Diagnosis method for non-linear interference outside communication band of transmission device

Abstract

The invention discloses a diagnosis method for nonlinear interference out of communication frequency band of a transmitting device, comprising the following steps: (1) a behavioral-level simulation model of a radio-frequency head of the transmitting device is established; (2) simulation calculation is performed on the behavioral-level simulation model in the step one to obtain the out-of-band output frequency spectrum at the radio-frequency head of the transmitting device; (3) the energy transferring relationship between an interfering transmitting device and an interfered receiving device is established, and is expressed by dB as: Pri(f)=Pti(f)-Ltl(f)+Gt(f)-La(f)+Gr(f)-Lrl(f); and Pri(f) is calculated; and (4) the interference from the transmitting device to a receiving device is diagnosed according to the Pri(f) obtained in the step (3) and an interference judgment condition Pri(f)+Sm is more than or equal to Ps'(f). The method can flexibly process various nonlinear parameters of different sub-circuit modules, fast calculate the out-of-band output frequency spectrum of the radio-frequency head of the transmitting device, diagnose the interference from the transmitting device to the receiving device according to energy transferring relationship between the transmitting device to the receiving device and an interference condition, provide powerful tools for the electromagnetic interference diagnosis of a plurality of communication systems on a same platform, and provide a guideline for a communication device to adopt an effective electromagnetic compatibility measure.

Description

technical field [0001] The invention belongs to the technical field of electromagnetic compatibility, and relates to a diagnostic method for nonlinear interference outside the communication frequency band of transmitting equipment on a platform including multiple sets of communication systems, specifically, a diagnostic method for nonlinear interference outside the communication frequency band of transmitting equipment . Background technique [0002] The airborne communication platform includes multiple sets of transmitting and receiving equipment, high-power transmitters and high-sensitivity receivers are installed in a limited space, and electromagnetic signals are dense. Most aircraft materials use composite materials, which may cause serious mutual interference between communication devices in this local space area, resulting in a decrease in the performance of communication devices. In order to achieve the maximum communication distance, the transmission power of the t...

AI Technical Summary

Problems solved by technology

[0005] After the electronic equipment meets the electromagnetic compatibility indicators stipulated in the national standard, it can be regarded as meeting the standard. However, this method of tailoring the national standard is not necessarily effective. After cascading and integrating multiple qualified electronic equipment, electromagnetic compatibility problems will also occur.

The emission equipment index is qualified, but it may still cause electromagnetic compatibility problems when it is placed on a complex multi-communication system platform. It is easy to ignore the radiation interference caused by the non-linearity of the transmission equipment communication band.

In the design stage of the transmitting equipment or before the finalization of the equipment, the performance indicators in the communication frequency band are often considered. The suppression outside the communication frequency band only needs to meet the specified value of the national standard. However, due to nonlinearity, the distance of the transmitting equipment outside the communication frequency band is very long. Other nearby receiving equipment may cause strong interference

Generally, after the signal interference phenomenon outside the communication frequency band of the transmitting equipment is fully exposed, a large number of testing methods are used to locate the interference source. This not only consumes a lot of manpower and material resources, but also a large number of tests will affect the life of the equipment.

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