Abstract: A radar responder for transmitting an electric wave signal which sweeps a predetermined frequency deviation width including the reception frequencies of the searcher's radar a plurality of times, responding to the pulse-modulated radar signal from the searcher's radar. The responder is provided with a high frequency FM modulator having said frequency deviation width, generates a radar responding signal which repeats said sweeps a predetermined number of times with a predetermined period, and a distinction signal for distinguishing individual radar responder which repeats said sweeps with said period in a predetermined pattern.

Abstract: A small-size transmitting apparatus for search and rescue operation (SARTR) adapted to be worn by a user for emitting a microwave rescue signal upon a marine accident involving the user. The SARTR includes a power supply, a transmitter unit energizable by the power supply and having a microwave oscillator, a transmitting antenna receiving of a microwave output from the transmitter unit for emitting the microwave rescue signal, a case accommodating the power supply, the transmitter unit, and the transmitting antenna and attachable directly to the user's body, or mountable on clothing or the like worn by the user for being carried thereby, and a switch unit mounted in the case for controlling the emission of the microwave rescue signal.

Abstract: A life buoy equipped with a radar responder adapted to transmit waves in response to radar waves from a searcher, the life buoy comprising a hull member of a rigid plastic hollow construction, the hull member water-tightly accommodating a receiving antenna, a receiver, a transmitting antenna, a transmitter and a battery in a vertical manner such that the center of gravity is located at a distance from and below the center of buoyancy, and the hull member having a downwardly converging shape from under the level of water at least up to the center of buoyancy.

Abstract: A radar beacon apparatus comprises a slot antenna for transmitting and a slot antenna for receiving which are respectively disposed in the substantially same axial direction and a transmitting unit and a receiving unit which are respectively connected to each end in the axial direction of the slot antenna as body parts. The body part is outwardly covered with a radar dome case made of a transparent sphere of waves (radio permeable material).

Abstract: A radar beacon apparatus to be used in conjunction with a search radar during emergency rescue operations. The radar beacon apparatus includes a receiving unit for receiving and detecting a radar pulse wave; a gate signal generating unit for generating upon the detection of a radar pulse wave a gate signal having a specific time interval; a transmitting unit for transmitting a frequency modulated signal which linearly and repetitively changes frequency over a predetermined frequency band during the time interval of the gate signal; and a display unit for displaying the reception of a radar pulse wave. The frequency sweep of the FM signal transmitted by the radar beacon completely covers and overlaps the receiver bandwidth of a comparable search radar, with each beacon transmission having an identical phase and frequency characteristic with respect to prior beacon transmissions.