JP2002353897A - Electromagnetic wave transmitter, electromagnetic wave receiver and radio communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the electromagnetic wave transmitter/receiver of a millimeter waveband, whose communication speed is not limited by component parts and the band of a transmission cable. SOLUTION: In the electromagnetic wave transmitter 101, a data optical signal with which a data signal is overlapped is inputted from an optical fiber 111, converted into a radio signal and radiated from a transmission side antenna 114. The transmitter is provided with an optical signal generator 112 for generating an optical sub-carrier signal being a radio carrier and a radio signal generator 113 for inputting the optical sub-carrier signal generated in the optical signal generator 112 and the data optical signal and for outputting the radio signal with which the data signal is overlapped to the transmission side antenna 114.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic wave transmitter, an electromagnetic wave receiver, and a radio communication system, and more particularly, to an electromagnetic wave transmitter, an electromagnetic wave receiver, and a radio communication system which constitute a high-speed broadband radio communication system. .

[0002]

2. Description of the Related Art Wireless communication systems that do not require installation of cables and do not limit the positions of terminals are rapidly spreading. However, when a large amount of information such as an image and a video is handled, the communication speed is limited in a wireless communication system using microwaves of several GHz. For this reason, studies have been made to increase the communication speed by using millimeter waves having a higher frequency than microwaves.

FIG. 15 shows a radio transceiver used in a conventional wireless home network. For example,
1 shows a wireless home network system using a frequency of 60 GHz. The transmission circuit and the reception circuit used in such a system share a single antenna and switch between transmission and reception by a T / R switch. However, a simplified circuit will be described here.

[0004] In the wireless transmitter 1501, the data signal transmitted via the high-frequency cable 1511 is divided into a carrier signal generated by an oscillator 1512 and a mixer 1513.
Are superimposed. The superimposed data signal is amplified by an amplifier 1514 and then radiated into space by an antenna 1515 as an electromagnetic wave. The wireless signal received by the antenna 1525 of the wireless receiver 1502 is amplified by the amplifier 1524, and the data signal is demodulated in the mixer 1523 by the carrier signal generated by the oscillator 1522, and output to the high-frequency cable 1521.

[0005]

In the above-mentioned millimeter-wave radio communication system, the radio transceiver formed by an electric circuit has the following problems. First, as the bandwidth of the data signal increases, it becomes difficult to transmit data over long distances using an electric cable such as a coaxial cable or a twisted pair cable.

FIG. 16 shows a standard of a cable conventionally used in Ethernet. As the transmission speed increases from 10 Mbps to 1 Gbps, the transmission distance of the electric cable becomes shorter. The transmission distance by electric cable is
Compared with the standard of the same transmission speed, it is shorter than the transmission distance of the optical cable. In particular, at 1 Gbps, electric cables can transmit only 25 m.

Second, when the band of the data signal increases,
The bandwidth of the components of the wireless transceiver also needs to be expanded.
The wireless communication system shown in FIG. 15 requires a mixer, an oscillator, and an amplifier in the millimeter wave band. Currently, the amplifier has 6
The 0 GHz region is in the development stage, and there are only research reports at 100 GHz and above. Also, the oscillator is 100
GHz and above are at the research level. As described above, when the frequency to be used is 100 GHz or more, there is a problem that the band of the components of the wireless transceiver formed by the electric circuit is insufficient.

At present, a wireless communication system with a frequency of 60 GHz is being developed, but the maximum communication speed in this system is 500 Mbps, and it is difficult to perform communication at 1 Gbps or more such as Gigabit Ethernet (registered trademark). It is.

The present invention has been made in view of such a problem, and an object of the present invention is to limit a communication speed in a wireless communication system using a millimeter wave band by the bandwidth of components and transmission cables. It is an object of the present invention to provide an electromagnetic wave transmitter, an electromagnetic wave receiver, and a wireless communication system that do not need to operate.

[0010]

According to the present invention, in order to achieve the above object, according to the first aspect of the present invention, a data optical signal on which a data signal is superimposed is inputted from an optical fiber, and a radio signal is inputted. In an electromagnetic wave transmitter that converts the signal into a signal and radiates from a transmitting antenna, an optical signal generator that generates an optical subcarrier signal serving as a wireless carrier, the optical subcarrier signal generated by the optical signal generator, and the data A wireless signal generator for receiving an optical signal and outputting a wireless signal on which the data signal is superimposed to the transmitting antenna.

