Analysis and experiment show that the laser divergence of 0. 4 mrad is obtained for the communication terminals based on the optical system, with the pointing error of less than 0. 3 mrad, on which free space communication in 2 km can be achieved.
Another important advantage of distributed array is when the actual rms pointing error is larger than the designed value,the power penalty can be reduced greatly by changing the distance between the sub-apertures.
Pointing error of transmitter and atmospheric turbulence cause signal fading for satellite-to-ground laser communication,and the anti-fading characteristics of distributed ground-based array receiver with optical preamplifiers are analyzed.
Simulation results show that for given root-mean-square(RMS) pointing error and required average bit error rate,there exist optimal transmitting beamwidth,receiver antenna diameter and space optical coupling parameter that minimize transmitted power,the required transmitted power is not decreased even using a receiver antenna larger than optimum antenna.
Based on the scalar theory,Fresnel formula and Fourier transform are used to analyze the effects of the surface reflection of SiO 2 thin film and substrate,the alignment errors and the angle of incidence of light beam on the diffractive efficiency of 16 step Fresnel lens.
在标量衍射理论的基础上 ,应用菲涅耳公式和傅里叶变换分析 Si O2 薄膜和基底的表面反射、对准误差以及入射角对 1 6阶菲涅耳透镜衍射效率的影响 .
This paper specifically analyzes the philosophy of requirements of permissible out-of-roundness for shells, of shape tolerance for heads, and of alignment tolerance for sections at edges to be welded which are specified by ASME Boiler and Pressure Vessel Code.
A measure of the resonator alignment error is derived by partitioning a 1% sample of the laser output into quadrants, and using standard electronic circuits to compare the average power present in each quadrant.
The alignment error between two DXL-processed layers has been measured to be within ±5?μm range.
Alignment error of an image sensor relative to the optical axis of a star sensor head and alignment errors between four heads were calculated from pictures taken in an orbital experiment.
The limits of effectiveness of this synchronization system are then discussed, especially with regard to the accumulation of timing jitter as well as of alignment error.
The third strain-sensing element was used to calculate the gage alignment error and "true" longitudinal and transver e strains.
Some interaction between eye and head eccentricity also contributed to the pointing error.
The intensity distribution in a Gaussian beam is represented by a bundle of rays in which each ray has a random pointing error.
Without VS 73% of the volunteers showed a systematic horizontal pointing error towards the right side.
Consequently, the OP maneuver has a large pointing error.
The root mean square of pointing error of moving cable car was measured and the displacements of cable car within the wind speed of 8 m/s, which is the maximal wind speed of the place where the FAST will be located, were evaluated.
The moiré signals generated by two pairs of quadruple gratings on mold and wafer are optically projected onto two photo-detector arrays, then the detected moiré signals are used to estimate the alignment errors in the x and y directions.
An optimal algorithm of panoramic sewing of images in the presence of alignment errors has been synthesized on the basis of the criterion of a posteriori probability maximum.
Alignment errors in the strong-focusing synchrotron
Although alignment errors are known to occur due to limb rotation, the magnitude of this effect is unknown.
Rotation and flexion of 5° led to significant alignment errors of 3.4° and 2.8°, respectively, for internal and external rotations.