JP2009232183A - Transmission apparatus, and transmitting/receiving system using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission apparatus capable of packaging therein a plurality of antenna elements easily. <P>SOLUTION: E/O converters 11-14 convert transmission signals into optical signals OSG1-OSG4 having wavelengths λ<SB>1</SB>-λ<SB>4</SB>different from one another. A photo-coupler 20 superimposes the optical signals OSG1-OSG4 and makes an optical signal OSG incident to an optical fiber 30. A photo-decoupler 40 decouples the optical signal OSG into optical signals OSG1-OSG4 and makes then incident to optical fibers 41-44, respectively. Optical band-pass filters 45-48 cancel noise of the optical signals OSG1-OSG4, respectively, and O/E converters 53-56 convert the optical signals OSG1-OSG4 into electric signals ESG1-ESG4, respectively. On the basis of the electric signals ESG1-ESG4, antenna elements 57-60 radiate radio waves, respectively. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a transmission apparatus and a transmission / reception system using the transmission apparatus, and more particularly to a transmission apparatus that transmits a signal by MIMO (Multi-Input Multi-Output) and a transmission / reception system using the transmission apparatus.

  Conventionally, a transmission / reception system using MIMO is known as a transmission / reception system that transmits information with high efficiency (Non-Patent Document 1). This transmission / reception system using MIMO includes a transmitter having N antenna elements and a receiver having M antenna elements.

The N antenna elements and the M antenna elements are linearly arranged at intervals sufficiently larger than the distance between the N antenna elements and the M antenna elements. Then, the transmitter transmits a transmission signal (radio wave) using N antenna elements. The receiver receives radio waves transmitted from the N antenna elements by M antenna elements, multiplies the received radio waves received by each of the M antenna elements by a weighting factor, and each of the N antenna elements. The signal transmitted from is detected. Then, the receiver acquires a transmission signal based on the detected signal.
Yoshi KARASAWA, “MIMO Propagation Channel Modeling,” IEICE Transactions B Vol. J86-B No. 9 pp. 1706-1720 September 2003

  However, in the conventional transmission / reception system using MIMO, it is necessary to increase the number of antenna elements in the transmitter and the receiver in order to improve the signal transmission speed. In order to exert the above effect, it is necessary to increase the arrangement interval of the antenna elements. As a result, there is a problem that it is difficult to mount a plurality of antenna elements.

  Therefore, the present invention has been made to solve such a problem, and an object of the present invention is to provide a transmission device that can easily mount a plurality of antenna elements.

  Another object of the present invention is to provide a transmission / reception system using a transmission device capable of easily mounting a plurality of antenna elements.

  According to this invention, the transmission device includes a waveguide, a transmitter, first and second signal converters, and a plurality of antenna elements. The waveguide propagates the optical signal. The transmitter generates a transmission signal. The first signal converter converts a transmission signal from the transmitter into a plurality of mutually distinguishable optical signals, and enters the converted plurality of optical signals into the waveguide. The plurality of antenna elements are provided corresponding to the plurality of optical signals. The second signal converter receives a plurality of optical signals propagated in the waveguide, separates the received optical signals from each other, and converts the separated optical signals into a plurality of electrical signals. Then, each electric signal is supplied to the corresponding antenna element.

  Preferably, the first signal converter converts the transmission signal into a plurality of optical signals having mutually different wavelengths, and enters the converted plurality of optical signals into the waveguide as one optical signal. The second signal converter receives the optical signal propagated through the waveguide and separates the received optical signal into a plurality of optical signals.

  Preferably, the first signal converter converts the transmission signal into a plurality of optical signals having the same wavelength, spreads the converted plurality of optical signals with a plurality of mutually different spreading codes, and the plurality of optical signals. Is incident on the waveguide by code division as one optical signal. The second signal converter sequentially receives a plurality of optical signals propagated through the waveguide, converts the received plurality of optical signals into a plurality of electrical signals, and sequentially supplies each electrical signal to the corresponding antenna element. .

  Preferably, the first signal converter generates a plurality of electrical signals by spreading the transmission signal with a plurality of mutually different spreading codes, and the generated plurality of electrical signals are converted into a plurality of optical signals having the same wavelength. The converted plurality of optical signals are incident on the waveguide as one optical signal. The second signal converter receives a plurality of optical signals propagated through the waveguide, despreads the received plurality of optical signals with a plurality of spreading codes, and a plurality of the despread optical signals. The electrical signals are converted into electrical signals and supplied to the corresponding antenna elements.

  According to the invention, the transmission / reception system includes a transmission device and a reception device. The transmission device transmits a transmission signal. The receiving apparatus receives a transmission signal using n (n is an integer of 2 or more) antenna elements. The transmission device includes a waveguide, a transmitter, first and second signal converters, and m (m is an integer of 2 or more) antenna elements. The waveguide propagates the optical signal. The transmitter generates a transmission signal. The first signal converter converts a transmission signal from the transmitter into m optical signals that can be distinguished from each other, and enters the converted m optical signals into the waveguide. The m antenna elements are provided corresponding to m optical signals. The second signal converter receives m optical signals propagated through the waveguide, separates the received optical signals from each other, and converts the separated m optical signals into m electrical signals. And each electric signal is supplied to the corresponding antenna element.

  Preferably, the first signal converter converts the transmission signal into m optical signals having mutually different wavelengths, and enters the converted m optical signals into the waveguide as one optical signal. The second signal converter receives the optical signal propagated through the waveguide and separates the received optical signal into m optical signals.

  Preferably, the first signal converter converts the transmission signal into m optical signals having the same wavelength, and sequentially inputs the converted m optical signals to the waveguide in a time division manner. The second signal converter sequentially receives m optical signals propagated through the waveguide, converts the received m optical signals into m electrical signals, and converts each electrical signal to a corresponding antenna element. Supply sequentially.

  Preferably, the first signal converter converts the transmission signal into a plurality of optical signals having the same wavelength, spreads the converted plurality of optical signals by m different spreading codes, and converts the converted m Each optical signal is incident on the waveguide as a single optical signal by code division. The second signal converter receives m optical signals propagated in the waveguide, despreads the received m optical signals by m spreading codes, and the despread m light signals. The signal is converted into m electrical signals and each electrical signal is supplied to a corresponding antenna element.

