Systems and devices for airflow measurements in rooms and air delivery ducts with low-cost, low-power, accurate, calibration-free, and compact wireless airflow sensors are provided. The system uses room and duct flow sonic anemometers and processing to measure air velocities and temperatures as well as allow control over the environmental conditioning systems. The anemometers use arrays of transmitter/receivers to simultaneously measure multiple sound paths and determine velocity vectors and volumetric flow paths. By transmitting in both directions along the paths between transceivers, differential times of flight (TOF) are measured. These determine both the velocity and temperature of the air along each path.