 the performance of real time services. In bad weather conditions adaptive modulation not only guarantees that real time voice and other applications do not experience signal degradation but also supports non-real time data applications at a lower bandwidth without performance degradation. 7.3.1.3 TDM/IP Hybrid Microwave Radios The Hybrid Microwave Radio concept involves efficient transport of packet switched traffic while still supporting legacy TDM/ATM. The platform transports data traffic using Ethernet interfaces while efficiently transporting TDM traffic using E1/T1 ports. Both Ethernet and TDM dynamically share the same overall bandwidth that is, 100% bandwidth could be dedicated either for TDM or for Ethernet or to a mix of TDM and Ethernet traffic. These radios support adaptive modulation, 63 or more E1s and around 400 Mbps. Some of the TDM only radios can be upgraded to hybrid mode with necessary software and hardware enhancements. 7.3.2 Gigabit Ethernet Radios The transition from voice to bandwidth hungry data applications is pushing the envelope on backhaul networks. The migration towards EPS and IMT-Advanced which targets 100 Mbps for high speed users and 1.0 Gbps for stationary users is further complicating the matters for backhaul network designers. The current E1/T1 leased lines and microwave radios are not designed to cater for such capacities. One answer to this problem comes in the form of Gigabit Ethernet Radio Link technology. Transmission Networks 7.3.2.1 Overview The Gigabit Ethernet Radio Link technology operates in the upper frequency bands (millimeter bands), between 70 and 100 GHz. The 71-76 GHz and 81-86 GHz bands are considered to be the most suitable frequency bands for point-to-point Gigabit radio links. FCC in USA and Ofcom in UK allocated 80 GHz spectrum for fixed wireless communications in 2003 and 2007 respectively. These systems are designed to provide 1.0 Gbps of capacity in a single radio channel ~1.75-2.0 GHz). This technology is not feasible in lower frequency bands (10-40 G