 transmitted from A is stabilized to a predetermined value.

FIG. 3 is a block diagram of the transmission strength control circuit 136 shown in the embodiment of FIG. From the pilot signal 122 and the transmission radio signal 114, level detectors 142, 14
4 detects a pilot strength signal 146 of voltage x volts and a transmit strength signal 148 of voltage y volts, respectively. Both pilot strength signal 146 and transmission strength signal 148 are input to division circuit 150, and division signal 152 of voltage y / x volts is output from this circuit 150. The division signal 152 is the subtraction circuit 158 subtracting the reference signal 156 of the voltage z volt output from the reference voltage source 154, and becomes the error signal 160 of the voltage x / y-z volt. This error signal 160 is the intensity adjuster 16
Entered in 2. The intensity adjuster 162 is composed of an attenuator using a PIN diode and a high frequency amplifier, and functions as an amplifier and an attenuator when the voltage of the error signal 160 is negative and positive, respectively, and its amplification amount or attenuation amount is The error signal 160 is proportional to the absolute value of the voltage.

In the transmission intensity control circuit 136 of FIG. 3, the voltage of the reference signal 156 is set to 1 volt. In this case, when the strength of the transmission radio signal 306 output from the antenna 310 shown in FIG. 2 is 100 mW or less, the transmission strength signal 144 becomes smaller than the pilot strength signal 142 and the division signal 152 becomes 1 or less. Become. Therefore, the error signal 160 becomes negative, the intensity adjuster 162 acts as an amplifier, and the intensity of the radio signal 104 is amplified until the intensity of the transmission radio signal 306 becomes 100 mW. On the contrary, when the intensity of the transmitted wireless signal 306 is 100 mW or more, the intensity adjuster 16
2 acts as an attenuator and the strength of the transmitted radio signal is 100 m
The intensity of the wireless signal 104 is attenuated until it reaches W. Figure 3
In, for example, when the voltage of the reference signal 156 is changed to 0.1 volt or 10 volt, the transmission radio signal 306
The output intensity of each is stabilized to 10 mW or 1 W, respectively.

FIG. 4 is a block diagram of the third embodiment of the present invention. In the base station device of this mobile communication system, the frequency conversion of the radio signal is performed by the antenna units 300B and 301, and the pair of optical fiber transmission lines 200 and 202 are shared by the two antenna units 300B and 301. .
Radio signals 104 and 105 having frequencies of 200 MHz and 300 MHz are output from the two modulators 102 and 103 of the radio transmission / reception unit 100B, multiplexed by the multiplexer 117, and then input to the electrical / optical conversion circuit 106. . The optical signal 204 output from the electrical / optical conversion circuit 106 is distributed to the antenna units 300B and 301 by the star-shaped optical fiber transmission line 200. Antenna part 300
In B, the frequency of the radio signal output from the optical / electrical conversion circuit 302 is set to 200 by the band pass filter 340.
Only the radio signal 342 of MHz is taken out and supplied to the frequency conversion circuit 350. The frequency conversion circuit 350 includes a local oscillator 352 having an oscillation frequency of 600 MHz and a mixer 3
It is composed of a bandpass filter 356 in the 54,800 MHz band and outputs a radio signal 342 of 200 MHz to 8
The transmission wireless signal 306 in the 00 MHz band is frequency-converted.
Similarly, the antenna unit 301 has an oscillation frequency of 500 MHz.
The frequency conversion circuit 351 using the local oscillator 353 of
The frequency is converted into a transmission radio signal 307 in the MHz band.

On the other hand, the antenna 31 of the antenna section 300B
Received radio signal 312 of 850 MHz band received in No. 4
Is a local oscillator 352, mixer 364, 250 MHz
The frequency is converted to a frequency of 250 MHz by the frequency conversion circuit 360 formed by the band pass filter 366. The frequency-converted received radio signal and a part 358 of the output of the local oscillator are multiplexed by the multiplexer 368, and the optical signal 206 is converted by the electric / optical conversion circuit 324.
Is converted to the wireless communication unit 100 and further transmitted to the wireless transmission / reception unit 100. Similarly, the antenna unit 301 receives the received wireless signal 313 in the 850 MHz band by the frequency conversion circuit 361 at 350 M.
The frequency is converted to Hz, and further converted into an optical signal 207 together with the local oscillator output 359 having a frequency of 500 MHz and sent to the wireless transmission / reception unit 100B.

