Millimeter wave radar is a radar that works in the millimeter wave band, millimeter wave (mm wave) is a special class of radar technology that uses short- wavelength electromagnetic waves. Generally, millimeter waves refer to waves in the frequency range of 30 to 300 GHz (with a wavelength of 1 to 10 mm). Millimeter waves are essentially electromagnetic waves. The frequency of millimeter waves is special, higher than radio, lower than visible light and infrared, and the frequency range is approximately 10GHz-200GHz. Millimeter wave is between microwave and THz (1000GHz), which can be said to be a subset of microwave.

A millimeter-wave radar is a radar that operates in the millimeter-wave band. It uses the echoes of obstacles reflected after the electromagnetic waves are emitted to continuously detect them, and calculate the relative speed and distance to surrounding obstacles. Its advantage is that it has a very strong penetration rate. It can accurately detect objects through light, rain, dust, fog, or frost. It can work in a dark environment, but the limitation is that it cannot detect pedestrians and it has errors in metal recognition. Millimeter-wave radar's image is not as fine as that of lidar, and the delay is 100MS.

The common frequency bands of millimeter-wave radar in the automotive field are divided into: 24-24.25 GHz, 77 GHz, 79-81 GHz. Millimeter-wave radar has a long history of in-vehicle application. It is another mature solution other than vision cameras. The frequency of application is also increasing. Development of driverless technology promotes growth of millimeter wave radar market. Self-driving car is an intelligent vehicle. It is an automated vehicle that can partially or fully replace the driver's driving behavior, self-driving car is the highest form of smart car development. Unmanned driving consists of sensors, controllers and actuators, corresponding to the three functional modules of perception, decision-making and execution. The driverless industry chain includes: 1. Hardware components, including various sensors such as lidar, camera, integrated computing and processing platform, and traditional automotive components such as engine, body and integrated control bus; 2. Software components, including driverless operating systems (including sensing, planning, control, car interconnection, data platform interface, etc.), high-precision map data, etc. 3. Vehicle manufacturing. 4. Operational Services.

With the increase of ADAS penetration, millimeter-wave radar, as one of the important sensors in driverless technology, has huge market potential. Global millimeter wave radar market was valued at 3472 Million US$ in 2018 and is projected to reach 10429 Million US$ by 2024, at a CAGR of 20.12% during the forecast period

Key players in global millimeter wave radar market include: Continental, Bosch, Denso, Innosent, Autoliv, Delphi, TRW, FujitsuTen, Valeo, Rfbeam, Velodyne Lidar, Hitachin etc.