According to this configuration, an optical subcarrier signal having a frequency of 100 GHz or more is generated by the optical signal generator, so that a subcarrier signal in a band that is difficult to handle in an electrical system can be used.

According to a second aspect of the present invention, in the electromagnetic wave transmitter, a data optical signal on which a data signal is superimposed is input from an optical fiber, converted into a radio signal, and radiated from a transmitting antenna. And a data signal modulated optical signal generator to be superimposed on an optical subcarrier signal to be a radio carrier, and an optical subcarrier signal on which the data optical signal is superimposed from the data signal modulated optical signal generator,
A wireless signal generator that outputs a wireless signal on which the data signal is superimposed to the transmitting antenna.

According to this configuration, in the data signal modulated optical signal generator, the data optical signal is superimposed on the optical subcarrier signal having a frequency of 100 GHz or more, so that the subcarrier signal in a band that is difficult to handle in an electrical system is used. Can be used.

According to a third aspect of the present invention, in the wireless signal generator according to the first aspect, the first O / E converter for converting the data optical signal into a first electric signal; An optical modulator that modulates the optical subcarrier signal with the first electric signal converted by the O / E converter, and converts the optical subcarrier signal modulated by the optical modulator into a second electric signal A second O / E converter that performs
And an amplifier for amplifying the second electric signal converted by the / E converter and outputting a wireless signal on which the data signal is superimposed.

According to a fourth aspect of the present invention, the wireless signal generator according to the first aspect further comprises: an optical coupler for multiplexing the data optical signal and the optical subcarrier signal to output an optical signal; A third O / E converter that mixes the optical signal output from the optical coupler and converts the optical signal into an electric signal; and amplifies the electric signal converted by the third O / E converter to generate the data signal. An amplifier that outputs a radio signal on which the signal is superimposed.

According to a fifth aspect of the present invention, the wireless signal generator and the optical signal generator according to the third or fourth aspect comprise the same module, and the optical signal transmitted through the module is , Transmitted by an optical fiber or an optical waveguide.

According to a sixth aspect of the present invention, the second O / E converter and the amplifier according to the third aspect are constituted by the same module, and are connected to the optical modulator by an optical fiber. It is characterized by being.

According to a seventh aspect of the present invention, the third O / E converter and the amplifier according to the fourth aspect are constituted by the same module, and are connected to the optical modulator by an optical fiber. It is characterized by being.

According to an eighth aspect of the present invention, in the second aspect, the data signal modulated optical signal generator comprises: a fourth O / E converter for converting the data optical signal into a fourth electric signal; The fourth O / E converter converts the fourth
And an optical signal generator for generating an optical subcarrier signal on which the data signal is superimposed, wherein the wireless signal generator has the data optical signal superimposed thereon from the optical signal generator. A fifth O / E converter for inputting an optical subcarrier signal and converting it into a fifth electric signal;
And an amplifier that amplifies the fifth electric signal converted by the O / E converter and outputs a wireless signal on which the data signal is superimposed.

According to a ninth aspect of the present invention, the second O / E converter and the amplifier according to the third, fifth or sixth aspect of the invention are connected to a sixth O / E converter using a single carrier traveling photodiode. The sixth O / E converter receives the optical subcarrier signal modulated by the optical modulator and outputs a radio signal on which the data signal is superimposed.

According to a tenth aspect of the present invention, there is provided the optical signal generator according to any one of the first to third aspects,
The optical subcarrier signal is generated by multiplying an optical signal generated by an active mode-locked laser, a passive mode-locked laser, or a mode-locked laser.

According to an eleventh aspect of the present invention, in the optical signal generator according to any one of the first to third aspects,
By mixing laser oscillation lines of two different wavelengths,
It is characterized by generating an optical subcarrier signal.

