Signal modulation method based on weighted-type fractional Fourier transform and energy spreading transform

A fractional Fourier and energy expansion technology, applied in the field of signal modulation based on weighted fractional Fourier transform and energy expansion transform, can solve problems such as poor anti-interception effect
CN103441822AActive Publication Date: 2013-12-11HARBIN INST OF TECH +1
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Patent Information

Authority / Receiving Office
CN · China
Current Assignee / Owner
HARBIN INST OF TECH
Publication Date
2013-12-11

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Abstract

The invention relates to a signal modulation method applied to the field of anti-interference and secure communication and discloses a signal modulation method based on weighted-type fractional Fourier transform and energy spreading transform, to solve the problem that a signal interception party adopts WFRFT (weighted-type fractional Fourier transform) and transform order tracking is relatively accurate, the anti-interception effect is poor when variable-parameter mixed carrier signals of multi-parameter fractional Fourier transform are adopted. The signal modulation method comprises the following steps of: 1, establishing an energy spreading transform matrix; 2, performing multistage tandem weighted-type fractional Fourier transform and pseudo-random interleaving process at a sending end; 3, processing a modulated sequence x through a channel cancellation technology (such as channel equalization, channel coding and decoding technologies and the like) to obtain a signal y to be modulated, and performing inverse transform on the signal y to be modulated by a signal receiving end to realize a demodulation process and restore an estimated value of a source information sequence. The signal modulation method disclosed by the invention is applied to the field of secure communication.
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Description

technical field

[0001] The invention relates to a signal modulation method applied in the fields of anti-interference and secret communication. Background technique

[0002] In a communication system that requires confidentiality and anti-interference, it is usually required that the communication signal is not easy to be detected or intercepted by a third party, and at the same time be resistant to channel distortion and signal distortion. Therefore, how to design a wireless signal that meets the two requirements is very important in this communication system. Existing methods to achieve anti-detection and anti-interception by changing the characteristics of the source signal at the signal waveform level mainly include spread spectrum (such as frequency hopping) technology, based on multi-parameter weighted-type fractional Fourier transform (WFRFT) Mixed carrier modulation and modulation methods combining the above two technologies, etc. In recent years, detection and tra...

Claims

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