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Models make or break the accuracy of a simulator. Although modern simulators have a wide range of models, device technology continually evolves, requiring new ones. Creating linear models is easy and straightforward. Nonlinear models, however, have been so difficult to create that engineers are often forced to live with...

This article continues the trend of previous publications, 1,2 to simplify the prediction of RF performance of systems designed for wireless digital communications. The first shows the correlation between sidelobes and intermodulation (IM) products. Sidelobes are the result of the spectrum re-growth when a digitally modulated signal is applied...

The satisfaction that mobile phones can provide is highly dependent on their autonomy. Three factors can be easily identified which have a strong influence on autonomy: the power consumption of the mobile phone, the intensity of the electromagnetic field near the mobile and the battery capacity. The first of...

Generally, an oscillator can be seen as a positive feedback system. It usually consists of an amplifier followed by a resonator, which is fed back to the amplifier input, as shown in Figure 1 . The amplifier task is to compensate for the losses in the resonator, and the...

The simplest quarter-wavelength, multi-port power divider, known as a Wilkinson divider, 1-2 provides a match at all ports, low loss, in-phase power splitting and high isolation between output ports. Historically, this device was reported earlier. 3-7 It was also described 5 together with the so-called Gysel-type combiner, 8 based...

Splitting an RF input signal within a VCR or television was never much of a design challenge for manufacturers when the signal was analog. That changed dramatically, however, when CATV systems made the transition from analog to digital to provide addressability, video on demand, Internet access and other services....

Modern communication systems often require narrow band filters presenting high selectivity and low insertion loss. When there are also stringent requirements on the overall dimensions of the filtering structure, it could become very problematic to select a suitable class of resonators having at the same time compactness and large...

Integrated voltage-controlled capacitors, usually known as varactors, are used in many electronic integrated devices for RF applications. 1 In particular, voltage-controlled oscillators (VCO) 2,3 and tuneable filters 4 are the two main applications. For good performance of integrated devices that have a varactor as a component, it is very...

In many applications, such as balanced power amplifiers, mixers and antenna systems, power dividers/combiners are required. Power dividers using quarter-wave lines become prohibitively large at the lower frequencies and result in MMIC chips of larger size and higher cost. The lumped-element approach, which uses lumped inductors and capacitors, is...

The fast fourier transform (FFT) approach to the method of moments (MoM) is well known for providing high accuracy, high dynamic range and robust electromagnetic (EM) analysis of planar circuits. The FFT consistently calculates the coupling between subsections to full numerical precision; no error is introduced by complex multi-dimensional...