According to a twelfth aspect of the present invention, in the electromagnetic wave receiver for demodulating a radio signal received by a receiving antenna, converting the signal into a data optical signal on which a data signal is superimposed, and outputting the data signal to an optical fiber, A millimeter wave detector that detects the radio signal input from the side antenna and converts the radio signal into an electric signal, an amplifier that amplifies the electric signal converted by the millimeter wave detector, and the electric signal that is amplified by the amplifier To an optical signal, and an E / O converter that outputs the data optical signal on which the data signal is superimposed to the optical fiber.

According to a thirteenth aspect of the present invention, in the millimeter wave detector according to the twelfth aspect, when the local oscillation signal is generated, the millimeter wave detector detects the radio signal with the oscillator and the local oscillation signal from the oscillator. And a mixer for converting the signal into an electric signal.

According to a fourteenth aspect of the present invention, there is provided the electromagnetic wave transmitter according to any one of the first to eleventh aspects and the electromagnetic wave receiver according to the twelfth or thirteenth aspect, wherein the transmitting side antenna and the receiving side are provided. The antenna uses one common antenna, and switches an output of the electromagnetic wave transmitter and an input of the electromagnetic wave receiver by a T / R switch connected to the common antenna.

According to a fifteenth aspect of the present invention, there is provided a wireless terminal having a microwave transmitter and the electromagnetic wave receiver according to the twelfth or thirteenth aspect, and an electromagnetic wave transmitter according to any one of the first to eleventh aspects. , A microwave receiver, and an access point having a converter for converting an output of the microwave receiver into an optical signal.

[0027]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the present invention,
The data signal is a data optical signal superimposed on the optical signal, and is input to a wireless signal generator or an optical signal generator through an optical fiber. After being superimposed on the optical subcarrier signal, the data optical signal is converted into an electromagnetic wave and emitted to space. The electromagnetic wave is converted into an electric signal by an antenna and a detector, and then converted into a data optical signal by an E / O converter.

FIG. 1 shows a wireless communication system according to the first embodiment of the present invention. The electromagnetic wave transmitter 101 has a wireless signal generator 113 connected to an optical fiber 111 for inputting a data optical signal, and an optical signal generator 112 connected to the wireless signal generator 113 for generating an optical subcarrier signal. An antenna 114 for radiating electromagnetic waves is connected to the radio signal generator 113. Also, the electromagnetic wave receiver 1
Numeral 02 has an antenna 124 for receiving an electromagnetic wave, and a radio signal receiver 123 connected to the antenna 124, and an optical fiber 121 for outputting a data optical signal is connected to the radio signal receiver 123.

With such a configuration, the data optical signal is
The signal is input from the optical fiber 111 to the wireless signal generator 113. The optical subcarrier signal generated by the optical signal generator 112 is also input to the radio signal generator 113. The radio signal generator 113 generates a radio signal on which a data signal is superimposed from the input data optical signal and optical subcarrier signal, and transmits the radio signal to the antenna 114. The radio signal transmitted from the antenna 114 is received by the antenna 124 of the electromagnetic wave receiver 102, converted into a data optical signal by the radio signal receiver 123, and output to the optical fiber 121.

In the first embodiment, an optical fiber Gigabit Ethernet 1000Base-
SX standard was used. The carrier frequency and the subcarrier frequency used were 120 GHz millimeter waves. According to the first embodiment, long-distance data signal transmission is all performed by Gigabit Ethernet, which is an optical fiber, so that long-distance transmission can be performed as compared with transmission using an electric cable. An optical signal of 120 GHz serving as a subcarrier is generated by an optical signal generator 112. Signals with a frequency of 100 GHz or higher are very difficult to generate electrically, but are relatively easy using optical technology.

In the first embodiment, the 1000Base-SX standard is used as the data optical signal. However, the data optical signal is an optical signal transmitted by an optical fiber, and is an optical signal having a bandwidth equal to or less than the band of the components of the first embodiment. Any optical signal may be used. Although an optical signal having a frequency of 120 GHz is used as the subcarrier signal, it goes without saying that another unmodulated optical signal may be used as long as a high-frequency data signal can be transmitted.

In the first embodiment, the optical signal generator 112
Used an active mode-locked laser and an optical multiplier.
However, a self-excited oscillation laser such as a passive mode-locked laser or a different generation method such as mixing using laser oscillation lines of two different wavelengths may be used. Also, from the optical signal generator 112 to the wireless signal generator 1
Transmission of the optical signal to 13 may use a transmission medium such as an optical fiber, an optical waveguide, or a spatial transmission.

