They are also widely used as driven elements for rooftop Yagi television antennas. UHF tags provide accurate readings with specially designed antennas. There are also mounting hardpoints for mobile radar antennas. Wireless communications (with exception to point-to-point radio links using directional antennas) are inherently broadcasting media. Such antennas are known as printed monopole antennas. One of only four GPS satellite ground antennas is located there. It consisted of a number of Yagi antennas. The Type 42 had more revisions, including a change to using four Yagi antennas. Beamforming can be accomplished using phased array antennas. Parabolic (dish) antennas are widely used. This makes them inefficient as transmitting antennas. The SHARAD radar antennas were deployed on September 16. This invention led to the development of radar, smart antennas, and MIMO. There is an electrical relationship defined by the distance between transmit and receive antennas. The ILS system is composed of 180 different transmitting antennas at each point built.