Automotive radar sensor with communication capability

In the last years short distance radar (SDR) systems for cars have been developed to the maturity phase. In order to use the sensors not only for comfort applications, but also for safety applications, it is essential to guarantee a high degree of reliability under all circumstances. One approach for increasing the reliability is to combine the data from different sensors, observing the complete car environment. A next step is to exchange sensor data between neighboured cars by a data link. So it is necessary to establish intervehicle communcation (IVC). This was the impulse to implement a system, which consists of a pulse radar at a center frequency of 24.125 GHz and a communication transceiver. The mainlobe of the pulse radar occupies a bandwidth of 250 MHz. The frequency band of the transceiver, which is small compared to the pulse spectrum with its 1.5MHz, is placed at the first sidelobe of the pulse spectrum. Because the bands are overlapping, the same RF frontend can be used, which decreases cost. The pulse radar is designed to allow simultaneous sensing over a range of nearly 40m and the communication link has a maximum range of 200m. In the following the basic concept and the signal processing of the radar and transceiver on Stratix®-FPGAs (EP1S25F780C5) from ALTERA™ are described.