  Preferably, the interval between the m antenna elements when the transmission rate of the transmission signal is the first transmission rate is defined as the first interval, and the second transmission in which the transmission rate of the transmission signal is lower than the first transmission rate. When the interval between the m antenna elements before the velocity is the second interval, the m antenna elements are arranged at the second interval.

  In the present invention, the transmission signal is converted into a plurality of mutually identifiable optical signals, the converted plurality of optical signals are propagated through a waveguide, the plurality of optical signals are converted into a plurality of electrical signals, and a plurality of optical signals are converted. Transmit using antenna elements. As a result, an effect equivalent to that of propagating a plurality of optical signals using a plurality of waveguides can be obtained, and the transmitter and the plurality of antenna elements can be connected by almost one waveguide.

  Therefore, according to the present invention, a plurality of antenna elements can be easily mounted.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

[Embodiment 1]
1 is a schematic diagram showing a configuration of a transmission / reception system according to Embodiment 1 of the present invention. Referring to FIG. 1, a transmission / reception system 1000 according to Embodiment 1 of the present invention includes a transmission device 100 and a reception device 200.

  The transmission apparatus 100 includes a transmitter 10, E / O converters 11 to 14, optical fibers 15 to 18, 30, 41 to 44, 49 to 51, an optical coupler 20, an optical separator 40, and an optical fiber. Band pass filters 45-48, O / E converters 53-56, and antenna elements 57-60 are included.

  The optical fiber 15 has one end connected to the E / O converter 11 and the other end connected to the optical coupler 20. The optical fiber 16 has one end connected to the E / O converter 12 and the other end connected to the optical coupler 20. The optical fiber 17 has one end connected to the E / O converter 13 and the other end connected to the optical coupler 20. The optical fiber 18 has one end connected to the E / O converter 14 and the other end connected to the optical coupler 20.

  The optical fiber 30 has one end connected to the optical coupler 20 and the other end connected to the optical separator 40.

  The optical fiber 41 has one end connected to the optical separator 40 and the other end connected to an optical bandpass filter 45. The optical fiber 42 has one end connected to the optical separator 40 and the other end connected to an optical bandpass filter 46. The optical fiber 43 has one end connected to the optical separator 40 and the other end connected to the optical bandpass filter 47. The optical fiber 44 has one end connected to the optical separator 40 and the other end connected to an optical bandpass filter 48.

  The optical fiber 49 has one end connected to the optical bandpass filter 45 and the other end connected to the O / E converter 53. The optical fiber 50 has one end connected to the optical bandpass filter 46 and the other end connected to the O / E converter 54. The optical fiber 51 has one end connected to the optical bandpass filter 47 and the other end connected to the O / E converter 55. The optical fiber 52 has one end connected to the optical bandpass filter 48 and the other end connected to the O / E converter 56. The antenna elements 57 to 60 are connected to the O / E converters 53 to 56, respectively. The

  The transmitter 10 generates a transmission signal and outputs the generated transmission signal to the E / O converters 11 to 14.

E / O converter 11 to 14 converts the transmission signal received from the transmitter 10 from the electric signal into an optical signal OSG1~OSG4 having a wavelength lambda ₁ to [lambda] _4, respectively. The E / O converters 11 to 14 supply the converted optical signals OSG1 to OSG4 to the optical coupler 20 via the optical fibers 15 to 18, respectively.

  The optical coupler 20 receives the optical signals OSG1 to OSG4 via the optical fibers 15 to 18, respectively, and combines the received optical signals OSG1 to OSG4 to combine the optical signals OSG1 to OSG4 to generate the optical signal OSG. Generate. Then, the optical coupler 20 enters the generated optical signal OSG into the optical fiber 30.

  The optical fiber 30 propagates the optical signal OSG from the optical coupler 20 to the optical separator 40. The optical separator 40 separates the optical signal OSG into optical signals OSG1 to OSG4. Then, the optical separator 40 supplies the optical signal OSG1 to the optical bandpass filter 45 via the optical fiber 41. The optical separator 40 supplies the optical signal OSG2 to the optical bandpass filter 46 via the optical fiber 42. Further, the optical separator 40 supplies the optical signal OSG3 to the optical bandpass filter 47 via the optical fiber 43. Further, the optical separator 40 supplies the optical signal OSG 4 to the optical bandpass filter 48 via the optical fiber 44.

Optical bandpass filter 45 receives the optical signal OSG1 through the optical fiber 41 to remove the noise which is a component other than the wavelength lambda ₁ of the optical signal OSG1 thereof received, an optical fiber an optical signal OSG1 removal of the noise Supplied to the O / E converter 53 via 49.

Optical bandpass filter 46 receives the optical signal OSG2 through the optical fiber 42 to remove the noise which is a component other than the wavelength lambda ₂ of the optical signal OSG2 thereof received, an optical fiber an optical signal OSG2 removal of the noise 50 to the O / E converter 54.

Optical band pass filter 47 receives the optical signal OSG3 through the optical fiber 43 to remove the noise which is a component other than the wavelength lambda ₃ of the optical signal OSG3 thereof received, an optical fiber an optical signal OSG3 removal of the noise 51 to the O / E converter 55.

Optical bandpass filter 48 receives the optical signal OSG4 through the optical fiber 44 to remove the noise which is a component other than the wavelength lambda ₄ of the optical signal OSG4 thereof received, an optical fiber an optical signal OSG4 removal of the noise 52 to the O / E converter 56.

  The optical fibers 49 to 52 propagate the optical signals OSG1 to OSG4 from the optical bandpass filters 45 to 48 to the O / E converters 53 to 56, respectively.

  The O / E converter 53 receives the optical signal OSG1 through the optical fiber 49, converts the received optical signal OSG1 into an electric signal ESG1, and supplies the converted electric signal ESG1 to the antenna element 57.

  The O / E converter 54 receives the optical signal OSG2 through the optical fiber 50, converts the received optical signal OSG2 into an electric signal ESG2, and supplies the converted electric signal ESG2 to the antenna element 58.

  The O / E converter 55 receives the optical signal OSG3 via the optical fiber 51, converts the received optical signal OSG3 into an electric signal ESG3, and supplies the converted electric signal ESG3 to the antenna element 59.

