Calterah’s automotive multi-mode mmWave radar reference design is a system-level design supported by the Alps family of the 77-GHz auto-grade and fully-integrated mmWave radar SoC chips. It integrates the functions of forward-looking radar and corner radar and offers 3 operation modes of Long-Range Radar (LRR) Mode, Medium-Range (MRR) Radar and Short-Range Radar (SRR) Mode. This reference design enables real-time detection of objects in front of and beside a vehicle and collection of their information including range, relative velocity, azimuth, etc., thus satisfying the demand for features like adaptive cruise control (ACC), automatic emergency braking (AEB), forward collision warning (FCW), blind spot detection (BSD), etc.

Figure 1. Multi-Mode Radar RDP Board

Features

Calterah’s automotive multi-mode mmWave radar reference design has the following features:

• Three operation modes: LRR Mode, MRR Mode, and SRR Mode
• 4 transmitters and 4 receivers (4T4R)
  ○  LRR Mode: 1T4R
  ○  MRR Mode: 3T4R TDM-MIMO
  ○  SRR Mode: 3T4R TDM-MIMO
• Flexible combination of modes, like combining LRR Mode and MRR Mode to achieve the function of forward-looking radar or combining MRR Mode and SRR Mode to achieve the function of corner radar
• Combination of LRR, MRR, and SRR to achieve comprehensive detection with the maximum detection range of 191 meters and the broadest FOV of -80° to 80°.
• Multi-mode tracking

Figure 2. Choosing Modes on Multi-Mode Radar Board

Forward-Looking Radar

Calterah’s automotive multi-mode mmWave radar reference design can achieve the function of forward-looking radar with the specifications listed below.

• LRR Mode and MRR Mode work by turns.
• Scheme of each mode:
  ○  LRR Mode: 1T4R
  ○  MRR Mode: 3T4R TDM-MIMO
• The maximum detection range is 191 meters and the broadest FOV is 80°–80°.
• Fusion of LRR and MRR raw data before tracking
• Refreshing rate of 20 Hz

Table 1. Specifications of Forward-Looking Radar

Figure 3. Diagram of Forward-Looking Radar Wave Beam

Figure 4. Timing of Forward-Looking Radar Operation Modes

Corner Radar

Calterah’s automotive multi-mode mmWave radar reference design can achieve the function of corner radar with the specifications listed below.

• MRR Mode and SRR Mode work by turns.
• Schemes of MRR Mode and SRR Mode are both 3T4R TDM-MIMO.
• The maximum detection range is 91 meters and the broadest FOV is -80°–80°.
• Fusion of MRR and SRR raw data before tracking
• Refreshing rate of 20 Hz

Table 2.  Specifications of Corner Radar

Figure 5. Diagram of Corner Radar Wave Beam

Figure 6. Timing of Corner Radar Operation Modes

Tracking

Calterah’s multi-mode radar reference design provides flexible tracking intervals to support tracking with variable cycles and fusion of 2D and 3D data, which improves robustness. It supports signal-level tracking fusion, decision-level tracking fusion and detection of objects both in front of and behind a vehicle.

Figure 7. Flow of Multi-Mode Radar Tracking Process