What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?

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Multiple Choice

What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?

Shortening an antenna with loading coils raises its Q and narrows its bandwidth. The loading coil makes the antenna behave like a higher-Q resonant circuit, storing more energy relative to what is radiated. Since bandwidth is roughly inversely related to Q, a higher Q means the range of frequencies over which the antenna can efficiently operate becomes smaller. In practice, coil losses can further reduce usable bandwidth, but the main effect is the increased Q that tightens the bandwidth.

Shortening an antenna with loading coils raises its Q and narrows its bandwidth. The loading coil makes the antenna behave like a higher-Q resonant circuit, storing more energy relative to what is radiated. Since bandwidth is roughly inversely related to Q, a higher Q means the range of frequencies over which the antenna can efficiently operate becomes smaller. In practice, coil losses can further reduce usable bandwidth, but the main effect is the increased Q that tightens the bandwidth.

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