With the continuous improvement of bandwidth, dynamic range, and noise coefficient of optical transceivers, optical fiber transmission links in radio telescope are common. Some high-performance radio telescopes at home and abroad have adopted optical fiber transmission systems to achieve high-quality microwave signal transmissions, such as ovens Valley array in the United States, GBT, EVLA, Nobeyama in Japan, even in South Korea, etc., as well as the world's largest "SkyEye" radio telescope inde

Laser Doppler radar is an exciting radar that uses a Doppler system to obtain target motion information. Because of the high coherence, monochromaticity, and directivity of laser, heterodyne detection is possible. The lidar, which receives the frequency shift information of laser Doppler and obtains the radial velocity component using the optical heterodyne detection technology, is called the coherent Doppler lidar.

In addition to the glass aspheric lens, there is a plastic aspheric lens. Plastic molding is the injection of molten plastic into an aspheric mold. Compared with glass, plastic has poor thermal stability and compression resistance, so it needs special treatment to obtain a similar aspheric lens. However, the plastic aspheric lens is characterized by low cost, lightweight, and easy to form, widely used in occasions with moderate optical quality, insensitive thermal stability, and low-pressure re

Kg ODL manual optical adjustable delay device is a portable device that can adjust the optical delay. It has the characteristics of high integration and low cost. The device can provide 330ps optical delay and realize accurate delay control through rotation control. With the length ruler marked on the panel, precise information of uncertainty can be read out immediately in mm or PS.

The kg-EDFA series products independently developed by conquering optoelectronics Co., Ltd. are fiber-optic power amplification equipment specially designed for laboratory and factory test environments. They are internally integrated with a high-performance pump laser, high gain erbium-doped fiber, and unique control and protection circuit, which realize low noise and high stability output. AGC, ACC, APC three working modes are optional and widely used in fiber sensing and optical fiber sensing

In the above three eye patterns, we analyze three situations that lead to lousy eye patterns: impedance mismatch, jitter, and noise. How can these three situations be seen from the eye chart? If the "1" level line of an eye chart is thick and uneven (above), it is caused by impedance mismatch. To solve the problem, we should guarantee the impedance matching from the beginning to the end. If the rising and falling edge of the eye chart is relatively thick (in the middle), it is caused by jitter.

The test is carried out by using a conquering photoelectric carrier suppression SSB modulator. Kg-inbox-SSB-1550 series suppression carrier SSB modulation unit is a highly integrated product with independent intellectual property rights of conquering photoelectrically. The instrument unit integrates DFB laser, Mach Zehnder dual parallel modulator, bias controller, RF driver, phase shifter, and other necessary components and realizes the generation of suppression carrier SSB through driver circu

In the OTDR system, if the light source's linewidth is narrow enough and the coherence is high enough, the scattered light returned from different parts of the fiber will interfere. The phase-sensitive OTDR system designed using the scattered light's coherence can detect the interference of the weak signal, which the traditional OTDR system can not see.

The system uses a narrow linewidth laser with a 1550nm working wavelength and divides the light source into two channels through a 3dB coupler. One of the optical signals is modulated by the electro-optic modulator (eom1) to pulse light, amplified by EDFA, filtered by grating, and then entered the sensing fiber. Another optical signal of the coupler is modulated by an electro-optic modulator (eom2) to produce a frequency shift of about 11 GHz. The stimulated Brillouin scattering has the most sub

Half-wave voltage is an important parameter to measure the electrical characteristics of devices. The lower the half-wave voltage, the better the electrical parts of devices. In this paper, the half-wave voltage of the integrated device is measured using the principle of Mach Zehnder intensity modulation. The test schematic diagram is shown in Figure 5. Load sawtooth wave electric signal with saw period of T and peak value of VPP on one arm of Mach Zehnder intensity modulation system. Use a do