2
Communication Networks and Services
Communication networks provide support for a very wide range of healthcare and medical services. Telemedicine uses various types of networks so that physicians can share ideas, surgeons anywhere in the world can perform a single operation together irrespective of where the operating theatre is, nurses and paramedics can retrieve a patient’s record anytime anywhere. Hospitals and clinics use the network for everything from patient care to administrative work and inventory management. In this chapter, we learn about the fundamentals of telecommunication technology, with an emphasis on wireless networking, since most telemedicine applications require the flexibilities that wireless networking provides.
2.1 Wireless Communications Basics
To understand how telemedicine works, we must learn about fundamental telecommunications theory. Telecommunications is about delivery or exchange of information between different entities. The most primitive communication example is perhaps two persons talking to each other, where the voice that conveys information is transmitted through the air and reaches the ears of the person who listens. Any communication system would consist of a transmitter (sender), receiver (recipient), and a channel (the path where the information passes through), as illustrated in Figure 2.1. Here is how it works. The transmitter sends out information s(t). The notation s(t) is a function of time meaning the information content varies ...