A Circular Spatial Spectrum Direction Finding Method

A cyclic space and direction finding technology, applied in the field of cyclic space spectrum direction finding, can solve the problems of low signal-to-interference ratio direction finding ability and same-frequency spatial resolution ability, influence of direction finding results, large difference in amplitude of multiple same-frequency signals, etc. , to achieve the effect of solving the low signal to interference ratio signal direction finding

CN105652234BActive Publication Date: 2018-07-20KUSN JIUHUA ELECTRONICS EQUIP FACTORY
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
Publication Date
2018-07-20

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Abstract

The invention discloses a cyclic spatial spectrum direction finding method. The method includes the steps that firstly, according to signals received by a direction finding antenna array, cyclic frequency or conjugate cyclic frequency of the signals is obtained; secondly, by means of the cyclic frequency or the conjugate cyclic frequency, a cyclic autocorrelation matrix or a conjugate cyclic autocorrelation matrix of the signals is obtained; thirdly, by means of the cyclic autocorrelation matrix or the conjugate cyclic autocorrelation matrix, feature vectors of a signal space and a noise space are calculated, a cyclic spatial spectrum of the signals is calculated by means of the feature vector of the noise space, and the arrival direction of the signals is determined by searching for the peak value of the cyclic spatial spectrum. According to the cyclic frequency or the conjugate cyclic frequency of the received signals, the cyclic autocorrelation matrix or the conjugate cyclic autocorrelation matrix is calculated, direction finding of the cyclic spatial spectrum is achieved, the problem that precision of low-signal-to-interference-ratio signal direction finding and arrival-wave-direction close signal direction finding of multiple same-frequency signals is reduced is solved, and multiple same-frequency targets with the number larger than antennas can be subjected to direction finding.
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Description

technical field

[0001] The invention relates to a cyclic space spectrum direction finding method. Background technique

[0002] With the development of electronic technology and communication technology, radio direction finding technology is more and more widely used in civilian and military fields. It can realize the direction finding and positioning of radiation sources such as radio stations, which has great practical significance. Spatial spectrum direction finding technology is a new airspace signal processing technology developed in the past 30 years. It is mainly developed on the basis of beamforming and time domain spectrum estimation. Because it breaks through the Rayleigh limitation of the array aperture on the incoming wave direction in the past spectrum estimation, and has high direction finding accuracy, it has been widely used in actual direction finding and positioning systems.

[0003] Although the existing spatial spectrum direction finding technology can a...

Examples

Embodiment 1

[0032] The antenna array for receiving signals is an L-shaped array composed of 9 whip antennas, and a 200-watt short-wave transmitter is arranged as the target station at the transmitting point 500 kilometers away from the receiving point. The target station chooses to transmit signals on the same transmission frequency as the high-power broadcast station, and the received signal amplitude of the broadcast station is more than 10dB higher than that of the target station, thus verifying the improvement of the direction finding ability of the circular space spectrum direction finding method for low signal-to-interference ratio signals .

[0033] The target station transmits an AM signal on the same frequency as the high-power station, and calculates the cycle frequency or conjugate cycle frequency of the received mixed signal of the target station signal and the broadcast station signal according to step a) to obtain the cycle frequency or conjugate of the target station signal ...

Embodiment 2

[0036] The receiving signal array also uses an L-shaped array composed of 9 whip antennas. Two target stations with similar azimuths are arranged about 3 kilometers away from the receiving point, and the actual azimuth angles are 117 degrees and 120 degrees respectively. Through the simultaneous transmission of two target stations on a series of the same frequencies, the improvement of the same-frequency spatial resolution of the circular spatial spectrum direction-finding method is tested.

[0037] The two target stations transmit AM signals and QPSK signals respectively on the same frequency, and calculate the cycle frequency or conjugate cycle frequency of the received mixed signals of the two target stations according to step a), and obtain the cycle frequency or conjugate cycle of the signals of the two target stations respectively frequency; then calculate the cyclic autocorrelation matrix or the conjugate cyclic autocorrelation matrix according to step b), and finally us...