DEVICE FOR SUPPRESSING NARROW-BAND INTERFERENCE

摘要

The device belongs to the field of radio electronics and can be used in radio receivers operating under narrowband interference conditions. The technical problem, the solution of which is directed to the claimed device, is to provide suppression of narrowband interference regardless of the probability density distribution of the interference amplitude and exclusion of the suppression of the useful signal at the output of the device under the influence of low power interference or complete absence of interference. The solution of this problem is achieved by the fact that the device contains an amplitude detector, which receives a mixture of useful signal and interference, a block for obtaining equiprobable reports, Q non-linear elements, 2Q multipliers, Q matched filters, a weighting unit and an adder, the output of the amplitude detector is connected to the input of the unit for obtaining equiprobable reports whose output is connected to the input of each nonlinear element, the output of each nonlinear element is connected to the first input of the corresponding multiplier whose second input is connected to the input of the amplitude detector and the output is connected to the input of the corresponding matched filter , whose output is connected to the corresponding input of the weighting coefficient calculating unit, and also to the first input of the corresponding multiplier, the second input d is connected to the corresponding output of the weighting coefficient calculating unit, and an output connected to a respective common input adder, the output of which obtain the useful signal with significantly suppressed interference. Thanks to the block for obtaining equiprobable reports, as well as the representation of the set of amplitude characteristics of nonlinear elements in the form of a Legendre polynomial of order Q, the device is insensitive to the kind of interference distribution and its power, which ultimately stabilizes the detection threshold and a stable probability of false alarm. Thus, it is required to calculate the correct detection threshold once based on the desired false alarm value, and it will be constant for any changes in the probability density of the envelope of the interference.