DSP cross-correlator for use in a thermal flow meter

The design realisation and performance of a thermal flowmeter using real-time Cross Correlation based on digital signal processing (DSP) are described. The system employs a hybrid circuit with a TMS320C50 DSP chip to interface a thermal flow meter to measure the flow velocity. A compact, high-speed and low-cost hardware implementation was obtained. Using this system data from two temperature sensors was sampled and cross-correlation Was performed within 384 msec and the flow velocity was calculated real-time with an inaccuracy smaller than 2% in a range from 2 mm/sec to over 50 mm/sec