RU2678918C1 - Method of modulating laser beam with quartz resonator with corner reflectors - Google Patents

Abstract

FIELD: information technology.SUBSTANCE: method relates to the field of information transmission and concerns a method of modulating a laser beam with a quartz resonator with corner reflectors. Method includes the use of a set of rectangular tetrahedrons with mutually perpendicular mirror reflecting planes located in one plane. On the side opposite to the reflecting planes, a pulse coded quartz resonator is attached thereto, which, as a result of supplying digital information in the form of electrical pulses, forms mechanical vibrations in accordance with the piezoelectric effect to change the frequency of the reflected laser radiation in accordance with the Doppler effect.EFFECT: reducing power consumption and providing the possibility of transmitting digital information from a microsatellite on a re-reflected beam.1 cl, 2 dwg

Description

The method relates to communication technology and can be used to transmit digital information from the microsatellite.

Known corner reflector [1], made in the form of a tetrahedron with three metallized reflecting faces, in which two dihedral angles are π / 2, and the third is π / 2 (S + 1), where s 1, 2, 3, 4. Lengths its ribs R1, R2, R3 are selected from the ratio R1: R2: R3 = a: a: 1. Also known is a prismatic corner reflector [2], made in the form of a trihedral pyramid, the dihedral angles between the side reflective faces of which are also equal to π / 2, π / 2 and π / 2 (S + 1), where S is a positive integer, the edges of the reflector made with sizes P1 and P2, determined from mathematical relations. The refractive index of the material of the reflector is also determined from the above ratio. Known corner reflectors are used to provide reflection of laser radiation from various objects, including Earth satellites, in the exact opposite direction.

A disadvantage of the known technical solutions is that there is no possibility of transmitting digital information from the microsatellite via a reflected laser beam.

The purpose of this modulation method is to transmit digital information from the microsatellite via a laser beam of digital information re-reflected from the corner reflector.

This is achieved by the fact that on the side opposite to the reflecting planes, a code-pulsed quartz resonator is attached, which, as a result of supplying digital information in the form of electric pulses, will generate mechanical vibrations in accordance with the piezoelectric effect to change the frequency of the reflected laser radiation in accordance with the Doppler effect.

In FIG. 1 shows a fragment of a unit cell of a corner reflector with a code-pulse quartz resonator of a reflected laser beam for transmitting digital information from a microsatellite. The laser beam after a single, double or triple re-reflection (depending on the orientation of the corner reflector relative to the beam) will be directed back to the ground communication station. The reflecting surfaces 1 are in physical contact with the quartz resonator 2.

In FIG. 2 shows a battery of unit cells to increase the efficiency of the corner reflector.

The method is implemented as follows. The ground-based laser scans a portion of the sky in the area of the proposed location of the microsatellite. When a laser beam hits the corner reflector, it will be retroreflected towards the emitting laser. Upon receipt of the reflected beam, the ground station transmits digital information to the microsatellite via a laser beam in optical form. Then, the ground station switches to receiving digital information. For this, the laser beam provides continuous illumination of the corner reflector. The on-board computer of the microsatellite provides digital information to a code-pulse quartz resonator, which, when exposed to electric pulses, converts them into mechanical vibrations of crystals, and these, in turn, act on the reflective surfaces of the corner reflector. As a result, the reflected laser beam will be modulated in accordance with the Doppler effect, which will allow high-speed transmission of a significant amount of information from the microsatellite to a ground communication station. An additional advantage is the high energy efficiency of this method of modulating the laser beam, because Instead of a power-consuming transceiver and antenna system with a change in the radiation pattern, the proposed modulation method will require minimal electric energy to act on the quartz resonator. This will reduce the power consumption of the microsatellite in order to redirect the released energy to perform other functions.

The disadvantage of the proposed method for modulating the laser beam is the dependence on weather conditions, which can affect the parameters of the laser beam. However, in the case of the global deployment of such a method of modulating a laser beam for the orbital constellation of microsatellites, it will be possible to deploy an optical communication line between all microsatellites and transmit information from them to that ground communication station, which will be in favorable weather conditions.

Literature

1. RF patent No. 2020668. Corner reflector / Titov A.D. Publ. 09/30/1994.

2. RF patent No. 2101740. Prismatic angle reflector / Titov A.D. Publ. 01/10/1998.

Claims (1)

A method of modulating a laser beam with a quartz resonator with corner reflectors, implemented by a set of rectangular tetrahedra located on the same plane with mutually perpendicular mirror reflecting planes, characterized in that a code-pulse quartz resonator is attached from the side opposite to the reflecting planes, which, as a result of supplying digital information to in the form of electrical impulses will form mechanical vibrations in accordance with the piezoelectric effect for changing frequencies the reflected laser beam in accordance with the Doppler effect.

Images