Road Surface Characteristics for the Automotive 77 GHz Band

In order to achieve a safety proof of autonomous driving using simulations, information about the environment has to be determined, which is not sufficiently available until now. This work is concerned with road surfaces and their scattering of radar signals. As it is not enough to look at geometries, as it is already done for many ray tracing approaches, also material and composition have to be investigated. Therefore, measurements are performed using a SAR setup in a laboratory as well as open space measurements using a radar evaluation board on a testing area of the Federal Highway Research Institute. The SAR setup enables a quick estimation on differences in reflection of different test objects. With the result from the latter values for the relative permittivity are calculated for different road surface types exploiting Fresnel's equations. The differences in reflection depending on material and surface structure of the road see in the measurements of both setups are discussed in the paper.

A Prototype of Automotive 77 GHz Radar

Introduction. Automotive radars are the main tools for providing traffic safety. The development of such radars involve a number of technical difficulties due to the manufacture of high-precision extremely high-frequency (EHF) printed circuit boards. To facilitate the process of creating such devices, the existing algorithms for radar information processing should be debugged using prototypes from manufacturers of mm-band transceivers. However, the parameters of such boards are not known in advance, and the actual operating conditions of the as-produced automotive radars raise new challenges to target tracking algorithms. Therefore, checking the performance of such boards is a relevant research problem.Aim. To evaluate the performance of a millimeter-wave automotive radar prototype and to test target tracking algorithms using this prototype.Materials and methods. An original target tracking method was used, which considers the constraints on the use of additional data sources about the radar carrier movement.Results. An experimental performance evaluation of a 77 GHz automotive radar prototype was carried out. The effectiveness of primary processing for the target class “vehicle” in the millimetre range was checked. Original algorithms for target tracking were proposed and tested.Conclusion. The obtained results show that the prototype board of a transceiver chip is capable of testing tracking algorithms without creating an own automotive radar prototype. Thus, the developmental process can be significantly shortened. Moreover, after creating a hardware solution, the developer obtains a reference device to test and configure an own product without using extremely expensive and rare EHF equipment.

A 77-GHz High Gain Low Noise Receiver for Automatic Radar Applications

In this paper, a high gain 77-GHz receiver with a low noise figure (NF) was designed and implemented in a 40-nm CMOS process. With the purpose of making better use of active devices, an extra inductor, Ld, is adopted in the new neutralization technique. The three-stage differential low noise amplifier (LNA) using the proposed technique improves the voltage gain and reduces the NF. The receiver design utilizes an active double-balanced Gilbert mixer with a transformer coupling network between the transconductance stage and the switch stage. The flicker noise contribution from the switch MOS transistors is largely reduced due to the low DC current of the switch pairs. The LO signal is provided by an on-chip fundamental voltage-controlled oscillator (VCO) with a tuning range from 70.5 to 78.1 GHz. A conversion gain of 32 dB and a NF of 11.86 dB are achieved at 77 GHz by the designed receiver. The LNA as well as the mixer consume a total DC power of 33.2 mW and occupy a core size of 1 × 0.38 mm2.