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Determining cross-modulation interference is an important factor in the design of a code division multiple access (CDMA) mobile transceiver. The cross-modulation interference level directly affects the performance of the receiver's ability to overcome the spurious interferences, such as what the IS-98 1 calls single tone desensitization. A few papers...

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 term "one size fits all" has never applied to microwave test fixtures. They are instead almost always custom creations designed to serve a specific test application, and cannot easily be modified to meet other needs in the future. This has always presented a problem for cost-conscious designers. In...

The gigahertz transverse electromagnetic mode (GTEM) cell was first proposed in 1987 1 and subsequently patented in 1989 by D. Konigstein and D. Hansen 2 as a high frequency variant of the transverse electromagnetic mode (TEM) cell, which is also known as the Crawford cell. 3 The GTEM cell...

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...

Accurately measuring the power in wideband signals used in 3G and pulsed systems requires a power meter with a high bandwidth. To address this market condition, the ML2487A (single-channel) and ML2488A (dual-channel) high speed peak power meters have been developed that feature 20 MHz channel bandwidth, which is a...

Frequency synthesizers are fundamental building blocks in any wireless system. The need for reducing component count in wireless systems continues to drive synthesizer integration onto single systems-on-a-chip (SoC). Many multi-standard wireless products are emerging with combinations of WLAN 802.11a/b/g, GSM, Bluetooth, GPS and CDMA. One of the most challenging...

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...

One of the greatest challenges in characterizing new coaxial interfaces is to determine an accurate test configuration. When precision airlines are not available it is very difficult to obtain a true measurement of the device under test. It becomes necessary to design and implement calibration standards to eliminate the...

High frequency, voltage-controlled oscillators (VCO) are important components of modern RF systems. They are characterized by a set of parameters, which must be analyzed and optimized (for example, phase noise, frequency tuning range, tuning linearity and output power). Many studies are dedicated to the research of VCO characteristics. 1-8...