摘要:
An optical-space transmission apparatus for use in communication by using light propagating in a space includes a light-receiving unit, an optical system including a movable mirror and introducing light incident thereon to the light receiving unit with the movable mirror, a controller controlling drive of the movable mirror, and a detecting unit detecting an intensity of the light received in the light-receiving unit. The controller modifies a control characteristic of the movable mirror in accordance with a change in the received-light intensity.
摘要:
An optical-space transmission apparatus for use in communication by using light propagating in a space includes a light-receiving unit, an optical system including a movable mirror and introducing light incident thereon to the light receiving unit with the movable mirror, a controller controlling drive of the movable mirror, and a detecting unit detecting an intensity of the light received in the light-receiving unit. The controller modifies a control characteristic of the movable mirror in accordance with a change in the received-light intensity.
摘要:
An optical space communication apparatus for performing communication with an party apparatus by transmitting a light signal into a free space includes a signal selector for selecting and intercepting a beam including a light beam and background light from the party apparatus, a detector for detecting a beam via the signal selector, and a signal outputting device for comparing an output signal outputted from the detector when the signal selector intercepts the light beam from the party apparatus, with an output signal outputted from the detector when the signal selector does not intercept the light beam from the party apparatus, and for outputting a signal representing a difference between the output signals.
摘要:
A two-way optical transmitter in which optical transmitters each having light projecting means and light receiving means on an optical axis intersecting the optical axis of the light projecting means are disposed in opposed relationship with each other with a predetermined distance interposed therebetween and which effects two-way optical transmission, wherein a polarizing beam splitter, having a cemented surface forming a certain angle with respect to the optical axes of the light projecting means and the light receiving means is installed near the point of intersection between the two optical axes, linearly polarized light from the light projecting means is reflected by the cemented surface of the polarizing beam splitter to thereby provide transmission light, and an optical axis leading from the polarizing beam splitter to the light projecting means or an optical axis leading from the polarizing beam splitter to the light receiving means is set at an angle of approximately 45.degree. with respect to the vertical direction when the apparatus is seen from on the optical axis of the transmitted light.
摘要:
An optical communicating apparatus has an optical transmitting unit and an optical receiving unit which are accommodated in the same casing. The apparatus is provided with a distributing circuit for supplying a power source to the optical transmitting unit and the optical receiving unit. A modulation device and a demodulation device are connected to the optical space communicating apparatus. The modulation device modulates a transmission signal and has a first power source unit to supply a power source to the distributing circuit. The demodulation device demodulates a reception signal and has a second power source unit to supply a power source to the distributing circuit. A switching device is arranged between the distributing circuit and the first power source unit or between the distributing circuit and the second power source unit. The switching device selects either one of the first and second power source units to connect the selected power source unit to the distributing circuit, so that the power source is applied to each unit in the apparatus through the distributing circuit.
摘要:
There are provided digital communicating method and apparatus for modulating digital signals into chirp signals and performing the communication. In this method, pulses indicative of digital signals of codes "1" and "0" are modulated, the modulated pulse signals are converted into chirp signals, the chirp signals are converted into the optical signals and output as transmission signals, and the digital signals are input and the pulses based thereon are generated. A wave of a predetermined frequency is multiplied by the pulses indicative of "1" and "0" of the digital signals and the modulation is executed. The communication signals can be converted into the chirp signals by the chirp conversion elements using the surface acoustic wave-dispersive delay lines having different converting characteristics by the simple construction. On the reception side, the modulated signals are demodulated by the chirp conversion elements having characteristics opposite to those of the chirp conversion elements on the transmission side. Thus, the code signals of "1" and "0" can be accurately discriminated and the error rate can be reduced. The communication reliability is improved.
