Be flexible

Abstract

T raditionally, the cellular radio frequency (RF) transceiver market was dominated by bipolar complementary metal-oxide-semiconductor (BiC MOS)-based transceivers. While complementary metal-oxide-semiconductor (CMOS) was seen as a contending technology for some time, especially in the academic domain [1], the first products based on CMOS technology entered the cellular market only a few years ago [2]. Within a few years, the once-dominant position of SiGeBiCMOS technology was successfully tackled by CMOS, as depicted in Figure 1.This shift in technology favored a more "digital" centric transceiver partitioning, although the traditional analog architectures (e.g., direct-conversion receiver, direct modulation, or phase-locked loop (PLL)-based transmitters) remained. Sticking to the well-known analog architectures was possible, since 130 nm CMOS devices had enough headroom in terms of supply voltage and analog device performance. The ever-increasing requirements of multiband/multimode/multisystem cellular transceivers can be accommodated by utilizing the higher integration levels of digital blocks made possible with CMOS. Transceivers incorporating nine-band universal mobile telecommunications system (UMTS), including high speed downlink packet access (HSDPA) and high speed uplink packet access (HSUPA), quad-band global system for mobile communications (GSM)/general packet radio service (GPRS)/enhanced data rate for global evolution (EDGE) [4] are conceivable

Analysis of a Controller-Based All-Digital Phase-Locked Loop

“…The digital baseband applications are integrated in the most recent CMOS technology, while analog design is becoming increasingly difficult due to shrinking voltage headroom. Therefore, the implementation of wireless transceivers on a single chip requires digital realizations of analog functions [1,2]. A digital intensive approach provides several additional advantages: improved reusability with optimized area and power dissipation, higher degree of integration, and the use of automated computer-aided design tools [3].…”

Demands of highly piezoelectric materials for radio frequency acoustic wave devices

“…As a possible solution to relax this problem, the tunable RF front end has been paid much attention 30, 31. Development of high performance variable RF filters is vital for its realization.…”

Joint digital pre-distortion model based on Chebyshev expansion

“…The direct conversion transceiver due to its simplified and low-cost structure is the most popular architecture and the appropriate choice often used in wireless communication systems [1]. Despite the simplicity and integrability of this structure, there are problems due to its practical implementation of analog components especially in the applications of advanced modulation schemes with high peak to average power ratio (PAPR).…”