TABLE OF CONTENTS This chapter serves as a brief, and hopefully painless, introduction to the basic concepts and terminology of metrology, with emphasis on those topics that are most pertinent to wireless LAN (WLAN) devices. The various types of test instruments generally used during all phases of the design and testing of WLAN devices, systems and networks are also presented, with some indication as to what each piece of test equipment might actually be used for.
Metrology is defined as "the science of measurement". The term is generally applied to both experimental and theoretical determinations of values, usually within Scientific and technical fields. The science of metrology predates the Industrial Revolution; indeed, it was essential for the mass-production methods that led to the modern manufacturing.
The terms "quantitative" and "qualitative" both refer to means of analyzing or describing the properties of something, typically a physical or logical entity. In qualitative analysis, the properties are described in terms of classifications or attributes, or assessed relative to something else. For example "color" is a qualitative property, and is expressed in terms of arbitrarily assigned tags such as "red", "orange", and so on. A quantitative property, however, exists in a range of magnitudes, and can therefore be measured and expressed in numeric forms. Continuing the example, a quantitative version of "color" (for physicists and photographers) is color temperature, which is the temperature in Kelvin to which a black body must be raised to emit light of...
