Frequency hopping anti-interception method in orthogonal frequency division multiplexing (OFDM) system

An anti-interception, frequency hopping technology, applied in transmission systems, multi-frequency code systems, electrical components, etc., can solve the problems of long time, limited frequency hopping speed, large occupied bandwidth, etc., to improve signal-to-interference noise ratio, narrowband Interference suppression, achieving low-complexity effects
CN104780133AActive Publication Date: 2015-07-15北京航天科工世纪卫星科技有限公司
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Patent Information

Authority / Receiving Office
CN · China
Current Assignee / Owner
北京航天科工世纪卫星科技有限公司
Publication Date
2015-07-15

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Abstract

The invention provides a frequency hopping anti-interception method in an orthogonal frequency division multiplexing (OFDM) system, which can improve signal to interference plus noise power ratio, and lowers the effect caused by broadband interference. The method comprises a small amplitude frequency hopping method for narrow-band interference and a random frequency hopping method for broadband interference. The space of each frequency point is equal to the bandwidth of a subcarrier, and the frequency points are not so excessive; and a plurality of subcarriers are selected to transmit data, a pseudorandom sequence is used for shifting of the subcarrier at each OFDM mark space, so that little signal bandwidth is increased, but the effects of rapid frequency hopping and anti-interception can be achieved simultanesouly. Under the interference of broadband, the scheme of random frequency hopping is adopted, at each OFDM mark space, a relatively small amount of subcarriers are randomly selected to transmit data, so that the signal to interference plus noise power ratio is improved, and the effect caused by broadband interference is lowered.
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Description

technical field

[0001] The invention relates to a frequency hopping anti-interception method in an OFDM system, belonging to the technical field of wireless communication. Background technique

[0002] Frequency hopping is a commonly used spread spectrum method in wireless communication. Its working principle is that the carrier frequency of the transmission signal of the transmitting and receiving parties changes discretely according to a predetermined rule. In terms of the implementation of communication technology, frequency hopping technology is a communication method that uses code sequences to perform multi-frequency frequency shift keying. From the perspective of signal spectrum, frequency hopping signals generally occupy a wide frequency band.

[0003] Commonly used frequency hopping code sequences are pseudo-random sequences designed based on m-sequences and RS codes. These pseudo-random code sequences are realized through a shift register plus a feedback structur...

Claims

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