The radio transmitter / receiver 100B has band-pass filters 170, 171, 1 having pass frequencies of 250 MHz, 350 MHz, 600 MHz and 500 MHz, respectively.
72 and 173 to receive radio signals 112, 11
3 and local oscillator outputs 174,175. Of these, the frequencies of the local oscillator outputs 174 and 175 are detected by the frequency discriminators 176 and 177, respectively. The transmission frequency control circuits 178 and 179 output frequency control signals 180 and 181 in response to the outputs of the frequency discriminators 176 and 177, respectively, and thereby the VCO which is a carrier signal generator in the modulators 102 and 103.
The frequency of the radio signals 104 and 105 is controlled by controlling the oscillation frequency of the (voltage controlled oscillator). For example, if the frequency of the local oscillator output 174 is 600 MHz, x
When the frequency is lowered by MHz, the transmission frequency control circuit 178
Controls the frequency of the radio signal 104 output from the modulator 102 to be (200 + x) MHz. As described above, in this base station device, negative frequency feedback is applied to the transmission radio signal 306, and even if the oscillation frequency of the local oscillator 352 changes, the frequency of the transmission radio signal 306 in the antenna unit 300B is stable at 800 MHz. Be converted. Similarly, the frequency of the radio signal 105 output from the modulator 103 is controlled by the frequency control circuit 179, and the frequency of the transmission radio signal 307 in the antenna unit 301 is 800.
Stabilized to MHz.

FIG. 5 is a block diagram of the fourth embodiment of the present invention. In the base station apparatus of the embodiment of FIG. 4 described above, the frequency of the transmission radio signal is stabilized by transmitting a part of the local oscillator output from the antenna units 300B and 301 to the radio transmission / reception unit 100B. Then, the frequency of the transmission wireless signals 306 and 307 is stabilized by transmitting the frequency-converted transmission wireless signals 308 and 309 from the antenna units 300B and 301 to the wireless transmission / reception unit 100C.

In the antenna section 300B of FIG. 5, a part of the transmission radio signal 306 is. The signals are demultiplexed by the demultiplexer 320, further demultiplexed by the multiplexer 322 with the received radio signal 312, and input to the frequency conversion circuit 360. The frequency conversion circuit 360 includes a band pass filter 366 having a pass band at a local oscillator 352 having an oscillation frequency of 600 MHz, mixers 364, 1400 MHz and 250 MHz.
By which the 800 MHz transmitted radio signal 308 and the 850 MHz received radio signal 312 are respectively 1400 MHz and 250 M.
It is converted into a frequency signal of Hz. The frequency-converted transmission wireless signal 308 and reception wireless signal 312 are both converted into an optical signal 206 by the electric / optical conversion circuit 324 and sent to the wireless transmission / reception unit 100C. Similarly, in the antenna unit 301, the local oscillator 3 with an oscillation frequency of 500 MHz is
A frequency conversion circuit 361 having 53 as a local oscillation signal source causes a transmission radio signal 309 of 800 MHz and a frequency of 85
The received radio signal 313 of 0 MHz has a frequency of 130
Frequency conversion is performed on signals of 0 MHz and 350 MHz.