摘要:
An optical free-space communication apparatus includes a first light-emitting source for emitting a first transmission optical beam having a plane of polarization in a predetermined direction, the first transmission optical beam being modulated according to a primary signal containing communication information, a second light-emitting source for emitting a second transmission optical beam having a plane of polarization perpendicular to the plane of polarization of the first transmission optical beam, the second transmission optical beam being modulated according to an auxiliary signal for angle detection, a transmitting optical system for emitting the first and second transmission optical beams out of the apparatus as optical beams each having a predetermined angle of divergence, and a driving unit for redirecting the outgoing paths of the first and second transmission optical beams, wherein the second transmission optical beam has a larger angle of divergence than the first transmission optical beam.
摘要:
An optical space communication method is for communication with a laser as a radiative source and with a light signal therefrom propagating in the atmosphere. In the method, the communication is performed under the following conditions. In case a transmission distance of optical space communication is between 100 m inclusive and 200 m, the laser is a laser with an oscillation wavelength L (nm) in a wavelength range of between 967 run inclusive and 1110 nm or in a wavelength range of between 1165 nm inclusive and 1315 nm, whereas in case the transmission distance is not less than 200 m, the laser is a laser with an oscillation wavelength L (run) in a wavelength range of between 986 nm inclusive and 1090 nm or in a wavelength range of between 1225 nm inclusive and 1295 nm. At any position in a transmission path between a transmitter exit and a receiver entrance, an irradiance is set to at most 6.47.multidot.10.sup.(L-700)/500 (W/m.sup.2) where the oscillation wavelength L (nm) of the laser is in a wavelength range of 950 nm to 1050 nm while to at most 32.3 (W/m.sup.2) where the oscillation wavelength L is in a wavelength range of 1050 nm to 1400 nm.
摘要翻译:光学空间通信方法用于与激光作为辐射源通信,并且其光信号在大气中传播。 在该方法中,在以下条件下进行通信。 在光学空间通信的传输距离在100微米到200微米之间的情况下,激光器是在波长范围为967nm至1110nm之间或在波长范围内的振荡波长L(nm)的激光器 1165nm和1315nm,而在传输距离不小于200μm的情况下,激光是在986nm至1090nm之间或在波长范围内具有振荡波长L(游程)的激光器 在1225nm和1295nm之间。 在发射器出口和接收器入口之间的传输路径中的任何位置,辐射度被设定为激光器的振荡波长L(nm)为至多6.47×10(L-700)/ 500(W / m 2) 波长范围为950nm至1050nm,而至多32.3(W / m 2),其中振荡波长L在1050nm至1400nm的波长范围内。
摘要:
This specification discloses a communication apparatus provided with light emitting means for generating transmission light modulated by an information signal, light receiving means for receiving modulated reception light, an optical member for reflecting one of the transmission light and the reception light and transmitting the other therethrough, a reflecting member for reflecting the transmission light emerging from the optical member to the transmission side and reflecting the reception light to the optical member, light splitting means for splitting part of the reception light obtained through the optical member, detecting means for detecting the positional state of the light obtained from the light splitting means, and driving means for rotatively driving the reflecting member about two axes in accordance with the positional state of the light detected by the detecting means. The specification further discloses an apparatus which has a lens unit having positive refractive power disposed between the light emitting means and the light splitting means and in which at least one lens constituting the lens unit is moved to thereby vary the state of the light beam.
摘要:
An optical space communication apparatus comprises a transmitter and a receiver. The transmitter has a main signal generator for producing a main signal, an auxiliary signal generator for producing an auxiliary signal in a frequency band different from that of the main signal, a combiner for combining the main signal with the auxiliary signal, an electro-optical converter for converting a combined signal of the main signal and the auxiliary signal into a light signal, and a transmission optical system for transmitting the light signal formed in light beam. The receiver has a reception optical system for receiving the light signal in light beam and a photo-electric converter for converting the light signal into an electric signal. The receiver further has a separator for separating the electric signal converted by the photo-electric converter into a main signal and an auxiliary signal, and an auxiliary signal detector for detecting the auxiliary signal separated by the separator.