FIG. 2 shows a wireless communication system according to a second embodiment of the present invention. The electromagnetic wave transmitter 201 includes a data signal modulation optical signal generator 212 connected to an optical fiber 211 for inputting a data optical signal, and a radio signal generator for outputting a radio signal connected to the data signal modulation optical signal generator 212. 213, and an antenna 214 for radiating electromagnetic waves is connected to the wireless signal generator 213. The configuration of the electromagnetic wave receiver 102 is the same as that of the first embodiment shown in FIG.

With such a configuration, the data optical signal is
Data signal modulated optical signal generator 21 from optical fiber 211
2 is input. Data signal modulated optical signal generator 212
Outputs an optical subcarrier signal on which the input data optical signal is superimposed, and inputs the optical subcarrier signal to the radio signal generator 213. The wireless signal generator 213 generates a wireless signal on which the data signal is superimposed, and transmits the generated wireless signal to the antenna 214. Antenna 214
Is received by the antenna 124 of the electromagnetic wave receiver 102, is converted into a data optical signal by the wireless signal receiver 123, and is output to the optical fiber 121.

FIG. 3 shows a first embodiment of the electromagnetic wave transmitter in the wireless communication system according to the first embodiment of the present invention. The radio signal generator 113 in the electromagnetic wave transmitter 101 shown in FIG.
A converter 301, an optical modulator 302 that modulates an optical signal from the optical signal generator 112 with an electric signal from the O / E converter 301, and an optical modulator 302 connected to an output of the optical modulator 302.
It comprises an / E converter 303 and an amplifier 304 that amplifies the output of the O / E converter 303 and outputs it to the antenna 114.

With such a configuration, the data optical signal is
After being input from the optical fiber 111 to the O / E converter 301 and converted into an electric signal, it is applied to the optical modulator 302. As a result, the optical subcarrier signal input from the optical signal generator 112 is superimposed on the data signal superimposed on the data optical signal by the optical modulator 302. The optical subcarrier signal is converted into an electric signal by the O / E converter 303 and then amplified by the amplifier 304.
The signal is transmitted to the antenna 114.

As the light modulator 302, an ultra-high-speed light intensity modulator using a LiNbO ₃ crystal was used. Optical modulator, O /
The band required by the E converter is the band of the data signal. For example, in the first embodiment, the frequency is about 1 GHz, and components in these bands have been put to practical use. As described above, since all the optical subcarrier signals having an ultra-high frequency are processed by the optical technology, a wireless communication system with a communication speed of 1 Gbps can be realized by using the wireless signal generator of this embodiment.

In this embodiment, the O / E converter 3
Although the amplifier 304 is used in the latter stage of the O / E converter 303, if a single carrier traveling photodiode featuring high speed and high output is used in the O / E converter 303, the amplifier 30 in the latter stage can be used.
4 can be omitted. Further, in this embodiment, after the data optical signal is O / E converted, the optical modulator 30 is directly used.
2, but may be input to the optical modulator 302 after up-conversion using a mixer or the like.

FIG. 4 shows a second embodiment of the electromagnetic wave transmitter in the wireless communication system according to the first embodiment of the present invention. The radio signal generator 113 in the electromagnetic wave transmitter 101 shown in FIG. 1 includes an optical coupler 402 for multiplexing the output of the optical fiber 111 and the output of the optical signal generator 112, and mixing the output of the optical coupler 402 to generate electric power. O to convert to signal
It comprises an / E converter 403 and an amplifier 404 which amplifies the output of the O / E converter 403 and outputs it to the antenna 114.

With such a configuration, the data optical signal is
A radio signal on which a data signal is superimposed by an O / E converter 403 having a mixer function after being input to an optical coupler 402 from an optical fiber 111 and added to an optical subcarrier signal input from an optical signal generator 112 Is converted to According to this embodiment, the O / E converter for the data optical signal can be omitted.