  The O / E converter 56 receives the optical signal OSG4 through the optical fiber 52, converts the received optical signal OSG4 into an electric signal ESG4, and supplies the converted electric signal ESG4 to the antenna element 60.

  The antenna elements 57 to 60 radiate radio waves wv1 to wv4 based on the electric signals ESG1 to ESG4, respectively.

  The receiving device 200 includes antenna elements 201 to 204 and a receiver 210. The antenna elements 201 to 204 receive the radio waves radiated from the antenna elements 57 to 60 and supply the received radio waves to the receiver 210.

  The receiver 210 performs reception processing by a known method based on the four radio waves received from the antenna elements 201 to 204, and acquires a reception signal.

  FIG. 2 is a diagram for explaining a method of experimenting a change in communication characteristics depending on the arrangement interval of a plurality of antenna elements of the transmission apparatus 100. Referring to FIG. 2, personal computer PC1 is connected to access point AP via Ethernet (registered trademark) cable Eth.

  The access point AP is connected to the antennas ANT1 to ANT3. The antennas ANT1 to ANT3 are arranged in a straight line. The personal computer PC2 includes antennas ANT4 to ANT6.

  And the communication characteristic of radio | wireless communication was measured by changing the space | interval d between the antennas ANT1-ANT3 and the distance r between the antennas ANT1-ANT3 and the antennas ANT4-ANT6.

  Table 1 shows the communication specifications used in the experiment.

  Further, Table 2 shows the communication protocol, distance r, and interval d in each experiment.

  FIG. 3 is a diagram illustrating the relationship between the reception rate and the transmission rate. In FIG. 3, the vertical axis represents the reception rate, and the horizontal axis represents the transmission rate. Curves k1 to k4 are respectively shown as experiment ID. 1 to ID. 4 shows the relationship between the reception rate and the transmission rate.

  Experiment ID. 1, IEEE 802.11g is used, so that the reception rate saturates at the upper limit speed of IEEE 802.11g as the transmission rate increases (see curve k1).

  Experiment ID. 2, ID. 4, the reception rate increases almost linearly with increasing transmission rate (see curves k2 and k4). Experiment ID. 3, the reception rate rises almost in proportion to the transmission rate until the transmission rate reaches 60 Mbps, and saturates when the transmission rate becomes 60 Mbps or more (see curve k3).

  As a result, in the case of using IEEE802.11n, if the distance r is changed from 1 m to 9 m while the distance d between the antennas ANT1 to ANT3 is maintained at 0.05 m, the reception rate becomes higher than 60 Mbps. (See curves k2 and k3).

  However, the reception rate increases linearly as the transmission rate increases for transmission rates of 60 Mbps or less, and is almost the same as the characteristics when the interval between the antennas ANT1 to ANT3 is set to 2 m. (Refer to the curves k3 and k4). Even if the antennas ANT1 to ANT3 are centrally arranged at intervals of 0.05 m, wireless communication can be performed while suppressing deterioration in communication quality (see curves k3 and k4).

  Next, evaluation by simulation will be described. FIG. 4 is a diagram illustrating an arrangement pattern of transmitters and receivers used in the simulation. Referring to FIG. 4, pattern a is a pattern with four reception antennas and one transmission antenna. Pattern b is a pattern in which four transmission antennas are arranged in a concentrated manner. Furthermore, the pattern c is a pattern in which transmission antennas are spatially dispersed.

  Further, Table 3 shows parameters used for the simulation.

  FIG. 5 is a diagram showing a simulation result. In FIG. 5, the vertical axis represents the transmission rate of a plurality of terminal devices divided by the frequency bandwidth (= corresponding to the transmission rate), and the horizontal axis represents the ratio of the received signal and noise energy at the receiving antenna. .

  Curves k5 to k7 indicate the characteristics of the pattern a, the pattern b, and the pattern c, respectively.

  Referring to FIG. 5, in the case of pattern c, since the transmission antennas are distributed, the transmission rate rises and saturates as the received signal / noise energy ratio increases (see curve k7). In the case of pattern b, the decrease from the transmission speed in pattern c is small despite the concentrated transmission antennas (see curves k6 and k7).

  On the other hand, in the case of pattern a, the decrease from the transmission rate in pattern c is large (see curves k5 and k7).

  In this way, if a plurality of antennas are distributed and distributed, the communication characteristics are the best (see curve k7), and even if a plurality of antennas are arranged in a concentrated manner, the reduction in communication characteristics is small (see curves k6 and k7). ) In the transmission / reception system 1000, the antenna elements 57 to 60 of the transmission device 100 are arranged in a distributed or concentrated manner.

  Even if the antenna elements 57 to 60 are distributed, most of the optical fibers arranged between the E / O converters 11 to 14 and the antenna elements 57 to 60 are occupied by the single optical fiber 30. Thus, unlike the case where a plurality of antenna elements are distributedly arranged, it is not necessary to arrange many cables between the transmitter and the plurality of antenna elements, and the plurality of antenna elements can be easily mounted.

  As described above, the transmission / reception system 1000 has a first feature that the E / O converters 11 to 14 and the antenna elements 57 to 60 in the transmission apparatus 100 are coupled by the single optical fiber 30. .

In addition, converted by the E / O converter 11 to 14 into an optical signal OSG1~OSG4 having different wavelengths lambda ₁ to [lambda] ₄ to each other transmit signal, an optical signal OSG superimposes the optical signal OSG1~OSG4 that the conversion Since the optical signal OSG that has entered the optical fiber 30 and propagated through the optical fiber 30 is separated into optical signals OSG1 to OSG4 by the optical separator 40 and led to the antenna elements 57 to 60, substantially, E / O conversion is performed. This is equivalent to the propagation of an optical signal using four optical fibers from the devices 11 to 14 to the antenna elements 57 to 60, and even if the antenna elements 57 to 60 are centrally arranged, the deterioration of the communication characteristics is reduced.

Thus, in the first embodiment, the optical signal OSG1～OSG4 converted into an optical signal OSG1～OSG4, that the conversion having a wavelength lambda ₁ to [lambda] ₄ mutually different transmission signals by the E / O converter 11 to 14 The second feature is that the optical signal OSG is incident on the optical fiber 30 in a superimposed manner.

