Circuits and Signals for Biomedical Engineering

Biomedical engineering asks you to be fluent in two languages at once: the physiology that produces a signal and the electronics that capture it. This book teaches both in the same chapter.

Most introductory texts make you choose: learn circuits first and hope the biology makes sense later, or learn physiology first and treat the electronics as a black box. Circuits and Signals for Biomedical Engineering refuses that split. You will build circuit analysis from Ohm's and Kirchhoff's laws up to impedance and transfer functions, then design the instrumentation amplifier that pulls a one-millivolt electrocardiogram out of power-line noise. Every concept is anchored to a measurement a biomedical engineer actually makes.

The electrode chapters explain half-cell potentials and motion artifact, so you understand why a good electrode matters as much as a good amplifier. The signals chapters take you through convolution, Laplace and Fourier methods, sampling, aliasing and digital filter design, each with MATLAB you can run on a real recording. Later chapters move outward to physiological sensors, the physics behind radiography, ultrasound and magnetic resonance, compartment modeling, and the hydrogels and scaffolds used in tissue engineering. The result is a single continuous path from a biopotential on the skin to a processed signal on a screen, and from there to the materials that repair the body.

What you will learn:

• Apply Ohm's law, Kirchhoff's laws and Thevenin equivalents to bioinstrumentation circuits
• Analyze capacitors, inductors and the frequency domain, including impedance and transfer functions
• Design operational amplifier and instrumentation amplifier stages for low-level biopotentials
• Explain electrode behavior, half-cell potentials and motion artifact in ECG, EEG and EMG recordings
• Identify and reduce noise, interference and grounding problems while maintaining patient isolation
• Use convolution, Laplace transforms and Fourier analysis to describe biomedical systems
• Sample, anti-alias and digitally filter biosignals with runnable MATLAB examples
• Select sensors and transducers for physiological measurement
• Describe the principles of X-ray, ultrasound and magnetic resonance imaging
• Model physiological transport with compartment models and understand hydrogels and scaffolds for tissue engineering

Who it is for: Bioengineering undergraduates taking a first circuits or signals course, career changers entering biomedical engineering from another technical field, and anyone who needs to read a schematic and a physiological waveform with equal confidence. No prior circuits background is assumed; the mathematics is developed as the applications require it.