FIG. 5 shows a third example of the electromagnetic wave transmitter in the wireless communication system according to the first embodiment of the present invention. In the electromagnetic wave transmitter 101, the wireless signal generator 113 and the optical signal generator 112 of the first embodiment shown in FIG. The optical signal generator 112, the optical modulator 302, and the O / E converter 303 are connected by an optical waveguide. According to this embodiment, since the optical signal generator 112, the optical modulator 302, and the O / E converter 303 are modularized, the size of the electromagnetic wave transmitter 101 can be reduced.

Similarly, the radio signal generator 113 and the optical signal generator 112 of the second embodiment shown in FIG. 4 can be configured as the same module to constitute the electromagnetic wave transmitter 101. The optical signal generator 112, the optical coupler 402 and the O /
Since the E converter 403 and the E converter 403 can be configured by the same module, the electromagnetic wave transmitter 101 can be reduced in size.

FIG. 6 shows a fourth embodiment of the electromagnetic wave transmitter in the wireless communication system according to the first embodiment of the present invention. The electromagnetic wave transmitter 101 has a configuration in which an amplifier 304 and an O / E converter 303 are integrated, and an optical modulator 302
The O / E converter 301 and the optical signal generator 112 are not in the same device, and the optical modulator 302 and the O / E converter 303 are connected by an optical fiber. According to this embodiment, it is possible to provide a system in which a base station performs a modulating unit that performs optical modulation by using a simple configuration in which a transmitter includes only a radio unit that outputs a radio signal.

FIG. 7 shows a fifth embodiment of the electromagnetic wave transmitter in the wireless communication system according to the second embodiment of the present invention. The data signal modulated optical signal generator 212 in the electromagnetic wave transmitter 201 shown in FIG. 2 includes an O / E converter 701 connected to the optical fiber 211 and an O / E converter 7.
And an optical signal generator 702 for generating an optical subcarrier signal modulated by the output of the optical subcarrier signal 01. The wireless signal generator 213 includes an O / E converter 703 connected to the data signal modulated optical signal generator 212, and an amplifier 704 that amplifies the output of the O / E converter 703 and outputs the amplified output to the antenna 214. .

With such a configuration, the data optical signal is
After being input from the optical fiber 211 to the O / E converter 701 and converted into an electric signal, it is applied to the optical signal generator 702. The optical signal generator 702 superimposes the data signal superimposed on the data optical signal on the optical subcarrier signal and outputs the resulting signal to the wireless signal generator 213. The radio signal generator 213 converts the input optical subcarrier signal into an electric signal by the O / E converter 703,
4 and transmitted to the antenna 214.

The optical signal generator 702 uses an active mode-locked laser. This laser can generate an optical subcarrier signal on which a data signal is superimposed by input of an electrical data signal. Optical signal generating means such as a passive mode-locked laser may be used as long as it has a similar function.

In this embodiment, the data signal modulated optical signal generator 212 and the radio signal generator 213 are constituted by separate modules and connected by optical fibers.
Data signal modulated optical signal generator 212 and wireless signal generator 2
13 may be integrated into a module, and both may be connected by a transmission medium such as an optical waveguide. According to this embodiment, an expensive optical modulator can be omitted, so that an inexpensive electromagnetic wave transmitter can be configured.

FIG. 8 shows a first embodiment of the electromagnetic wave receiver in the radio communication system according to the first or second embodiment of the present invention. The electromagnetic wave receiver 10 shown in FIG. 1 or FIG.
2 has a wireless signal receiver 123 connected to an antenna 124 for receiving electromagnetic waves, and the wireless signal receiver 123
A millimeter wave detector 801 connected to the antenna 124, an amplifier 802 for amplifying the output of the millimeter wave detector 801 and an optical fiber 121 for converting the output of the amplifier 802 to an optical signal.
And an E / O converter 803 for output to

With such a configuration, the radio signal received by the antenna 124 is detected by the millimeter wave detector 801 and amplified by the amplifier 802. Furthermore, E
The data optical signal demodulated into an optical signal by the / O converter 803 is output to the optical fiber 121.

In this embodiment, the millimeter wave detector 801
Used a fast response Schottky barrier diode. Further, the wireless signal receiver 123 shown in FIG. 8 may use an MMIC in which components are monolithically arranged.