  The transmission rate when the antenna elements 57 to 60 are distributed (see curve k7 in FIG. 5) is the first transmission rate, and the interval when the antenna elements 57 to 60 are distributed (= 2 m, ID. 4) is defined as the first interval, the antenna elements 57 to 60 are spaced apart from each other so that a second transmission rate lower than the first transmission rate (see curve k6 in FIG. 5) is obtained. The antenna elements 57 to 60 are arranged in a concentrated manner at a narrower second interval.

  In the transmission / reception system 1000, when transmitting a signal from the transmitter 10 to the receiver 210, the transmitter 10 performs E / O conversion on the transmission signals s1, s2, s3, s4, s5, s7, and s8 as follows. To the devices 11-14.

  That is, the transmitter 10 outputs the transmission signals s1, s2, s3, and s4 to the E / O converters 11 to 14, respectively, and then transmits the transmission signals s5, s6, s7, and s8 to the E / O converters 11 to 11, respectively. 14 to output. Thus, the transmitter 10 outputs the transmission signal to the E / O converters 11 to 14 so as to transmit the transmission signal in parallel.

  Then, the E / O converter 11 sequentially converts the signals s1 and s5 from the electric signal to the optical signal OSG1 and guides it to the optical coupler 20. In addition, the E / O converter 12 sequentially converts the signals s2 and s6 from an electric signal to an optical signal OSG2, and guides it to the optical coupler 20. Further, the E / O converter 13 sequentially converts the signals s3 and s7 from an electric signal to an optical signal OSG3 and guides it to the optical coupler 20. Further, the E / O converter 14 sequentially converts the signals s4 and s8 from an electric signal to an optical signal OSG4 and guides it to the optical coupler 20.

  The optical coupler 20 receives the optical signals OSG1 to OSG4 via the optical fibers 15 to 18, respectively, and superimposes the received optical signals OSG1 to OSG4 to make the optical signal OSG enter the optical fiber 30.

  The optical fiber 30 propagates the optical signal OSG from the optical coupler 20 to the optical separator 40, and the optical separator 40 separates the optical signal OSG into optical signals OSG1 to OSG4. Then, the optical separator 40 outputs the separated optical signal OSG1 to the optical bandpass filter 45 via the optical fiber 41, and outputs the separated optical signal OSG2 to the optical bandpass filter 46 via the optical fiber 42. The separated optical signal OSG3 is output to the optical bandpass filter 47 via the optical fiber 43, and the separated optical signal OSG4 is output to the optical bandpass filter 48 via the optical fiber 44.

  The optical bandpass filter 45 removes the optical signals OSG 2, OSG 3, OSG 4 other than the optical signal OSG 1, and outputs the optical signal OSG 1 to the O / E converter 53 via the optical fiber 49. The optical bandpass filter 46 removes the optical signals OSG 1, OSG 3, OSG 4 other than the optical signal OSG 2, and outputs the optical signal OSG 2 to the O / E converter 54 via the optical fiber 50. Further, the optical bandpass filter 47 removes the optical signals OSG 1, OSG 2, OSG 4 other than the optical signal OSG 3 and outputs the optical signal OSG 3 to the O / E converter 55 via the optical fiber 51. Further, the optical bandpass filter 48 removes the optical signals OSG 1, OSG 2, OSG 3 other than the optical signal OSG 4 and outputs the optical signal OSG 4 to the O / E converter 56 via the optical fiber 52.

  The O / E converter 53 converts the optical signal OSG1 into an electric signal ESG1 and outputs it to the antenna element 57. The O / E converter 54 converts the optical signal OSG2 into an electric signal ESG2 and outputs it to the antenna element 58. Further, the O / E converter 55 converts the optical signal OSG3 into an electric signal ESG3 and outputs it to the antenna element 59. Further, the O / E converter 56 converts the optical signal OSG4 into an electric signal ESG4 and outputs it to the antenna element 60.

  And the antenna elements 57-60 radiate | emit radio waves wv1-wv4 based on the electric signals ESG1-ESG4, respectively.

  The antenna elements 201 to 204 of the receiving device 200 receive the radio waves radiated from the antenna elements 57 to 60 of the transmitting device 100 and output the received radio waves to the receiver 210. The receiver 210 performs a reception process based on the radio waves received from the antenna elements 201 to 204 and receives the transmission signal transmitted from the transmitter 10.

  According to the first embodiment, the transmission signal is converted into optical signals OSG1 to OSG4 having different wavelengths, and the converted optical signals OSG1 to OSG4 are superimposed so that the optical signal OSG enters the single optical fiber 30. Thus, the transmitter 10 and the antenna elements 57 to 60 can be connected by almost one optical fiber 30 and a plurality of antenna elements can be easily mounted.

  Further, since the transmission signal is converted into optical signals OSG1 to OSG4 having different wavelengths and propagated through one optical fiber 30, the optical signals OSG1 to OSG4 are transmitted from the transmitter 10 to the antenna element 57 using four optical fibers. An effect equivalent to that of propagation up to ˜60 can be obtained, and even if the antenna elements 57 to 60 are arranged in a concentrated manner, deterioration of communication characteristics can be suppressed to a minimum.

  Furthermore, since the signal is propagated from the transmitter 10 to the antenna elements 57 to 60 by the single optical fiber 30, the communication band can be widened.

[Embodiment 2]
FIG. 6 is a schematic diagram showing a configuration of a transmission / reception system according to the second embodiment. Referring to FIG. 6, transmission / reception system 1000A according to Embodiment 2 is the same as transmission / reception system 1000 except that transmission apparatus 100 of transmission / reception system 1000 shown in FIG.

  The transmission device 100A deletes the optical fibers 49 to 52 of the transmission device 100 shown in FIG. 1, replaces the E / O converters 11 to 14 with the E / O converters 11A to 14A, and replaces the optical coupler 20 with an optical switch. Instead of 20A, the optical separator 40 is replaced with the optical switch 40A, the optical bandpass filters 45 to 48 are replaced with the bandpass filters 61 to 64, and the others are the same as those of the transmission device 100.

