Automotive radar interference mitigation by reconstruction and cancellation of interference component

Abstract

Automotive radar interference is an issue arising with the increasing amount of radar systems in automotive scenarios. Interference can influence the functionality of a radar system, e.g. decrease its detection capability. To ensure functionality in critical situations, interference countermeasures are applied. This paper proposes a countermeasure for chirp sequence modulated radars interfering one another estimating an interfering signals' parameters to afterwards reconstruct and remove the interference.

Estimation and cancellation of interferences in automotive radar signals

“…It was shown in simulations that the derivative of the signal is dominated by the interference component [4], so the above approximation is valid. The only exception is the time period when dϕ Int (t)/dt ≈ 0.…”

“…B Int and T c,int thereby describe the bandwidth and ramp duration of the interfering radar sensor. The time-frequency behavior is determined by the slopes of the transmitted chirps [2,4]. The interference baseband signal is described generally as with ϕ Int (t) = at 2 + bt + c,…”

“…In the next step, the amplitude A Int is determined. Therefore, an initial real-valued interference signal is calculated asŝ 4 with an arbitrary value Int . With a scaling factor α, the real-valued interference-free signal is estimated asŝ…”

“…The generation of such interferences is described in Section 2. As a countermeasure we developed a method to remove the interference from the receive signal [4]. This work was carried on and an improved version of this method is derived in Section 3.…”

Mitigation of automotive radar interference

“…where received signal of interest is Note that, the interference is time-limited and has an oscillatory behavior (quadratic-phase signal) [12]. Figure 2 shows the behavior of beat and interference signals in time-domain with a dependency of LPF as described in (13).…”