FIG. 9 shows a second embodiment of the electromagnetic wave receiver in the radio communication system according to the first or second embodiment of the present invention. In this embodiment, a mixer 901 and an oscillator 902 are used to detect a wireless signal. Compared with the first embodiment shown in FIG. 8, there is an advantage that the detection sensitivity is high and the band is wide. However, there are disadvantages such as the necessity of the oscillator 902 and the need to synchronize the received radio signal and the output of the oscillator.

FIG. 10 shows a wireless communication system according to the third embodiment of the present invention. A bidirectional wireless communication system is configured by using two sets of the wireless communication systems used in the first (or second) embodiment shown in FIG. 1 (or FIG. 2). For example, assuming that the data optical signal is a data signal on an optical gigabit Ethernet, the user is connected between the transmitting and receiving terminals by an optical fiber, despite the fact that the optical fiber is partially interrupted and wireless. Can be used in the same environment.

FIG. 11 shows a wireless communication system according to the fourth embodiment of the present invention. The transceiver 1101 is shown in FIG.
The electromagnetic wave transmitter shown in FIG. 8 and the electromagnetic wave receiver shown in FIG. 8 are configured using the same antenna 1102. Switching between transmission and reception of wireless signals is performed by switching with a T / R switch 1103. According to this configuration, a module capable of transmitting and receiving can be formed.

FIG. 12 shows a wireless communication system according to a fifth embodiment of the present invention. Unlike the two-way wireless communication system shown in FIG. 10, an asymmetric wireless communication system is configured. Access point 1201 to wireless terminal 12
In the data communication in the downlink direction to 02, the access point 1201 includes the electromagnetic wave transmitter 101 (or 201) shown in FIG.
Has the electromagnetic wave receiver shown in FIG.

On the other hand, data communication in the uplink direction from the wireless terminal 1202 to the access point 1201 uses an existing wireless communication system using a frequency of 5.5 GHz which is a microwave region. The electromagnetic wave received by the access point 1201 is transmitted to the communication protocol converter 1211 and E
The optical signal is converted by the / O converter 1212 into an optical signal conforming to the standard of the optical fiber gigabit Ethernet.

Normally, the communication speed required for data communication from wireless terminal 1202 to access point 1201 is:
It is slower than the communication speed required for data communication from the access point 1201 to the wireless terminal 1202. Therefore,
Even if an existing wireless communication system is used for uplink data communication, there is little problem. According to this configuration, the wireless terminal does not require expensive devices such as an optical modulator and an optical signal generator, so that the price of the wireless terminal can be reduced.

FIG. 13 shows an application example according to the wireless communication system of the third embodiment of the present invention. The first shown in FIG.
FIG. 1 constituted by the wireless communication system of the embodiment of FIG.
A communication network was configured using the wireless communication system of the third embodiment shown in FIG. One base station 1302a
One or a plurality of access points 1301a to 1301f are connected to 1302c. With such a configuration, the optical signal generators 112 to be installed at a plurality of access points are integrated into a base station. As a result, the number of expensive optical signal generators 112 to be installed is reduced, and a millimeter-wave wireless communication network can be constructed at low cost.

FIG. 14 shows an application example according to the wireless communication system of the fifth embodiment of the present invention. A communication network was configured using the wireless communication system according to the fifth embodiment shown in FIG. One or a plurality of access points 1201a to 1201c are connected to one base station 1403, and a plurality of wireless terminals 1 are connected via a wireless line.
202a to 1202c are connected. With such a configuration, information can be distributed from one base station 1403 to a large number of wireless terminals 1202a to 1202c. In addition, by integrating the optical signal generator 112 to be installed at the access point into a base station, a network can be constructed at low cost.

In the above-described embodiment, the amplitude shift keying method is used, but it goes without saying that another modulation method may be used.

[0060]

As described above, according to the present invention,
The data signal is a data optical signal superimposed on the optical signal, and is input to a wireless signal generator or an optical signal generator through an optical fiber. The data optical signal is superimposed on the optical subcarrier signal, then converted into an electromagnetic wave and radiated into the space.
It becomes possible to use a subcarrier signal having a frequency of not less than Hz. Therefore, the frequency of the subcarrier signal is set to 10
By setting the frequency to 0 GHz or more, the bandwidth of the data
z or more.

