["Yes, a 60 GHz mmWave radar sensor can be used for counting people in a room, as it offers high precision in detecting and tracking movement. However, the SeeedStudio 60 GHz mmWave sensor is more commonly used for presence detection and tracking, not specifically for counting people.
For accurate people counting, you might want to consider sensors like the Texas Instruments IWR6843 or the Infineon BGT60TR13C, which are designed for more complex tasks like people counting and occupancy monitoring with high accuracy. These sensors can differentiate between multiple individuals, making them a better fit for your use case."