Universal Mobile Telecommunication System

The 3G networks using the Universal Mobile Telecommunications Systems standard have been in operation for a few years now. They offer an enormous increase in bandwidth and can theoretically transmit data at speeds of as much as two megabits per second (Mbps). They are also relatively easy to use. 

In the year 2000, at the peak of the dot-com bubble, many governments around the world allocated or sold licenses to offer high-speed wireless (third generation) telephone services. The sales of these UMTS (Universal Mobile Telecommunications System) licenses produced in some of these countries large windfalls for their governments. 

An example for a filter design is given in Reference 58. Because of the considerably low working frequency of the UMTS (Universal Mobile Telecommunication System)-filter (about 2 GHz), a combline topology was chosen to achieve a small filter size. Figure 9.72 shows a drawing of the filter witiiout external grotmd planes. 

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