This Chapter describes the methods of a proximity coupling RF vital sensor. The methods are mainly divided into two categories: the chest wall sensor and the wrist pulse sensor. For each part, the theoretical considerations, simulation results, and experimental results on methods for efficiently enhancing the sensitivity of the sensors are described in detail. In addition, we introduce an autoregressive (AR) model which is one of the parametric spectral analyses suitable for vital sign detection.

Chapter Contents:

• 2.1 Introduction
• 2.2 Chest wall sensor
• 2.2.1 SAW filter system
• 2.2.2 PLL system
• 2.2.3 Reflectometry system
• 2.3 Wrist pulse
• 2.3.1 Injection-locked PLL
• 2.3.2 Reflectometry system with array resonator
• 2.3.3 Interferometry system
• 2.4 AR method for improved vital sign estimation
• 2.5 Conclusion
• References

Inspec keywords: biomedical measurement; biosensors; autoregressive processes; microwave measurement; biomedical equipment

Other keywords: near-field proximity sensor; RF biosensor techniques; chest wall sensor; AR model; proximity coupling RF vital sensor; vital sign detection; sensor sensitivity; autoregressive model; wrist pulse sensor; microwave biosensor techniques; parametric spectral analyses

Subjects: Other topics in statistics; Probability theory, stochastic processes, and statistics; Microwaves and other electromagnetic waves (biomedical imaging/measurement); Microwave measurement techniques; Electrodiagnostics and other electrical measurement techniques