Further, according to the present invention, since the optical subcarrier signal is modulated by the data optical signal by the optical modulator or the laser generator, it is possible to perform the modulation in the band of 1 GHz or more.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a wireless communication system according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating a wireless communication system according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram illustrating a first example of the electromagnetic wave transmitter in the wireless communication system according to the first embodiment of the present invention.

FIG. 4 is a configuration diagram illustrating a second example of the electromagnetic wave transmitter in the wireless communication system according to the first embodiment of the present invention.

FIG. 5 is a configuration diagram showing a third example of the electromagnetic wave transmitter in the wireless communication system according to the first embodiment of the present invention.

FIG. 6 is a configuration diagram showing a fourth example of the electromagnetic wave transmitter in the wireless communication system according to the first embodiment of the present invention.

FIG. 7 is a configuration diagram illustrating a fifth example of the electromagnetic wave transmitter in the wireless communication system according to the second embodiment of the present invention.

FIG. 8 is a configuration diagram showing a first example of the electromagnetic wave receiver in the wireless communication system according to the first or second embodiment of the present invention.

FIG. 9 is a configuration diagram illustrating a second example of the electromagnetic wave receiver in the wireless communication system according to the first or second embodiment of the present invention.

FIG. 10 is a configuration diagram illustrating a wireless communication system according to a third embodiment of the present invention.

FIG. 11 is a configuration diagram illustrating a wireless communication system according to a fourth embodiment of the present invention.

FIG. 12 is a configuration diagram showing a wireless communication system according to a fifth embodiment of the present invention.

FIG. 13 is a configuration diagram illustrating an application example according to a wireless communication system of a third embodiment of the present invention.

FIG. 14 is a configuration diagram showing an application example according to a wireless communication system of a fifth embodiment of the present invention.

FIG. 15 is a configuration diagram showing a radio transceiver used in a conventional wireless home network.

FIG. 16 is a diagram showing a standard of a cable conventionally used in Ethernet.

[Explanation of symbols]

101, 101a, 101b, 201 Electromagnetic wave transmitter 102, 102a, 102b Electromagnetic wave receiver 111, 121, 211 Optical fiber 112, 702 Optical signal generator 113, 213 Wireless signal generator 114, 124, 214, 1102, 1515, 152
5 Antenna 123 Radio signal receiver 212 Data signal modulated optical signal generator 301, 303, 403, 701, 703 O / E converter 302 Optical modulator 304, 404, 704, 802, 1514, 1524
Amplifier 402 Optical coupler 801 Millimeter wave detector 803 E / O converter 901, 1513, 1523 Mixer 902, 1512, 1522 Oscillator 1101 Transceiver 1103 T / R switch 1201, 1201a to 1201c, 1301a to 13
01f Access point 1202, 1202a to 1202c Wireless terminal 1211 Communication protocol converter 1212 E / O converter 1302a to 1302c, 1402 Base station 1501 Wireless transmitter 1502 Wireless receiver 1511, 1521 High frequency cable

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tadao Nagatsuma 2-3-1 Otemachi, Chiyoda-ku, Tokyo F-term in Nippon Telegraph and Telephone Corporation (reference) 5K002 BA04 BA05 CA14 FA01 5K060 CC02 CC04 EE05 HH01 HH06 HH09

Claims (15)

