A Channel Precise Synchronization Method for Navigation-Decoy Signal Synthesis

Abstract

The invention discloses a channel accurate synchronization method for navigation decoy signal synthesis. The method is used for realizing strict synchronization of satellite navigation decoy signals,including precise synchronization of baseband components in single-channel signals and precise synchronization among multiple channels, and comprises the following steps: 1) constructing a baseband signal synthesis channel, and indexing low-speed components by using high-speed baseband components to ensure that the baseband components are strictly aligned in a time domain; 2) measuring to obtain the inconsistency between the channels, calculating to obtain the signal phase difference between the channels by measuring the ratio of the power of the inverted dual-channel synthetic signal to the power of the single-channel signal, and further converting the signal phase difference into the time difference corresponding to the inconsistency of the channel pipelines; and 3) according to the timedifference of signal generation of each channel, calculating in a digital domain to obtain offset values of each baseband component phase and carrier phase of the corresponding navigation decoy signal, and performing synchronous compensation on each channel. Channel inconsistency can be improved from a nanosecond level to a picosecond level, and the quality of the decoy signal is greatly improved.

Description

technical field [0001] The invention relates to a precise channel synchronization method for synthesizing navigation decoy signals, which is suitable for ensuring strict synchronization of baseband components of decoy signals, eliminating baseband burrs, and effectively reducing the synchronization errors between channels by measuring and compensating the synchronization errors between channels. Background technique [0002] In recent years, the number of unmanned aerial vehicles has shown explosive growth, and incidents of black flying have emerged one after another, posing a huge threat to urban security and military security. At present, UAV countermeasures mainly include suppressive jamming, protocol cracking, fire damage, and navigation deception. Among them, the navigation deception method induces the UAV to lock the pseudo-satellite navigation signal, and indirectly controls the UAV by sending dynamic information such as false position and speed. Uncontrollable risk ...

AI Technical Summary

Problems solved by technology

[0027] 1) The clock source used by each signal synthesis channel is the same, but the length of the FPGA clock pipeline is different, so there must be some inconsistency in the clock used by the logic processing unit of each channel;

[0028] 2) The wiring lengths between the internal logic units of each signal synthesis channel on the FPGA used for digital signal synthesis are not exactly the same, resulting in a maximum synchronization error of sub-nanosecond or even nanosecond level

The disadvantage is that it will introduce the channel inconsistency and calculation error of the receiver itself

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