  The optical switch 20 </ b> A is disposed between the optical fibers 15 to 18 and the optical fiber 30 and is connected to one end of the optical fiber 30. The optical switch 40 </ b> A is disposed between the optical fiber 30 and the optical fibers 41 to 44 and connected to the other end of the optical fiber 30.

  The bandpass filter 61 is disposed between the O / E converter 53 and the antenna element 57, and the bandpass filter 62 is disposed between the O / E converter 54 and the antenna element 58, and the bandpass filter 63. Is disposed between the O / E converter 55 and the antenna element 59, and the band pass filter 64 is disposed between the O / E converter 56 and the antenna element 60.

  In the transmission device 100A, the O / E converters 53 to 56 are connected to the other ends of the optical fibers 41 to 44, respectively.

  Each of the E / O converters 11A to 14A converts the transmission signal into optical signals OSG1 to OSG4 having the same wavelength, and enters the converted optical signals OSG1 to OSG4 into the optical fibers 15 to 18, respectively.

  The optical switch 20A guides the optical signals OSG1 to OSG4 propagated through the optical fibers 15 to 18 to the optical fiber 30 in a time division manner.

  The optical switch 40A guides the optical signals OSG1 to OSG4 propagated through the optical fiber 30 into the optical fibers 41 to 44, respectively, in a time division manner.

  The band-pass filter 61 removes noise from the electrical signal ESG1 received from the O / E converter 53 and connects a plurality of electrical signals ESG1 sequentially received from the O / E converter 53 to output to the antenna element 57. .

  The band-pass filter 62 removes noise from the electrical signal ESG2 received from the O / E converter 54 and connects a plurality of electrical signals ESG2 sequentially received from the O / E converter 54 to output to the antenna element 58. .

  The bandpass filter 63 removes noise from the electrical signal ESG3 received from the O / E converter 55 and connects the plurality of electrical signals ESG3 sequentially received from the O / E converter 55 to output to the antenna element 59. .

  The band-pass filter 64 removes noise from the electrical signal ESG4 received from the O / E converter 56 and connects a plurality of electrical signals ESG4 sequentially received from the O / E converter 56 to output to the antenna element 60. .

  The order in which the optical switch 20A selects the optical signals OSG1 to OSG4 and the order in which the optical switch 40A guides the optical signals OSG1 to OSG4 propagated through the optical fiber 30 to the optical fibers 41 to 44 are the optical fibers 15 to 18. The optical signals OSG1 to OSG4 propagated through the inside are determined to enter the optical fibers 41 to 44, respectively, and are set in advance in the optical switches 20A and 40A.

  In the transmitting device 100A, the optical signals OSG1 to OSG4 generated by the E / O converters 11A to 14A are temporally separated by the optical switch 20A and propagated in one optical fiber 30, and the optical fiber 30 is propagated through the optical fiber 30. Since the propagated optical signals OSG1 to OSG4 are separated into the antenna elements 57 to 60 by the optical switch 40A, the optical signals OSG1 to OSG4 are separated between the transmitter 10 and the antenna elements 57 to 60 by four optical fibers. This is equivalent to the propagation, and the same effect as in the first embodiment can be obtained.

  A communication operation in the transmission / reception system 1000A will be described. The transmitter 10 outputs the transmission signals s1, s2, s3, and s4 to the E / O converters 11A to 14A, and then transmits the transmission signals s5, s6, s7, and s8 to the E / O converters 11A to 14A, respectively. Output.

  Then, the E / O converter 11A sequentially converts the signals s1 and s5 from an electrical signal into an optical signal OSG1, and enters the optical fiber 15. Further, the E / O converter 12A sequentially converts the signals s2 and s6 from an electric signal to an optical signal OSG2, and enters the optical fiber 16. Further, the E / O converter 13A sequentially converts the signals s3 and s7 from an electrical signal into an optical signal OSG3 and enters the optical fiber 17. Further, the E / O converter 14A sequentially converts the signals s4 and s8 from an electric signal to an optical signal OSG4 and enters the optical fiber 18.

  The optical switch 20A selects the optical signals OSG1 to OSG4 via the optical fibers 15 to 18 in the order of the optical signal OSG1, the optical signal OSG2, the optical signal OSG3, and the optical signal OSG4, for example, and the selected optical signal The OSG1, the optical signal OSG2, the optical signal OSG3, and the optical signal OSG4 are sequentially incident on the optical fiber 30.

  Then, the optical fiber 30 sequentially propagates the optical signal OSG1, the optical signal OSG2, the optical signal OSG3, and the optical signal OSG4 from the optical switch 20A to the optical switch 40A. The optical switch 40A sequentially selects the optical signal OSG1, the optical signal OSG2, the optical signal OSG3, and the optical signal OSG4, and the selected optical signal OSG1, optical signal OSG2, optical signal OSG3, and optical signal OSG4 are optical fibers 41 to 44, respectively. Sequentially incident on.

  The O / E converter 53 converts the optical signal OSG1 into an electrical signal ESG1 and outputs it to the bandpass filter 61. The O / E converter 54 converts the optical signal OSG2 into an electric signal ESG2 and outputs it to the bandpass filter 62. Further, the O / E converter 55 converts the optical signal OSG3 into an electric signal ESG3 and outputs it to the bandpass filter 63. Further, the O / E converter 56 converts the optical signal OSG4 into an electric signal ESG4 and outputs it to the bandpass filter 64.

  The band pass filter 61 removes noise from the electrical signal ESG1 and connects to the antenna element 57 for output. Further, the band pass filter 62 removes noise of the electric signal ESG 2 and connects to the antenna element 58 for output. Further, the bandpass filter 63 removes noise from the electrical signal ESG3 and connects to the antenna element 59 for output. Further, the band pass filter 64 removes noise from the electrical signal ESG4 and connects to the antenna element 60 for output.

  And the antenna elements 57-60 radiate | emit radio waves wv1-wv4 based on the electric signals ESG1-ESG4, respectively.

  The antenna elements 201 to 204 of the receiving apparatus 200 receive the radio waves radiated from the antenna elements 57 to 60 of the transmitting apparatus 100 </ b> A and output the received radio waves to the receiver 210. The receiver 210 performs a reception process based on the radio waves received from the antenna elements 201 to 204 and receives the transmission signal transmitted from the transmitter 10.

