GEMS PC v.s. GPU
 
We compare the two regular PCs installed with Windows Vista and GEMS software 6.0 with the GPU workstation installed with other commercial FDTD software for a cell phone model simulation. The number of unknowns (6.4Mcells), excitation source type (lumped port), output parameters (far field pattern at 2 frequencies) are same in the simulations of GEMS PC and GPU workstation. Two GEMS PCs, which are directly connected each other by a 3-meter long regular network cable, are much faster than the GPU workstation. The two computers (their total cost is about US$2000.00) can be used as the general purpose when they are not used for the GEMS simulation.
 

GEMS Simulation Settings

Memory
usage
Absorbing boundary
Parallel processing
Excitation
source
Convergence criterionMinimum
cell size (mm)		Number of
time steps
351 MB
6-layer CPML
MPI/OpenMP
Lumped port
-30 dB
(0.5, 0.4, 0.5)
15,465
 
Model Information
 
Model
CAD file size
Phone case
Cover
Screen
AntennaPCB
SAT
1.334 MB
Dielectric (3.0)
Dielectric (2.8)
PEC
Copper
FR4
 
 
 
GEMS PC Platform
Processor
Memory
OS
GEMS Software
Cost
Intel i7-860 2.8GHz
4GB DDR3 1333MHz
Windows Vista
GEMS v6.0
US$1k
 
Comparison of GEMS PC and Other Commercial FDTD GPU workstation
 
Hardware platform
Simulation time
Problem size
Outputs
Single PC
(Intel i7-860 2.8GHz)
(cost: US$1k)
44 min. 46 sec.
(Pre-processing: 4 min. 44 sec.
+ Simulation: 40 min. 2 sec.)
118 x 451 x 120
(6.5 Mcells)
(1) Return loss;
(2) Far field patterns at 2 frequencies
GPU workstation
(cost: US$17k)
58 min. 26 sec.
(39min.43 sec. (Broadband)
+ 18 min. 43 sec. (harmonic) )
6.4 Mcells
(1) Return loss;
(2) Far field patterns at 2 frequencies
 
 
 

GEMS Two-PC Acceleration Platform

 
Hardware platform
Simulation time
Problem size
Outputs
Two PCs
(Intel i7-860 2.8GHz)
(cost: US$2k)
25 min. 37 sec.
(Pre-processing: 2 min. 30 sec.
+ Simulation: 23 min. 7 sec.)
118 x 451 x 120
(6.5 Mcells)
(1) Return loss;
(2) Far field patterns at 2 frequencies
GPU workstation
(cost: US$17k)
58 min. 26 sec.
(39min.43 sec. (Broadband)
+ 18 min. 43 sec. (harmonic) )
6.4 Mcells
(1) Return loss;
(2) Far field patterns at 2 frequencies