A Multi-Frequency Microstrip-fed Annular-Slot Antenna

This note describes a multi frequency annular slot antenna. The design is based on the paper: “A Multi-frequency Microstrip-fed Annular Slot Antenna” by Hooman Tehrani and Kai Chang. The entire structure is defined parametrically to allow optimisation and parametric studies. The setup process in CST MICROWAVE STUDIO® takes about 10 to 15 min for an experienced user.

Design of the Annular Slot Antenna. To allow optimisation the entire structure is defined parametrically.
Figure 1: Design of the Annular Slot Antenna. To allow optimisation the entire structure is defined parametrically.

The substrate has a thickness of 0.762 mm and a dielectric constant of 2.45. The width of the 50 Ohm Microstrip line is 2.16 mm. All other dimesions can be found in following table. All values are in mm.

Parameter definition. All values are in mm
Figure 2: Parameter definition. All values are in mm

Calculation Results

The simulation results agree very well with the published results (Figure 3). Several slot resonances are excited. The simulated resonance frequencies are at 3.5 GHZ, 4.5 GHz and 6.5 GHz respectively.

Comparison of published and MWS Results.
Figure 3: Comparison of published and MWS Results.

Radiation Pattern at 3.5 GHz, 4.5 GHz and 6.5 GHz
Figure 4: Radiation Pattern at 3.5 GHz, 4.5 GHz and 6.5 GHz

CST Article "A Multi-Frequency Microstrip-fed Annular-Slot Antenna"
last modified 28. Feb 2008 10:42
printed 6. Jul 2015 7:45, Article ID 52

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