Impact of Ultra Wide Band (UWB) on Highways Microcells

The Federal Communications Commission (FCC) agreed in February 2002 to allocate 7.5 GHz of spectrum for unlicensed use of ultra-wideband (UWB) devices for communication applications in the 3.1–10.6 GHz frequency band. The move represented a victory in a long hard-fought battle that dated back decades. With its origins in the 1960s, when it was called time-domain electromagnetics, UWB came to be known for the operation of sending and receiving extremely short bursts of RF energy. With its outstanding ability for applications that require precision distance or positioning measurements, as well as high-speed wireless connectivity, the largest spectrum allocation ever granted by the FCC is unique because it overlaps other services in the same frequency of operation. Previous spectrum allocations for unlicensed use, such as the Unlicensed National Information Infrastructure (UNII) band have opened up bandwidth dedicated to unlicensed devices based on the assumption that “operation is subject to the following two conditions: This device may not cause harmful interference (harmful interference is defined as the interference that seriously degrades, obstructs or repeatedly interrupts a radio communication service), and this device must accept any interference received, including those interferences that may cause undesired operation. This means that devices using unlicensed spectrum must be designed to coexist in an uncontrolled environment. Devices using UWB spectrum operate according to similar rules, but they are subject to more stringent requirements, because UWB spectrum underlays other existing licensed and unlicensed spectrum allocations. In order to optimize spectrum use and reduce interference to existing services, the FCC’s regulations are very conservative and require very low emitted power. UWB has a number of advantages which make it attractive for consumer communications applications. In particular, UWB systems • Have potentially low complexity and low cost; • Have noise-like signal characteristics; • Are resistant to severe multipath and jamming; • Have very good time domain resolution. The spectrum for the Universal Mobile Telecommunications System (UMTS), which support voice and data services, lies between 1900 MHz to 2025 MHz and 2110 MHz to 2200 MHz. 2