A wind turbine which is configured to be disposed in or above a sea floor is provided. The wind turbine includes a tower configured to protrude from a sea level and having a transmitter configured to transmit an electromagnetic wave to be reflected on the sea level and a receiver configured to receive the reflected electromagnetic wave, wherein at least one of the transmitter and the receiver includes a leaky feeder; and a processing unit being in communication with the receiver and configured to analyse the reflected electromagnetic wave such that a wave characteristic of the sea level is determined.

A wind turbine which is configured to be disposed in or above a sea floor is provided. The wind turbine includes a tower configured to protrude from a sea level and having a transmitter configured to transmit an electromagnetic wave to be reflected on the sea level and a receiver configured to receive the reflected electromagnetic wave, wherein at least one of the transmitter and the receiver includes a leaky feeder; and a processing unit being in communication with the receiver and configured to analyse the reflected electromagnetic wave such that a wave characteristic of the sea level is determined.

An apparatus including a leaky feeder arrangement including a plurality of parallel leaky feeders, a transmitter coupled to the leaky feeder arrangement and configured to supply individual first radar signals to a group of leaky feeders in the leaky feeder arrangement, the first radar signals being configured to form a first radar signal beam in a predetermined direction relative to the leaky feeder arrangement, a receiver coupled to the leaky feeder arrangement and configured to receive a second radar signal from the leaky feeder arrangement, wherein the second radar signal is reflected from the target object when the first radar signal beam hits the target object, and a processing unit configured to analyse a first signal corresponding to the first radar signals and a second signal corresponding to the second radar signal to determine the properties of the moving object. A wind turbine and a method are also provided.

A flight vehicle includes a drone with a pair of shaped protrusions mechanically coupled to the drone. One of the shapes is a hollow lift-producing shape, such as being a balloon filed with a lighter-than-air gas, and the other of the shapes is below the drone. The shape below the drone may be a hollow shape that does not produce lift, for example being a balloon filled with air. The shapes may be similar in size and shape, so as to provide similar drag characteristics. The shapes may be opposite ends of a support, such as a stick, rod, or other (relatively) slender structure. The vehicle includes a payload, such as radar calibration equipment or an antenna. The drone may be used to counteract wind forces on the flight vehicle, and/or to otherwise position the flight vehicle.

A flight vehicle includes a drone with a pair of shaped protrusions mechanically coupled to the drone. One of the shapes is a hollow lift-producing shape, such as being a balloon filed with a lighter-than-air gas, and the other of the shapes is below the drone. The shape below the drone may be a hollow shape that does not produce lift, for example being a balloon filled with air. The shapes may be similar in size and shape, so as to provide similar drag characteristics. The shapes may be opposite ends of a support, such as a stick, rod, or other (relatively) slender structure. The vehicle includes a payload, such as radar calibration equipment or an antenna. The drone may be used to counteract wind forces on the flight vehicle, and/or to otherwise position the flight vehicle.

Provided is a radar and communications enhanced sail for a sailboat, sail ship, or sail drone. The sail includes a first sail section comprising an active communication system, a second sail section comprising a passive communication system, or a combination thereof. The active communication system includes an antenna array (transceiver) and a software-defined radio (SDR), while the passive communication system comprises a reflective panel or sections and/or array of reflector panels or sections. The active system utilizes its SDR and transceiver to communicate back and forth with an onshore SDR and transceiver to provide information as necessary. The passive system receives a radar signal via the reflective material on the sail and reflects the signal back at the radar, which produces a radar cross section indicating that there is an object (in this case the sailboat) in the ocean.

The antenna system and the method receive signals having radio frequencies in a plurality of radio frequency bands. The antenna system includes a support assembly, a primary reflector that is coupled to the support assembly, a feed assembly that is movably coupled to the support assembly, and a first feed and a second feed fixedly coupled to the feed assembly. The first feed and the second feed are configured to communicate RF signals in a first frequency band and a second frequency band, respectively, of the plurality of frequency bands. The antenna system also includes a first actuator that is configured to move the feed assembly from a first feed assembly position, where the first feed is positioned along a first signal path with the primary reflector, to a second feed assembly position, where the second feed is positioned along a second signal path with the primary reflector.

The antenna system and the method receive signals having radio frequencies in a plurality of radio frequency bands. The antenna system includes a support assembly, a primary reflector that is coupled to the support assembly, a feed assembly that is movably coupled to the support assembly, and a first feed and a second feed fixedly coupled to the feed assembly. The first feed and the second feed are configured to communicate RF signals in a first frequency band and a second frequency band, respectively, of the plurality of frequency bands. The antenna system also includes a first actuator that is configured to move the feed assembly from a first feed assembly position, where the first feed is positioned along a first signal path with the primary reflector, to a second feed assembly position, where the second feed is positioned along a second signal path with the primary reflector.

An apparatus includes a cross-link phased array and a communication-link phased array. The cross-link phased array and the communication-link phased array are integrated into a single array. The cross-link phased array and communication-link phased array comprise a multi-beam phased array. The cross-link phased array provides communication between multiple space vehicles and the communication-link phased array provides communication between the satellite and the ground GPS system.

An apparatus includes a cross-link phased array and a communication-link phased array. The cross-link phased array and the communication-link phased array are integrated into a single array. The cross-link phased array and communication-link phased array comprise a multi-beam phased array. The cross-link phased array provides communication between multiple space vehicles and the communication-link phased array provides communication between the satellite and the ground GPS system.