  According to the second embodiment, the transmission signal is converted into optical signals OSG1 to OSG4 having the same wavelength, and the converted optical signals OSG1 to OSG4 are incident on one optical fiber 30 in a time-sharing manner to be antenna elements 57-60. Therefore, the transmitter 10 and the antenna elements 57 to 60 can be connected by almost one optical fiber 30, and a plurality of antenna elements can be easily mounted.

  Further, since the optical signals OSG1 to OSG4 are propagated through the one optical fiber 30 in a time division manner, the optical signals OSG1 to OSG4 are propagated from the transmitter 10 to the antenna elements 57 to 60 using four optical fibers. The effect equivalent to is obtained, and even if the antenna elements 57 to 60 are arranged in a concentrated manner, the deterioration of the communication characteristics can be suppressed to the minimum.

  Furthermore, since the signal is propagated from the transmitter 10 to the antenna elements 57 to 60 by the single optical fiber 30, the communication band can be widened.

  Others are the same as in the first embodiment.

[Embodiment 3]
FIG. 7 is a schematic diagram showing a configuration of a transmission / reception system according to the third embodiment. Referring to FIG. 7, transmission / reception system 1000B according to the third embodiment is the same as transmission / reception system 1000 except that transmission apparatus 100 of transmission / reception system 1000 shown in FIG.

  Transmitting apparatus 100B replaces E / O converters 11-14 of transmitting apparatus 100 shown in FIG. 1 with E / O converters 11A-14A, respectively, and replaces optical bandpass filters 45-48 with encoders 73-76, respectively. , Optical fibers 65 to 68 and encoders 69 to 72 are added, and the others are the same as those of the transmission device 100.

  The optical fiber 65 has one end connected to the E / O converter 11 </ b> A and the other end connected to the encoder 69. The optical fiber 66 has one end connected to the E / O converter 12 </ b> A and the other end connected to the encoder 70. The optical fiber 67 has one end connected to the E / O converter 13 </ b> A and the other end connected to the encoder 71. The optical fiber 68 has one end connected to the E / O converter 14 </ b> A and the other end connected to the encoder 72.

  The encoder 69 is disposed between the E / O converter 11 </ b> A and the optical fiber 15. The encoder 70 is disposed between the E / O converter 12 </ b> A and the optical fiber 16. The encoder 71 is disposed between the E / O converter 13 </ b> A and the optical fiber 17. The encoder 72 is disposed between the E / O converter 14 </ b> A and the optical fiber 18.

  The encoder 73 is disposed between the optical fiber 41 and the optical fiber 49. The encoder 74 is disposed between the optical fiber 42 and the optical fiber 50. The encoder 75 is disposed between the optical fiber 43 and the optical fiber 51. The encoder 76 is disposed between the optical fiber 44 and the optical fiber 52.

  The band pass filter 61 is disposed between the O / E converter 53 and the antenna element 57. The band pass filter 62 is disposed between the O / E converter 54 and the antenna element 58. The band pass filter 63 is disposed between the O / E converter 55 and the antenna element 59. The band pass filter 64 is disposed between the O / E converter 56 and the antenna element 60.

  Each of the E / O converters 11A to 14A converts the transmission signal from the transmitter 10 into optical signals OSG1 to OSG4 having the same wavelength, and the converted optical signals OSG1 to OSG4 via optical fibers 65 to 68, respectively. And output to the encoders 69-72.

  The optical fibers 65 to 68 propagate the optical signals OSG1 to OSG4 from the E / O converters 11A to 14A to the encoders 69 to 72, respectively.

  The encoder 69 spreads the optical signal OSG1 with the spread code c1 and makes the spread optical signal OSG1_c incident on the optical fiber 15. The encoder 70 spreads the optical signal OSG2 by the spreading code c2, and enters the spread optical signal OSG2_c into the optical fiber 16. The encoder 71 diffuses the optical signal OSG3 with the spreading code c3 and makes the spread optical signal OSG3_c incident on the optical fiber 17. The encoder 72 spreads the optical signal OSG4 with the spreading code c4 and makes the spread optical signal OSG4_c incident on the optical fiber 18.

  The encoder 73 despreads the optical signal OSG1_c propagated through the optical fiber 41 into the spread code c1, and outputs the despread optical signal OSG1 to the O / E converter 53 via the optical fiber 49.

  The encoder 74 despreads the optical signal OSG2_c propagated through the optical fiber 42 into the spread code c2, and outputs the despread optical signal OSG2 to the O / E converter 54 via the optical fiber 50.

  The encoder 75 despreads the optical signal OSG3_c propagated through the optical fiber 43 into the spread code c3 and outputs the despread optical signal OSG3 to the O / E converter 55 via the optical fiber 51.

  The encoder 76 despreads the optical signal OSG4_c propagated through the optical fiber 44 into the spread code c4 and outputs the despread optical signal OSG4 to the O / E converter 56 via the optical fiber 52.

  The bandpass filters 61 to 64 perform the same functions as those described in the second embodiment.

  In the transmission device 100B, the optical coupler 20 superimposes the optical signals OSG1_c to OSG4_c and makes the optical signal OSG_c enter the optical fiber 30. The optical separator 40 separates the optical signal OSG_c propagated through the optical fiber 30 into optical signals OSG1_c to OSG4_c, and enters the separated optical signals OSG1_c to OSG4_c into the optical fibers 41 to 44, respectively.

  In the transmission device 100B, the optical signals OSG1 to OSG4 generated by the E / O converters 11A to 14A are converted into optical signals OSG1_c to OSG4_c by mutually different spreading codes c1 to c4, and the converted optical signals OSG1_c to OSG4_c are converted. And the optical signal OSG_c propagates in one optical fiber 30, and the optical signal OSG_c propagated in the optical fiber 30 is separated into optical signals OSG1_c to OSG4_c by the optical separator 40. This is equivalent to propagating the optical signals OSG1 to OSG4 with the four optical fibers between the elements 57 to 60, and the same effect as in the first embodiment can be obtained.

  A communication operation in the transmission / reception system 1000B will be described. The transmitter 10 outputs the transmission signals s1, s2, s3, and s4 to the E / O converters 11A to 14A, and then transmits the transmission signals s5, s6, s7, and s8 to the E / O converters 11A to 14A, respectively. Output.

