A magloopmagnetic loop antenna (magloop antenna for short) (example) can be a good choice for high efficiency in a small size if it is designed well. See more here: https://www.google.com/search?q=MagneticLoopAntenna and here: https://www.youtube.com/results?search_query=magloop
linking to a search query is utterly pointless, link to useful sources instead
