Half wave antennas are not ideal, they are merely easy to center-feed. Most portable devices use quarter wave antennas because they are easy to end-feed, and are half as long as half wave antennas. Five eighth wave antennas are improvements on quarter wave end-fed antennas in that they have somewhat better azimuthal gain than quarter wave, with slightly more complicated feed point circuitry. End-fed antennas longer than 5/8 wave actually have reduced azimuthal gain due to the presence of minor lobes.
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Half wave antennas are not ideal, they are merely easy to center-feed. Most portable devices use quarter wave antennas because they are easy to end-feed, and are half as long as half wave antennas. Five eighth wave antennas are improvements on quarter wave end-fed antennas in that they have somewhat better azimuthal gain than quarter wave, with slightly more complicated feed point circuitry. End-fed antennas longer than 5/8 wave actually have reduced azimuthal gain due to the presence of minor lobes.