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As the most sensitive single-dish radio telescope, it is a great challenge for the Five-hundred-meter Aperture Spherical radio Telescope (FAST) to mitigate Radio Frequency Interference (RFI). The solutions for RFI mitigation of FAST consist of the Electromagnetic Compatibility (EMC) design and measures of the instruments, the maintenance of a Radio Quiet Zone (RQZ) and post-processing RFI removal algorithms. However, with the development around the FAST site, the radio environment has been affected and become complicated. In order to strengthen the operation and management of the FAST RQZ, a RFI intelligent monitoring and positioning system has been proposed, which focuses on monitoring, identifying, and positioning RFI sources, especially some mobile interference sources such as drones in the core zone of the RQZ with the radius of 5 km around the FAST site. The preliminary design and two key technologies including RFI intelligent identification and RFI source localization have been discussed roughly.

In view of the different probability of residents of different floors in high-rise buildings taking the elevator during the peak period of a day, this paper proposes an optimization scheduling model based on Monte Carlo Algorithm, making the existing model more accurate. The automatic counting module (ACM) based on infrared sensor is used to measure and record the number of passengers on different floors. On the basis of a large amount of data obtained from the research, the probability of taking the elevator is calculated, and the cubic polynomial fitting curve is generated based on the least square method, which is applied to the implementation of Monte Carlo Algorithm, and an optimized elevator scheduling model is obtained. At the same time, the optimized model and the existing model are compared in different aspects to generate visual comparison result. In the hypothesis of this paper, under the condition that the number of floors is 20 and the number of households on each floor is 50, the existing model will have a relative error of 10%-20%, and the number of passengers transported by the elevator below 10 floors will be significantly reduced with a relative error of more than 10%. At last, from the elevator scheduling model, a “one-to-many” model can be abstracted. We find that the model optimization idea used in this problem has certain guiding significance in dealing with some other practical problems.

The Five-hundred-meter Aperture Spherical radio Telescope is now in the commissioning stage. Due to its extreme sensitivity, it is a great challenge for FAST to mitigate the Radio Frequency Interference (RFI) not only from the telescope itself, but also from the transmitter outside the site. The solutions for RFI mitigation of FAST include the Electromagnetic Compatibility measures of the telescope and the maintenance of radio quiet zones around the site. The new pulsars detected by FAST have indicated the effectiveness of the solutions of RFI mitigation.

Five-hundred-meter Aperture Spherical radio Telescope (FAST) is a Chinese mega-science project to build the largest single dish radio telescope in Guizhou province, Southwest China. The construction of FAST will involve many kinds of analog and digital electrical equipments. The electrical equipments are potential threat to radio observation due to its ElectroMagnetic Interference (EMI) emission. The EMI should be safely shielded when FAST telescope operates. The shielding effectiveness of large shielding enclosures can be tested with two log periodic antennas, signal generator and spectrum analyzer. It is not suitable to test small shielding enclosure for that is not possible to put big antenna and signal generator inside. In this paper, an effective shielding effectiveness measurement system for the small shielding enclosure is introduced. This measurement system uses a frequency synthesizer of Valon Technology as signal generator which can measure the shielding effectiveness no more than 100dB in a frequency range of 23–6000MHz. Some of measurement results of shielding effectiveness are also presented.

After five and a half years construction, the main structure of Five-hundred-meter Aperture Spherical radio Telescope (FAST) has been completed in September 2016. Meanwhile, a Radio Quiet Zone (RQZ) with radius 30 km has also been established. In order to evaluate the Radio Frequency Interference (RFI) influence from the mobile base stations within radius 5 km (the restriction zone of RQZ) around FAST, several measurements have been carried out when these stations were closed temperately. Comparing the RFI measurement results before and after the closure of these stations, the interference has been decreased more than 30 dB. Since November 1 2016, all the mobile base station within the restriction zone of FAST RQZ have be closed permanently to avoid the risk of the receiver saturation due to the interference coming from these stations.

Five-hundred-meter Aperture Spherical radio Telescope (FAST) is a Chinese mega-science project to build the largest single dish radio telescope in the world. The first light of FAST is expected in September 2016. Due to the high sensitivity of FAST, it is very sensitive to the radio frequency interference coming from the electrical and electronic equipments of telescope itself. In order to assure the realization of the scientific goals of the telescope, the electromagnetic compatibility (EMC) study on FAST at the design and construction stages, has been carried out to decrease the possibility of the interference from the telescope. Several examples, such as EMC designs and measurements for actuator and focus cabin, have been introduced briefly.