An Anti-Jamming Null-Steering Control Technique Based on Double Projection in Dynamic Scenes for GNSS Receivers

Area of Science:

• Signal Processing
• Aerospace Engineering
• Electrical Engineering

Background:

• Global Navigation Satellite System (GNSS) receivers face performance degradation in dynamic environments due to rapidly changing interference signal arrival directions.
• Spatial filtering nulls, crucial for anti-jamming, widen and shallow under dynamic interference, diminishing their effectiveness.
• Existing methods struggle to maintain optimal anti-jamming performance when interference direction changes rapidly.

Purpose of the Study:

• To address the deterioration of anti-jamming performance in GNSS receivers operating in dynamic scenes.
• To propose and validate a novel null-steering control technique to enhance spatial filtering capabilities.
• To significantly increase the depth of spatial filtering nulls against rapidly moving interference.

Main Methods:

• Established a dynamic model characterizing the relationship between interference and the GNSS receiver.
• Analyzed the rate of change of interference arrival direction based on the dynamic model.
• Introduced and applied a dual projection algorithm for null-steering control to deepen spatial filtering nulls.

Main Results:

• Simulated and verified the phenomenon of spatial filtering nulls widening and shallowing in dynamic scenarios.
• The proposed dual projection algorithm effectively deepened the spatial filtering nulls.
• Demonstrated an increase in null depth by 30 to 50 dB, significantly boosting anti-jamming capabilities.

Conclusions:

• The dual projection algorithm offers a robust solution for improving GNSS anti-jamming performance in dynamic environments.
• This technique effectively counteracts the detrimental effects of rapidly changing interference arrival directions.
• The substantial increase in null depth translates to significantly enhanced resilience and reliability of GNSS receivers.