A whip antenna is a single-element antenna that can be used with anunbalanced feed line such as coaxial cable,or attached directly to a wirelesstransmitter, receiver, or transceiver. The whip resembles a ground-plane antenna without the radial system.The short, flexible "rubber duck" antennas found on handheld two-wayradios and cell phones are examples of whip antennas. So are the long, flexible,stainless-steel antennas used in Citizens Band mobile installations. Some portablewhip antennas can be telescoped down to a length of only few inches for transport andstorage, and extended to several feet for operation.
Assets of the whip antenna include electrical and mechanical simplicity. Littleor no installation is necessary. But, because most whip antennas are operated with apoor electrical ground system, they are usually inefficient. A whip directlyconnected to a transmitter radiates radio-frequency (RF) energy into the immediateoperating environment. This may cause nearby electronic apparatus (including medicaldevices) to malfunction. Whip antennas used with handheld radios and cell phonessubject the human body, especially the head and hands, to strong electromagnetic fields. This has givenrise to uncertainty about the biological safety of whip antennas directly connected to handheld transceivers.
In high-powered or long-range wireless communications, substantial outdoor antennas,used with well-engineered feed systems, work much better than whip antennas. Inaddition, when a transmitting antenna is placed at a distance from humans and electronicequipment, the potential electromagnetic hazard is minimized.