Antenna Bandwith Expansion Guide
Method for bandwidth expansion for chip antennas:
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Layout with additional "elbow" to GND:
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(B) Detailed land pattern with dimensions (+ 2 variables)
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Return loss measurement (variables a and b dependent)
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Bandwidth Summary with PIFA type. Table-1
Case | New Bandwidth (S11) | Frequency Range |
---|---|---|
1 = 5mm, b=3.25mm, h-direction_1 PIFA | 220 MHZ | 2.32 ~ 2.54GHZ |
a=3mm, b=2.25mm h-direction_3 PIFA | 230MHz | 2.32 ~ 2.55GHz |