Instrumentation - Intro to Biomedical Engineering

examine a complex function example to compute magnitude and phase angle, using complex conjugate multiplication and real and imaginary numbers from signals and systems.

Explore how noise distorts signals and affects analysis, including voltage noise and environmental noise at 60 Hz. Learn how signal-to-noise ratio in decibels and both amplitude and power forms relate.

Examine the four main signal types—sinusoidal, exponential, delta (impulse), and rectangle functions—and their roles in signal and system analysis, including linearity.

Reinforce core data acquisition concepts in biomedical instrumentation by explaining essential components—sensors, signal conditioning, and analog-to-digital converters—through solved problems, including voltage range calculations, sampling rate, and duty cycle.

Explore operational amplifiers, high-gain, high-input-impedance devices that amplify weak signals from the body; learn about inverting and non-inverting configurations, frequency dependence, and instrument amplifiers.

Explore instrumentation amplifiers that provide large gain for very low level biomedical signals amid noise with a three-op-amp design, high input impedance, and high common-mode rejection ratio.

Explore how microcontrollers provide simple processing systems to control and analyze signals, focusing on open-source Arduino Uno/Nano, sensors, PWM, ADC, digital and analog I/O for beginners.

Explore the stable mode of the 555 timer as a free-running oscillator that generates continuous rectangular pulses, with frequency and duty cycle set by two resistors and one capacitor.

Power supplies convert ac wall voltage to dc to power biomedical systems with stable, low-noise output. Compare lab, standard, usb, and battery supplies for voltage, current, noise, and stability considerations.

Review the concepts from 555 timers, modes and duty cycles, Schmitt triggers and auto Schmitt history, and AC and DC power supplies with voltage dropout regulators and pros and cons.

Understand how materials absorb photon energy by electrons, with absorption depending on wavelength and luminescence emitting longer wavelengths; Beer-Lambert law links attenuation to concentration for spectroscopy and fluorescence applications.

Photodiodes are semiconductor devices that convert light into a photocurrent via photon absorption. Responsivity depends on detector material and can be tailored with filters and lenses for varied applications.

Explore the pulse oximeter circuitry, from finger clip and led drivers to the photodiode detector, filters, amplifiers, analog-to-digital converter, and microprocessor that quantify oxygen levels.

Explain pulse oximeter waveforms, how interference affects detection, and walk through an example using 660 nm and 940 nm to calculate oxygen concentration, yielding about 82.2% and noting clinical ranges.