ANNA-B112 - System integration manual
UBX-18009821 - R09
Appendix
Page 61 of 66
C1-Public
B.4
Examples of application ground plane miniaturizations
The following boards are used as examples to show what’s possible when reducing board size. Since
the radiated power fluctuates when using a small ground plane, care must be taken to ensure a
sufficient range and radiated power for every application ground plane size. Range measurement in
a field, line of sight recommended, or measure the radiated power in an RF diagnostic chamber are
two ways to confirm antenna efficiency
.
B.4.1
Example application 1
The C8_1 board with ANNA-B1 module in the corner, mounted to the left as shown in Figure 3737 is
the first example that shows what can be achieved by shrinking the board size. The below graph
visualizes the correlation between the total radiated power, TRP, and the ground plane size. The C8_1
board represents the peak power of -5.67 dBm. It has a wavelength part of 0.75 in x-axis and 0.14 in
Y-axis corresponding to 46 mm and 8 mm respectively. Additionally, the TRP patterns of the C8_1
board illustrates a nice round even shape as shown in Figure 3939.
Figure 37: An example of ground plane miniaturization and still having a good range, about 250 m
Figure 38: The C8_1 board, TRP peak, can be found in the TRP graph where different board sizes in wave lengths are plotted
-5.67 C8_1
-12
-11
-10
-9
-8
-7
-6
-5
-4
0.40
0.60
0.80
1.00
1.20
1.40
1.60
TR
P (
dB
m
)
Wavelengths of 2440 MHz - x length
TRP vs. Antenna ground plane x wavelengths
