Low-Complexity Spatial-Temporal Filtering Method via Compressive Sensing for Interference Mitigation in a GNSS Receiver

Table 2

Complexity comparison of STAP algorithms in different update procedures.

Algorithm	Evaluation factors	Intermediate Con-strained matrix	Update weight vector	Total complexity	Computation load (per snapshot)
Reduced-rank PM	MUX	𝑁𝐸𝐽+𝐽^2+𝐽	𝑁𝐸𝐽^2+𝑁𝐸𝐽+𝐽	𝑁𝐸𝐽^2+2𝑁𝐸𝐽+𝐽^2+2𝐽	𝑂[𝑁𝐸𝐽]
	ADD	3𝑁𝐸𝐽−2𝑁𝐸+𝐽^2−1	3𝑁𝐸𝐽−𝑁𝐸−𝐽−1	6𝑁𝐸𝐽−3𝑁𝐸+𝐽^2−𝐽−2
	MEM	2𝑁𝐸	2𝑁𝐸+𝑁𝐸𝐽+𝐽	𝑁𝐸𝐽+4𝑁𝐸+𝐽
MSNWF	MUX	𝑁𝐸𝐽+𝐽	𝑁𝐸𝐽+2𝐽	2𝑁𝐸𝐽+3𝐽	𝑂[𝑁𝐸𝐽]
	ADD	𝑁𝐸𝐽	𝑁𝐸𝐽+2𝐽	2𝑁𝐸𝐽+2𝐽
	MEM	𝑁𝐸	𝑁𝐸+2	2𝑁𝐸+2
MVDR	MUX	3𝑁𝐸	3(𝑁𝐸)^3+(𝑁𝐸)^2	3(𝑁𝐸)^3+(𝑁𝐸)^2+3𝑁𝐸	𝑂(𝑁𝐸)^3
	ADD	2(𝑁𝐸)^2−2𝑁𝐸	3(𝑁𝐸)^3−2(𝑁𝐸)^2−𝑁𝐸	3(𝑁𝐸)^3−3𝑁𝐸
	MEM	(𝑁𝐸)^2+𝐸^2	𝑁𝐸	(𝑁𝐸)^2+𝐸^2+𝑁𝐸
C-MVDR	MUX	3𝑃𝑄	3(𝑃𝑄)^3+(𝑃𝑄)^2	3(𝑃𝑄)^3+(𝑃𝑄)^2+3𝑃𝑄	𝑂(𝑃𝑄)^3
	ADD	2(𝑃𝑄)^2−2𝑃𝑄	3(𝑃𝑄)^3−2(𝑃𝑄)^2−𝑃𝑄	3(𝑃𝑄)^3−3𝑃𝑄
	MEM	(𝑃𝑄)^2+𝑄^2	𝑃𝑄	(𝑃𝑄)^2+𝑄^2+𝑃𝑄