BACKGROUND

Radio detection and ranging (RADAR) systems can be used to actively estimate range, angle, and/or Doppler frequency shift to environmental features by emitting radio signals and detecting returning reflected signals. Distances to radio-reflective features can be determined according to the time delay between transmission and reception. The radar system can emit a signal that varies in frequency over time, such as a signal with a time-varying frequency ramp, and then relate the difference in frequency between the emitted signal and the reflected signal to a range estimate. Some systems may also estimate relative motion of reflective objects based on Doppler frequency shifts in the received reflected signals.

In some examples, directional antennas can be used for the transmission and/or reception of signals to associate each range estimate with a bearing. More generally, directional antennas can also be used to focus radiated energy on a given field of view of interest. Combining the measured distances and the directional information allows for the surrounding environment features to be mapped. In other examples, non-directional antennas can be alternatively used. In these examples, a receiving antenna may have a 90 degree field of view, and may be configured to utilize multiple channels with a phase offset to determine angle of arrival of the received signal. Thus, the radar sensor can be used, for instance, by an autonomous vehicle control system to avoid obstacles indicated by the sensor information. Some example automotive radar systems may be configured to operate at an electromagnetic wave frequency range of 76-77 Giga-Hertz (GHz). These radar systems may use transmission antennas that can to focus the radiated energy into tight beams in order to enable receiving antennas (e.g., having wide angle beams) in the radar system to measure an environment of the vehicle with high accuracy.

SUMMARY

In one example, a radar system is provided. The radar system includes a radar unit configured to transmit a radar signal and receive radar reflections. The radar system also includes a memory configured to store data related to an environment. The radar system also includes a radar processing system. The radar processing system is configured to receive a location of a plurality of objects in the environment. The radar processing system is also configured to track a plurality of reflecting objects in the environment based on the received reflections. The radar system is further configured to determine that a received radar reflection corresponds to one of the plurality objects in the environment having an incorrect location. Additionally, the radar system is configured to revise a tracking for the one of the plurality objects in the environment having an incorrect location.

In another example, a method is provided that includes transmitting a radar signal by a radar system. The method also includes receiving reflections of the radar signal from an environment by the radar system. Additionally, the method includes receiving a location of a plurality of objects in the environment by a radar processing system. The method further includes tracking a plurality of reflecting objects in the environment based on the received reflections by the radar processing system. Yet further, the method includes determining, by the radar processing system, that a received radar reflection corresponds to one of the plurality objects in the environment having an incorrect location. Moreover, the method includes revising a tracking for the one of the plurality objects in the environment having an incorrect location.

In yet another example, a non-transitory computer readable medium having stored thereon executable instructions that, upon execution by a computing device, cause the computing device to perform functions is provided. The functions include causing the transmission of a radar signal by a radar system. The functions also include receiving reflections of the radar signal from an environment by the radar system. Additionally, the functions include receiving a location of a plurality of objects in the environment by a radar processing system. The functions further include tracking a plurality of reflecting objects in the environment based on the received reflections by the radar processing system. Moreover, the functions include determine that a received radar reflection corresponds to one of the plurality objects in the environment having an incorrect location by the radar processing system. The functions also include revising a tracking for the one of the plurality objects in the environment having an incorrect location.

In still another example, a system is provided that includes a means for transmitting a radar signal by a radar system. The system also includes a means for receiving reflections of the radar signal from an environment by the radar system. Additionally, the system includes a means for receiving a location of a plurality of objects in the environment by a radar processing system. The system further includes a means for tracking a plurality of reflecting objects in the environment based on the received reflections by the radar processing system. Yet further, the system includes a means for determining that a received radar reflection corresponds to one of the plurality objects in the environment having an incorrect location. Moreover, the system includes a means for revising a tracking for the one of the plurality objects in the environment having an incorrect location.

These as well as other aspects, advantages, and alternatives, will become apparent to those of ordinary skill in the art by reading the following detailed description, with reference where appropriate to the accompanying figures.