The radio transmitter / receiver 100C includes an antenna unit 30.
0B, transmitted radio signal 114 transmitted from 301,
115 and the received radio signals 112 and 113 are separated by band pass filters 132, 133, 170 and 171 respectively. Of these, the transmission radio signal 114 having a frequency of 1400 MHz is transmitted to the frequency detector 18 together with the radio signal 104 having a frequency of 200 MHz output from the modulator 102.
Entered in 2. The frequency detector 182 detects the oscillation frequency of the local oscillator 352 of the antenna unit 300B, and the transmission frequency control circuit 178 is similar to the embodiment of FIG.
Controls the frequency of the radio signal 104 and stabilizes the frequency of the transmission radio signal 306. Similarly, the frequency detector 183 is configured to transmit the transmitted radio signal 1 having a frequency of 1300 MHz.
15 and a radio signal 105 with a frequency of 200 MHz,
The oscillation frequency of the local oscillator 353 is detected. The transmission frequency control circuit 179 controls the frequency of the radio signal 105 in response to the output of the frequency detector 183 and stabilizes the frequency of the transmission radio signal 307.

FIG. 6 is a block diagram of the frequency detector 182 shown in the embodiment of FIG. Transmission radio signal 114 of frequency 1400 MHz and radio signal 104 of frequency 200 MHz
Is frequency-converted by the mixer 184, and further 12
Band pass filter 186 having 00 MHz band as pass band
Entered in. The frequency of the signal passing through the bandpass filter 186 is the frequency of the transmission wireless signal 114 minus the frequency of the wireless signal 104. This frequency is twice the oscillation frequency of the local oscillator 352 of the antenna unit 300B in FIG. Further, this band pass filter 18
The output from 6 is a 1/2 divider 188 and 600M
It is input to the bandpass filter 190 whose pass band is the Hz band. The frequency of the signal output from the bandpass filter 190 is equal to the oscillation frequency of the local oscillator 352. The output of the bandpass filter 190 is the frequency discriminator 176.
And the oscillation frequency of the local oscillator 352 is detected. The output of the frequency discriminator 176 is the frequency control circuit 1
Wireless signal 1 inputted to the wireless communication terminal 78 in the same manner as in the embodiment of FIG.
The frequency of 04 is controlled and the frequency of the transmission radio signal 306 is stabilized.

The present invention includes various modifications in addition to the above embodiments. For example, the transmission strength control circuit 136 used in the embodiment of FIG. 2 and shown in FIG. 3 is merely one example, and even if the division circuit 150 is changed to a subtraction circuit, the strength of the transmission radio signal 306 is stable. Is possible. The main point of the invention shown in this embodiment is that the output intensity of the transmission wireless signal 306 is detected by the transmission wireless signal 114 and the pilot signal 122 sent from the antenna unit 300, and the output intensity of the transmission wireless signal 306 is negatively used. This is to stabilize the output intensity of the transmission wireless signal 306 by performing feedback control.

The frequency detector 182 used in the embodiment of FIG. 5 and shown in FIG. 6 is also an example. For example, even if the 1/2 frequency divider 188 and the band pass filter 190 are omitted, the transmission radio signal is omitted. Frequency stabilization of 306 is possible.

Further, in the embodiment of FIGS. 4 and 5, the two antenna units 300B and 301 share the pair of optical fiber transmission lines 200 and 202, but the required performance of the applied mobile communication system is satisfied. Within the range, the number of antenna units sharing a pair of optical fiber transmission lines can be set arbitrarily.

In addition, the first to fourth embodiments (FIG. 1, FIG.
In the embodiments of FIGS. 2, 4 and 5, two antennas 310 for transmission and reception are provided in the antenna section of the base station device.
Although 314 is used, a duplexer or a circulator can be used to transmit and receive a radio signal with one antenna.

[0037]

As described above, according to the present invention, in the radio base station apparatus of the mobile communication system in which the antenna section and the radio transmission / reception section are connected by the optical fiber transmission line, the data is transmitted from the antenna section. Since the wireless transmission / reception unit has means for monitoring / controlling the wireless signal, there is an effect that the antenna unit does not need the function of monitoring / controlling the transmission wireless signal. Therefore, not only can the antenna section be miniaturized, but the number of parts is reduced and the antenna section is often installed outdoors, so that the reliability of the antenna section, which is difficult to maintain, can be improved. This has the effect of facilitating maintenance of the device.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a second embodiment of the present invention.

FIG. 3 is a transmission strength control circuit 136 shown in the embodiment of FIG.
It is a block diagram of.

