Wireless Network Antenna Card
Abstract:An antenna card used for connecting a laptop PC to a wireless network is designed using FDTD simulation technology in EMPro. Includes measured and simulated results.This example demonstrates the use of FDTD technology in EMPro for the design of a wireless network card antenna. The ultra-fast simulation capability of EMPro enables designers to quickly test and verify different antenna configurations and sizes. EMPro’s powerfull visualization features also enable designers to analyze the current and field patterns on the antenna surface which aids the design of smaller antennas.
Some laptop PCs use external wireless networking cards for connecting to a cellular network. Since the antenna performance is critical to the overall system performance, the antenna must be properly designed, while size is minimized.
Figure 1: Typical network card antenna configuration
One design issue is that the size of the ground plane affects the resonance frequency of antenna, so antenna designers must analyze the antenna with ground planes attached as shown in Figure 2.
Figure 2: EM simulations showing effect of ground plane size on resonant frequency
Another issue to consider is whether the presence of localizer will change the antenna’s resonance frequency and the current distribution. Figure 3 shows little effect of a localizer in this case.
Figure 3: Simulation results with and without a localizer
The figures below show results from FDTD simulations in EMPro.
Figure 4: Far field patterns at two frequencies
Figure 5: Current and field plots
Figure 6: Comparison of different antenna heights
Figure 7: Simulated and measured return loss results
With EMPro, the design of a wireless network card antenna is simple and quick. The ultra fast simulation capability of EMPro enables you to quickly test and verify different antenna configurations and sizes.