A radar transmitter transmits a radar signal through a transmitting array antenna at a predetermined transmission period, and a radar receiver receives a reflected wave signal which is the radar signal reflected by a target through a receiving array antenna. A transmitting array antenna and a receiving array antenna each include multiple subarray elements, the subarray elements in the transmitting array antenna and the receiving array antenna are linearly arranged in a first direction, each subarray element includes multiple antenna elements, the subarray element has a dimension larger than a predetermined antenna element spacing in the first direction, and an absolute value of a difference between a subarray element spacing of the transmitting array antenna and a subarray element spacing of the receiving array antenna is equal to the predetermined antenna element spacing.

The present invention relates to a radar device for a vehicle which may determine a target as a single target or multiple targets according to a dispersion level of a slope for each reception channel, calculated through a phase difference for each reception channel of a reflection signal and an arrangement interval for each reception channel, and estimate the angle of the target so as to acquire the angle of the target using a small amount of calculations, and a method for estimating the angle of a target using the same. An embodiment of the present invention provides a radar device for a vehicle, which detects a target located in the front side of a vehicle, comprising an electronic control unit configured to: calculate the slope of a reflection signal received for each reception channel, using a phase difference for each reception channel of the reflection signal and an arrangement interval for each reception channel, wherein the reflection signal is obtained by transmitting a predetermined transmission signal and receiving the transmitted transmission signal which is reflected back from the target; and determine the target as a single target or multiple targets according to a dispersion level of the calculated slope so as to estimate the angle to the determined target.

An integrated photonics monopulse comparator includes an array of squinted monopulse elements, each monopulse element producing an RF signal in response to a received inbound signal and each RF signal having a squinted RF voltage. The comparator includes a laser source for producing a wavelength division multiplexed (WDM) optical signal comprising multiple components having discrete wavelengths. The component signals may be multiplexed and demultiplexed and routed through cascading optical phase modulators, each phase modulator connected to a monopulse element and capable of modulating a component signal according to the voltages of the RF signals produced by the corresponding monopulse element. The resulting modulated component optical signals undergo coherent photodetection by arrays of paired photodiodes, each pair receiving component signals of like wavelength. The output signals of each array are proportional in voltage to sums and differences from which arrival angles of the inbound signal may be calculated.

In an embodiment, an antenna subsystem includes a sparse receive antenna and an electronically steerable transmit antenna. The sparse receive antenna includes an array of receive elements each configured to receive a respective signal having a wavelength and each spaced apart from each adjacent one of the receive elements by a respective first distance that is more than one half of the wavelength. And the electronically steerable transmit antenna includes an array of transmit elements each configured to radiate a respective signal having the wavelength and each spaced apart from each adjacent one of the transmit elements by a respective second distance that is less than one half of the wavelength. To reduce aliasing, such an antenna subsystem can be operated to filter, spatially, a receive beam pattern generated by the receive antenna with a transmit beam pattern generated by the transmit antenna.

The present invention is directed to an antenna system and a method that is configured to compute calibration element voltage gain patterns as functions of a digital antenna model and a plurality of complex beamformer voltages, determine calibration through path transfer functions from the plurality of complex voltages, and remove the calibration element voltage gain patterns from the calibration through path transfer functions to determine a beamforming network transfer function. The beamforming network transfer function and the far-field element voltage gain patterns are combined to obtain a system transfer function used to revise a calibration table.

An angle estimating method applied in a radar system. The radar system includes a first antenna array including M antennas. The angle estimating method includes steps of obtaining a plurality of beamforming weighting vectors; receiving signal from M antennas and forming a received vector; performing an augment operation on the received vector and obtaining an augmented received vector; computing correlation between the augmented received vector and the plurality of beamforming weighting vectors and obtaining a plurality of results accordingly; and determining an angle-of-arrival of an object according to the plurality of results.

Examples disclosed herein relate to a system of object detection, the system including a continuous modulation signal unit to generate a continuous modulation signal, a code generation unit to sample, quantize and encode the continuous modulation signal to generate an encoded signal, a transmit antenna to transmit the encoded signal, and a receive antenna to receive a reflection of the encoded signal and separate the reflection of the encoded signal from other signals.

A distributed directional aperture (DDA) system provides the capability to receive and/or transmit signals, limiting that reception or transmission to a 3-dimensional beam. The DDA system includes sensing and/or emitting array subsystems which comprise sensors and/or emitters distributed across, within, or under the skin of an aircraft, ship, ground vehicle, or fixed installation. The sensors receive energy, convert the received signals to digital information, and transmit that information via a telemetry subsystem to a beamformer subsystem. The beamformer subsystem analyzes the received signals from the sensors and/or emitters in order to determine the signal content from a specific direction. The emitters transmit energy, converting signals received from the beamformer subsystem via the telemetry subsystem into energy emissions. Methods of providing the DDA system including subsystems thereof are also disclosed.

A hazardous fire detection radar system that may be mounted on a vehicle, such as an aircraft to detect bullets, grenades and similar projectiles that may pose a danger to the vehicle. The system may observe a wide field-of-regard (FOR) and for each projectile, determine the range of closest approach to the host platform (miss distance) and an approximate direction of origin. The FMCW radar system measures range and Doppler information for targets within its FOR and resolves Doppler ambiguity by estimating angular information (azimuth and elevation) for each target projectile. The system may estimate angular information by using a monopulse antenna pattern with the radar receiver.

A radar comprises at least one array antenna composed of transmit sub-arrays and of receive sub-arrays, a transmit and receive system and processing means: the distribution of the transmit sub-arrays and receive sub-arrays is symmetric both with respect to a vertical axis and a horizontal axis; at least two transmit sub-arrays symmetric with respect to the vertical axis are the largest possible distance apart; at least two transmit sub-arrays symmetric with respect to the horizontal axis are the largest possible distance apart; at least two receive sub-arrays symmetric with respect to the vertical axis are the largest possible distance apart; at least two receive sub-arrays symmetric with respect to the horizontal axis are the largest possible distance apart; a first coding of the wave transmitted by the transmit sub-arrays carried out by frequency shifting of the ramps between the various transmit sub-arrays; a second coding of the wave transmitted by the transmit sub-arrays carried out by phase modulation from frequency ramp to frequency ramp between the various transmit sub-arrays.