[Claims] 1. An electromagnetic wave transmitter that inputs a data optical signal on which a data signal is superimposed, converts the data optical signal from an optical fiber, converts the data signal into a radio signal, and radiates the radio signal from a transmitting antenna, generates an optical subcarrier signal serving as a radio carrier. An optical signal generator, a radio signal generator for receiving the optical subcarrier signal and the data optical signal generated by the optical signal generator, and outputting a radio signal on which the data signal is superimposed to the transmitting antenna; An electromagnetic wave transmitter comprising: 2. An electromagnetic wave transmitter for inputting a data optical signal on which a data signal is superimposed, converting the data optical signal into a radio signal, and radiating the data signal from a transmitting antenna. A data signal modulated optical signal generator for superimposing on the optical subcarrier signal, a radio signal on which the optical subcarrier signal on which the data optical signal is superimposed is input from the data signal modulated optical signal generator, and A radio signal generator for outputting a signal to the transmitting antenna. 3. The radio signal generator according to claim 1, further comprising: a first optical signal converting the data optical signal into a first electrical signal.
/ E converter; an optical modulator for modulating the optical subcarrier signal with the first electric signal converted by the first O / E converter; and an optical subcarrier signal modulated by the optical modulator. A second O / E converter for converting the second electric signal into a second electric signal; and a radio signal on which the data signal is superimposed by amplifying the second electric signal converted by the second O / E converter. The electromagnetic wave transmitter according to claim 1, further comprising: an amplifier that outputs a signal. 4. An optical coupler for multiplexing the data optical signal and the optical subcarrier signal to output an optical signal, and for mixing the optical signal output from the optical coupler. A third O / E converter that converts the electric signal into an electric signal, and an amplifier that amplifies the electric signal converted by the third O / E converter and outputs a wireless signal on which the data signal is superimposed. The electromagnetic wave transmitter according to claim 1, comprising: 5. The wireless signal generator and the optical signal generator are constituted by the same module, and an optical signal transmitted in the module is transmitted by an optical fiber or an optical waveguide. The electromagnetic wave transmitter according to claim 3 or 4. 6. The electromagnetic wave according to claim 3, wherein the second O / E converter and the amplifier are configured by the same module, and are connected to the optical modulator by an optical fiber. Transmitter. 7. The electromagnetic wave according to claim 4, wherein the third O / E converter and the amplifier are formed of the same module, and are connected to the optical modulator and an optical fiber. Transmitter. 8. A fourth O / O converter for converting the data optical signal into a fourth electric signal, wherein the data signal modulated optical signal generator converts the data optical signal into a fourth electric signal.
An E-converter, and an optical signal generator that receives the fourth electric signal converted by the fourth O / E converter and generates an optical subcarrier signal on which the data signal is superimposed; A fifth O / E converter that receives the optical subcarrier signal on which the data optical signal is superimposed from the optical signal generator and converts the optical subcarrier signal into a fifth electrical signal; and a fifth O / E converter. The electromagnetic wave transmitter according to claim 2, further comprising: an amplifier that amplifies the fifth electric signal converted by the E converter and outputs a wireless signal on which the data signal is superimposed. 9. The O / E converter according to claim 6, wherein said second O / E converter and said amplifier are replaced with a sixth O / E converter using a single carrier traveling photodiode. The electromagnetic wave transmitter according to claim 3, 5 or 6, wherein an optical subcarrier signal modulated by a modulator is input, and a radio signal on which the data signal is superimposed is output. 10. The optical signal generator according to claim 1, wherein the optical signal generator generates an optical subcarrier signal by multiplying an optical signal generated by an active mode-locked laser, a passive mode-locked laser, or a mode-locked laser. The electromagnetic wave transmitter according to claim 1 or any one of claims 3 to 7. 11. The electromagnetic wave according to claim 1, wherein the optical signal generator generates an optical subcarrier signal by mixing laser oscillation lines of two different wavelengths. Transmitter. 12. An electromagnetic wave receiver which demodulates a radio signal received by a receiving antenna, converts the demodulated data signal into a data optical signal on which a data signal is superimposed, and outputs the data optical signal to an optical fiber. A millimeter-wave detector for detecting a signal and converting the signal to an electric signal; an amplifier for amplifying the electric signal converted by the millimeter-wave detector; and converting the electric signal amplified by the amplifier to an optical signal. And an E / O converter for outputting the data optical signal on which the data signal is superimposed to the optical fiber. 13. The millimeter wave detector includes an oscillator when generating a local oscillation signal, and a mixer that detects the radio signal with the local oscillation signal from the oscillator and converts the radio signal into an electric signal. The electromagnetic wave receiver according to claim 12, wherein 14. An electromagnetic wave transmitter according to claim 1 and an electromagnetic wave receiver according to claim 12 or 13, wherein the transmitting antenna and the receiving antenna are one common antenna. And switching between the output of the electromagnetic wave transmitter and the input of the electromagnetic wave receiver by a T / R switch connected to the shared antenna. 15. A radio terminal having a microwave transmitter and the electromagnetic wave receiver according to claim 12 or 13, an electromagnetic wave transmitter according to any one of claims 1 to 11, a microwave receiver, An access point having a converter for converting an output of the microwave receiver into an optical signal.