FIG. 4 is a configuration diagram of a third embodiment of the present invention.

FIG. 5 is a configuration diagram of a fourth embodiment of the present invention.

6 is a configuration diagram of a frequency detector 182 shown in the embodiment of FIG.

[Explanation of symbols]

100, 100A, 100B, 100C Radio transmitter / receiver 102, 103 Modulator 104, 105, 342, 343 Radio signal 106, 324, 325 Electric / optical conversion circuit 110, 302, 303 Optical / electric conversion circuit 118, 119 Demodulator 120 Spectrum analyzer 122,332 Pilot signal 136 Transmission strength control circuit 142,144 Level detector 146 Pilot strength signal 148 Transmission strength signal 150 Division circuit 152 Division signal 154 Reference voltage source 156 Reference signal 158 Subtraction circuit 160 Error signal 162 Strength Regulator 174,175,358,359 Local oscillator output 176,177 Frequency discriminator 178,179 Transmission frequency control circuit 180,181 Frequency control signal 182,183 Frequency detector 188 Half frequency divider 200, 02 optical fiber transmission line 204,206,207 optical signal 300, 300A, 300B, 301 antenna 304 and 305 high power amplifier 306,307,308,309,114,115
Transmission wireless signal 312, 313, 112, 113 Reception wireless signal 310, 311, 314, 315 Antenna 318, 319 Low noise amplifier 330 Oscillator 334 Limiter circuit 350, 351, 360, 361 Frequency conversion circuit 352, 353 Local oscillator 354, 355 , 364, 365, 184 Mixer 116, 320, 321 Demultiplexer 117, 322, 323, 336, 368, 369
Multiplexer 130, 132-134, 170-173, 186, 1
90, 316, 317, 340, 341, 356, 357, 366, 367
Bandpass filter 400 Mobile terminal 500 Switching station 502, 504 Telephone signal

Claims (4)

