The Research Of Multi Antennas Of Mobile Communication Base Station Electromagnetic Radiation

In today’s rapid development of communication industry, in order to improve the reuse rate of base stations, communications company has carried out the co-construction and sharing of the base station cooperation plan. The cooperation project leads to a higher level of electromagnetic radiation intensity around the base station due to more antennas being placed on this base station location, thus, to more accurately calculate and predict the antenna’s electromagnetic radiation intensity is an important and meaningful work.The most common method to predict electromagnetic radiation of multiple antennas is maximum electromagnetic radiation assessment. This calculation method assumes the multiple antennas gathered together as one point,ignoring the distance between antennas, and then through a simple accumulation of electromagnetic radiation to calculate the electromagnetic radiation level of the predicted point. This approach often obtains a good result for evaluation when the distance between measurement point and the base station is long. But when at close range measurement process and without big construction, a phase difference generated by the antennas spacing during the emission of electromagnetic waves, to a certain extent, will affect the precision of prediction results. Large deviation may be produced between predicted results and real situation, and thus real situation intensity of electromagnetic radiation surrounding the base station may not be reflected.Aiming at the shortcomings of the traditional method, this paper first analyzes the advantages and disadvantages of traditional formula of electromagnetic radiation,then analyze the distance generated by antenna spacing difference affecting in a certain extent the accuracy of the traditional formula of electromagnetic radiation, and finally analyze in detail the impact of distance difference to the prediction result. Then combining the formula of electromagnetic radiation of single antenna with basic principle of multiple antenna model, on this basis, this paper proposes a formula of electromagnetic radiation of multiple antenna based on distance difference, and predict electromagnetic radiation level of dual/tri/multi antennas by using this formula.On the basis of the predicted results of electromagnetic radiation of dual/tri/multi antennas, we find real dual/tri/multi antennas base station.By using instruments PMM8053 B for field measurements, we compare the theoretical calculation result with observed data to verify the accuracy of the formula. Through the consistency of actualmeasurement and theoretical calculation results, the feasibility of the calculation method of this paper is verified.