  Then, the E / O converter 11A sequentially converts the signals s1 and s5 from an electric signal to an optical signal OSG1, and outputs the signal to the encoder 69. In addition, the E / O converter 12A sequentially converts the signals s2 and s6 from an electric signal to an optical signal OSG2, and outputs the signal to the encoder 70. Further, the E / O converter 13A sequentially converts the signals s3 and s7 from the electric signal to the optical signal OSG3 and outputs the signal to the encoder 71. Further, the E / O converter 14 a sequentially converts the signals s 4 and s 8 from an electric signal to an optical signal OSG 4 and outputs the converted signal to the encoder 72.

  The encoder 69 spreads the optical signal OSG1 with the spread code c1 and makes the spread optical signal OSG1_c incident on the optical fiber 15. The encoder 70 spreads the optical signal OSG2 by the spreading code c2, and enters the spread optical signal OSG2_c into the optical fiber 16. The encoder 71 diffuses the optical signal OSG3 with the spreading code c3 and makes the spread optical signal OSG3_c incident on the optical fiber 17. The encoder 72 spreads the optical signal OSG4 with the spreading code c4 and makes the spread optical signal OSG4_c incident on the optical fiber 18.

  The optical coupler 20 receives the optical signals OSG1_c to OSG4_c via the optical fibers 15 to 18, respectively, and superimposes the received optical signals OSG1_c to OSG4_c to make the optical signal OSG_c enter the optical fiber 30.

  The optical fiber 30 propagates the optical signal OSG_c from the optical coupler 20 to the optical separator 40, and the optical separator 40 separates the optical signal OSG_c into optical signals OSG1_c to OSG4_c. Then, the optical separator 40 outputs the separated optical signal OSG1_c to the encoder 73 via the optical fiber 41, and outputs the separated optical signal OSG2_c to the encoder 74 via the optical fiber 42. The optical signal OSG3_c is output to the encoder 75 via the optical fiber 43, and the separated optical signal OSG4_c is output to the encoder 76 via the optical fiber 44.

  The encoder 73 despreads the optical signal OSG1_c with the spread code c1 and outputs the despread optical signal OSG1 to the O / E converter 53 via the optical fiber 49. The encoder 74 despreads the optical signal OSG2_c with the spread code c2 and outputs the despread optical signal OSG2 to the O / E converter 54 via the optical fiber 50. Further, the encoder 75 despreads the optical signal OSG3_c with the spread code c3 and outputs the despread optical signal OSG3 to the O / E converter 55 via the optical fiber 51. Further, the encoder 76 despreads the optical signal OSG4_c with the spread code c4 and outputs the despread optical signal OSG4 to the O / E converter 56 via the optical fiber 52.

  The O / E converter 53 converts the optical signal OSG1 into an electrical signal ESG1 and outputs it to the bandpass filter 61. The O / E converter 54 converts the optical signal OSG2 into an electric signal ESG2 and outputs it to the bandpass filter 62. Further, the O / E converter 55 converts the optical signal OSG3 into an electric signal ESG3 and outputs it to the bandpass filter 63. Further, the O / E converter 56 converts the optical signal OSG4 into an electric signal ESG4 and outputs it to the bandpass filter 64.

  The band pass filter 61 removes noise from the electrical signal ESG1 and connects to the antenna element 57 for output. Further, the band pass filter 62 removes noise of the electric signal ESG 2 and connects to the antenna element 58 for output. Further, the bandpass filter 63 removes noise from the electrical signal ESG3 and connects to the antenna element 59 for output. Further, the band pass filter 64 removes noise from the electrical signal ESG4 and connects to the antenna element 60 for output.

  And the antenna elements 57-60 radiate | emit radio waves wv1-wv4 based on the electric signals ESG1-ESG4, respectively.

  The antenna elements 201 to 204 of the receiving apparatus 200 receive radio waves radiated from the antenna elements 57 to 60 of the transmitting apparatus 100B, and output the received radio waves to the receiver 210. The receiver 210 performs a reception process based on the radio waves received from the antenna elements 201 to 204 and receives the transmission signal transmitted from the transmitter 10.

  According to the third embodiment, transmission signals are converted into optical signals OSG1_c to OSG4_c by mutually different spreading codes c1 to c4, and the converted optical signals OSG1_c to OSG4_c are superimposed to make the optical signal OSG_c a single optical fiber. Therefore, the transmitter 10 and the antenna elements 57-60 can be connected by almost one optical fiber 30, and a plurality of antenna elements can be easily mounted.

  Further, since the transmission signals are converted into optical signals OSG1_c to OSG4_c by different spreading codes c1 to c4 and propagated through one optical fiber 30, the optical signals OSG1_c to OSG4_c are transmitted using four optical fibers. An effect equivalent to that transmitted from the device 10 to the antenna elements 57 to 60 can be obtained, and even if the antenna elements 57 to 60 are arranged in a concentrated manner, a decrease in communication characteristics can be suppressed to a minimum.

  Furthermore, since the signal is propagated from the transmitter 10 to the antenna elements 57 to 60 by the single optical fiber 30, the communication band can be widened.

  Others are the same as in the first embodiment.

  As described above, in the first embodiment, the transmission signal is converted into a plurality of optical signals having different wavelengths and propagated through one optical fiber 30, and in the second embodiment, the transmission signal is time-divisionally divided. In the third embodiment, the transmission signal is converted into a plurality of optical signals by using different spreading codes and is transmitted through the single optical fiber 30. Propagated.

  Therefore, in the present invention, the transmission device only needs to include a signal converter that converts a transmission signal into a plurality of optical signals that can be distinguished from each other.

  Further, in the above description, the transmission devices 100, 100A, and 100B are provided with the four antenna elements 57 to 60, and the reception device 200 is provided with the four antenna elements 201 to 204. Not limited to this, the transmission devices 100, 100A, 100B and the reception device 200 generally only need to include a plurality of antenna elements. The number of antenna elements of transmitting apparatuses 100, 100A, and 100B may be the same as or different from the number of antenna elements of receiving apparatus 200.

  In the present invention, the optical fiber 30 constitutes a “waveguide”.

