TABLE III.

Comparisons of computation times, input parameters, and time ratios that describe the reduction in the computation time achieved with the FNM and time-space decomposition relative to the exact and approximate impulse response for specified maximum errors of 10% and 1%. For FNM, impulse response, and FIELD II calculations with “use_triangles,” the transient results are evaluated in an 81×101-spatial point computed at 85 time points, and for the smoothed impulse response, the results are evaluated at the same temporal points in a restricted 81×86-point spatial grid.

	Transient Near-field computations
	10% peak error				1% peak error
	FNM	Impulse  response	FIELD II use_triangles	Smoothed impulse response	FNM	Impulse response	FIELD II use_triangles	Smoothed impulse response
Parameters	N=5	fs=128 MHz	fs=16 MHz	fs=32 MHz	N=9	fs=1 GHz	fs=64 MHz	fs=128 MHz
Time	0.4867 s	1.8911 s	5.3317 s	1.0122 s	0.6160 s	23.5241 s	6.8078 s	4.1261 s
Time ratio	1	3.89	10.95	2.08	1	38.19	11.05	6.70