Physical Principles of Wireless Communications : CRC Press : 9781439878972 : 1439878978 : 26 Apr 2012 : "Preface to the second edition The technology of wireless communications is changing rapidly. In the less than 5 years that have elapsed since the writing of the first edition of this book "smart phones" with internet access have become ubiquitous makingit appropriate to add material in the first chapter describing third generation (3G) and fourth generation (4G) cell phone systems. Beyond that natural update, I have received many suggestions for adding new material on topics that were treated lightly or omitted in the first edition. Primary among these were discussions of the relation between the basic laws of quantum and relativistic physics and the engineering of modern wireless communication systems. A section has been added describing Planck's Law of Blackbody Radiation. This has been followed by a detailed description of the assumptions made to derive from this law the engineer