As an crucial part of global satellite navigation machine, the frequency band of DME will overlap with that of the navigation sign, with the Distance Measuring intention to motive the sign from the DME platform to be regular through the worldwide Navigation satellite tv for pc gadget receiver and form interference. therefore, it’s miles of terrific importance to have a look at an powerful set of rules to suppress DME pulse interference. This paper has the following studies on this problem. on this paper, wavelet packet rework is used to remedy for the suppression of DME pulse interference method, wavelet packet analysis belongs to the linear time-frequency analysis method, it has top time-frequency localization traits and the sign adaptive capacity, due to the characteristic of wavelet packet and parameter choice of DME will affect the potential of interference suppression, combining with the principle of wavelet threshold, characteristic kind and decomposition collection are mentioned to prove the validity of the selected parameters at the Distance Measuring pulse interference suppression.
satellite navigation gadget’s predominant feature is to realise the location, velocity and timing, global position machine is an vital a part of GNSS, GPS L5 signal spectrum and B2 signal common Beidou satellite Navigation gadget in our u . s ., because there had been many radio navigation systems inside the work on this band, so the GPS L5 receiver is dealing with the complicated electromagnetic environment, DME system is one in every of the most important interference resources to the interference. In severe cases, GPS receiver can not be as it should be placed, which poses a ability risk to the implementation of PBN of civil aviation. Distance Measuring currently, there are three main strategies to cope with interference suppression of DME device, namely, time domain processing technique, frequency domain processing method, and time-frequency area mixed processing method [1].
The time domain processing technique is the most commonplace pulse interference suppression method, that’s to suppress the interference through placing a threshold inside the time domain steady with the noise degree and zeroing the acquired signal samples that exceed the threshold. within the case of excessive pulse interference density, this method will lose a huge range of useful satellite signals.
in comparison with the time-area processing method, the frequency-domain filtering Distance Measuring method can clear out the interference greater successfully, however at the identical time, there will also be cases of filtering out beneficial indicators [2]. due to the variety of aircraft flight surroundings, the frequency-area processing approach based on notch filter out calls for the development of different notch filters, which is not viable within the changeable flight environment.
compared with the former two techniques, the time-frequency blending technique can keep extra beneficial signals to suppress the interference. a way to stumble on the middle role of the heart beat is the key of this method, however if there is a very horrific interference environment, it is hard to obtain this method.
To sum up, the traditional time-frequency analysis is not able to clear out the interference indicators while maintaining the beneficial signals as an awful lot as feasible. therefore, based totally at the detection and suppression of DME interference inside the domain of wavelet packet Distance Measuring remodel, this paper similarly systematically studies and analyzes the function kind, decomposition order and the selection of threshold price.