[Claims] 1. A modulation means for generating a first radio signal modulated by a signal including a call signal, a first electrical / optical conversion means for converting the first radio signal into a first optical signal, and a second optical signal for the second optical signal. A wireless transmission / reception unit having an optical / electrical conversion unit for converting into two wireless signals and a demodulation unit for demodulating a signal including a call signal from the second wireless signal; and a unit for transmitting the first optical signal from the wireless transmission / reception unit. 1 optical fiber transmission line, transmission radio signal generation means for converting the first optical signal from the first optical fiber transmission line into a transmission radio signal, transmission antenna for transmitting the transmission radio signal to a mobile station, the mobile station A reception antenna for receiving a reception radio signal from the antenna, and an antenna section having a second electric / optical conversion means for converting the reception radio signal into the second optical signal; and the second optical signal from the antenna section for wireless transmission and reception. In a wireless base station device of a mobile communication system having a second optical fiber transmission path for transmitting to a receiving section, the second electrical / optical converting means of the antenna section further includes the receiving wireless signal and the transmitting wireless signal generating means. A part of the transmission wireless signal from the second wireless signal is converted into the second optical signal, and the wireless transmission / reception unit further has means for monitoring the transmission wireless signal included in the second wireless signal. A base station device of a mobile communication system characterized. 2. Modulating means for generating a first radio signal modulated by a signal including a call signal, first electric / optical converting means for converting the first radio signal into a first optical signal, and second optical signal for the second optical signal. A wireless transmission / reception unit having an optical / electrical conversion unit for converting into two wireless signals and a demodulation unit for demodulating a signal including a call signal from the second wireless signal; and a unit for transmitting the first optical signal from the wireless transmission / reception unit. 1 optical fiber transmission line, transmission radio signal generation means for converting the first optical signal from the first optical fiber transmission line into a transmission radio signal, transmission antenna for transmitting the transmission radio signal to a mobile station, the mobile station A reception antenna for receiving a reception radio signal from the antenna, an antenna section including a second electric / optical conversion means for converting the reception radio signal into the second optical signal, and the radio transmission / reception section for receiving the second optical signal from the antenna section. In a radio base station device of a mobile communication system having a second optical fiber transmission line for transmitting to a second optical fiber transmission path, the second electric / optical conversion means of the antenna unit further includes the reception radio signal from the transmission radio signal generation means. Transmission wireless signal strength detection, which has means for converting a part of the transmission wireless signal into the second optical signal, and the wireless transmission / reception unit further detects the strength of the transmission wireless signal included in the second wireless signal. A radio base station apparatus for a mobile communication system, comprising: means and radio signal strength control means for controlling the strength of the first radio signal in response to the detected transmission radio signal strength. 3. A modulation means for generating a first radio signal modulated by a signal containing a call signal, a first electrical / optical conversion means for converting the first radio signal into a first optical signal, and a second optical signal for the second optical signal. A wireless transmission / reception unit having a first optical / electrical conversion unit for converting into two wireless signals and a demodulation unit for demodulating a signal including a call signal from the second wireless signal; and transmitting the first optical signal from the wireless transmission / reception unit. A first optical fiber transmission line,
A third optical signal from the first optical fiber transmission line
Second optical / electrical converting means for converting into a radio signal, local oscillator means for producing a local oscillation signal, and transmission radio having a frequency different from that of the third radio signal in response to the local oscillation signal and the third radio signal First frequency conversion means for generating a signal, a transmission antenna for transmitting the transmission radio signal to a mobile station, a reception antenna for receiving a reception radio signal from the mobile station, a reception radio signal having a frequency different from that of the reception radio signal. A second frequency conversion means for converting the fourth radio signal into the second optical signal and a second electric / optical conversion means for converting the fourth radio signal into the second optical signal; and the second optical signal from the antenna section. In a wireless base station device of a mobile communication system having a second optical fiber transmission path for transmitting to the wireless transmission / reception unit, the second electric / optical conversion means of the antenna unit is And a means for converting a part of the local oscillation signal from the local oscillator means into the second optical signal together with the fourth radio signal, wherein the radio transmission / reception section further includes the second radio signal. A local oscillation signal frequency detecting means for detecting the frequency of the local oscillation signal including; and a radio signal frequency control means for controlling the frequency of the first radio signal in response to the detected local oscillation signal frequency. A radio base station device of a mobile communication system characterized. 4. A modulation means for generating a first radio signal modulated by a signal including a call signal, a first electrical / optical conversion means for converting the first radio signal into a first optical signal, and a second optical signal as a second optical signal. A wireless transmission / reception unit having a first optical / electrical conversion unit for converting into two wireless signals and a demodulation unit for demodulating a signal including a call signal from the second wireless signal; and transmitting the first optical signal from the wireless transmission / reception unit. A first optical fiber transmission line,
A third optical signal from the first optical fiber transmission line
Second optical / electrical converting means for converting into a radio signal, local oscillator means for producing a local oscillation signal, and transmission radio having a frequency different from that of the third radio signal in response to the local oscillation signal and the third radio signal First frequency conversion means for generating a signal, a transmission antenna for transmitting the transmission radio signal to a mobile station, a reception antenna for receiving a reception radio signal from the mobile station, a reception radio signal having a frequency different from that of the reception radio signal. A second frequency conversion means for converting the fourth radio signal into the second optical signal and a second electric / optical conversion means for converting the fourth radio signal into the second optical signal; and the second optical signal from the antenna section. In a wireless base station device of a mobile communication system having a second optical fiber transmission line for transmitting to the wireless transmission / reception unit, the second frequency conversion means of the antenna unit is the local unit. The local oscillator signal is supplied from oscillator means, and further has means for converting a part of the transmission radio signal from the first frequency conversion means into the fourth radio signal together with the reception radio signal, and the radio transmission / reception unit. Further, a transmission radio signal frequency detecting means for detecting the frequency of the transmission radio signal included in the second radio signal, and controlling the frequency of the first radio signal in response to the detected transmission radio signal frequency. A radio base station apparatus for a mobile communication system, comprising: radio signal frequency control means.