According to this technique , two cuffs are applied to the patient s arm during the period of nibp measuring . the upper cuff supplies varied pressure to the arterial vessels , meanwhile the lower cuff acts as a stethoscope to detect pulse signals 雙袖帶血壓測量技術(shù)建立在傳統(tǒng)血壓測量技術(shù)的基礎(chǔ)上,結(jié)合柯氏音和示波法測量的優(yōu)點,讓自動準(zhǔn)確的測量成為可能。
At the same time , it uses a frequency translator to obtain a frequency shift , which is equal to the brillouin frequency in fiber . then the detecting pulsed light and the cw reference light can coherent . this method greatly improved the system ’ s sensitive and signal to noise ratio ( snr ) 同時在探測光路中引入一個光移頻環(huán)路,使探測光移頻后再經(jīng)光纖中布里淵頻移,其后向布里淵散射光頻率與參考光束大致相當(dāng),可進(jìn)行相干自外差探測,大大提高了系統(tǒng)的探測靈敏度以及系統(tǒng)的信噪比。