Design of Electromagnetic Probe Having Reduced Base Line Drift for Blood Flow Measurement

摘要

An improved design for electromagnetic probe for blood flow measurement is presented. The probe produces a magnetic field in the column of blood to induce a voltage as per Faraday's laws. The mechanical and electromagnetic structures are designed to reduce the effect of base line drift and signal variations with time which are very common in electromagnetic flow measurement systems. A signal with very less noise and drift is induced with a sensitivity of more than 80 mV/lpm. The signal has a linear variation with flow rates and need no frequent calibration. Signal variations with time are negligible and had less power signal interferences and noisy spikes.