Английски език
Positioning in Wireless Communications Systems will show the principal differences and similarities of wireless communications systems and navigation systems. The book discusses scenarios which are critical for dedicated navigation systems such as the Global Positioning System (GPS) and motivate the use of positioning based on terrestrial wireless communication systems. The principal techniques for estimating the position of an MT using radio technology are also discussed.§The book introduces approaches for determination of parameters which are dependent on the position of the MT and also discusses iterative algorithms together with their computational complexity. Models for radio propagation and user mobility are important for performance investigations and assessments using computer simulations. Thus, channel and mobility models are explored, especially focussing on critical navigation environments like urban or indoor scenarios. Multipath and non line-of-sight propagation are the most important effects in this context, which degrade the positioning performance and, therefore, have to be modelled accurately.§Positioning in Wireless Communications Systems examines advanced algorithms, which mitigate or combat propagation effects, which are typical for wireless communication scenarios, such as multipath and non line-of-sight propagation. The performance of the discussed positioning techniques are explored on the basis of already existing and operable terrestrial wireless communication systems such as GSM[1] or UMTS[2] and it is shown how positioning issues are fixed in respective standards. For future wireless communications systems, multicarrier transmission based on OFDM is seen as a promising candidate. Based on currently existing signal and frame structure proposals, performance results are provided for OFDM based systems.