  In the present invention, the E / O converters 11 to 14 and the optical coupler 20 constitute a “first signal converter”, and include an optical separator 40, optical bandpass filters 45 to 48, and an O / E. The converters 53 to 56 constitute a “second signal converter”.

  Furthermore, in the present invention, the E / O converters 11A to 14A and the optical switch 20A constitute a “first signal converter”, and the optical switch 40A and the O / E converters 53 to 56 are “second signal converters”. Of the signal converter ”.

  Further, in the present invention, the E / O converters 11A to 14A, the encoders 69 to 72, and the optical coupler 20 constitute a “first signal converter”, and the optical separator 40 and the encoders 73 to 76. The O / E converters 53 to 56 constitute a “second signal converter”.

  Further, in the present invention, the antenna elements 57 to 60 constitute “m (m is an integer of 2 or more) antenna elements”, and the antenna elements 201 to 204 are “n (n is an integer of 2 or more)”. Individual antenna elements ”.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  The present invention is applied to a transmission apparatus capable of easily mounting a plurality of antenna elements. In addition, the present invention is applied to a transmission / reception system using a transmission apparatus that can easily mount a plurality of antenna elements.

It is the schematic which shows the structure of the transmission / reception system by Embodiment 1 of this invention. It is a figure for demonstrating the method to experiment the change of the communication characteristic by the arrangement | positioning space | interval of the some antenna element of a transmitter. It is a figure which shows the relationship between a reception rate and a transmission rate. It is a figure which shows the arrangement pattern of the transmitter and receiver which were used for simulation. It is a figure which shows a simulation result. It is the schematic which shows the structure of the transmission / reception system by Embodiment 2. FIG. FIG. 10 is a schematic diagram showing a configuration of a transmission / reception system according to Embodiment 3.

Explanation of symbols

  10 transmitter, 11-14, 11A-14A E / O converter, 15-18, 30, 41-44, 49-52, 65-68 optical fiber, 20 optical coupler, 20A, 40A optical switch, 40 light Separator, 45-48 optical bandpass filter, 53-56 O / E converter, 57-60, 201-204 antenna element, 61-64 bandpass filter, 69-76 encoder, 100, 100A, 100B transmitter 200 receiver, 210 receiver, 1000, 1000A, 1000B transmission / reception system.

Claims (9)

A waveguide for propagating an optical signal;
A transmitter for generating a transmission signal;
A first signal converter that converts the transmission signals from the transmitter into a plurality of mutually distinguishable optical signals, and enters the converted optical signals into the waveguide;
A plurality of antenna elements provided corresponding to the plurality of optical signals;
The optical signals propagated in the waveguide are received, the received optical signals are separated from each other, and the separated optical signals are converted into a plurality of electrical signals to correspond to the respective electrical signals. And a second signal converter for supplying to the antenna element. The first signal converter converts the transmission signal into a plurality of optical signals having mutually different wavelengths, and enters the converted plurality of optical signals as one optical signal into the waveguide,
2. The transmission device according to claim 1, wherein the second signal converter receives an optical signal propagated through the waveguide and separates the received optical signal into the plurality of optical signals. The first signal converter converts the transmission signal into a plurality of optical signals having the same wavelength, and sequentially enters the converted plurality of optical signals into the waveguide in a time-sharing manner,
The second signal converter sequentially receives a plurality of optical signals propagated through the waveguide, converts the received plurality of optical signals into a plurality of electrical signals, and sequentially converts each electrical signal to a corresponding antenna element. The transmission device according to claim 1, wherein the transmission device is supplied. The first signal converter converts the transmission signal into a plurality of optical signals having the same wavelength, spreads the converted plurality of optical signals by a plurality of mutually different spreading codes, and converts the plurality of optical signals to each other. Incident into the waveguide by code division as one optical signal,
The second signal converter receives a plurality of optical signals propagated through the waveguide, despreads the received optical signals by the plurality of spreading codes, and despreads the plurality of light signals. The transmission apparatus according to claim 1, wherein the signal is converted into a plurality of electric signals and each electric signal is supplied to a corresponding antenna element. A transmission device for transmitting a transmission signal;
a receiving device that receives the transmission signal using n (n is an integer of 2 or more) antenna elements,
The transmitter is
A waveguide for propagating an optical signal;
A transmitter for generating the transmission signal;
The transmission signal from the transmitter is converted into m (m is an integer of 2 or more) optical signals that can be distinguished from each other, and the converted m optical signals are incident on the waveguide. A converter,
M antenna elements provided corresponding to the m optical signals;
The m optical signals propagated through the waveguide are received, the received optical signals are separated from each other, and the separated m optical signals are converted into m electrical signals. A second signal converter for supplying a signal to a corresponding antenna element. The first signal converter converts the transmission signal into m optical signals having mutually different wavelengths, and inputs the converted m optical signals as one optical signal to the waveguide,
The transmission / reception system according to claim 5, wherein the second signal converter receives an optical signal propagated through the waveguide and separates the received optical signal into the m number of optical signals. The first signal converter converts the transmission signal into m optical signals having the same wavelength, and sequentially inputs the converted m optical signals to the waveguide in a time division manner,
The second signal converter sequentially receives m optical signals propagated in the waveguide, converts the received m optical signals into m electrical signals, and converts each electrical signal to a corresponding antenna. The transmission / reception system according to claim 5, wherein the transmission / reception system sequentially supplies the elements. The first signal converter converts the transmission signal into a plurality of optical signals having the same wavelength, spreads the converted optical signals by m different spreading codes, and converts the converted m signals Are incident on the waveguide by code division as one optical signal,
The second signal converter receives m optical signals propagated in the waveguide, despreads the received m optical signals by the m spreading codes, and despreads m 6. The transmission / reception system according to claim 5, wherein the optical signals are converted into m electrical signals and each electrical signal is supplied to a corresponding antenna element. The interval between the m antenna elements when the transmission rate of the transmission signal is the first transmission rate is defined as a first interval, and the transmission rate of the transmission signal is lower than the first transmission rate. When the interval between the m antenna elements at the transmission rate is the second interval,
The transmission / reception system according to any one of claims 5 to 8, wherein the m antenna elements are arranged at the second interval.

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