Millimeter Wave: A Novel Approach for Integrating Radar and Communication for Autonomous Driving

Joint operation of radar and communication is one of the most essential arena of research for the past two decades in the field of intelligent transportation systems. For commercial viability, the joint system must be cost effective with lesser complexity, minimized intercarrier interference between the systems so that the same can be used autonomous driving of smart transportation system. Here, we have proposed a joint radar communication platform using 77 GHz millimeter wave vehicular radar. The reason behind choosing this radar to provide a common platform is that this radar has become very popular as vehicular radar nowadays. We have used the chirp signal as a common carrier frequency for radar and communication; but, unlike the radar, the chirp frame used to modulate the communication data is made orthogonal. The two chirp signals of identical frequency are added together and transmitted. Because of the orthogonal relationship between the radar and the communication signal, intercarrier interference is reduced. As well as the FMCW chirp radar is inherently Doppler tolerant, therefore, precision velocity estimation is also possible. Subsequently, in this work, we have assessed the behavior of 77 GHz automotive FMCW radar with single antenna as well as with multiple antennas. These high-frequency radars can combat the harsh environmental conditions such as low-light quality and poor weather. Hence, 77 GHz FMCW radar sensors are chosen in the automotive applications. Results proved that FMCW automotive STAP radar gives enhanced performance in respect of target car appearance in Doppler processing and the range-Doppler coupling compensation with low bit error rate.