AN3359

4/28

Doc ID 018585 Rev 1

Figure 1.

Spherical coordinate system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Figure 2.

Layout of Meander-like PCB antennae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Figure 3.

Cross section of the PCB at antennae region. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Figure 4.

Part of the ZigBee module's PCB with Meander-like antenna (around scale 4:1) . . . . . . . . 8

Figure 5.

Bypassing impedance matching circuitry - direct RF connection . . . . . . . . . . . . . . . . . . . . . 8

Figure 6.

Complex impedance of the Meander-like antenna on Smith Chart . . . . . . . . . . . . . . . . . . . 9

Figure 7.

Magnitude of the S11 parameter in logarithmic scale (Cartesian plot) . . . . . . . . . . . . . . . . 10

Figure 8.

Antenna's Standing Wave Ratio (SWR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Figure 9.

Three dimensional (3-D) radiation pattern overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Figure 10.

Radiation pattern on Y-Z plane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Figure 11.

Radiation pattern on X-Z plane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Figure 12.

Major planes used to visualize 3-D radiation pattern using 2-D plots . . . . . . . . . . . . . . . . . 15

Figure 13.

Far field radiation pattern plotted on Y-Z plane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Figure 14.

normalized radiation pattern on Y-Z plan (Polar plot) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Figure 15.

normalized radiation pattern on Y-Z plane (Cartesian plot)) . . . . . . . . . . . . . . . . . . . . . . . . 18

Figure 16.

Far field radiation pattern plotted on X-Y plane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Figure 17.

Normalized radiation pattern on X-Y plan (Polar plot) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure 18.

Normalized radiation pattern on X-Y plan (Cartesian plot) . . . . . . . . . . . . . . . . . . . . . . . . . 21

Figure 19.

Far field radiation pattern plotted on X-Z plane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Figure 20.

Normalized radiation pattern on X-Z plane (Polar plot). . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Figure 21.

Normalized radiation pattern on X-Z plane (Cartesian plot) . . . . . . . . . . . . . . . . . . . . . . . . 24