Amplifiers

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The transmitter unit, contained in base stations for third generation cellular systems, requires a linear power amplifier to preserve signal integrity when amplifying composite signals associated with multiple channels. While the power amplifier must meet a number of requirements to be system level compliant, the design process generally emphasizes...

There is certainly no shortage of information about designing power amplifiers these days, and several books address the subject quite admirably. 1-6 However, as well as these books cover the theory and underlying logic of such designs, they do not tell the reader precisely how to do it. As...

Each of the many process technologies that can be used for RF power amplifiers - GaAs HBT, PHEMT, InGaP HBT and silicon RF MOSFET - have different advantages, such as better frequency characteristics, wider linearity and higher power capability. A fundamental comparison of the different process technologies is shown...

A new surface-mount technology (SMT)-packaged power amplifier has been introduced for wireless communications applications, including millimeter-wave point-to-point radio, local multipoint distribution services (LMDS), satellite communications (SATCOM) and very small aperture terminal (VSAT) use. The model XP1000P1 GaAs MMIC surface-mount power amplifier is a two-stage amplifier optimized for linear output...

Test applications that require microwave power from 1 to 18 GHz are usually addressed by two amplifiers, a solid-state unit to cover the low frequency range and a traveling-wave tube amplifier (TWTA) for the higher range. The input signal must be switched between the two amplifiers and, if there...

Today's investment in and commitment to meaningful, commercially viable research will determine the shape and prosperity of tomorrow's microwave industry. Following its introduction in 2001 the second Microwave Journal guide to European research projects highlights the studies being undertaken by academic and commercial establishments to develop the innovations that...

During the past decade, there has been significant progress in monolithic power amplifiers operating at RF and microwave frequencies over narrow and broadbands for both commercial and military applications. For numerous applications, including handsets, VSAT and transmit/receive modules, these amplifiers are produced in large quantities using MESFET, HBT and...

Cover Feature Low Cost Millimeter-wave Packaged MMICs United Monolithic Semiconductors S.A.S. Orsay Cedex, France Millimeter-wave technology is being recognized as having potential for emerging markets, such as broadband radio links for cellular base station backhaul networking and automotive safety systems. For such development to occur, however, the requested volumes...

Technical Features LDMOS Linearity and Reliability Laterally diffused metal-oxide-semiconductor (LDMOS) devices have been available as high power, low frequency amplifiers for almost three decades. The original devices had problems with linearity and reliability. More recent developments have improved the device performance and make LDMOS suitable in cellular base station...

Technical Feature Q- and V-band MMIC Low Noise Amplifiers This article describes MMIC low noise amplifiers for millimeter-wave applications using 0.15 µ m pHEMT technology. The design emphasis is on the active device model. The deficiency of conventional device models is identified. A distributed device model has been adapted...