Techniques that facilitate reconfigurable transmission of a radar frequency signal are provided. In one example, a system includes a signal generator and a power modulator. The signal generator provides a radar waveform signal from a set of radar waveform signals. The power modulator divides a local oscillator signal associated with a first frequency and a first amplitude into a first local oscillator signal and a second local oscillator signal. The power modulator also generates a radio frequency signal associated with a second frequency and a second amplitude based on the radar waveform signal, the first local oscillator signal and the second local oscillator signal.

Methods and devices for estimating an angle between a transmitter and a receiver for beamforming are provided. A method includes, with an antenna element in a first device, transmitting an omnidirectional pulse and detecting an echo of the pulse reflected from a second device. An angle between the first device and the second device is estimated based at least on a characteristic of the echo. The method includes transmitting the angle to the second device for use in beamforming between the first device and the second device.

Methods, systems, and devices for radar signaling s are described. In some systems, devices may select radar parameters (e.g., frequency modulated continuous wave waveform parameters) to support coexistence for multiple radar sources in the system. To reduce mutual interference between radar waveforms in a system, a user equipment may detect interference from at least one interference source (e.g., another device transmitting a radar waveform) and may select waveform parameters for transmission of a radar waveform based on the detected interference. For example, the user equipment may determine slopes, frequency offsets, codewords, or a combination thereof used by nearby devices in the system (e.g., per chirp or for a waveform) and may select waveform parameters that result in low mutual interference with the determined slopes, frequency offsets, codewords, or combination thereof. The user equipment may transmit the radar waveform according to the selected waveform parameters.

Provided is a code allocating apparatus including an interference signal measurer configured to measure interference signals, an interference signal sharer configured to control radars to share the measured interference signals between the radars, a code allocator configured to dynamically allocate a code generated based on the measured interference signals to each of the radars, and a code applier configured to apply the code to each of the radars.

A radar device includes radar transmission and receiving circuits. The radar transmission circuit transmits one or more transmission signals, each having a transmission period Tr. The radar receiving circuit receives one or more reflected signals in which the transmission signals are reflected by an object and estimates a direction of the object based on the reflected signals. The radar transmission circuit includes Nt transmission antennas. A control circuit sets a transmission gap period between a first and second periods, with the transmission gap period being a period during which the transmission signals are not transmitted. The first period is equal to an integral multiple of a period Np, the period Np is equal to or more than Nt times the transmission period Tr, and the second period is set after the first period and is equal to an integral multiple of the period Np.

A method for measuring a separation distance to a target object using a communication signal includes transmitting from a first device, via a transmitter of the first device, a communication signal including a first bit pattern encoded therein. The method also includes receiving, via a processor on the first device, a copy of the communication signal prior to encoding and receiving, via a receiver of the first device, an echo based on the transmitted communication signal. The received echo is decoded and the method includes identifying, via the processor, the first bit pattern in the copy of the communication signal and identifying, via the processor, the first bit pattern in the decoded echo. Then the method determines, via the processor, a time of flight of the first bit pattern based on identifying the first bit pattern in each of the copy of the transmitted communication signal and in the received echo, and performs, via the processor, an action based on the determined time of flight.

Apparatus and methods are presented for characterising the environment of a user platform. In certain embodiments RF signals are transmitted and received through an antenna array having a plurality of elements activated in a predetermined sequence, and received signals are manipulated with round-trip path corrections to enhance the gain of the array in one or more directions. Objects in those directions are detected from the receipt of returns of transmitted signals, and the manipulated received signals processed to estimate range to those objects. In other embodiments RF signals transmitted by one or more external transmitters are received and manipulated to enhance the gain of a local antenna array or antenna arrays associated with the one or more transmitters to enhance the gain of the arrays in one or more directions. Objects in those directions are detected from the receipt of reflected signals from the transmitters, and the manipulated received signals processed to estimate range to those objects.

A method and apparatus for processing global navigation satellite signals, or radar signals, specifies an arrival time of a signal having a shape similar to a known pseudo-random noise sequence (PRN) of rectangular pulses. Two quadrature signals are generated and six correlations are calculated and multiplied by a correlation coefficient. The results of one of quadrature signals are summed and a timing error is estimated. An improved signal arrival time is generated by adding the estimated timing error to the predicted signal arrival time is generated.

Disclosed is a method and apparatus for generating a radar signal, in which performance of radar detection is ensured while increasing a spectrum efficiency in a radar network. The method comprises generating a set of frequency-modulation waveforms, generating an orthogonal code set, generating a set of coded frequency-modulation waveforms through element operation between the set of frequency-modulation waveforms and the orthogonal code set, calculating an objective function for the set of frequency-modulation waveforms with regard to a different set of coded frequency-modulation waveforms and previous sets of coded frequency-modulation waveforms, and selecting a current polyphase code set as an optimized polyphase code set when a result of current calculation is better or smaller than a result of previous iteration, and performing phase perturbation by replacing an element randomly selected in the current polyphase code set selected as the optimized polyphase code set with another admissible-phase element.

In an example method, a vehicle configured to operate in an autonomous mode could have a radar system used to aid in vehicle guidance. The method could include transmitting at least two signal pulses. The method further includes, for each transmitted signal pulse, receiving a reflection signal associated with reflection of the respective transmitted signal pulse. Each reflection signal may be received when the apparatus is in a different respective location. Additionally, the method includes processing the received reflection signals to determine target information relating to one or more targets in an environment of the vehicle. Also, the method includes correlating the target information with at least one object of a predetermined map of the environment of the vehicle to provide correlated target information. Yet further, the method includes storing the correlated target information for the at least one object in an electronic database.