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79GHz Figure 3


Figure 3a: Today safety system concept: heterogenic approach with different radar systems resulting in a different performance, interference risk and application portfolio


Figure 3b: Next generation safety system layout: a common radar sensor from 76 GHz to 81 GHz covering all applications, interference free operation (shown partition is only one possible example)


“A better target discrimination capability will be available at 79GHz, thanks to the bandwidth of 4GHz”


the steering). The long-term goal of zero accidents requires a 360° surround vision or semi-autonomous/fully autono- mous driving. These new and complex applications require short-range radars (SRR) able to meet demanding require- ments: better target discrimination capability, high spatial resolution and reduced mutual interference. A wide range of applications can be supported by radars


using the 79GHz band (see Table 1), improving their per- formances. Wide bandwidth and a high power limitation, enabling better resolution and better object discrimination,


Figure 2: Comparison between recognition at low and high spatial resolution


are essential for a wide range of safety functions: for instance, the Collision Warning System (CWS) and Collision Mitigation System (CMS), which provide an acoustic and/ or optical warning to the driver and may prepare the brak- ing system if the driver doesn‘t generate the necessary decel- eration to avoid the collision, or the Vulnerable road User Detection (VUD) which supports the detection of vulner- able road users (cyclists or pedestrians) in front (potentially also on the side of the host vehicle) in order to enable warn- ing or assist brake functions.


BENEFITS OF THE 79 GHZ BAND Several studies, such as those carried out under the EU founded project MOSARIM (https://assrv1.haw-aw.de/) have shown different advantages in the use of 79GHz band. For instance, multiple objects cannot be distinguished if they appear in the same range gate and are fused to one virtual object. A better target discrimination capability will be avail- able at 79GHz, thanks to the bandwidth of 4GHz. Also spa- tial resolution, allowing an exact location determination that is essential for safety-critical applications, is directly linked to the available bandwidth. It is very important to reduce unjustified system responses or false alarms: the higher the used bandwidth, the better the spatial resolution will be, as shown in Figure 2. Radar devices are also much smaller at 79 GHz compared


to 24 GHz: HF-circuit structures and antenna sizes directly depend on the wavelength used. The higher the operational frequency, the smaller the total size of the radar device. The


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