The research and development of advanced assisted driving systems has driven the market's demand for sensors, such as cameras, radars, and LiDAR, which OEMs want to achieve at a lower price with smaller, faster components and to achieve the same or higher level of security. According to semiconductor engineering, the advanced auxiliary driving system usually involves the safety functions of automatic emergency braking, lane detection and rear object warning, radar is the most widely used technology, and another emerging technology is the use of pulsed laser light measurement distance. Since there is no single technology to cover all the ancillary and self-driving systems, some vehicles use a combination of advanced visual systems and radars, which in the future may be incorporated into the light. Each technology has its own advantages and disadvantages, such as the cost of optical tatsu far higher than the radar system, but can be more accurately identify objects, but the light up in the weather conditions are not very restrictive, radar, although not affected by the weather, but can not be as accurate to determine the size and shape of the object. Advanced Vision is an important part of the use of either radar or optical technology. In recent years, camera sensors have performed more and more tasks, including road indicator detection, lane departure warning, headlights control, parking assistance, driving surveillance, but camera sensors in the dark, rain, fog or snow under the poor performance, its dynamic range and near-infrared sensitivity need to be further improved. Today's vehicle radar module is rather cumbersome to integrate different process chips, and in order to reduce size and cost, NXP (NXP), Renesas (Renesas) and Texas Instruments (TI) and other chip manufacturers are using different processes to develop integrated radar chipsets. Radar to distinguish the range of objects by the transmission and reflection of the electromagnetic wave signal, speed and angle, the car usually carries long-distance (LRR) and short distance (SRR) radar, the former is used for adaptive cruise and automatic emergency brake, millimeter wave frequency is 77GHz, sensing range is 160~220 meters, the latter is used to detect lane, Keep the car out of the driveway, the frequency is 24GHz and the sensing range is $number meters. Long-distance radar modules usually contain micro-controller (MCU) and RF transceiver and other components, transceiver will be transmitted through the link radar data to the microcontroller processing. The German instrument launches a single chip radar product combined with microcontrollers and transceivers, offering a higher degree of integration and low power than a 2-chip solution, which reduces size and makes the bill of materials (BOM) optimal. The short-range radar module is designed to be more groundbreaking, with the exception of the frequency bands evolving from 24GHz to the more efficient 79GHz, and the rear-corner radar module is also transformed from a decoupled to a chipset solution. In addition to the German instrument, Adi and Renesas are developing 28 NM CMOS 77/79GHZ radar components, and GlobalFoundries also offers 22 nm fd-soi process options. If the radar resolution is high enough, the object can be effectively detected, but the radar can not identify whether the object is a human or a dog, so the need for a camera to help understand the surrounding environment, it will require faster graphics processing and depth learning techniques. Because of the low cost of radar sensors, favored by most OEM plants, but the resolution of the radar solution is not up to the requirements of fully automatic driving applications, so manufacturers are developing a new generation of radar, using the novel antenna design and advanced processing algorithms, as well as imaging radar (imaging radar) and other technologies to shorten the gap with the light up, or even replace the light up. As for the optical technology is also progressing, the cost continues to reduce, and towards solid-state lasers, new continuous waveform version development. By using a series of optical pulses to measure the return flight time, the optical 3D high-resolution map is constructed. Optical Tatsu technology can be roughly divided into mechanical, micro-computer (MEMS), mixed solid three types. Mechanical light is used in high-end industrial markets, MEMS is a new solution, and others are committed to the development of smaller, more compact solid-state optical systems, with less active parts used by solid-state light. Velodyne is used by the efficient power conversion company based on gallium nitride (Gan) technology for laser-driven bipolar drive chip. The switching speed of gallium nitride is 100 times times that of silicon, plus the ability of high voltage and current, so that each pulse can be loaded with more photons to improve the visual distance and resolution of the optical system.
