A physiological monitor utilizes Faraday rotation measurements to estimate mean photon pathlengths through tissue. Germanium p-i-n structures may be fabricated over silicon or silicon-on-insulator substrates using silicon processing technologies. Further, the base station transmits a allowance signal for allowing a communication toward the mobile station of which propagation delay time is substantially equal to that stored in the memory in the base station. A conduit is connected a coupling at one end of the tube and the part.