Terrestrial Trunked Radio (TETRA) has become the tool to design any type of public security systems, in particular due to the strongly increased security demands for mobile systems. In this book, the authors show how TETRA can be strongly improved and these improvements will most probably be part of future TETRA standards. The areas examined include channel assignment and multiple access techniques, video transmission, wireless LAN integration, and the establishment of multiple wireless mesh networks. Since the requirements for these networks is security, the authors show that innovative techniques such as those based on chaotic signals can be used in order to maximize security. The book is a vital reference point for researchers with ambition to find the general solution for modern problems of public safety.