RF Front-end Module Research Articles

Low-loss LTCC cavity filters using system-on-package technology at 60 GHz

In this paper, three-dimensional (3-D) integrated cavity resonators and filters consisting of via walls are demonstrated as a system-on-package compact solution for RF front-end modules at 60 GHz using low-temperature cofired ceramic (LTCC) technology. Slot excitation with a /spl lambda/g/4 open stub has been applied and evaluated in terms of experimental performance and fabrication accuracy and simplicity. The strongly coupled cavity resonator provides an insertion loss 20.6 dB over the passband (/spl sim/0.89 GHz), and a 3-dB bandwidth of approximately 1.5% (/spl sim/0.89 GHz), as well as a simple fabrication of the feeding structure (since it does not require to drill vias to implement the feeding structure). The design has been utilized to develop a 3-D low-loss three-pole bandpass filter for 60-GHz wireless local area network narrow-band (/spl sim/1 GHz) applications. This is the first demonstration entirely authenticated by measurement data for 60-GHz 3-D LTCC cavity filters. This filter exhibits an insertion loss of 2.14 dB at the center frequency of 58.7 GHz, a rejection >16.4 dB over the passband, and a 3-dB bandwidth approximately 1.38% (/spl sim/0.9 GHz).

Comparison of RF integrated passive devices on smart silicon and glass substrate

In this paper, we fabricate RF integrated passive devices (RFIPDs) on two types of substrate. One is smart silicon substrate with a 25-μm-thick SiO2 surface, and the other is glass substrate. A low-cost manufacturing technology, BCB interlayer, and 10-μm Cu plating process are used to implement high-performance RFIPDs. We investigate the power-handling performance with these two types of RFIPDs. Generally, RFIPDs are used for RF front-end module components, so handling power is very important factor. But, these two types of RFIPDs show different handling-power performances. In contrast to the 5.5-W power handling of the LPF on smart silicon substrate, that of the LPF on glass substrate is below 1.5 W (with CW power and 168 h operating time). © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 441–444, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20848

Integrated RF architectures in fully-organic SOP technology

Future wireless communications systems require better performance, lower cost, and compact RF front-end footprint. The RF front-end module development and its level of integration are, thus, continuous challenges. In most of the presently used microwave integrated circuit technologies, it is difficult to integrate the passives efficiently with required quality. Another critical obstacle in the design of passive components, which occupy the highest percentage of integrated circuit and circuit board real estate, includes the effort to reduce the module size. These issues can be addressed with multilayer substrate technology. A multilayer organic (MLO)-based process offers the potential as the next generation technology of choice for electronic packaging. It uses a cost effective process, while offering design flexibility and optimized integration due to its multilayer topology. We present the design, model, and measurement data of RF-microwave multilayer transitions and integrated passives implemented in a MLO system on package (SOP) technology. Compact, high Q inductors, and embedded filter designs for wireless module applications are demonstrated for the first time in this technology.

RF-system-on-package (SOP) for wireless communications

Anew industrial revolution, often called the “third wave” or information technology (IT), is in the making. The products of this revolution will require entirely different systems hardware technologies: those with multifunctions, such as digital, analog, RF, and optical circuitries. RF and microwave design and packaging have been established as key technologies of this revolution. The demand for increasingly higher rates of data, voice, and video drives RF technology to ever higher frequencies where bandwidth for channel capacity is easy to find. Such emerging high-performance applications as personal communication networks, wireless local-area networks (WLAN), and RF-optical networks have defined a trend toward more flexible and reconfigurable systems. They impose very stringent specifications never before reached in term of low noise, high linearity, low power consumption, small size and weight, and low cost. The RF front-end module is the foundation of these systems, and its integration poses a great challenge. Microelectronics technology, since the invention of the transistor, has revolutionized many aspects of electronic products. This integration and cost path has led the microelectronics industry to believe that this kind of progress can go on forever, leading to so-called “system-on-chip” (SOC) for all applications. But it is becoming clear that the production of a complete solution for the new wireless communication front-end is still a dream. When you consider the characteristics of an RF front-end module  high performance up to 100-GHz operating frequency  a large number of high-performance discrete passive components  design flexibility

Technology developments driving an evolution of cellular phone power amplifiers to integrated RF front-end modules

Millions of cellular phone power amplifiers (PAs) are produced every day worldwide using a great diversity of technologies. This is true both for the active devices, where various silicon as well as GaAs transistors are used, and for the PA architecture, in which MMIC, module, and discrete solutions compete. This paper gives an overview of the various technological and architectural choices and discusses their influence on the PA performance, notably the power efficiency and linearity. It sketches the future of PA development toward more functional integration, which may be obtained by two paths: integration on chip and added functionality in modules.

MM-wave integrated circuits and their applications to communication and automotive systems

After a short presentation of the market outlook of the commercial applications of millimetre-wave systems, we present three examples of a successful development of MMIC chip-sets: one chip-set for a full duplex Ka-band transceiver for a multipoint communication system; one chip-set for a 40 GHz MVDS subscriber terminal and, finally, one chip-set for a 76.5 GHz car radar system for ACC. In all three cases, a full MMIC architecture is used. In our view, this is the only solution to allow the high yield and high volume fabrication of the RF front-end modules at the very low costs which are required for market development.