MR76 77GHz MMW Radar User Manual
MR76(v1.1)2020-3-10
Hunan Nanoradar Science and Technology Co., Ltd
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1.3 Radar principle
The MR76 adopts the modulation method of FMCW (Frequency Modulated Continuous Wave). The
basic principle is that the transmitted wave is a high-frequency continuous wave, and its frequency
changes with the sawtooth wave rules by time. The changing rules of echo frequency received by the
FMCW is the same as the transmitted frequency, which is sawtooth wave rules. However, there is a time
difference. The target distance can be calculated by using thisl time difference.
Figure1 FMCW radar block diagram
Taking the sawtooth frequency modulated continuous wave as an example to briefly introduce the radar's
ranging/velocity measurement principle. As shown in Figure 1.1, blue is the transmitting signal
frequency, yellow is the receiving signal frequency, the sweep period is T, the sweep bandwidth is B, the
transmitted signal is transmitted through the target, and the echo signal has a delay, in the sawtooth
frequency change rules, the distance measurement can be performed on both the rising edge and the
falling edge.
1.4 Radar FOV
The MR76 77GHz millimeter wave radar is a mid-range radar. It can detect target distance, velocity and
position information by receiving radar reflections. Its FoV can reach ±45° in the close range and ±9° in
the medium range.